Comparative nuclear magnetic resonance studies of diffusional water permeability of red blood cells from different species. VIII. Adult and fetal guinea pig (Cavia procellus)

The diffusional water permeability (P _d) of adult, pregnant female and fetal guinea-pig red blood cells (RBCs) was measured by a doping nuclear magnetic resonance (NMR) technique on control cells and following inhibition withp-chloromercuribenzene sulphonate (PCMBS). The values ofP _d were around 5.0 × 10^?3 cm/s at 15 °C, 5.3 × 10-3 cm/s at 20 °C, 6.6 × 10^?3 cm/s at 25 °C, 7.5 × 10^?3 cm/s at 30 °C and 8.6 × 10^?3 cm/s at 37 °C with no significant differences between adult, pregnant female and fetal RBCs. Systematic studies on the effects of PCMBS on water diffusion indicated that the maximal inhibition was reached in 10 min at 37 °C with 0.1 mm PCMBS. The values of maximal inhibition ranged from 70%–77% at 15–30 °C to 57%–63% at 37 °C in the case of adult and from 64%–67% at 15–30 °C to 51% at 37 °C in the case of fetal RBCs. The basal permeability to water was estimated at 1.1 × 10^?3 cm/s at 15 °C ,1.3 × 10^?3 cm/s at 20 °C, 1.6 × 10^?3 cm/s at 25 °C, 2.2 × 10^?3 cm/s at 30 °C and 3.2 × 10^?3 cm/s at 37 °C for adult and slightly higher values for fetal guinea pig RBCs as 1.6 × 10^?3 cm/s at 15 °C, 2.0 × 10^?3 cm/s at 20 °C, 2.4 × 10^?3 cm/s at 25 °C, 2.6 × 10^?3 cm/s at 30 °C and 4.2 × 10^?3 cm/s at 37 °C. The activation energy of water diffusion was around 22 kJ/ mol, with no significant differences between the adult pregnant female and fetal RBCs, and increased to about 40 kJ/mol in the case of adult and pregnant RBCs and 34 kJ/mol for fetal RBCs after incubation with PCMBS in conditions of maximal inhibition of water diffusion. The membrane polypeptide electrophoretic pattern of adult and fetal guinea-pig RBCs was compared with its human counterpart. The guinea-pig membrane contained higher amounts of spectrin (band 1 and 2), whereas the proteins in bands 4.1, 4.2 and 6 were present in lower amounts. Considerable differences in polypeptides migrating in the region of bands 7 and 8 and in front of them were apparent between the two sources of RBC membranes where some bands were present only in the guinea-pig RBC membranes. The adult guinea-pig membranes contained smaller amounts of proteins migrating in band 4.5 and lacked band 8.     

A human-mouse chimera of the alpha3alpha4alpha5(IV) collagen protomer rescues the renal phenotype in Col4a3-/- Alport mice

Collagen IV is a major structural component of basement membranes. In the glomerular basement membrane (GBM) of the kidney, the alpha3, alpha4, and alpha5(IV) collagen chains form a distinct network that is essential for the long-term stability of the glomerular filtration barrier, and is absent in most patients affected with Alport syndrome, a progressive inherited nephropathy associated with mutation in COL4A3, COL4A4, or COL4A5 genes. To investigate, in vivo, the regulation of the expression, assembly, and function of the alpha3alpha4alpha5(IV) protomer, we have generated a yeast artificial chromosome transgenic line of mice carrying the human COL4A3-COL4A4 locus. Transgenic mice expressed the human alpha3 and alpha4(IV) chains in a tissue-specific manner. In the kidney, when expressed onto a Col4a3(-/-) background, the human alpha3(IV) chain restored the expression of and co-assembled with the mouse alpha4 and alpha5(IV) chains specifically at sites where the human alpha3(IV) was expressed, demonstrating that the expression of all three chains is required for network assembly. The co-assembly of the human and mouse chains into a hybrid network in the GBM restores a functional GBM and rescues the Alport phenotype, providing further evidence that defective assembly of the alpha3-alpha4-alpha5(IV) protomer, caused by mutations in any of the three chains, is the pathogenic mechanism responsible for the disease. This line of mice, humanized for the alpha3(IV) collagen chain, will also provide a valuable model for studying the pathogenesis of Goodpasture syndrome, an autoimmune disease caused by antibodies against this chain.     

Temporary Health Impact of Prostate MRI and Transrectal Prostate Biopsy in Active Surveillance Prostate Cancer Patients

PurposeTo assess the temporary health impact of prostate multiparametric MRI (mpMRI) and transrectal prostate biopsy in an active surveillance prostate cancer population.MethodsA two-arm institutional review board–approved HIPAA-compliant prospective observational patient-reported outcomes study was performed from November 2017 to July 2018. Inclusion criteria were men with Gleason 6 prostate cancer in active surveillance undergoing either prostate mpMRI or transrectal prostate biopsy. A survey instrument was constructed using validated metrics in consultation with the local patient- and family-centered care organization. Study subjects were recruited at the time of diagnostic testing and completed the instrument by phone 24 to 72 hours after testing. The primary outcome measure was summary testing-related quality of life (summary utility score), derived from the testing morbidities index (TMI) (scale: 0 = death and 1 = perfect health). TMI is stratified into seven domains, with each domain scored from 1 (no health impact) to 5 (extreme health impact). Testing-related quality-of-life measures in the two cohorts were compared with Mann-Whitney U test.ResultsIn all, 122 subjects were recruited, and 90% (110 of 122 [MRI 55 of 60, biopsy 55 of 62]) successfully completed the survey instrument. The temporary quality-of-life impact of transrectal biopsy was significantly greater than that of prostate mpMRI (0.82, 95% confidence interval [CI] 0.79-0.85, versus 0.95, 95% CI 0.94-0.97; P < .001). The largest mean domain-level difference was for intraprocedural pain (transrectal biopsy 2.6, 95% CI 2.4-2.8, versus mpMRI 1.3, 95% CI 1.1-1.5; P < .001).ConclusionTransrectal prostate biopsy has greater temporary health impact (lower testing-related quality-of-life measure) than prostate mpMRI.     

