Effectiveness of Liposomes Possessing Surface-Linked Recombinant B Subunit of Cholera Toxin as an Oral Antigen Delivery System

Liposomes appear to be a promising oral antigen delivery system for the development of vaccines against infectious diseases, although their uptake efficiency by Peyer’s patches in the gut and the subsequent induction of mucosal immunoglobulin A (IgA) responses remain a major concern. Aiming at targeted delivery of liposomal immunogens, we have previously reported the conjugation via a thioether bond of the G_M1 ganglioside-binding subunit of cholera toxin (CTB) to the liposomal outer surface. In the present study, we have investigated the effectiveness of liposomes containing the saliva-binding region (SBR) of Streptococcus mutans AgI/II adhesin and possessing surface-linked recombinant CTB (rCTB) in generating mucosal (salivary, vaginal, and intestinal) IgA as well as serum IgG responses to the parent molecule, AgI/II. Responses in mice given a single oral dose of the rCTB-conjugated liposomes were compared to those in mice given one of the following unconjugated liposome preparations: (i) empty liposomes, (ii) liposomes containing SBR, (iii) liposomes containing SBR and coadministered with rCTB, and (iv) liposomes containing SBR plus rCTB. Three weeks after the primary immunization, significantly higher levels of mucosal IgA and serum IgG antibodies to AgI/II were observed in the rCTB-conjugated group than in mice given the unconjugated liposome preparations, although the latter mice received a booster dose at week 9. The antibody responses in mice immunized with rCTB-conjugated liposomes persisted at high levels for at least 6 months, at which time (week 26) a recall immunization significantly augmented the responses. In general, mice given unconjugated liposome preparations required one or two booster immunizations to develop a substantial anti-AgI/II antibody response, which was more prominent in the group given coencapsulated SBR and rCTB. These data indicate that conjugation of rCTB to liposomes greatly enhances their effectiveness as an antigen delivery system. This oral immunization strategy should be applicable for the development of vaccines against oral, intestinal, or sexually transmitted diseases.     

Warm red blood cell autoantibodies and clinical diagnoses in patients with or without autoimmune hemolysis

ObjectivesRed blood cell autoantibodies (RBC autoAbs) of IgG class are found in the majority of patients with warm autoimmune hemolytic anemia (wAIHA) but sometimes also during the pretransfusion testing of patients with different diagnoses but without hemolysis. The aim of the study was to identify the main differences between these two groups of patients according to age, gender, subclass and titer of IgG RBC autoAbs and diagnosis.Material and methodsIn the 9-year retrospective study, data were collected from records of 291 patients with IgG RBC autoAbs detected by gel technique, from which 111 with wAIHA.ResultsMore than 85% of patients in both groups were over 40 years old, with male to female ratio 1:1.9 in wAIHA vs 1:1.3 in patients without hemolysis (P = 0.0916). The main characteristics of patients with wAIHA vs patients without hemolysis were: IgG only 38% vs 70%, IgG + Complement 62% vs 30%, total IgG1 79% vs 55%, IgG1 + IgG3 35% vs 11%, titer of 100 for IgG1 + IgG3 17% vs 3% (P < 0.0001), respectively, while titer of 100 for IgG1 18% vs 9% (P = 0.0241). The underlying diagnosis in wAIHA vs patients without hemolysis: hematologic disorders 41% vs 22% (P = 0.0006), autoimmune disorders 12% vs 13% (P = 0.8033), solid tumors 5% vs 14% (P = 0.0154) and surgery procedures 6% vs 26% (P < 0.0001).ConclusionWe observed more wAIHA patients with high titer of IgG1 and high prevalence of IgG1 + IgG3 and consider that patients without hemolysis having identical results might be interesting to find out how they are protected from damage by RBC autoAbs.     

