Measurement of the Memory B Cell Response via Antibodies from Activated Cells.

Background/objectives: The body's immune response to infections and vaccination leads to the formation of memory B cells (MBCs), which protect against future infections. MBCs circulate in the blood, and the strength of the MBC response is measured with different tests. In this study, tests to measure the MBC response were compared.

Serological Evidence of Zika Virus Infections in Sudan.

Little is known about the frequency of Zika virus (ZIKV) infections in Sudan. The aim of this study was to obtain data on the prevalence of ZIKV infections and the immunity of the population in the country. To this end, 198 sera obtained between December 2012 and January 2013 in different regions in Sudan were examined for neutralizing antibodies against ZIKV, dengue virus (DENV), and yellow fever virus (YFV).

Potential of a Bead-Based Multiplex Assay for SARS-CoV-2 Antibody Detection.

Serological assays for SARS-CoV-2 play a pivotal role in the definition of whether patients are infected, the understanding of viral epidemiology, the screening of convalescent sera for therapeutic and prophylactic purposes, and in obtaining a better understanding of the immune response towards the virus. The aim of this study was to investigate the performance of a bead-based multiplex assay. This assay allowed for the simultaneous testing of IgG antibodies against SARS-CoV-2 spike, S1, S2, RBD, and nucleocapsid moieties and S1 of seasonal coronaviruses hCoV-22E, hCoV-HKU1, hCoV-NL63, and hCoV-OC43, as well as MERS and SARS-CoV.

Pediatric cancer patients vaccinated against SARS-CoV-2-a clinical and laboratory follow-up.

Background: Vaccination against SARS-CoV-2 is recommended for cancer patients. However, long-term data on the effectiveness in the pediatric setting are lacking.

Methods: Pediatric patients < 18 years on active treatment for cancer and without prior SARS-CoV-2 infection received three doses of an mRNA vaccine.

Low BAU/ml values with 4 of 5 SARS CoV-2 spike-specific monoclonal antibodies in the Roche Elecsys antibody assay.

Background: The Abbott SARS-CoV-2 IgG Quant II assay and the Roche Elecsys double antigen sandwich (DAgS) immunoassay measure SARS-CoV-2 receptor binding domain (RBD)-specific antibodies in serum samples in different ways. The IgG Quant II assay uses an antigen in combination with a secondary antibody and the DAgS assay uses two antigens. The aim of the study was to investigate whether the assays give comparable results with monoclonal antibodies.

Diagnostic Specificity of Two Dengue Virus IgG ELISAs after Yellow Fever and Japanese Encephalitis Virus Vaccination.

Dengue virus (DENV) antibody assays frequently cross-react with sera from individuals who have been infected with or vaccinated against related flaviviruses. The goal of this study was to determine the specificity of two DENV ELISAs with sera from individuals vaccinated against yellow fever virus (YFV) and Japanese encephalitis virus (JEV). The Panbio and the Novatec Dengue IgG ELISAs were tested with sera obtained 3-4 weeks or 0.

Comparison of the measured values of quantitative SARS-CoV-2 spike antibody assays.

Background: The concentration of antibodies against the SARS-CoV-2 spike protein is frequently being measured for clinical and epidemiological purposes. The aim of this study was to examine whether the results of different quantitative SARS-CoV-2 spike antibody assays are comparable.

Material And Methods: The Siemens SARS-CoV-2 IgG, Abbott SARS-CoV-2 IgG II Quant, Roche ElecsysT Anti-SARS-CoV-2 S, and Euroimmun Anti-SARS-CoV-2-QuantiVac assay were compared with 110 sera from patients 6-9 months after SARS-CoV-2 infection and the WHO First International SARS-CoV-2 antibody standard 20/136.

West Nile Virus Seroprevalence and Cross-Neutralization in Sera from Eastern and Central Sudan.

In regions with co-existing flaviviruses, the diagnosis of previous West Nile virus (WNV) infections is challenging due to cross-reacting antibodies. The aim of the study was to determine the frequency of previous WNV infections in sera from three Sudanese states by excluding potentially dengue virus (DENV) and ZIKV cross-reacting sera and to determine the percentage of WNV cross-neutralizing sera from individuals with previous DENV infection. Serum samples from Kassala, North Kordofan, and Red Sea state were screened for antibodies against DENV by ELISA.