Neonatal Fc Receptor Promotes Immune Complex–Mediated Glomerular Disease

The neonatal Fc receptor (FcRn) is a major regulator of IgG and albumin homeostasis systemically and in the kidneys. We investigated the role of FcRn in the development of immune complex–mediated glomerular disease in mice. C57Bl/6 mice immunized with the noncollagenous domain of the α3 chain of type IV collagen (α3NC1) developed albuminuria associated with granular capillary loop deposition of exogenous antigen, mouse IgG, C3 and C5b-9, and podocyte injury. High-resolution imaging showed abundant IgG deposition in the expanded glomerular basement membrane, especially in regions corresponding to subepithelial electron dense deposits. FcRn-null and -humanized mice immunized with α3NC1 developed no albuminuria and had lower levels of serum IgG anti-α3NC1 antibodies and reduced glomerular deposition of IgG, antigen, and complement. Our results show that FcRn promotes the formation of subepithelial immune complexes and subsequent glomerular pathology leading to proteinuria, potentially by maintaining higher serum levels of pathogenic IgG antibodies. Therefore, reducing pathogenic IgG levels by pharmacologic inhibition of FcRn may provide a novel approach for the treatment of immune complex–mediated glomerular diseases. As proof of concept, we showed that a peptide inhibiting the interaction between human FcRn and human IgG accelerated the degradation of human IgG anti-α3NC1 autoantibodies injected into FCRN-humanized mice as effectively as genetic ablation of FcRn, thus preventing the glomerular deposition of immune complexes containing human IgG.The MHC class I–like neonatal Fc receptor (FcRn), a heterodimer comprising a heavy chain and β₂-microglobulin light chain, is the major regulator of IgG and albumin homeostasis.¹ Perinatally, FcRn mediates the transfer of IgG from mother to offspring, across the placenta in primates and trans-intestinally in suckling rodents. Throughout life, FcRn protects IgG and albumin from catabolism, explaining the unusually long t_1/2 and high serum levels of these proteins. IgG and albumin taken up by cells by pinocytosis bind strongly to FcRn at pH 6.0–6.5 in endosomes. FcRn-bound ligands are then recycled to the plasma membrane, where they dissociate at pH 7.4, whereas IgG and albumin not bound to FcRn are targeted to lysosomes for degradation. FcRn is thought to promote some autoimmune diseases because it protects pathogenic IgG from degradation. For instance, Fcrn^−/− mice are resistant to passive transfer of arthritis by K/BxN sera and autoimmune skin pathology induced by antibodies targeting autoantigens at the dermal–epidermal junction, although this protection can be overcome by excess autoantibodies.^2–4In kidneys, FcRn is expressed in podocytes and proximal tubular epithelial cells.⁵ Overall, renal FcRn reclaims albumin but facilitates elimination of IgG.⁶ Tubular FcRn mediates IgG transcytosis.⁷ Podocytes use FcRn to clear IgG from the glomerular basement membrane (GBM).⁸ IgG accumulates in the glomeruli of aged Fcrn^−/− mice due to impaired clearance of IgG from the GBM, and saturating this clearance mechanism by excess ligand potentiates the pathogenicity of nephrotoxic sera in wild-type mice. Podocyte FcRn has been postulated to be involved in the clearance of immune complexes (ICs) present in pathologic conditions such as membranous nephropathy.⁵ Expression of FcRn in human podocytes is increased in various immune-mediated glomerular diseases.⁹ Given its role in IgG and albumin handling in the kidneys and systemically, FcRn can be expected to influence the development of immune-mediated kidney diseases at multiple levels. This conjecture awaits experimental verification.To determine the role of FcRn in IgG-mediated glomerular disease, we asked how FcRn deficiency alters the course of disease in mice immunized with the NC1 domain of α3 type IV collagen (α3NC1). We chose this antigen because of its reported ability to induce disease in C57Bl/6 (B6) mice,¹⁰ corroborated in pilot studies (Supplemental Figure 1). Fcrn^−/− mice are hypoalbuminemic due to impaired albumin recycling,¹¹ and also exhibit reduced urinary albumin excretion.¹² As a control for this potential confounder, we used FCRN-humanized mice, which have normal serum albumin because human FcRn recycles mouse albumin but not mouse IgG.¹³All mice immunized with α3NC1 developed circulating mouse IgG anti-α3NC1 antibodies, which reached the maximum titer about 6 weeks later and gradually declined thereafter. At all times, the levels of mouse IgG anti-α3NC1 antibodies in sera from Fcrn^−/− mice and FCRN-humanized mice were approximately 50%–70% lower than those in wild-type mouse sera (Figure 1A). The results were similar for mouse IgG1, IgG2b, and IgG2c anti-α3NC1 antibodies (Supplemental Figure 2). Wild-type B6 mice immunized with α3NC1 started developing progressive albuminuria 8–10 weeks later (Figure 1B). By week 14, the urinary albumin creatinine ratio increased approximately 100-fold, and hypoalbuminemia developed (Figure 1C). Urinary albumin excretion in Fcrn^−/− mice and FCRN-humanized mice immunized with α3NC1 was not significantly higher than in adjuvant-immunized control mice. No mice developed renal failure (Supplemental Figure 3).Open in a separate windowFigure 1.FcRn ablation reduces serum levels of mouse IgG anti-α3NC1 antibodies and prevents the development of albuminuria in α3NC1-immunized mice. (A) The left panel shows circulating mIgG anti-α3NC1 antibodies from C57Bl6 wild-type mice (○), Fcrn^−/− mice (□), FCRN-humanized (hFCRN) mice (◇), and the control CFA group (△), which are assayed by indirect ELISA in plates coated with α3NC1 (100 ng/well). Mouse sera are diluted 1:5000. The right panel shows the significance of circulating mIgG anti-α3NC1 antibody differences among groups at week 12, as assessed by one-way ANOVA followed by Bonferroni post tests for pairwise comparisons. (B) The left panel shows that the urinary albumin creatinine ratio (mean±SEM) time course is monitored in C57Bl6 wild-type mice (○), Fcrn^−/− mice (□), and