IgE anti-respiratory syncytial virus antibodies detected in serum of pediatric patients with asthma

Respiratory syncytial virus (RSV) causes lower respiratory tract disease in infants and young children, and is a public health concern, as is the increase in pediatric asthma. Respiratory viral infections may trigger asthma exacerbations. However, it remains unknown whether RSV infection may have a specific association with asthma. Total serum IgE, and IgE- and IgG-anti-RSV Ab responses were studied in older asthmatic compared with non-asthmatic children (M/F, mean age: 14) (N = 30, N = 43, respectively). We found: (1) total serum IgE was higher in asthmatic compared with non-asthmatics (P < 0.001); (2) total serum IgE did correlate with IgE anti-RSV Abs (P < 0.001), and with IgG anti-RSV Abs (P = 0.008) in all subjects; (3) total serum IgE levels did correlate with IgE anti-RSV in asthmatics (P = 0.047), but not in non-asthmatics (P = 0.13); (4) IgE anti-RSV Abs did correlate with IgG anti-RSV Abs in all subjects (P = 0.001); (5) IgE- and IgG-anti RSV Abs were higher in asthma compared with no asthma (P = 0.003; <0.001, respectively); (6) there was a significant association between age and IgE anti-RSV in non-asthma (P = 0.008), but not in asthma (P = 0.64). Our findings indicate that IgE-anti-RSV Ab responses may play important roles in RSV infection and asthma.     

Utility of serum IgG,IgG4 and carbonic anhydrase II antibodies in distinguishing autoimmune pancreatitis from pancreatic cancer and chronic pancreatitis

PurposeAutoimmune pancreatitis (AIP) can mimic pancreatic cancer in its clinical presentation, imaging features and laboratory parameters. The aim of our study was to compare IgG, IgG4 and anti-CAIIAb serum levels in patients with AIP, pancreatic adenocarcinoma (PA) and chronic pancreatitis (CP) and to assess their clinical significance and utility in differential diagnosis of pancreatic diseases.Patient/methodsThe study included 124 patients: 45 with PA, 24 with AIP and 55 with CP. Peripheral venous blood samples were obtained from all analyzed patients at the time of hospital admission and total IgG, IgG4 and anti-CAIIAB serum levels were measured using ELISA tests.ResultsSerum levels of IgG, IgG4 and anti-CAIIAb were significantly higher in patients with AIP compared to PA and CP patients (p < 0.001). In AIP patients the median IgG levels were 19.7 g/l, IgG4 levels – 301.9 mg/dl and anti-CAIIAb – 81.82 ng/ml, compared to 10.61 g/l, 123.2 mg/dl and 28.6 ng/ml, respectively, in PA patients. IgG4 for the cut-off 210 mg/dl showed the best sensitivity and specificity (83.8% and 89.5%) in AIP diagnosis compared to IgG (69.3% and 87.3%, respectively) and anti-CAIIAb (45.3% and 74.3%). However, 16 (35.5%) patients with PA and 14 (25.4%) patients with CP had IgG4 levels greater than 140 mg/dl. Moreover, in 3 (6.67%) patients with pancreatic cancer those values were greater than 280 mg/dl. No patients with CP had IgG4 more than 280 mg/dl.ConclusionsIgG4 at cut-off 210 mg/dl showed the best sensitivity and specificity in AIP diagnosis compared to IgG and anti-CAIIAb, however elevations of serum IgG4 may be seen in subjects without AIP, including pancreatic cancer.     

Anti-Tax antibody levels in asymptomatic carriers,oligosymptomatic carriers,patients with rheumatologic disease or with HAM/TSP do not correlate with HTLV-1 proviral load

BackgroundHTLV-1 infects millions of people around the world and induces myelopathy (HAM/TSP), adult T-cell leukemia (ATL) or other inflammatory or rheumatologic diseases. The host–virus interaction causes asymptomatic carriers to develop HAM/TSP. Biomarkers are needed to predict patients who are at risk for HAM/TSP. Tax is highly immunogenic and is a major target protein recognized by cytotoxic T lymphocytes. Anti-Tax antibodies are involved in HAM/TSP pathogenesis.ObjectivesTo assess anti-Tax IgG reactivity with a flow cytometry assay (FCA) using an infection/transfection system with Vaccinia virus and pLW44/Tax-expressing Tax and to correlate the anti-Tax response and the HTLV-1 proviral load.Study design: We enrolled 81 individuals: 9 HTLV-1 seronegative (NP) and 72 HTLV-1 positive (23 HTLV-1 asymptomatic carriers (AC), 12 oligosymptomatic patients (OL), 7 with rheumatologic diseases (DR) and 30 with HAM/TSP (HT)). Anti-Tax reactivity was assessed by FCA, and HTLV-1 proviral load was measured with real time PCR.ResultsThe HT and DR groups showed greater anti-Tax IgG reactivity (p < 0.001 and p < 0.05 comparing HT to the OL and AC group, respectively; p < 0.05 comparing DR to the OL group), and the reactivity in the DR + HT group was significantly different when compared to the AC group (p < 0.05) and to the OL group (p < 0.001). The proviral load was higher in the HT group compared to the OL (p < 0.001) and in the HT + DR group compared to OL (p < 0.001). There was no correlation between anti-Tax IgG reactivity and proviral load in any of the HTLV-1-infected groups.ConclusionThese findings suggest that although anti-Tax IgG reactivity and the HTLV-1 proviral load are important markers of the development of HTLV-1-associated diseases, their levels are not correlated.     

