Toll-like receptor 3 in viral pathogenesis: friend or foe?

Viral infections frequently induce acute and chronic inflammatory diseases, yet the contribution of the innate immune response to a detrimental host response remains poorly understood. In virus‐infected cells, double‐stranded RNA (dsRNA) is generated as an intermediate during viral replication. Cell necrosis (and the release of endogenous dsRNA) is a common event during both sterile and infectious inflammatory processes. The discovery of Toll‐like receptor 3 (TLR3) as an interferon‐inducing dsRNA sensor led to the assumption that TLR3 was the master sentinel against viral infections. This simplistic view has been challenged by the discovery of at least three members of the DExd/H‐box helicase cytosolic sensors of dsRNA that share with TLR3 the Toll–interleukin‐1 receptor (TIR) ‐adapter molecule TIR domain‐containing adaptor protein interferon‐β (TRIF) for downstream type I interferon signalling. Data are conflicting on the role of TLR3 in protective immunity against viruses in the mouse model. Varying susceptibility to infection and disease outcomes have been reported in TLR3‐immunodeficient mice. Surprisingly, the susceptibility to develop herpes simplex virus‐1 encephalitis in humans with inborn defects of the TLR3 pathway varies, and TLR3‐deficient humans do not show increased susceptibility to other viral infections. Therefore, a current challenge is to understand the protective versus pathogenic contribution of TLR3 in viral infections. We review recent advances in the identification of TLR3‐signalling pathways, endogenous and virus‐induced negative regulators of the TLR3 cascade, and discuss the protective versus pathogenic role of TLR3 in viral pathogenesis.     

Spontaneous regression of cystic dysplasia of the rete testis in an 18-month-old boy: the key role of ultrasonography

Cystic dysplasia of the rete testis (CDT) is a rare cause of scrotal swelling in children. It is a congenital disorder and it can be associated with other genitourinary abnormalities. At present, there is no clear consensus on treatment. Surgical approach has traditionally been the treatment of choice, while, more recently, conservative approach has been applied, justified by the benign nature of the lesion and after few cases of spontaneous regression have been documented. Ultrasonography, supported by negative tumor markers, plays a key role in the diagnostic work up and during observational follow-up. We report a further case of spontaneous regression of suspected CDT in an 18-month-old boy, who has been followed with clinic and ultrasonographic checks.     

Thalamo-cortical networks in subtypes of migraine with aura patients

BackgroundWe searched for differences in resting-state functional connectivity (FC) between brain networks and its relationship with the microstructure of the thalamus between migraine with pure visual auras (MA), and migraine with complex neurological auras (MA+), i.e. with the addition of at least one of sensory or language symptom.Methods3T MRI data were obtained from 20 patients with MA and 15 with MA + and compared with those from 19 healthy controls (HCs). We collected resting state data among independent component networks. Diffusivity metrics of bilateral thalami were calculated and correlated with resting state ICs-Z-scores.ResultsAs compared to HCs, both patients with MA and MA + disclosed disrupted FC between the default mode network (DMN) and the right dorsal attention system (DAS). The MA + subgroup had lower microstructural metrics than both HCs and the MA subgroup, which correlated negatively with the strength of DMN connectivity. Although the microstructural metrics of MA patients did not differ from those of HCs, these patients lacked the correlation with the strength of DAS connectivity found in HCs.ConclusionsThe present findings suggest that, as far as MRI profiles are concerned, the two clinical phenotypes of migraine with aura have both common and distinct morpho-functional features of nodes in the thalamo-cortical network.     

Percutaneous unprotected left main angioplasty with drug-eluting stents in a nonagenarian: feasible and safe despite recurrent restenosis

The management of severe coronary artery disease in the very elderly is challenging and the most appropriate revascularization strategy highly debated. To date, coronary artery bypass surgery has been the treatment of choice for significant stenosis of unprotected left main (ULM) coronary. Whether this holds true also in very old patients is unknown. The Authors hereby report the case of a 91-year-old diabetic man who underwent coronary angiography in June 2005 for subacute unstable angina. Angiography disclosed a critical stenoses in the distal unprotected left main, left anterior descending, and distal left circumflex, which were treated with a paclitaxel-eluting stent and a bare-metal stent (BMS), respectively. Four months later, recurrent angina lead to a second angiography which showed critical restenosis in the left anterior descending and significant ostial stenosis in the left circumflex. Another paclitaxel-eluting stent was implanted in the left anterior descending, followed by kissing balloon in the left main, achieving a good angiographic result. Six months later angina recurred again: at angiography diffuse restenosis in the left main, left anterior descending and left circumflex was documented. A crushing technique was thus employed to deliver 2 sirolimus-eluting stents, achieving a satisfactory final result. Since then, and to date for more than 17 months since the last procedure, this nonagenarian has remained free from anginal chest. This case highlights the potentials and drawbacks of percutaneous coronary intervention for unprotected left main disease, suggesting nonetheless, that this revascularization strategy can be safely repeated even in elderly patients.     

