Related Experiment Video
Updated: Feb 26, 2026

T Cells Capture Bacteria by Transinfection from Dendritic Cells
Published on: January 13, 2016
Innate scavenger receptor-A regulates adaptive T helper cell responses to pathogen infection
Zhipeng Xu1, Lei Xu1, Wei Li1
1Jiangsu Province Key Laboratory of Modern Pathogen Biology, Department of Pathogen Biology and Immunology, Nanjing Medical University, Nanjing, Jiangsu 210029, China.
Abstract:
The pattern recognition receptor (PRR) scavenger receptor class A (SR-A) has an important function in the pathogenesis of non-infectious diseases and in innate immune responses to pathogen infections. However, little is known about the role of SR-A in the host adaptive immune responses to pathogen infection. Here we show with mouse models of helminth Schistosoma japonicum infection and heat-inactivated Mycobacterium tuberculosis stimulation that SR-A is regulated by pathogens and suppresses IRF5 nuclear translocation by direct interaction. Reduced abundance of nuclear IRF5 shifts macrophage polarization from M1 towards M2, which subsequently switches T-helper responses from type 1 to type 2. Our study identifies a role for SR-A as an innate PRR in regulating adaptive immune responses.
Related Concept Videos
Cell-mediated Immune Responses
Immune Response Against Viral Pathogens
NK Cells
NK cells are a crucial part of our innate immune system, acting as the first line of defense against viral infections. These cells can recognize and kill infected cells without prior exposure to the virus, effectively slowing down the spread of infection. Additionally, NK cells produce proinflammatory...
Introduction to Innate and Adaptive Immunity
Innate immunity is the body's natural, nonspecific defense system that acts quickly to protect against pathogens. It incorporates physical barriers like skin and mucous membranes and cellular elements such as phagocytes and natural killer cells. This part of our immune system provides an immediate,...
Defense Against Bacterial Pathogens
Phagocytes
Phagocytes are the frontline soldiers of the immune system. They include neutrophils and macrophages. Neutrophils are the most abundant type of white blood cell and are quickly mobilized to the site of infection. Macrophages are larger cells that patrol...
Diversity of Antigen Receptors
Before encountering any antigen, lymphocytes express these receptors. On B cells, the antigen receptor is a membrane-bound antibody molecule called BCR; on T cells, it is a T cell receptor or TCR. B and T cell receptors are composed of two...
Antigens Involved in Adaptive Immunity
Complete Antigens
Complete antigens possess both immunogenicity and...