Clinical implications of hepatitis B surface antigen quantitation in the natural history of chronic hepatitis B virus infection

BackgroundHBsAg quantitation may be useful for managing patients with hepatitis B virus (HBV) infection.ObjectivesWe explored the clinical implications of HBsAg quantitation for patients with HBsAg levels >250 IU/ml (Abbott Diagnostics).Study designTwo hundred and thirty-three HBV-infected patients comprising 29 immune tolerance cases, 49 treatment-naïve HBeAg-positive chronic hepatitis B (CHB) cases, 91 inactive HBV carrier cases, and 64 treatment-naïve HBeAg-negative CHB cases were analyzed. HBsAg was quantified by the Architect HBsAg assay (Abbott Diagnostics) after a 1:500 automated dilution.Results and conclusionsHBsAg (log 10 IU/ml) was established for immune tolerance (4.50 ± 0.43), HBeAg-positive CHB (4.17 ± 0.66), inactive HBV carrier (3.32 ± 0.44), and HBeAg-negative CHB (3.23 ± 0.40); (p = 4.92 × 10⁻³⁵). No significant difference was observed between inactive HBV carrier and HBeAg-negative CHB (p = 0.247). The proportions of HBsAg <2000 IU/ml for inactive HBV carrier and HBeAg-negative CHB were 51.6% and 59.3%, respectively (p = 0.341). Positive correlations between HBsAg and HBV DNA were observed for immune tolerance (p = 1.23 × 10⁻⁴) and HBeAg-positive CHB (p = 0.003), but not for HBeAg-negative CHB (p = 0.432). A negative correlation between HBsAg and age was observed for immune tolerance (p = 0.030), HBeAg-positive CHB (p = 0.016), and inactive HBV carrier (p = 0.001), but not in HBeAg-negative CHB (p = 0.249). No significant differences between HBsAg and ALT for HBeAg-positive (p = 0.338) or HBeAg-negative CHB (p = 0.564) were observed. For patients with HBsAg quantitation >250 IU/ml, HBsAg may reflect HBV DNA replication for HBeAg-positive cases. HBsAg is not a suitable marker for evaluating hepatitis activity and distinguishing between cases of HBeAg-negative CHB and inactive HBV carrier state.     

Macrophage migration inhibitory factor contributes to anti-neutrophil cytoplasmic antibody-induced neutrophils activation

BackgroundMacrophage migration inhibitory factor (MIF) is an inflammatory mediator released by macrophages that is central to the innate immune system, with an upstream role in the inflammatory cascade. MIF is one of the most important pathogenic factors in the development of the autoimmune diseases. In the current study, we investigated the role of MIF in anti-neutrophil cytoplasmic antibody (ANCA)-induced neutrophil activation.MethodsPlasma levels of MIF from 31 patients with active ANCA-associated vasculitis (AAV) were analyzed by ELISA. The various effects of MIF in ANCA-induced neutrophil respiratory burst and degranulation were measured.ResultsPlasma levels of circulating MIF were significantly higher in AAV patients with active disease compared with those in remission and healthy controls. Compared with MIF-primed neutrophils, the MFI value increased significantly in MIF-primed neutrophils further activated with MPO-ANCA-positive IgG or PR3-ANCA-positive IgG (270.8 ± 9.7 vs. 421.5 ± 9.7, P < 0.001; 270.8 ± 9.7 vs. 414.1 ± 15.6, P < 0.001, respectively). Compared with MIF-primed neutrophils, the lactoferrin concentration increased significantly in the supernatant of MIF-primed neutrophils further activated by MPO-ANCA-positive IgG (567.8 ± 61.2 ng/ml vs. 1677.0 ± 42.5 ng/ml, P < 0.001) or PR3-ANCA-positive IgG (567.8 ± 61.2 ng/ml vs. 1546.0 ± 116.2 ng/ml, P < 0.001), respectively. Interleukin-8 (IL-8), IL-6 and IL-23 were involved in ANCA-induced activation of MIF-primed neutrophils.ConclusionsMIF primes neutrophils by increasing ANCA antigen translocation. The primed neutrophils can be further induced by ANCA, resulting in respiratory burst and degranulation.     

