Medical Microbiology and Immunology This is an RSS file. You can use it to subscribe to this data in your favourite RSS reader or to display this data on your own website or blog.

Antibody Fc-binding profiles and ACE2 affinity to SARS-CoV-2 RBD variants
AbstractEmerging SARS-CoV-2 variants, notably Omicron, continue to remain a formidable challenge to worldwide public health. The SARS-CoV-2 receptor-binding domain (RBD) is a hotspot for mutations, reflecting its critical role at the ACE2 interface during viral entry. Here, we comprehensively investigated the impact of RBD mutations, including 5 variants of concern (VOC) or interest —including Omicron (BA.2)—and 33 common point mutations, both on IgG recognition and ACE2-binding inhibition, as well as FcγRIIa- and FcγRIIIa-binding antibodies, in plasma from two-dose BNT162b2-vaccine recipients and mild-COVID-19 conva...
Source: Medical Microbiology and Immunology - July 21, 2023 Category: Microbiology Source Type: research

Correction to: Picking up speed: cell cycle regulation during effector CD8+ T cell differentiation
(Source: Medical Microbiology and Immunology)
Source: Medical Microbiology and Immunology - June 21, 2023 Category: Microbiology Source Type: research

Association of IFIH1 and DDX58 genes polymorphism with susceptibility to COVID-19
AbstractPattern recognition receptors of the innate immune system, such as RIG-I and MDA5, are responsible for recognizing viruses and inducing interferon production. Genetic polymorphisms in the coding regions of RLR may be associated with the severity of COVID-19. Considering the contribution of the RLR signaling in immune-mediated reactions, this study investigated the association between three SNP in the coding region of  IFIH1 and DDX58 genes with the susceptibility to COVID-19 in the Kermanshah population, Iran. 177 patients with severe and 182 with mild COVID-19 were admitted for this study. Genomic DNA was extr...
Source: Medical Microbiology and Immunology - June 13, 2023 Category: Microbiology Source Type: research

Innate immune response in patients with acute Chikungunya disease
AbstractChikungunya disease (CHIKD) is an arbovirose that presents with high morbidity, mainly due to arthralgia. Inflammatory mediators including IL-6, IL-1 β, GM-CSF and others have been implicated in the pathogenesis of CHIKD, whilst type I interferons can be associated with better outcomes. The role of pattern recognition receptors has been studied incompletely. Here, we evaluated the expression of RNA-specific PRRs, their adaptor molecules and down stream cytokines in acute CHIKD patients. Twenty-eight patients were recruited during the 3rd–5th day after the symptoms onset for clinical examination, peripheral blood...
Source: Medical Microbiology and Immunology - June 7, 2023 Category: Microbiology Source Type: research

Pentraxin 3, a serum biomarker in human T-cell lymphotropic virus type-1-associated myelopathy patients and asymptomatic carriers
AbstractHuman T-cell lymphotropic virus type 1 (HTLV-1) can induce a neuroinflammatory condition that leads to myelopathy. Pentraxin 3 (PTX3) is an acute-phase protein that its plasma concentration increases during inflammation. We aimed to determine whether PTX3 serum level is elevated in HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) patients and HTLV-1 asymptomatic carriers (ACs) and evaluate its association with proviral load and clinical features. The serum level of PTX3 was measured using an enzyme-linked immunosorbent assay in 30 HAM patients, 30 HTLV-1 ACs, and 30 healthy controls. Also, the HT...
Source: Medical Microbiology and Immunology - June 6, 2023 Category: Microbiology Source Type: research

Picking up speed: cell cycle regulation during effector CD8+ T cell differentiation
AbstractClonal expansion and development of immunological memory are two hallmarks of adaptive immune responses. Resolving the intricate pathways that regulate cell cycle activity and lead to the generation of diverse effector and memory T cell subsets is essential for improving our understanding of protective T cell immunity. A deeper knowledge of cell cycle regulation in T cells also has translational implications for adoptive cell therapies and vaccinations against infectious diseases. Here, we summarize recent evidence for an early diversification of effector and memory CD8+ T cell fates and discuss how this process is...
Source: Medical Microbiology and Immunology - June 6, 2023 Category: Microbiology Source Type: research

Gene biomarkers and classifiers for various subtypes of HTLV-1-caused ATLL cancer identified by a combination of differential gene co ‑expression and support vector machine algorithms
AbstractAdult T-cell leukemia/lymphoma (ATLL) is pathogen-caused cancer that is progressed after the infection by human T-cell leukemia virus type 1. Four significant subtypes comprising acute, lymphoma, chronic, and smoldering have been identified for this cancer. However, there are no trustworthy prognostic biomarkers for these subtypes. We utilized a combination of two powerful network-based and machine-learning algorithms including differential co-expressed genes (DiffCoEx) and support vector machine-recursive feature elimination with cross-validation (SVM-RFECV) methods to categorize disparate ATLL subtypes from asymp...
Source: Medical Microbiology and Immunology - May 24, 2023 Category: Microbiology Source Type: research