Longitudinal Immune Response to 3 Doses of Messenger RNA Vaccine Against Coronavirus Disease 2019 (COVID-19) in Pediatric Patients Receiving Chemotherapy for Cancer.

Our study in 21 pediatric cancer patients demonstrates that 3 doses of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) messenger RNA vaccine (BioNTech/Pfizer) elicited both humoral and cellular immunity in most patients during chemotherapy. Immunity was stronger in children with solid tumors and during maintenance therapy compared to those with hematological malignancies or during intensive chemotherapy. Clinical Trials Registration.

Cytotoxicity of Medicinal Plant Species Used by Traditional Healers in Treating People Suffering From HIV/AIDS in Uganda.

Many people living with HIV/AIDS (PLHIV) in Uganda widely use herbal medicines. However, their toxicity and safety have not been investigated. The use of these plants can potentially cause harmful effects to the health of patients.

Sensitivity of SARS-CoV-2 antibody tests with late convalescent sera.

SARS-CoV-2-specific IgM antibodies wane during the first three months after infection and IgG antibody levels decline. This may limit the ability of antibody tests to identify previous SARS-CoV-2 infection at later time points. To examine if the diagnostic sensitivity of antibody tests falls off, we compared the sensitivity of two nucleoprotein-based antibody tests, the Roche Elecsis II Anti-SARS-CoV-2 and the Abbott SARS-CoV-2 IgG assay and three glycoprotein-based tests, the Abbott SARS-CoV-2 IgG II Quant, Siemens Atellica IM COV2T and Euroimmun SARS-CoV-2 assay with 53 sera obtained 6 months after SARS-CoV-2 infection.

Antibody Course and Memory B-Cell Response in the First Year After Severe Acute Respiratory Syndrome Coronavirus 2 Infection.

Background: The possibility of repeat infections with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) raises questions regarding quality and longevity of the virus-induced immune response.

Methods: The antibody course and memory B-cell (MBC) response against SARS-CoV-2 proteins, influenza virus nucleoprotein (NP), and tetanus toxin were examined in adults with mild to moderate SARS-CoV-2 infection in the first year after infection.

Results: The concentration of SARS-CoV-2 receptor binding domain (RBD)-specific antibodies was low compared with the concentration of influenza virus NP-specific antibodies.

Epidemiology and Laboratory Diagnostics of Dengue, Yellow Fever, Zika, and Chikungunya Virus Infections in Africa.

Arbovirus infections are widespread, and their disease burden has increased in the past decade. In Africa, arbovirus infections and fever with unknown etiology are common. Due to the lack of well-established epidemiologic surveillance systems and accurate differential diagnosis in most African countries, little is known about the prevalence of human arbovirus infections in Africa.

Performance of a SARS CoV-2 antibody ELISA based on simultaneous measurement of antibodies against the viral nucleoprotein and receptor-binding domain.

SARS CoV-2 antibody assays measure antibodies against the viral nucleoprotein (NP) or spike protein. The study examined if testing of antibodies against both antigens increases the diagnostic sensitivity. Sera (N=98) from infected individuals were tested with ELISAs based on the NP, receptor-binding domain (RBD), or both proteins.

A Review of the Toxicity and Phytochemistry of Medicinal Plant Species Used by Herbalists in Treating People Living With HIV/AIDS in Uganda.

Despite concerns about toxicity, potentially harmful effects and herb-drug interactions, the use of herbal medicines remains widely practiced by people living with HIV/AIDS (PLHIV) in Uganda. The objective of the paper was to comprehensively review the literature on the toxicity and chemical composition of commonly used medicinal plant species in treating PLHIV in Uganda. We reviewed relevant articles and books published over the last sixty years on ethnobotany, antiviral/anti-HIV activity, toxicity, phytochemistry of , , , , , , , , , and and their synonyms.

Comparison of the diagnostic sensitivity of SARS-CoV-2 nucleoprotein and glycoprotein-based antibody tests.