Caspase-cleaved fragments of cytokeratin-18 as a marker of inflammatory activity in chronic hepatitis B virus infection

BackgroundThe differential diagnosis between inactive carrier and active hepatitis is important in patients with chronic hepatitis B (CHB) virus infection. Serum cytokeratin (CK)-18 fragments (M30-antigen) are proposed as biomarkers of apoptosis.ObjectivesWe investigated whether serum M30-antigen levels might help to characterize the various phases of CHB and predict the state of significant inflammation in patients with CHB.Study designA total of 339 CHB patients who underwent liver biopsy, were included. Serum M30-antigen levels were compared between inactive carriers (n = 21), patients with HBeAg-negative hepatitis (n = 95), HBeAg-positive hepatitis (n = 141) and liver cirrhosis (n = 82).ResultsSerum M30-antigen levels were correlated significantly not only with AST (r = 0.544, p < 0.001) and ALT (r = 0.315, p < 0.001) and but also inflammatory grading score on liver biopsy (r = 0.240, p < 0.001). Serum M30-antigen level in HBeAg-negative CHB was significantly higher than that of inactive HBV carrier (399.78 U/L vs 148.90 U/L, p < 0.001). Multivariate analysis showed that AST (p < 0.001), albumin (p = 0.009) and M30-antigen (p = 0.020) were the independent predictors of significant inflammation. Combined serum M30-antigen level (>344 U/L) and AST (>78 IU/L) measurement provided the most accurate identification of significant inflammation, showing 38.2% sensitivity, 96.1% specificity, 91.0% positive predictive value and 56.1% negative predictive value.ConclusionsSerum M30-antigen can be a predictive marker for distinguishing between inactive carrier and HBeAg-negative CHB. Serum M30 levels are associated with the presence of significant inflammation, especially in patients with normal or minimally elevated ALT in CHB patients.     

Polymyositis/dermatomyositis and nasopharyngeal carcinoma: The Epstein–Barr virus connection?

BackgroundPolymyositis (PM) and dermatomyositis (DM) are associated with high risk of nasopharyngeal carcinoma (NPC) in Asian countries. Epstein–Barr virus (EBV) might induce autoimmunity and malignancies in susceptible individuals.ObjectivesTo investigate the association of EBV with PM/DM and NPC in PM/DM patients.Study designSerum levels of anti-EBV viral capsid antigens (VCA) and anti-EBV-coded nuclear antigens-1 (EBNA-1) antibodies were measured by ELISA, and EBV DNA loads were determined using real-time PCR for 98 PM/DM patients, 94 systemic lupus erythematosus (SLE) patients and 370 healthy controls (HC). Anti-transfer-RNA synthetase antibodies (ASA) were determined by radioimmunoprecipitation for PM/DM patients.ResultsThirteen (13.3%) of PM/DM patients vs. none of SLE patients had detectable NPC. ASA were detectable in 31.7% of PM/DM without malignancy, while lack of ASA in any PM/DM patient with NPC. IgA anti-EBNA-1 were detectable in 30.6% of PM/DM patients and 31.9% of SLE patients, but only in 4.1% of HC (odds ratio [OR] 10.44 and 11.12 respectively, both p < 0.001). Significantly higher positivity for IgA anti-EBNA-1 were observed in PM/DM with NPC than in those without malignancy (OR 44.7, p < 0.01). Significantly higher positivity for EBV genome were observed in PM/DM with NPC than in those without malignancy (OR 43.9, p < 0.01), in SLE patients (OR 13.2, p < 0.05) and in HC (OR 99.4, p < 0.001). EBV DNA loads were significantly higher in PM/DM with NPC compared with those without malignancy and HC.ConclusionsOur results showed a positive association of EBV with PM/DM and NPC. PM/DM patients who have IgA anti-EBNA-1 or increased EBV DNA loads should be highly suspected to have occult NPC.     