hFCRN mice (◇) immunized with α3NC1 (n=5–8 mice in each group, from two separate experiments). Mice in the control group (△) are immunized with adjuvant alone (n=9). The right panel shows the urinary albumin creatinine ratio (mean±SEM) at 14 weeks, when mice are euthanized. The significance of differences among groups is assessed by one-way ANOVA followed by Bonferroni post tests for pairwise comparisons. (C) The left panel shows SDS-PAGE analysis of serum (0.5 µl/lane) and urine samples (2 µl/lane) from CFA-immunized control mice (a) and α3NC1-immunized wild-type mice (b), Fcrn^−/− mice (c), and hFCRN mice (d) collected at week 14. The right panel presents a densitometric analysis of the relative levels of albumin in mouse serum samples showing that α3NC1-immunized wild-type mice developed hypoalbuminemia. *P<0.05 by two-tailed t test versus CFA-immunized wild-type mice; **P<0.01; ***P<0.001. ns, not significant; WT, wild type.At 14 weeks after α3NC1 immunization, kidneys examined by light microscopy showed mild glomerular pathology, with few crescents and relatively little inflammation (Figure 2A), similar to α3NC1-immunized DBA/1 mice with comparable albuminuria.^14,15 Electron microscopy showed extensive subepithelial IC deposits surrounded by an expanded GBM and effacement of podocyte foot processes in α3NC1-immunized B6 mice, whereas Fcrn^−/− mice had fewer subepithelial deposits (Figure 2B, Supplemental Figure 4). Immunofluorescence staining showed granular capillary loop deposition of mouse IgG, exogenous antigen, C3, and C5b-9, more intense in wild-type mice than in Fcrn^−/− mice and FCRN-humanized mice (Figure 2, Ca–Cp, Supplemental Figure 5). A loss of nephrin staining, indicative of podocyte injury, occurred in α3NC1-immunized B6 mice but not in Fcrn^−/− mice or FCRN-humanized mice (Figure 2, Cq–Ct).Open in a separate windowFigure 2.FcRn deficiency reduces formation of pathogenic subepithelial ICs. (A) Light microscopic evaluation of kidneys from adjuvant-immunized control mice (a) and α3NC1-immunized wild-type mice (b) and Fcrn^−/− mice (c) revealed few pathogenic changes and the absence of glomerular inflammation (periodic acid–Schiff staining). (B) Transmission electron microscopy shows normal GBM (arrow) and podocyte foot processes in control mice (a), extensive subepithelial electron dense deposits (arrowhead), thickened GBM, and podocyte foot process effacement in α3NC1-immunized wild-type mice (b), and fewer IC deposits in the Fcrn^−/− mice (c). (C) Immunofluorescence analysis of kidneys from adjuvant-immunized control mice (a, e, i, m, and q) and α3NC1-immunized wild-type mice (b, f, j, n, and r), FcRn^−/− mice (c, g, k, o, and s), and hFCRN mice (d, h, l, p, and t) evaluate the deposition of mouse IgG (a–d), exogenous α3NC1 antigen stained by mAb RH34 (e–h), mouse C3c (i–l), C5b-9 (m–p), and nephrin staining (q–t) at 14 weeks. Wild-type mice exhibit linear-granular GBM deposition of mouse IgG and granular GBM deposition of exogenous antigen, C3, and C5b-9, which are attenuated in Fcrn^−/− mice and hFCRN mice and essentially absent in control mice. Compared with control mice, α3NC1-immunized wild-type mice but not Fcrn^−/− or hFCRN mice exhibit a loss of nephrin staining, indicative of podocyte injury. WT, wild type; EM, electron microscopy, PAS, periodic acid–Schiff. Original magnification, ×400 in A; ×2850 in B; ×200 in C.Because B6 mice immunized with bovine GBM NC1 hexamers have normal kidney function and histology despite linear GBM deposition of IgG autoantibodies binding to mouse α345(IV) collagen (Supplemental Figure 1), the question arises as to what causes proteinuria in α3NC1-immunized mice. Because the clinical presentation, morphology, and effector mechanisms depend on where ICs are localized in the capillary wall, we compared IgG distribution in α3NC1-immunized mice and mice injected with anti-α3NC1 antibodies modeling anti-GBM autoantibodies. The distribution and relative abundance of mouse IgG, as imaged by immunoperoxidase immunoelectron microscopy and stochastic optical reconstruction microscopy (STORM), a method for super-resolution fluorescence microscopy, were concordant. In α3NC1-immunized mice, IgG deposition was abundant in the areas of expanded GBM and especially in regions corresponding to the subepithelial dense deposits seen by routine electron microscopy. By contrast, in mice injected with α3NC1-specific anti-GBM mAb, the IgG was confined to an ultrastructurally normal GBM that lacked subepithelial deposits (Figure 3).Open in a separate windowFigure 3.Localization of IgG by high-resolution imaging. The localization of mouse IgG in glomerular capillary walls of wild-type mice immunized with α3NC1 (A, C–E), or intravenously injected with anti-mouse α3NC1 IgG mAb 8D1 (B, F–H) is determined by immunoperoxidase electron microscopy (A and B) and STORM imaging (C–H). In A, the GBM is irregularly thickened, and abundant electron dense peroxidase reaction product is present in discontinuous, subepithelial patterns beneath broadly effaced podocyte foot processes (arrows). In B, the peroxidase reaction product is diffusely present throughout the GBM (arrowhead), but less abundant compared with A. Electron dense deposits are absent, and podocyte foot process architecture appears normal. (C–E) By STORM imaging, anti-agrin (blue) identifies both normal and thickened areas of the GBM, both of which contain dense accumulations of mouse IgG throughout (red). The electron microscopy correlation in E shows GBM staining with respect to the podocytes and endothelial cells. (F–H) IgG mAb 8D1 (red) is present in the GBM, which shows no evidence of thickening. CL, capillary lumen; EM, electron microscopy En, endothelium;Po, podocyte.Subepithelial ICs, a hallmark of human membranous nephropathy (MN), form when IgG antibodies bind to podocyte antigens, such as phospholipase A2 receptor (PLA2R) and neutral endopeptidase (NEP), or to planted antigens, such as cationic BSA.