immune evasion
Research Article | Host-Microbe BiologyBacterial Pathogens Hijack the Innate Immune Response by Activation of the Reverse Transsulfuration PathwayMacrophages are professional immune cells that ingest and kill microbes. In this study, we show that different pathogenic bacteria induce the expression of cystathionine γ-lyase (CTH) in macrophages. This enzyme is involved in a metabolic pathway called the reverse transsulfuration pathway, which leads to the production of numerous metabolites, including cystathionine. Phagocytized bacteria use cystathionine to better survive in...
Research Article | Host-Microbe BiologyKingella kingae Surface Polysaccharides Promote Resistance to Neutrophil Phagocytosis and KillingKingella kingae is a Gram-negative commensal in the oropharynx and represents a leading cause of joint and bone infections in young children. The mechanisms by which K. kingae evades host innate immunity during pathogenesis of disease remain poorly understood. In this study, we established that the...
Research Article | Host-Microbe BiologyTrogocytosis by Entamoeba histolytica Mediates Acquisition and Display of Human Cell Membrane Proteins and Evasion of Lysis by Human SerumEntamoeba histolytica causes amoebiasis, a potentially fatal diarrheal disease. Abscesses in organs such as the liver can occur when amoebae are able to breach the intestinal wall and travel through the bloodstream to other areas of the body. Therefore, understanding how E. histolytica evades immune...
Research Article | Host-Microbe BiologyHuman Influenza A Virus Hemagglutinin Glycan Evolution Follows a Temporal Pattern to a Glycan LimitFrequent mutation of its major antibody target, the glycoprotein hemagglutinin, ensures that the influenza virus is perennially both a rapidly emerging virus and a major threat to public health. One type of mutation escapes immunity by adding a glycan onto an area of hemagglutinin that many antibodies recognize. This study revealed that these glycan changes follow a simple temporal pattern. Every 5 to 7 years, hemagglutinin adds a new...
Research Article | Molecular Biology and PhysiologyStructural Constraints at the Trimer Apex Stabilize the HIV-1 Envelope in a Closed, Antibody-Protected ConformationThe extraordinary ability of human immunodeficiency virus type 1 (HIV-1) to evade host immunity represents a major obstacle to the development of a protective vaccine. Thus, elucidating the mechanisms whereby HIV-1 protects its external envelope (Env), which is the sole target of virus-neutralizing antibodies, is an essential step toward vaccine design. We identified a key structural element that maintains the HIV-1 Env trimer in a...
Research Article | Host-Microbe BiologyEvasion of Immune Surveillance in Low Oxygen Environments Enhances Candida albicans VirulenceSuccessful human colonizers have evolved mechanisms to bypass immune surveillance. Infiltration of PMNs to the site of infection led to the generation of a low oxygen niche. Exposure to low oxygen levels induced fungal cell wall masking, which in turn hindered pathogen sensing and antifungal responses by PMNs. The cell wall masking effect was prolonged by increasing lactate amounts produced by neutrophil metabolism under oxygen...
Research Article | Host-Microbe BiologyA Secreted Bacterial Peptidylarginine Deiminase Can Neutralize Human Innate Immune DefensesBacterial pathogens do not only succeed in breaking the barriers that protect humans from infection, but they also manage to evade insults from the human immune system. The importance of the present study resides in the fact that protein citrullination is shown to represent a new bacterial mechanism for immune evasion. In particular, the oral pathogen P. gingivalis...