Viral excretion and antibody titers in children infected with hepatitis A virus from an orphanage in western India

BackgroundHepatitis A is endemic in India and mainly causes sporadic infections. However, children in childcare centers, schools and orphanages are vulnerable to common-source outbreaks as they have naive hosts.ObjectivesTo investigate hepatitis A outbreak in an orphanage from Pune, India.Study DesignMonitoring of virus excretion and anti-HAV antibody levels in hepatitis A virus (HAV) infected children.ResultsThe orphanage housed 93 children of the age 1 month-6.5 years. Analysis of the collected serum (n = 78) and stool samples (n = 63) revealed 20 children to be either positive for anti-HAV IgM antibodies or excreting HAV, 14 being symptomatic and 6 asymptomatic, while 32 were already anti-HAV IgG positive either due to past HAV exposure (n = 7, mean log antibody titers: 2.96) or maternal antibodies (n = 25, mean log antibody titers: 1.13). Serum samples, taken 4 weeks apart, did not show any significant difference in the IgM and IgG antibody levels either. However, virus excretion decreased significantly after 15 days in symptomatic children (mean log HAV RNA copies/ml 1.03 + 0.30), while asymptomatic children continued to excrete higher viral loads, at constant levels (mean log HAV RNA copies/ml 2.33 + 0.33), for up to 90 days.ConclusionsThough virus excretion continued up to 90 days in all HAV infected children, asymptomatic children excreted higher viral loads for longer period and hence can contribute significantly in person-to-person virus transmission. All children should be vaccinated in such set ups.     

Rapid deposition of glomerular IgA in BALB/c mice by nivalenol and its modifying effect on high IgA strain (HIGA) mice

To clarify the underlying mechanisms of IgA nephropathy (IgAN) induced by nivalenol (NIV), a trichothecene mycotoxin, we examined the time and dose relationships of glomerular deposition of IgA by NIV in BALB/c mice (Experiment 1), and also evaluated the modification of NIV on spontaneous IgAN in an inbred murine model, a high IgA strain (HIGA), during its early stage of pathogenesis (Experiment 2). In Experiment 1, female BALB/c mice were given a diet containing 0, 12, or 24 ppm concentration of NIV for 4 or 8 weeks. An increase in serum IgA levels was found at 24 ppm from 4 weeks. At week 8 of treatment, dose-dependent increases in serum IgA levels and glomerular deposition of IgA and IgG were observed without accompanying histopathological glomerular changes. On the other hand, in Experiment 2, control HIGA mice exhibited rather high levels of serum IgA as compared with BALB/c mice from 4 weeks of experiment as well as glomerular deposition of IgA and IgG and mesangial proliferation as revealed at week 8. NIV at 24 ppm further increased serum IgA in this strain; however, it did not enhance glomerular immunoglobulin deposition or histopathological lesion. These results suggest that NIV-induced increase of serum IgA levels may be primarily responsible for glomerular immunoglobulin deposition; however, NIV does not enhance glomerular IgA deposition that may lead to exacerbation of predisposed IgAN in the short term, irrespective of the further elevation of serum IgA from the high basal levels.     

Sialylation of antibodies in kidney recipients with de novo donor specific antibody,with or without antibody mediated rejection

BackgroundDSA are associated with reduced long-term transplant function and increased prevalence of chronic rejection in some patients, whereas others do not: our goal was to determine whether the sialylation of IgG and DSA could help to explain in these last cases their “non-aggressive” and/or “protective” biological activity.MethodsThe sialylation level of total IgG in blood from two groups of kidney-transplant patients with de novo DSA, one with an AMR (DSA⁺AMR⁺), and the other without were studied.ResultsIn the DSA⁺AMR⁻ patients total IgG were more sialylated at time of transplant, and at the first detection of DSA, class I DSA were 2.6-fold more sialylated (mean 9.943 ± 1.801 versus 3.898 ± 2.475, p = 0.058); DSA⁺AMR⁺ patients exhibited higher levels of class II DSA.ConclusionsIn our study, higher levels of sialylated IgG are detectable on day of transplant in patients who do not develop AMR, they have higher sialylated class I DSA at the initial detection of DSA, whereas class II DSA are significantly higher in patients who develop AMR. This is the first report suggesting that transplant outcome, and particularly AMR, is associated with levels of sialylated IgG antibodies. Our data suggest that DSA are functionally heterogeneous and that further studies with an enlarged cohort may improve our understanding of their clinical impact.     