^16–18 Subsequent expansion of the GBM, complement activation, and podocyte injury by C5b-9 cause proteinuria. Although it is unexpected, formation of subepithelial ICs in α3NC1-immunized mice may be explained by exogenous α3NC1 deposited in glomeruli acting as a planted antigen.¹⁹ Alternatively, anti-α3NC1 antibodies in complex with α3NC1 antigen may act as surrogate antipodocyte antibodies, because α3NC1-containing ICs bind to podocytes.²⁰ After four immunizations with α3NC1 monomers, B6 mice and DBA/1 mice eventually develop crescentic GN by 26 and 10 weeks, respectively.^10,14 The combination of subepithelial ICs and crescentic anti-GBM antibody GN was most recently described in a series of eight patients with circulating anti-α3NC1 autoantibodies but undetectable anti-PLA2R autoantibodies.²¹In contrast to wild-type B6 mice, congenic Fcrn^−/− mice and FCRN-humanized mice did not develop albuminuria after α3NC1 immunization. Their resistance to proteinuria was associated with lower serum titers of anti-α3NC1 IgG antibodies and reduced glomerular deposition of IgG, antigen, C3, and C5b-9. Because C5b-9 is an essential mediator of podocyte damage and proteinuria by subepithelial ICs,^22,23 reduced complement activation potentially explains the attenuated glomerular pathology in FcRn-deficient mice. The resistance of FCRN-humanized mice indicates that FcRn promotes IC-mediated glomerular disease due to its interaction with IgG rather than albumin. We propose that FcRn promotes the development of subepithelial ICs and subsequent glomerular injury primarily by maintaining higher serum levels of pathogenic IgG (Supplemental Figure 6). However, we cannot formally exclude a possible pathogenic role of podocyte FcRn, whose stimulation by ICs may induce maladaptive signaling.⁹ Future studies in mice with podocyte-specific ablation of FcRn would address this possibility.Our findings identify FcRn as a potential target for therapeutic intervention in IC-mediated glomerular diseases, typically treated with nonspecific immunosuppressants that are toxic and sometimes ineffective. More specific therapies include ablation of B cells by rituximab. In patients with idiopathic MN who respond to rituximab therapy, serum levels of anti-PLA2R IgG autoantibodies decline over a period of many months, and their disappearance is followed by resolution of proteinuria.²⁴ The slow decline in proteinuria is problematic for patients already suffering from complications of nephrotic syndrome, who would benefit from ancillary therapies that reduce pathogenic IgG antibodies more rapidly. This may be achieved by inhibiting FcRn.One implementation of this concept is therapy with high-dose intravenous Ig (HD-IVIG). HD-IVIG accelerates the degradation of IgG by saturating FcRn,²⁵ one of the mechanisms that explain the beneficial effects of HD-IVIG therapy in some autoimmune diseases.³ In pregnant women with circulating anti-NEP alloantibodies mediating antenatal MN, treatment with HD-IVIG reduces the titers of IgG alloantibodies by approximately 30% within 2–3 weeks.²⁶ However, HD-IVIG is inefficient, because large amounts of IgG (1–2 g/kg) cause relatively modest reductions in pathogenic IgG titers. Specific FcRn inhibitors recapitulate this activity of HD-IVIG more effectively at lower doses. By reducing pathogenic IgG levels, function-blocking anti-FcRn mAbs ameliorate experimental myasthenia gravis in rats,²⁷ and engineered IgG “Abdegs” that bind with high affinity to FcRn ameliorate arthritis transferred by K/BxN serum.²⁸To assess the translational potential of our findings, we asked whether pharmacologic blockade of human FcRn can reproduce the effects of genetic FcRn deficiency. To this end, FCRN-humanized and Fcrn^−/− mice were passively immunized with human IgG containing anti-α3NC1 (Goodpasture) autoantibodies. To inhibit human FcRn, we used a lysine analog of SYN1436 (Figure 4A),²⁹ a peptide that binds with subnanomolar affinity to human FcRn, thus preventing IgG binding.³⁰ In vivo, SYN1436 reduces IgG levels in cynomolgus monkeys by 80%.³⁰ Serum anti-α3NC1 autoantibodies in FCRN-humanized mice treated with anti-FcRn peptide, but not with control peptide, sharply decreased to the same levels as in Fcrn^−/− mice (Figure 4B), and were no longer detected after 4 days. In mice, human IgG elicits murine anti-human IgG antibodies, forming ICs that can deposit in glomeruli, as shown in active serum sickness models. Glomerular deposition of ICs containing human IgG was abolished in mice treated with anti-FcRn peptide, but not with control peptide (Figure 4C). Linear GBM deposition of human anti-GBM IgG was not observed, because the epitopes recognized by Goodpasture autoantibodies are completely inaccessible in the mouse GBM.³¹ These results provide proof of concept that therapies targeting human FcRn effectively lower serum levels of pathogenic human IgG autoantibodies, which could be beneficial in patients with IgG-mediated kidney diseases. Because FcRn also mediates the trans-placental transfer of IgG from mother to the fetus, FcRn inhibition may be particularly attractive for preventing antenatal MN caused by maternal anti-NEP alloantibodies.Open in a separate windowFigure 4.Pharmacologic blockade of human FcRn accelerates the catabolism of human IgG autoantibodies in FCRN-humanized mice. (A) Structure of a peptide that binds with high affinity to human FcRn, competitively inhibiting its interaction with human IgG (top). The control peptide (bottom) containing D-amino acids does not bind to human FcRn. Pen, Sar, and NMeLeu denote penicillamine, sarcosine, and N-methyl-leucine, respectively. (B) Serum level of human IgG anti-α3NC1 antibodies in FCRN-humanized mice treated with anti-FcRn peptide (▪) or control peptide (●) and in Fcrn^−/− (▲) mice sera (n=3 in each group) is analyzed by indirect ELISA in plates coated with α3NC1 (100 ng/well). Mouse sera are diluted 1:500. (C) Kidney deposition of human IgG (a and b) and mouse IgG (c and d) in FCRN-humanized mice treated with control peptide (a and c) or anti-FcRn peptide (b and d) is evaluated by direct immunofluorescence staining. Treatment with anti-FcRn peptide prevents the glomerular deposition of ICs containing human IgG.     