Brentuximab vedotin as salvage treatment in Hodgkin lymphoma naïve transplant patients or failing ASCT: the real life experience of Rete Ematologica Pugliese (REP)

Brentuximab vedotin (BV) shows a high overall response rate (ORR) in relapsed/refractory (R/R) Hodgkin lymphoma (HL) after autologous transplant (ASCT). The aim of this multicenter study, conducted in nine Hematology Departments of Rete Ematologica Pugliese, was to retrospectively evaluate the efficacy and safety of BV as salvage therapy and as bridge regimen to ASCT or allogeneic transplant (alloSCT) in R/R HL patients. Seventy patients received BV. Forty-five patients (64%) were treated with BV as bridge to transplant:16 (23%) patients as bridge to ASCT and 29 (41%) as bridge to alloSCT. Twenty-five patients (36%), not eligible for transplant, received BV as salvage treatment. The ORR was 59% (CR 26%). The ORR in transplant naïve patients was 75% (CR 31%). In patients treated with BV as bridge to alloSCT, the ORR was 62% (CR 24%). In a multivariate analysis, the ORR was lower in refractory patients (p?<?0.005). The 2y-OS was 70%. The median PFS was 17 months. Ten of the 16 (63%) naïve-transplant patients received ASCT, with 50% in CR before ASCT. In the 29 patients treated with BV as bridge to alloSCT, 28 (97%) proceeded to alloSCT with 25% in CR prior to alloSCT. The most common adverse events were peripheral neuropathy (50%), neutropenia (29%) and anemia (12%). These data suggest that BV is well tolerated and very effective in R/R HL, producing a substantial level of CR. BV may also be a key therapeutic agent to achieve good disease control before transplant, improving post- transplant outcomes, also in refractory and heavily pretreated patients, without significant overlapping toxicities with prior therapies.     

Expression and functional role of urokinase-type plasminogen activator receptor in normal and acute leukaemic cells

Urokinase-type plasminogen activator receptor (UPA-R-CD87) is a GPI-anchored membrane protein which promotes the generation of plasmin on the surface of many cell types, probably facilitating cellular extravasation and tissue invasion. A flow cytometric quantitative analysis of expression levels for UPA-R was performed on fresh blast cells from patients with acute myeloid leukaemia (AML, n = 74), acute lymphoblastic leukaemia (ALL, n = 24), and biphenotypic leukaemia (BAL, n = 3) using two CD87 monoclonal antibodies (McAbs) (3B10 and VIM5). Peripheral blood and bone marrow (BM) cells from 15 healthy adults served as controls. Using 3B10 McAb, UPA-R was expressed (>99%) by blood monocytes, neutrophils, and BM myelomonocytic precursors in controls, whereas resting T and B lymphocytes, and CD34⁺ cells were UPA-R negative. We also attempted to clarify whether UPA-R has a role in mediating neutrophil functions. Oriented locomotion induced by different chemotaxins and lysozyme release by granules stimulated with fMLP or PMA were significantly decreased when UPA-R was neutralized by CD87 McAb. In contrast, the anti-UPA-R McAb had no effect on superoxide anion generation of normal neutrophils. Blasts from AML showed a heterogenous pattern of expression for the UPA-R McAbs, with reactivity strictly dependent on FAB subtype. The highest UPA-R expression was seen in the M5 group: all patients tested (n = 20) showed strong positivity for the UPA-R McAb whereas only 12% (3/24) of ALL patients were CD87 positive, and 2/3 of BAL patients showed a dim expression for CD87. The number of receptors expressed by blast cells in 6/74 (8.1%) AML patients was higher than those of normal samples; in addition, since co-expression of UPA-R and CD34 was not found in normal haemopoietic cells, it may be postulated that CD87 can be used alone (when overexpressed) or in combination with CD34 for the detection of minimal residual disease. Results also indicated that patients with UPA-receptors >12 × 10³ ABC/cell, irrespective of FAB subtype, had a greater tendency for cutaneous and tissue infiltration and a higher frequency of chromosome abnormalities, thus suggesting the concept that cellular UPA-R content positively correlates with the invasive potential of AML cells. The combination of higher UPA-R positivity, abnormalities of chromosome 11, and M5 FAB morphology may identify a peculiar subset of AML, characterized by a more aggressive clinical course.     