Mumps outbreaks in a highly vaccinated population: Investigation of a neutralization titre against the current circulating wildtype genotype G5 mumps virus

BackgroundMumps outbreaks continue to occur globally, despite high levels of uptake of the mumps vaccine.ObjectivesIn order to address immunity to the current circulating wildtype virus, we sought to determine a mumps G5 specific IgG quantitative value which correlates with genotype G5 specific neutralization ability in vitro.Study designSera from 199 individuals including controls and acute mumps cases were assessed for mumps specific IgG titres using five different enzyme immunoassays coated with antigen from different mumps virus strains. A subset of 66 sera was also assessed for in vitro neutralizing antibody against a contemporary circulating genotype G5 mumps virus.ResultsFor all the different antigenic targets, mumps specific IgG titres were higher in patients following acute mumps infection compared to controls. In acute mumps infected patients, females showed significantly higher serum titres of anti-G5 IgG compared to males (p < 0.05). Furthermore, control males did not show any change in G5 specific IgG with increasing age whereas females show a progressive rise in titre. Linear regression analysis revealed a significant association between the mumps G5 specific IgG levels in the EIA and the in vitro neutralization titres (r² = 0.59).ConclusionsSpecific IgG to the current circulating genotype G5 mumps strain showed significantly lower titres in males which supports our previous observation that there is a male gender bias in cases of acute mumps infection. Furthermore, in this preliminary study, the data indicate that genotype G5 specific IgG levels of >40 RU/ml are required for neutralization capability to be observed in vitro.     

Clinical activity of pemphigus vulgaris relates to IgE autoantibodies against desmoglein 3

Pemphigus vulgaris (PV) is a severe autoimmune bullous skin disease and is primarily associated with IgG against desmoglein 3 (dsg3), a desmosomal adhesion protein. In light of the recent association of autoreactive T helper (Th) 2 cells with active PV, the present study sought to relate the occurrence of Th2-regulated dsg3-specific autoantibody subtypes, i.e. IgE and IgG4, in 93 well-characterized PV patients. Patients with acute onset PV (n = 37) showed the highest concentrations of serum IgE and IgG4 autoantibodies, which were significantly lower in PV patients in remission (n = 14). Furthermore, there was a strong correlation between dsg3-reactive IgE and IgG4 in acute onset, but not in chronic active (n = 42) or remittent patients. Additionally, intercellular IgE deposits were detected in the epidermis of acute onset PV. Thus, dsg3-specific IgE and IgG4 autoantibodies are related to acute onset disease which provides additional support to the concept that PV is a Th2-driven autoimmune disorder.     

Glycyrrhetinic acid-modified poly(ethylene glycol)–b-poly(γ-benzyl l-glutamate) micelles for liver targeting therapy

Liver targeted micelles were successfully constructed via self-assembly of glycyrrhetinic acid (GA)-modified poly(ethylene glycol)–b-poly(γ-benzyl l-glutamate) (GA–PEG–PBLG) block co-polymers, which were fabricated via ring opening polymerization of γ-benzyl l-glutamate N-carboxyanhydride monomer initiated by GA-modified PEG. The in vivo biodistribution and the in vitro cellular uptake of these micelles were investigated. The results showed that the relative uptake of doxorubicin (DOX)-loaded micelles (DOX/GA–PEG–PBLG) in liver was much higher than in other tissues, and the resulting DOX concentration in liver was about 2.2-fold higher than that from the micelles without modification by GA. Moreover, the cellular uptake study demonstrated that the introduction of GA to the micelles could significantly increase the affinity for human hepatic carcinoma 7703 cells, which induced a 3.7-fold higher endocytosis than unmodified ones. The cytotoxicity of DOX/GA–PEG–PBLG micelles (IC₅₀ 47 ng ml^?1) was much higher than that of free DOX (IC₅₀ 90 ng ml^?1). These results indicate that GA-modified micelles have great potential in liver targeting therapy.     