Morphologic and clinical correlations in medullar thymoma

The medullar thymoma is a rare and distinctive epithelial thymoma, a thymic tumor characterized histologically by a mixture of spindle epithelial cells and lymphoid cells. We are presenting this tumor to a 68 years old man, admitted at CCI, for a mediastinal tumor, treated by tumorectomy, for revealing the cytological, histological and immunohistochemical characteristic features. The surgical biopsy was prepared by using usual histological techniques and haematoxilin eosin and Van Gieson stainings. We are discussing the relation between the thymoma clinicopathological and prognostic features, resulting a clear correlation between histological type and clinical study. We also pointed the Muller-Hermelink thymoma histological subtypes and their correspondence with OMS histological types, reflecting realistically the thymoma clinical behavior.     

Glomerular injury is exacerbated in diabetic integrin alpha1-null mice

Excessive glomerular collagen IV and reactive oxygen species (ROS) production are key factors in the development of diabetic nephropathy. Integrin alpha1beta1, the major collagen IV receptor, dowregulates collagen IV and ROS production, suggesting this integrin might determine the severity of diabetic nephropathy. To test this possibility, wild-type and integrin alpha1-null mice were rendered diabetic with streptozotocin (STZ) (100 mg/kg single intraperitoneal injection), after which glomerular filtration rate (GFR), glomerular collagen deposition, and glomerular basement membrane (GBM) thickening were evaluated. In addition, ROS and collagen IV production by mesangial cells as well as their proliferation was measured in vitro. Diabetic alpha1-null mice developed worse renal disease than diabetic wild-type mice. A significant increase in GFR was evident in the alpha1-null mice at 6 weeks after the STZ injection; it started to decrease by week 24 and reached levels of non-diabetic mice by week 36. In contrast, GFR only increased in wild-type mice at week 12 and its elevation persisted throughout the study. Diabetic mutant mice also showed increased glomerular deposition of collagen IV and GBM thickening compared to diabetic wild-type mice. Primary alpha1-null mesangial cells exposed to high glucose produced more ROS than wild-type cells, which led to decreased proliferation and increased collagen IV synthesis, thus mimicking the in vivo finding. In conclusion, this study suggests that lack of integrin alpha1beta1 exacerbates the glomerular injury in a mouse model of diabetes by modulating GFR, ROS production, cell proliferation, and collagen deposition.     

Urologist Practice Affiliation and Intensity-modulated Radiation Therapy for Prostate Cancer in the Elderly

Background

Prostate cancer treatment is a significant source of morbidity and spending. Some men with prostate cancer, particularly those with significant health problems, are unlikely to benefit from treatment.

Corrosion inhibitors from expired drugs

This paper presents a method of expired or unused drugs valorization as corrosion inhibitors for metals in various media. Cyclic voltammograms were drawn on platinum in order to assess the stability of pharmaceutically active substances from drugs at the metal-corrosive environment interface. Tafel slope method was used to determine corrosion rates of steel in the absence and presence of inhibitors. Expired Carbamazepine and Paracetamol tablets were used to obtain corrosion inhibitors. For the former, the corrosion inhibition of carbon steel in 0.1 mol L(-1) sulfuric acid solution was about 90%, whereas for the latter, the corrosion inhibition efficiency of the same material in the 0.25 mol L(-1) acetic acid-0.25 mol L(-1) sodium acetate buffer solution was about 85%.     

