Journal of immunoassay & immunochemistry最新文献

Background: Pneumococcal diseases pose a significant public health concern globally, particularly among young children and the elderly. Vaccination plays a crucial role in their prevention. This study evaluated the functional immune responses to Pneumococcal polysaccharide vaccine serotypes in healthy Indian adults before and after administering a single dose of PPSV23 immunization.

Methods: A total of 125 healthy participants aged 18-65 received the PPSV23 vaccine, and their pre- and post-immunization sera were analyzed by MOPA. Opsonic Index, Geometric mean OPA titers and fold increase for each serotype was calculated.

Results: The highest baseline OPA GMTs were observed for serotypes 33F,17F,9N,20, and 6B. The lowest OPA GMTs were noted against types 1 and 12F. OPA GMTs post-vaccination increased significantly for all serotypes, with geometric mean fold rise (GMFR) ranging from 4.3 to 267.5. Participants with low pre-immunization OPA titers (<8 & <64) showed significant increases in OI fold raise across all tested serotypes post-vaccination. This robust immune response was consistent across serotypes, indicating highly effective seroconversion in individuals with low baseline antibody levels.

Conclusion: The PPSV23 vaccine elicits a strong immunogenic response in individuals with low pre-immunization OPA titers, achieving substantial increases in opsonic index fold raise across various serotypes.

Rotavirus diarrhea and Ascaris lumbricoides (Al) infection increase intestinal morbidity and were associated with altered immune responses that compromise the vaccine efficacy in children. The serum level of rotavirus specific IgA (RV-IgA) and cytokine profiles in A. lumbricoides (AI) infected preschool-aged Nigerian children were estimated following oral rotavirus vaccination. Nineteen of the 149 preschool-aged children (aged 6 to 60 months) with Ascaris lumbricoides infection paired with age and sex-matched helminth - free children were administered with oral rotavirus vaccine after intestinal helminth screening using stool sample concentration technique. Separated sera from 3 mL venous blood samples were collected and estimated for cytokines (IFN-γ, TNF-α, IL-4, IL-8 IL-6, IL-10) and RV-IgA before and three weeks after rotavirus vaccination using Enzyme Linked Immunosorbent Assay. IFN-γ, IL-8, IL-4 were significantly lower at post-vaccination in Al-infected children compared with pre-vaccination. Serum IL-10 was significantly higher at post-vaccination in both Al-infected children and helminth-free controls, compared with pre-vaccination levels (p < 0.05). Pre-vaccination IL-8 and IL-6 were significantly higher in Ascaris lumbricoides-infected children, while the post-vaccination IL-8 was significantly higher in Ascaris lumbricoides-infected compared with control. At post-vaccination period, RV-IgA level was lower in Al-infected children and significantly higher in helminth - free control group compared to pre-vaccination RV-IgA level. Ascaris lumbricoides infection contributed to down-regulation of some cytokines and antibody responses to oral rotavirus vaccine.

Our study evaluated the possible interference of Burosumab (human recombinant monoclonal antibody directed against N-terminal domain of FGF23) on the immunoassay of intact FGF23 (iFGF23) with the Liaison XL. The analytical method uses three different antibodies, one of which directed against the N-terminal portion of FGF23. The evaluation of the method accuracy involved the fully automated execution of a dilution test on EDTA plasma from 5 subjects who had not received any monoclonal antibody (mAb), 20 EDTA plasma from patients treated with Burosumab, and 2 EDTA plasma from subjects who had not received any mAb in witch an adequate volume of Burosumab had been added in vitro. One sample with specific diluent (LIAISON® FGF 23) with an adequate volume of Burosumab had been added in vitro. The dilution assay provided highly inaccurate iFGF23 results in samples with therapeutic concentrations of Burosumab and in samples with concentrations below the LoQ (6.5 pg/mL). The addition of Burosumab to the diluent did not produce any analytical interference. Dissociation of iFGF23 from the mAb-target complex in diluted sample could explain the loss of accuracy in the iFGF23 immunoassay using the Liaison XL analyzer. Burosumab could be an interferent in immunoassay procedures of iFGF23.

Conventional oral vaccine delivery in poultry is challenging due to vaccine degradation in the gastrointestinal (GI) environment and the need for cold-chain storage. Microencapsulation offers a solution by protecting vaccines from GI degradation and improving stability. Natural polymers like alginate and cashew gum have mucoadhesive properties, making them promising candidates for oral vaccine delivery. This study developed cashew-alginate microbeads and a powdered dose form for oral vaccine delivery in chickens. The microbeads were created using ionotropic gelation, while the powdered form was obtained via freeze-drying. These formulations were characterized for size, shape, and stability using scanning electron microscopy (SEM), light microscopy, X-ray diffraction (XRD), and Energy Dispersive X-ray (EDX). Peak adhesion time (PAT) was determined using chicken intestinal and esophageal tissues, and antigenicity was assessed with in-vitro hemagglutination (HA) and hemagglutination inhibition (HI) assays. The microbeads exhibited a spherical shape with a porous structure, suggesting enhanced antigen accommodation. Hemagglutination Inhibition tests indicated that the experimental vaccine remained effective without cold-chain storage for three months. These findings suggest that cashew-alginate microbeads are promising for oral vaccine delivery in poultry.

Background: Although numerous mechanisms are involved in vitiligo pathogenesis, few studies correlate N-acetyltransferase 2 to this disease.

Aim: To assess the N-acetyltransferase 2 (rs1799929) gene and its serum levels in vitiligo patients.