Polypeptide-based combination of paclitaxel and cisplatin for enhanced chemotherapy efficacy and reduced side-effects

A novel methoxy poly(ethylene glycol)-b-poly(l-glutamic acid)-b-poly(l-phenylalanine) (mPEG-b-P(Glu)-b-P(Phe)) triblock copolymer was prepared and explored as a micelle carrier for the co-delivery of paclitaxel (PTX) and cisplatin (cis-diamminedichlo-platinum, CDDP). PTX and CDDP were loaded inside the hydrophobic P(Phe) inner core and chelated to the middle P(Glu) shell, respectively, while mPEG provided the outer corona for prolonged circulation. An in vitro release profile of the PTX + CDDP-loaded micelles showed that the CDDP chelation cross-link prevented an initial burst release of PTX. The PTX + CDDP-loaded micelles exhibited a high synergism effect in the inhibition of A549 human lung cancer cell line proliferation over 72 h incubation. For the in vivo treatment of xenograft human lung tumor, the PTX + CDDP-loaded micelles displayed an obvious tumor inhibiting effect with a 83.1% tumor suppression rate (TSR%), which was significantly higher than that of a free drug combination or micelles with a single drug. In addition, more importantly, the enhanced anti-tumor efficacy of the PTX + CDDP-loaded micelles came with reduced side-effects. No obvious body weight loss occurred during the treatment of A549 tumor-bearing mice with the PTX + CDDP-loaded micelles. Thus, the polypeptide-based combination of PTX and CDDP may provide useful guidance for effective and safe cancer chemotherapy.     

Evaluation of antibiotic releasing porous polymethylmethacrylate space maintainers in an infected composite tissue defect model

This study evaluated the in vitro and in vivo performance of antibiotic-releasing porous polymethylmethacrylate (PMMA)-based space maintainers comprising a gelatin hydrogel porogen and a poly(dl-lactic-co-glycolic acid) (PLGA) particulate carrier for antibiotic delivery. Colistin was released in vitro from either gelatin or PLGA microparticle loaded PMMA constructs, with gelatin-loaded constructs releasing colistin over approximately 7 days and PLGA microparticle-loaded constructs releasing colistin for up to 8 weeks. Three formulations with either burst release or extended release at different doses were tested in a rabbit mandibular defect inoculated with Acinetobacter baumannii (2 × 10⁷ colony forming units ml^?1). In addition, one material control that released antibiotic but was not inoculated with A. baumannii was tested. A. baumannii was not detectable in any animal after 12 weeks on culture of the defect, saliva, or blood. Defects with high dose extended release implants had greater soft tissue healing compared with defects with burst release implants, with 8 of 10 animals showing healed mucosae compared with 2 of 10 respectively. Extended release of locally delivered colistin via a PLGA microparticle carrier improved soft tissue healing compared with implants with burst release of colistin from a gelatin carrier.     

The impact of Helicobacter pylori on EGF,EGF receptor,and the c-erb-B2 expression

PurposeIncreased expression of epidermal growth factor (EGF), its receptor (EGFR), and c-erb-B2 protein, which is homological with the EGF receptor, in gastric mucosa, may play a role in gastric carcinogenesis. We assessed if the infection and eradication of Helicobacter pylori (H. pylori) affects the gastric expression of growth factors and serum gastrin concentrations.Patients/methodsWe examined immunohistochemically gastric EGF and both receptors’ expression in: gastric cancer (GC; n = 29), chronic gastritis with H. pylori infection (GHp+; n = 40) before and after eradication and in patients without H. pylori infection (GHp−; n = 42).ResultsBefore the eradication therapy, gastric mucosal EGF and both receptor's expressions in GHp+ patients were increased compared to GHp− (p < 0.05), but were similar to GC. After eradication, EGF and the receptor's expression significantly decreased in the gastric body. Both EGFR and c-erb-B2 expression in the antrum were still higher than in GHp− (p < 0.05), and remained comparable to GC.ConclusionsIn patients with H. pylori infection the gastric mucosal EGF, EGFR, and c-erb-B2 expressions are similar to those observed in gastric cancer. The persistence of the antral expression of receptors after eradication, at a level comparable to the gastric cancer group, suggests their eventual role in the progression of changes initiated by H. pylori toward carcinogenesis.