Th1 and Th17 Cells Induce Proliferative Glomerulonephritis

Th1 effector CD4+ cells contribute to the pathogenesis of proliferative and crescentic glomerulonephritis, but whether effector Th17 cells also contribute is unknown. We compared the involvement of Th1 and Th17 cells in a mouse model of antigen-specific glomerulonephritis in which effector CD4+ cells are the only components of adaptive immunity that induce injury. We planted the antigen ovalbumin on the glomerular basement membrane of Rag1^−/− mice using an ovalbumin-conjugated non-nephritogenic IgG1 monoclonal antibody against α3(IV) collagen. Subsequent injection of either Th1- or Th17-polarized ovalbumin-specific CD4+ effector cells induced proliferative glomerulonephritis. Mice injected with Th1 cells developed progressive albuminuria over 21 d, histologic injury including 5.5 ± 0.9% crescent formation/segmental necrosis, elevated urinary nitrate, and increased renal NOS2, CCL2, and CCL5 mRNA. Mice injected with Th17 cells developed albuminuria by 3 d; compared with Th1-injected mice, their glomeruli contained more neutrophils and greater expression of renal CXCL1 mRNA. In conclusion, Th1 and Th17 effector cells can induce glomerular injury. Understanding how these two subsets mediate proliferative forms of glomerulonephritis may lead to targeted therapies.Although proliferative and crescentic glomerulonephritides occur in different primary renal diseases and are an important component of several systemic diseases, features of human renal biopsies suggest some common effector pathways. In most cases of rapidly progressive GN there is evidence for an important role for cellular immune effectors: T cells, macrophages, and neutrophils,^1–3 a role confirmed in animal models.^4–7 CD4+ T cells are key components of renal injury.^4,8 When activated, CD4+ cells tend to differentiate into subsets (T helper cells—Th1, Th2 and Th17) that engage immune effectors in different ways. In proliferative forms of GN, T cells direct adaptive immune responses that drive glomerular disease, but also, in rapidly progressive GN, CD4+ cells themselves accumulate in glomeruli as effectors. These effector T helper cells activate innate effector cells, predominantly neutrophils and macrophages, and activate and damage intrinsic renal cells.In GN, the variable Th1-Th2 predominance of responses influences the histologic patterns and severity of GN.⁹ Th1 cells, which secrete IFNγ and activate macrophages, are important in some forms of experimental proliferative GN. Th2 cells, characterized by IL-4 production, promote humoral immunity and are important in several forms of GN, but there is little evidence that Th2 cells play primary roles as effector cells within glomeruli in rapidly progressive GN. A binary Th1/Th2 model explains many of the differences in the patterns of immune responses in GN. However, there are discrepancies¹⁰ that might be explained by defining a role for a third major subset, Th17 cells, characterized by the production of IL-17A. Its biology has recently been comprehensively reviewed.¹¹ Th17 subset effects potentially relevant to rapidly progressive GN include direct effects on neutrophils and stimulating the production of neutrophil chemoattractants by tissue cells. Thus, in most rapidly progressive types of GN, cell-mediated injury, a key component of injury, may be directed by the Th17 subset, the Th1 subset, or both subsets.Although antigen-specific T cells are critical to adaptive immune responses, the cells themselves are relatively infrequent. T cell receptor (TcR) transgenic mice help define the contributions of different antigen-specific T helper cell subsets in organ-specific disease.^12–14 In the studies presented here we have established a new antigen-specific model of GN. Ovalbumin (OVA)-specific OT-II TcR transgenic CD4+ cells¹⁵ are polarized ex vivo under Th1- or Th17-inducing conditions. Effector cells are transferred into recombination activating gene-1 deficient (Rag1^−/−) mice with OVA planted in their glomeruli by injecting an OVA conjugate. OVA is conjugated to a mouse IgG1 mAb binding to α3(IV) collagen in murine glomerular basement membrane (GBM). The mAb-OVA conjugate dose is capable of planting significant OVA in glomeruli as an antigen to induce effector responses, but is insufficient to induce significant histologic or functional injury as an antibody. This model allows us to understand effector CD4+ T cell and Th subset-induced injury, with no effects from CD8+ cells or B cells.CD4+ cells, isolated from OVA-specific TcR transgenic (OT-II) mice and cultured under Th1 or Th17 priming conditions (see Concise Methods), were confirmed to be Th1 or Th17 by cytokine production before transfer. Th1 polarized cells expressed IFNγ, whereas no IL-17A or IL-4 production was detected (Figure 1A). Th17 polarized cells were strong IL-17A producers, showing only weak IFNγ production, with >20% of cells producing IL-17A, but few IFNγ or double-positive cells (Figure 1B). To plant OVA in glomeruli, the mAb 8D1, a non-nephritogenic, murine IgG1 binding to mouse α3(IV)NC1,¹⁶ was conjugated to OVA and purified by size-exclusion chromatography so that no free OVA or unconjugated 8D1 mAb remained, confirmed by Western blotting (Figure 1C). Antigen-specific CD4+ cells recognized OVA bound to the 8D1 anti-GBM mAb. Culture of CFSE-labeled naive OT-II cells incubated with the 8D1-OVA conjugate enhanced their survival (30% to 40% survival after 72 h versus 5% to 6% with unconjugated antibody) and induced OT-II cell proliferation (72 h: 27% of cells, up to 4 cycles, Figure 1D). OT-II cells incubated with unconjugated 8D1 did not proliferate (Figure 1E). After intravenous injection, 8D1-OVA conjugates bound to the GBM in a