A comparative study on the physicochemical and biological stability of IgG1 and monoclonal antibodies during spray drying process

Background: The main concern in formulation of antibodies is the intrinsic instability of these labile compounds. To evaluate the physicochemical stability of antibody in dry powder formulations, physical stability of IgG1 and a monoclonal antibody (trastuzumab) during the spray drying process was studied in a parallel study and the efficacy of some sugar based excipients in protection of antibodies was studied. Results: The SDS-PAGE analysis showed no fragmentation of antibodies after spray drying in all formulations. The secondary structure of antibodies contained 40.13 to 70.19% of β structure in dry state. Also, CD spectroscopy showed the similar secondary structure for trastuzumab after reconstitution in water. ELISA analysis and cell culture studies were conducted in order to evaluate bioactivity of monoclonal antibody. Formulations containing combination of excipients provided maximum tendency of trastuzumab to attach to the ELISA antigen (86.46% ± 2.3) and maximum bioactivity when incubated with SKBr3 cell line (the cell viability was decreased to 65.99%± 4.6). Incubation of formulations with L929 cell line proved the biocompatibility of the excipients and non-toxic composition of formulations. Conclusion: The IgG1 and trastuzumab demonstrated similar behavior in spray drying process. The combination of excipients containing trahalose, hydroxypropyl beta cyclodextrin and beta cyclodextrin with proper ratio improved the physical and chemical stability of both IgG1 and monoclonal antibody

Evaluation of the Clinical, Laboratory and Imaging Findings of Patients with COVID-19 and Their Associations with Clinical Outcomes in an Iranian Hospital: A Cross-Sectional Study

Background: Coronavirus disease 2019 (COVID-19) is a concern in the medical community as the virus spreads around the world. It has a heavy global burden, particularly in low-income countries. This virus has its specific outcomes in each population. Hence, it is necessary to design studies to find the epidemiological behaviour of this virus. Materials and Methods: This cross-sectional study was conducted in the Labbafinezhad hospital, Tehran, Iran. Demographic features include age, sex, past medical history, drug history, habitual file, influenza vaccination history, recent exposure history, clinical symptoms or signs, and the recorded symptoms. The clinical examination and para-clinical assessment, including chest computed tomography (CT) and laboratory testing on admission, were recorded. Results: It was found that patients with a history of kidney transplantation, high level of LDH, high level of AST, and increased neutrophil to lymphocyte ratio are most at risk of death. Conclusion: Parameters mentioned could help practitioners predict patient outcomes, and necessary interventions could be considered in this regard

Mapping 123 million neonatal, infant and child deaths between 2000 and 2017

Since 2000, many countries have achieved considerable success in improving child survival, but localized progress remains unclear. To inform efforts towards United Nations Sustainable Development Goal 3.2—to end preventable child deaths by 2030—we need consistently estimated data at the subnational level regarding child mortality rates and trends. Here we quantified, for the period 2000–2017, the subnational variation in mortality rates and number of deaths of neonates, infants and children under 5 years of age within 99 low- and middle-income countries using a geostatistical survival model. We estimated that 32% of children under 5 in these countries lived in districts that had attained rates of 25 or fewer child deaths per 1,000 live births by 2017, and that 58% of child deaths between 2000 and 2017 in these countries could have been averted in the absence of geographical inequality. This study enables the identification of high-mortality clusters, patterns of progress and geographical inequalities to inform appropriate investments and implementations that will help to improve the health of all populations

Development of IgY-Based Sandwich ELISA as a Robust Tool for Rapid Detection and Discrimination of Toxigenic Vibrio cholerae

Background. The conventional methods for diagnosis of Vibrio cholerae are time consuming, complicated, and expensive. Development of rapid detection tests is critical for prevention and management of cholera. This study aimed to introduce two sensitive sandwich ELISAs based on avian antibodies (IgY) targeting outer membrane protein W (OmpW) and cytotoxin B (CtxB) antigens of V. cholerae. Methods. The sequences of ompW and ctxB genes were cloned into pET28a vector. Escherichia coli BL21 (DE3) was transformed with the recombinant vectors, and gene expression was induced by IPTG. The expressed proteins were purified by affinity chromatography using Ni-NTA resins. Two groups of white Leghorn chickens were immunized by recombinant proteins, and the generated antibodies were purified from egg yolks of chickens by PEG precipitation. The antibodies were used for the development of α-OmpW and α-CtxB ELISAs. Results. The expression and purification yielded 59 and 38 mg of recombinant OmpW and CtxB, respectively, per one liter of bacterial culture. PEG precipitation and purification of egg yolk antibodies yielded on average (±SD) 66.5 ± 1.80 and 50.9 ± 2.23 mg of purified α-OmpW and α-CtxB per egg, respectively. The analytical sensitivity of α-OmpW ELISA was 103 cfu/mL of V. cholerae and that of α-CtxB ELISA was 33 pg/mL of recombinant cytotoxin B. The two developed ELISAs did not show any cross-reactivity to any tested bacteria grown in common conditions. Discussion. The current study is the first report on using IgY for detection of V. cholerae. The developed ELISAs were shown to have considerable analytical sensitivity and specificity. Therefore, the assays can be one of the convenient methods for sensitive and specific detection of toxigenic V. cholerae strains in clinical and environmental samples

Compositional changes of PBL population in patients with chronic hepatitis B virus infection

In this report we have analysed the peripheral blood lymphocyte of several patients with chronic hepatitis B virus infection with flow cytometry. Based on the presence and absence of the HBeAb, patients were divided into two groups. In both, all the patients were HBsAg positive with normal range of serum alanine aminotranferase (23.9 ± 17.8). We have found that the immunophenotypic profiles of patients were different from healthy donors with significant decrease in CD3+ T cells, specially CD8+ T cells and a siginificant increase in the CD19+ B cells. The differences were seen in other subset of T cells (CD4+) or NK cells (CD56+/CD16+ ) and HLA-DR markers were not significant. When the phenotypic profiles of both groups were compared with each other, such changes were more dominant in group II, with HBeAb positive than in group I, with HBeAb negative. Also, we have seen a correlation between the increase of CD19+ B cells and the decrease of CD3+ T cells. No such correlation was observed with other cells