Trimer stability of Helicobacter pylori HtrA is regulated by a natural mutation in the protease domain
AbstractThe human pathogenHelicobacter pylori is a major risk factor for gastric disease development. Serine protease HtrA is an important bacterial virulence factor that cleaves the cell junction proteins occludin, claudin-8 and E-cadherin, which causes gastric tissue damage. Using casein zymography, we discovered that HtrA trimer stability varies in clinicalH. pylori strains. Subsequent sequence analyses revealed that HtrA trimer stability correlated with the presence of leucine or serine residue at position 171. The importance of these amino acids in determining trimer stability was confirmed by leucine-to-serine swappi...
Source: Medical Microbiology and Immunology - May 14, 2023 Category: Microbiology Source Type: research

Phenotypic and genotypic identification of carbapenem resistance in Bacteroides fragilis clinical strains
AbstractBacteroides fragilis is an important etiological agent of serious infections in humans. Rapid methods, readily adaptable to use in medical laboratories, are needed to detect antibiotic resistance and decrease the likelihood of therapy failure. The aim of this study was to determine the prevalence ofB. fragilis cfiA-positive isolates. The second purpose was to investigate the carbapenemase activity inB. fragilis strains by Carba NP test. In the study, 5.2% ofB. fragilis isolates are phenotypically resistant to meropenem. ThecfiA gene was identified in 6.1% ofB. fragilis isolates. The MICs of meropenem were significa...
Source: Medical Microbiology and Immunology - May 13, 2023 Category: Microbiology Source Type: research

The quantity and quality of anti-SARS-CoV-2 antibodies show contrariwise association with COVID-19 severity: lessons learned from IgG avidity
This study aimed to evaluate the avidity of serum IgG antibodies against SARS-CoV-2 spike (S) and nucleocapsid (N) in hospitalized symptomatic COVID-19 patients and asymptomatic RT-PCR-confirmed SARS-CoV-2 carriers as well as to compare antibody avidities with respect to vaccination status, vaccination dose and reinfection status. Serum levels of anti-S and anti-N IgG were determined using specific ELISA kits. Antibody avidity was determined by urea dissociation assay and expressed as avidity index (AI) value. Despite higher IgG levels in the symptomatic group, AI values of both anti-S and anti-N IgG were significantly low...
Source: Medical Microbiology and Immunology - April 27, 2023 Category: Microbiology Source Type: research

Detection of DENV-2 and ZIKV coinfection in southeastern Brazil by serum and urine testing
ConclusionBy testing serum and urine samples, we increased the detection of both viruses and detected considerable levels of ZIKV and DENV-2 coinfection when compared to other studies. Additionally, we detected an unnoticed ZIKV outbreak in the city. These findings highlight the importance of the molecular diagnosis of arboviruses to aid public health surveillance and management strategies. (Source: Medical Microbiology and Immunology)
Source: Medical Microbiology and Immunology - April 7, 2023 Category: Microbiology Source Type: research

Editorial on special issue on “Immunobiology of Viral Infections”
(Source: Medical Microbiology and Immunology)
Source: Medical Microbiology and Immunology - March 30, 2023 Category: Microbiology Source Type: research

IgG antibody response to pneumococcal-conjugated vaccine (Prevenar ®13) in children with immunodeficiency disorders
AbstractMeasurement of anti-pneumococcal capsular polysaccharides (anti-PnPs) IgG titers is an important tool in the immunologic assessment of patients with suspected immunodeficiency disorders (ID) to reduce the morbi-mortality and minimize severe infections. Retrospectively, we studied the relationship among anti-PnPs IgG response to 3 doses of Prevenar ®13, levels of immune system components, leukocyte populations, and clinical data in children with ID. Serum samples were collected at least 4 weeks post vaccination. Subsequently, multi-serotype enzyme-linked immunosorbent assay (ELISA) was performed. Eighty-seven chil...
Source: Medical Microbiology and Immunology - January 3, 2023 Category: Microbiology Source Type: research

Intrinsic D614G and P681R/H mutations in SARS-CoV-2 VoCs Alpha, Delta, Omicron and viruses with D614G plus key signature mutations in spike protein alters fusogenicity and infectivity
AbstractThe SARS-CoV-2 virus has been rapidly evolving over the time and the genetic variation has led to the generation of Variants of Concerns (VoC), which have shown increased fitness. These VoC viruses contain the key mutations in the spike protein which have allowed better survival and evasion of host defense mechanisms. The D614G mutation in the spike domain is found in the majority of VoC; additionally, the P681R/H mutation at the S1/S2 furin cleavage site junction is also found to be highly conserved in major VoCs; Alpha, Delta, Omicron, and its ’ current variants. The impact of these genetic alterations of the S...
Source: Medical Microbiology and Immunology - December 30, 2022 Category: Microbiology Source Type: research

A high CMV-specific T cell response associates with SARS-CoV-2-specific IL-17  T cell production
AbstractHuman cytomegalovirus (CMV) is a widespread persistent herpes virus requiring lifelong immune surveillance to maintain latency. Such long-term interactions with the immune system may be associated with deleterious effects including immune exhaustion and senescence. Regarding the COVID-19 pandemic, we asked whether CMV-specific cellular and humoral activity could influence immune responses toward SARS-CoV-2 and/or disease severity. All adults with mild (n = 15) and severe (n = 14) COVID-19 were seropositive for anti-CMV IgG, but negative for IgM antibodies. Antibody titers did not correlate with COVID-19 sev...
Source: Medical Microbiology and Immunology - December 13, 2022 Category: Microbiology Source Type: research