Subjects and methods: In this case-control study, 65 vitiligo cases were compared to 65 age- and sex-matched healthy controls. Serum NAT2 levels and the NAT2 gene polymorphism (rs1799929) were evaluated using ELISA and real-time PCR, respectively.

Results: Serum N-acetyltransferase 2 levels were significantly lower in cases than in controls, 1.24 ± 0.31 vs. 2.01 ± 0.46 (p = 0.001). CC genotype was more dominant in controls (58.5%) than in cases (20%). TT and CT genotypes were more dominant in cases (30.8% and 49.2%) than in controls (13.8% and 27.7%), respectively (p = 0.001). The C allele was more prominent in controls (72.3%) than in cases (44.6%) while the T allele was more dominant in cases (55.4%) than in controls (27.7%) (p = 0.001). N-acetyltransferase 2 slow acetylator phenotype (TT genotype) was higher in cases (30.8%) than in controls (13.8%) and rapid acetylator phenotypes (CC and CT genotypes) were higher in controls (86.2%) than in cases (69.2%) (p = 0.035).

Conclusion: Slow acetylator genotype (TT) of NAT2 gene (rs1799929) and low serum levels of NAT2 enzyme might play a role in the susceptibility and pathogenesis of vitiligo.

Althoughchronic hepatitis C (CHC) therapies based on direct-acting antiviral (DAA) agents safely improved treatment effectiveness, some cases do not obtain sustained virological response (SVR) and, thus, evaluating factors that may be related to treatment failure is very important. We aimed to evaluate the association of baseline serum collagen IV with DAA treatment failure in Egyptian patients with CHC. A total of 175 CHC patients (100 responders and 75non-responders tosofosbuvir/daclatasvir) were included. Collagen IV was assessed using sensitive chemiluminescent immunoassay. There was distinctly higher (P < 0.0001) collagen IV in non-responders compared to responder patients as the median (interquartile range) were 19.02 (13.4-25.2) vs.9.7 (7.2-12.3) µg/L, respectively. Collagen IV has a good ability for distinguishing nonresponders from responder patients (AUC = 0.890) with sensitivity of 92%, specificity 72%, PPV 71.1%, NPV 92.3% and accuracy of 80.6%. Collagen IV was correlated (p < 0.05) with decreased albumin (r=-0.266), elevated APRI (r = 0.288), and elevated FIB-4 (r = 0.281) scores. In conclusion,these findings suggested the remarkable role of baseline collagen IV in the prediction of HCV DAAs treatment response. Thus, however further studies are needed, its measurement may improve treatment duration and the disease control.

SARS-CoV-2, identified in Wuhan, China, in December 2019, is the third coronavirus responsible for a global epidemic, following SARS-CoV (2002) and MERS-CoV (2012). Given the recent emergence of COVID-19, comprehensive immunological data are still limited. The susceptibility and severity of SARS-CoV-2 infection are influenced by various host factors, including hormonal changes, genetic variations, inflammatory biomarkers, and behavioral attitudes. Identifying genetic factors contributing to infection severity may accelerate therapeutic development, including drug repurposing, natural extracts, and post-vaccine interventions (Initiative and Covid, 2021). This review discusses the human protein machinery involved in (a) SARS-CoV-2 host receptors, (b) the human immune response, and (c) the impact of demographic and genetic differences on individual risk for COVID-19. This review aims to clarify host factors implicated in SARS-CoV-2 susceptibility and progression, highlighting potential therapeutic targets and supportive treatment strategies.

Background: Nigeria remains one of the countries with a high hepatitis B virus (HBV) burden in Africa. Reports have indicated the presence of mixed HBV genotypes in Nigeria; however, there is still paucity of data regarding mixed genotype infections particularly in the Southern part of the country.

Objective: Our aim is to determine the HBV genotype distribution among HBsAg-positive gastroenterology patients at the University College Hospital Ibadan, Nigeria.

Method: Serum samples were screened for HBsAg by ELISA, and positive samples were genotyped by semi-nested multiplex PCR for HBV genotypes A, B, C, D, E and F.

Results: Data generated were analyzed in R-studio. A total of 81/90 (90%) of HBsAg-positive samples were successfully genotyped, and genotype A was most prevalent with 15.7%, while genotypes B and E were the least with 1.2% each. Genotypes A/C infection was the highest among mixed infections with 40% prevalence, while genotypes A/D were the least prevalent mixed infection with 4.8%.

Conclusion: We advocate for a comprehensive genotype analysis in larger cohorts across Nigeria, to give a more comprehensive understanding of the distribution and prevalence of different HBV genotypes population wide.

Vitiligo is a common skin disorder where melanocytes, the cells that produce skin pigment, are destroyed by the immune system, leading to white patches on the skin and mucous membranes. This condition affects 0.4% to 2.0% of the global population, with a higher prevalence in females and often beginning in childhood. In India, about 1% of the population is affected, particularly in northern regions, with a higher incidence in females and links to other autoimmune diseases. This review examines recent progress in understanding vitiligo and its treatment. It focuses on the genetic, autoimmune, and environmental factors involved in the disease and highlights new therapies, such as targeted molecular treatments and advanced repigmentation methods. Current research shows that oxidative stress and genetic predispositions contribute to the autoimmune destruction of melanocytes. Novel drug delivery systems, including liposomes, nanoemulsions, and nanostructured lipid carriers, have improved treatment effectiveness. Clinical trials are exploring new treatments like Ruxolitinib cream and melanocyte transplantation, while teledermatology is becoming useful for managing patients. Vitiligo also poses a significant economic burden due to its impact on patients' quality of life. Continued research is essential to develop better, more accessible treatments and reduce the economic impact of vitiligo.