Increased proliferation and apoptosis of colonic epithelial cells in dextran sulfate sodium-induced colitis in rats

We have evaluated morphologic alterations and epithelial cell apoptosis and proliferation of colonic mucosa in the acute and chronic phases of DSS-induced colitis. Colitis was induced in Sprague-Dawley rats by 7 days of 4% DSS oral administration followed by 7 days of tap water for one, two, and three cycles. Control rats receved tap water only. Morphological changes in colonic mucosa were evaluated and scored by light and scanning electron microscopy. Apoptosis was studied by TUNEL assay and cell proliferation by Ki-67 immunoreaction. The expression of both proapoptotic (Fas, FasL, Bax, p53) and antiapoptotic (Bcl2) cellular proteins was determined by immunohistochemistry. Morphologic assessment showed the most severe colonic epithelial lesions and inflammation in the distal colon with a trend to increasing severity from the first to the third DSS cycle. In DSS rats, the epithelial apoptotic index increased 20-fold after the first cycle and 120-fold after the second and third cycles compared with the controls; in the same way, the expression index of proapoptotic proteins (Fas, FasL, Bax, p53) dramatically increased. The proliferative index increased about 40 to 60-fold compared to controls, with no difference among the three DSS cycles. In conclusion, DSS-induced colitis in rats, which has many structural and ultrastructural features similar to those seen in human ulcerative colitis, is a suitable model for studying increased epithelial apoptosis and proliferation. Further studies employing this model will permitt two hypotheses to be tested. (1) Increased apoptosis may lead to a breakdown of the epithelial barrier function and facilitate the mucosal invasion of intraluminal microorganisms and/or antigens. (2) Abnormal and persistent epithelial hyperproliferation could be causally related to the development of colorectal cancers in the setting of chronic colonic inflammation.     

Exploration of the early insulin response by two small successive loads of I.V. glucose in normal and obese subjects

Summary Two 5 g glucose loads at 1-h interval were given to healthy controls and obese subjects with slightly altered or normal OGTT in order to explore the capacity of restoration of the ‘rapid insulin response’ to i.v. glucose. In the normal subjects, the two successive loads gave rise to identical responses as far as maximum increase (Δ_max), average increase at 2–5 min (Δ_{2–5 min}), area of increase 0–15 min (Δ_{0–15 min}) for both glucose and IRI, were concerned. Obese subjects could be divided on the basis of their insulin response to the first load into normal responders (group I) and high-responders (group II). In group I obese subjects, the responses to the second load were identical to those to the first. In group II obese subjects Δ_max, Δ_{2–5 min} and Δ_{0–15 min} of the insulin response to the second load were reduced as compared to the first.     

Removal of free light chains in hemodialysis patients without multiple myeloma: a crossover comparison of three different dialyzers

Background

Immunoglobulin light chains are classified as middle molecule uremic toxins able to interact with B lymphocyte membranes leading to the activation of transmembrane signaling. The ensuing impairment of neutrophil function can contribute to the chronic inflammation state of uremic patients, and the increased risk of bacterial infections or vascular calcifications. The aim of this crossover observational study was to assess the difference in free light chain removal by three different hemodialysis filters in patients not affected by multiple myeloma.

Methods

Free light chain removal was compared in the polymethylmethacrylate (PMMA) membrane Filtryzer BK-F, the polyphenylene HFR17 filter and the conventional polysulfone filter F7HPS. Twenty chronic hemodialysis patients were enrolled: mean age was 67.7?±?17.0 years, M/F?=?14/6, dialysis vintage (months) 25.5?±?32.0. The patients were randomized into two groups of treatment lasting 6 weeks each. The dialysis sessions checked were the midweek sessions and the blood was drawn at times 0, 120’ and 240’. Kappa (k) and lambda (λ) light chain levels, β2microglobulin (β2M), C reactive protein (CRP) and albumin were checked.

Results

K light chain levels were 345.0?±?100.0 mg/L, λ light chains were 121.4?±?27.0 mg/L. The values of k light chains at times 120’ and 240’ were significantly lower with PMMA and HFR17 than those obtained with F7. The reduction ratio per session (RRs) for k light chains was 44.1?±?4.3% with HFR17, 55.3?±?3.4% with PMMA, 25.7?±?8.3% with F7 (p?=?0.018). The RRs for λ light chains was 30.3?±?2.9% with HFR17, 37.8?±?17.3% with PMMA, 14.0?±?3.9% with F7 (p?=?0.032). As to β2M, RRs was 42.4?±?3.2% with HFR17 vs. 33.9?±?2.8% with PMMA vs. 6.3?±?1.9% with F7 (p?=?0.022). The three filters tested showed no differences in CRP or albumin levels.

Conclusion

In terms of light chain and β2M removal, the PMMA and on-line HFR filters are similar and both are significantly more effective than the F7 filter in chronic dialysis patients.

Trial registration

The present trial was registered retrospectively (NCT02950389, 31/10/2016).