The emergence of the severe acute respiratory syndrome coronavirus-2 (SARS CoV-2) has been followed by the rapid development of antibody tests. To assess the utility of the tests for clinical use and seroepidemiologic studies, we examined the sensitivity of commercial antibody tests from Roche, Abbott, Novatec, Virotech Siemens, Euroimmun, and Mediagnost in a prospective diagnostic study. The tests were evaluated with 73 sera from SARS CoV-2 RNA positive individuals with mild to moderate disease or asymptomatic infection.

Development and Potential Usefulness of the COVID-19 Ag Respi-Strip Diagnostic Assay in a Pandemic Context.

COVID-19 Ag Respi-Strip, an immunochromatographic (ICT) assay for the rapid detection of SARS-CoV-2 antigen on nasopharyngeal specimen, has been developed to identify positive COVID-19 patients allowing prompt clinical and quarantine decisions. In this original research article, we describe the conception, the analytical and clinical performances as well as the risk management of implementing the COVID-19 Ag Respi-Strip in a diagnostic decision algorithm. Development of the COVID-19 Ag Respi-Strip resulted in a ready-to-use ICT assay based on a membrane technology with colloidal gold nanoparticles using monoclonal antibodies directed against the SARS-CoV and SARS-CoV-2 highly conserved nucleoprotein antigen.

Adapting epicutaneous patch testing protocols to assess immediate-type skin reactions.

Objective: During the development of cosmetic formulations, in vitro and in vivo methods are essential tools used to reliably assess the skin irritation potential of a product or ingredient. Epicutaneous patch testing (single and/or multiple application protocols) has long been used as an initial in vivo method to screen for possible skin irritation properties of a substance or formulation. To confirm the mildness and dermatological and/or consumer acceptance of a product, use tests are often subsequently conducted.

[Navigation in medical research].

Education of medical students requires teaching students how to navigate in the broad field of medical research. The objective of this article is to provide an overview about medical research and to show how to denote a medical study in a concise fashion. Medical research can be classified into categories according to the object of investigation.

Enhancing the concordance of two commercial dengue IgG ELISAs by exchange of the calibrator sample.

Background: Dengue IgG testing is being recommended before dengue vaccination. Presently, the diagnostic method of choice is the dengue IgG ELISA.

Objective: Determine the test performance and concordance of two commercial dengue IgG ELISA kits.

Zika virus: mapping and reprogramming the entry.

Background: The flaviviridae family comprises single-stranded RNA viruses that enter cells via clathrin-mediated pH-dependent endocytosis. Although the initial events of the virus entry have been already identified, data regarding intracellular virus trafficking and delivery to the replication site are limited. The purpose of this study was to map the transport route of Zika virus and to identify the fusion site within the endosomal compartment.

Elevated Human Crimean-Congo Hemorrhagic Fever Virus Seroprevalence in Khashm el Girba, Eastern Sudan.

Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne disease that can evolve into deadly hemorrhagic fever and that is endemic in many parts of Europe, Middle East, Central Asia, and Africa. Because of several reports about CCHF outbreaks in the south of Sudan during the last years, we examined in this study if unrecognized CCHF-V infections also occurred in the eastern and central parts of the country. The study examined the seroprevalence of CCHF virus infection in 464 sera from three regions of Sudan without previous reports of CCHF infection.

High seroprevalence of dengue virus indicates that dengue virus infections are frequent in central and eastern Sudan.

Objectives: To determine the seroprevalence of dengue in central and eastern Sudan and the breadth of neutralising antibody responses.

Methods: Blood was drawn from 483 patients with fever who visited outpatient clinics in Port Sudan, Red Sea state, in three towns in Kassala state and in El Obeid, North Kordofan, in December 2012 and January 2013. Sera were tested for dengue virus IgG and IgM by ELISA (Panbio) and sera without serologic evidence of acute infection (IgM negative) were used for the analysis of the seroprevalence.

Low Seroprevalence Indicates Vulnerability of Eastern and Central Sudan to Infection with Chikungunya Virus.

Outbreaks of infections with chikungunya virus (CHIKV) have previously been reported from Sudan but the prevalence in the general population is unknown. We investigated the seroprevalence of CHIKV infection in 379 serum samples from patients with fever in the outpatient clinics of three hospitals in eastern and central Sudan. The seroprevalence was 1.