linear manner; no fluorescence signal was observed after transfer of Th1 cells without 8D1-OVA (Figure 1G). Western blotting showed OVA in the kidney after injection of 8D1-OVA conjugate (Figure 1H). Lungs from 8D1-OVA-injected mice were weakly positive for mouse IgG, whereas no IgG was detected in the spleen or liver (detecting antibody titer 1:100) 3 or 21 d after injection. Mouse IgG was not detected in sera (ELISA, dilution 1:100) at day 3 or day 21. As expected (given the transfer of only CD4+ cells to Rag1^−/− mice), no anti-OVA antibodies in sera were detected in recipient mice (data not shown).Open in a separate windowFigure 1.Differentiation of OVA-specific OT-II Th1 and Th17 cells, antibody-OVA conjugation, glomerular IgG and intrarenal OVA detection, and recipient immune responses after cell transfer. (A) After stimulating naive OT-II cells with OVA in a Th1 environment, IFNγ was produced and intracellular cytokine staining of CD4+ cells demonstrated strong IFNγ staining with minimal IL-17A or IL-4. (B) Culturing cells in a Th17-stimulating environment led to strong IL-17A production, whereas cells stained positive for IL-17A but not IL-4, and only 2% of cells produced IFNγ. (C) Chromatographic profile of 8D1-OVA conjugation. The numbers 1 to 7 represent fractions collected for analyses by Western blotting, which confirmed that all OVA-conjugated fractions contained OVA and IgG (lanes 1–6), whereas unconjugated fractions (represented as “Un”) contained IgG alone. The lane labeled “M” contained molecular weight markers. (D and E): 8D1-OVA was recognized by OT-II cells because multiple cycles of proliferation of cultured naive OT-II cells (D) were seen with 8D1-OVA conjugate and (E) not seen with unconjugated antibody. Strong linear IgG staining of glomeruli was seen after (F) the administration of 8D1-OVA to Rag1^−/− mice, but not after (G) the injection of Th1 cells without antibody. Western blotting of homogenized kidney (H) 24 h after the administration of 8D1-OVA demonstrated OVA in the kidneys (labeled as OVA-Ab); this was not seen after the administration of unconjugated antibody (labeled as Un Ab). (I) Systemic immune responses of recipient Rag1^−/− mice at 21 d assessed by splenic cytokine production demonstrated enhanced IFNγ production in mice given 8D1-OVA and Th1 cells, with enhanced IL-17A production by mice receiving 8D1-OVA and Th17 cells. (J) DTH to OVA (at 21 d) was induced only in mice given 8D1-OVA and Th1 cells. *P < 0.05, ***P < 0.001.To determine whether transfer of either Th1 or Th17 antigen-specific effector cells induces glomerular injury, 8D1-OVA conjugate was administered intravenously to Rag1^−/− mice (lacking adaptive immunity). Three hours later, 5 × 10⁶ Th1 or Th17 cells were injected intravenously. Groups of mice injected with 8D1-OVA alone (without cells) or Th1 cells alone (without 8D1-OVA) served as controls. At 21 d, the injected T cells largely maintained their initial phenotype, because host splenocytes from mice given Th1 cells showed enhanced OVA-stimulated IFNγ production whereas IL-17A production was enhanced in mice given Th17 cells (Figure 1I). Dermal-delayed-type hypersensitivity (DTH) was induced by footpad injection of OVA and measured after 24 h. Only mice that received the 8D1-OVA conjugate and Th1 polarized cells developed dermal DTH (Figure 1J), a classical Th1 response.¹⁷After planting OVA in glomeruli, administration of Th1 or Th17 cells induced glomerular disease. Urinary albumin excretion was not increased in mice given 8D1-OVA conjugate alone or Th1 cells alone, but Th1 or Th17 cells with 8D1-OVA induced significant albuminuria (Figure 2A). Albuminuria was consistent throughout the time course of the study in the Th17 group, whereas in the Th1 group there was a progressive increase in albuminuria until day 21 (Figure 2B). Control mice given Th1 cells alone or the 8D1-OVA conjugate alone exhibited only mild histologic changes (no crescent formation, fibrinoid necrosis, or hyalinosis). Analysis of histologic injury demonstrated substantially more abnormal glomeruli in the mice given 8D1-OVA conjugate with Th1 or Th17 cells compared with control groups (Figure 2C). Th1 and Th17 (+8D1-OVA) recipients developed proliferative GN, [glomerular hypercellularity: 8D1-OVA and Th1 cells: 32.1 ± 1.0 cells/glomerular cross section (c/gcs), 8D1-OVA and Th17 cells: 29.8 ± 1.1 c/gcs, 8D1-OVA alone: 21.3 ± 0.2 c/gcs, Th1 cells alone: 18.9 ± 2.0 c/gcs; P < 0.001]. Representative kidney sections from each group are shown (Figure 2, D through G). Crescent formation and fibrinoid necrosis, although seen in only a few glomeruli, was observed exclusively in mice given 8D1-OVA conjugate and Th1 cells (5.5 ± 0.9% at day 21; Figure 2, H and I). No crescent formation was observed in mice receiving 8D1-OVA conjugate and Th17 cells. Mice did not develop significant renal impairment (measured by BUN; data not shown).Open in a separate windowFigure 2.Renal injury in mice injected with 8D1-OVA conjugate, then either Th1 or Th17 cells. (A) Mice given 8D1-OVA conjugate or Th1 cells alone did not develop albuminuria above values for noninjected Rag1^−/− mice (dotted line). At 21 d, albuminuria was increased in mice given 8D1-OVA and Th1 cells or 8D1-OVA and Th17 cells. (B) In mice given 8D1-OVA and Th17 cells, albuminuria had plateaued by day 7 and did not progress. In mice given 8D1-OVA and Th1 cells there was a progressive rise in albuminuria. (C) Histologic injury was significant in mice given 8D1-OVA and either Th1 or Th17 cells. Representative glomeruli from mice given (D) 8D1-OVA alone, (E) Th1 cells alone, (F) 8D1-OVA and Th1 cells, and (G) 8D1-OVA and Th17 cells are shown. (H and I) Crescentic injury and fibrinoid necrosis were only seen in mice given 8D1-OVA and Th1 cells. ***P < 0.001Recruitment and activation of leukocyte subpopulations differed in mice administered Th1 or Th17 cells (Figure 3A). Although glomerular CD4+ cell and macrophage numbers were similarly increased in mice given 8D1-OVA conjugate and either Th1 or Th17 cells at day 21, more neutrophils were found in mice given 8D1-OVA and Th17 cells compared with mice given 8D1-OVA and Th1 cells. Interstitial leukocyte infiltrates followed a similar pattern (Figure 3B). Consistent with the finding of increased neutrophils in kidneys of mice receiving Th17 cells, renal mRNA expression of the primary neutrophil attracting chemokine CXCL1 was elevated (Figure 3C). Th17 cells attract neutrophils¹⁸ and in vitro studies have shown that neutrophil recruitment is achieved via production of CXCL8, the human homologue of CXCL1, by Th17 cells.¹⁹ It is therefore likely that at least some of the Th17-induced renal injury is mediated by neutrophils. In mice receiving 8D1-OVA and Th1 cells, macrophages were likely to be more activated; only these mice developed dermal DTH and increased expression of mRNA for the macrophage chemoattractants CCL2 and CCL5 (Figure 3, D and E), which have been associated with experimental crescentic GN.²⁰ Furthermore, type 2 nitric oxide synthase (NOS2/iNOS) mRNA, a marker of macrophage activation²¹ and urinary nitrate, a marker of intrarenal macrophage NOS2 production, were increased in this group (Figure 3, F and G).Open in a separate windowFigure 3.Leukocytes in kidneys of mice with either Th1- or Th17-induced injury 21 d after cell transfer. (A) Glomerular CD4+T cells, neutrophils, and macrophages were increased in mice given 8D1-OVA and Th1/Th17 cells. Neutrophil recruitment was incrementally increased in mice given 8D1-OVA and Th17 cells compared with 8D1-OVA and Th1 cells. (B) A similar pattern of recruitment was seen in the cortical interstitium. Renal chemokine mRNA expression demonstrated (C) enhanced CXCL1 mRNA in mice given 8D1-OVA and Th17 cells, whereas (D) CCL2 and (E) CCL5 were increased in mice given 8D1-OVA and Th1 cells. (F and G) NOS2 and urinary nitrate, markers of macrophage activation, were increased in mice receiving 8D1-OVA and Th1 cells. For mRNA, values for the 8D1-OVA alone group are presented as 1. *P < 0.05, **P < 0.01, ***P < 0.001.Further studies were performed 3 d after cell transfer. At this time point, albuminuria was present in mice receiving 8D1-OVA conjugate and Th17 cells, but not 8D1-OVA conjugate and Th1 cells (Figure 4A), and a higher proportion of glomeruli were abnormal in mice that had received Th17 cells (Figure 4B). Therefore, Th17-induced glomerular injury occurred earlier than Th1-induced injury. Leukocytes were present in glomeruli (Figure 4C) with increased numbers of neutrophils in glomeruli of mice receiving Th17 cells (compared with Th1 cell recipients), whereas Th1 cell recipients exhibited more macrophages. At day 3, these findings were glomerulo-specific; differences between Th1 and Th17 cell recipients were not seen in the interstitium (Figure 4D).Open in a separate windowFigure 4.Renal disease in mice 3 d after injection with 8D1-OVA and either Th1 or Th17 cells. (A) Pathologic albuminuria (dotted line represents values for noninjected Rag1^−/− mice) and (B) increased numbers of abnormal glomeruli were evident in mice that received 8D1-OVA and Th17 cells. (C) Leukocyte recruitment to glomeruli demonstrated CD4+ cells (more in mice receiving Th1 cells), with comparatively more neutrophils in glomeruli of Th17 cell recipients and more macrophages in glomeruli of Th1 cell recipients. (D) Interstitial leukocytes were similar in Th1 and Th17 cell recipients 3 d after cell transfer. *P < 0.05, **P < 0.01, ***P < 0.001.These studies used Rag1^−/− mice as recipients of effector antigen-specific Th1 or Th17 cells. Because these mice do not possess T or B cells, OVA planted in glomeruli cannot induce CD8+ or B cell responses, and regulatory T cells are unable to influence the pattern of injury. A major advantage of this strategy is that Th1- and Th17-mediated injury can be assessed in a pure experimental system. However, T cells transferred into Rag1^−/− mice can undergo homeostatic expansion, and it is possible that the transferred Th1 cells might have expanded more rapidly than Th17 cells. Recently, studies in experimental type 1 diabetes induced by transfer of cells from a TcR transgenic mouse specific for an islet autoantigen showed conversion of Th17 cells to a Th1 phenotype after transfer.^22,23 Although our Th17 polarized OT-II cells, specific for a foreign antigen, showed some IFNγ production after 21 d, they were still capable of producing IL-17A. Furthermore, dermal DTH and renal disease were different in Th1 recipients compared with the Th17 recipients at 21 d, supporting the maintenance of separate phenotypes after transfer. Although the studies presented here are the first to demonstrate a role for Th17 and Th1 cells in the same experimental system, other studies^24–26 have used genetically deficient mice to implicate Th17 cells in experimental renal disease.These studies describe a novel model of cell-mediated proliferative GN for which adaptive components are only effector antigen-specific CD4+ T cells. They demonstrate that both Th1 and Th17 cells can induce proliferative GN. Th17 cells induce albuminuria early, with persistent accumulation of leukocytes. Administration of Th1 cells lead to a slower rise in albuminuria, but more macrophage activation and DTH-like injury, including, in some glomeruli, crescent formation and fibrinoid necrosis. It is likely that Th1 and Th17 responses play a role in proliferative forms of GN and both represent potential therapeutic targets.