Mast cells in response to some pathogens elicit a transcriptional program devoid of type I IFN response
Ontology highlight
ABSTRACT: Although mast cells elicit proinflammatory and type I IFN responses upon VSV infection, in response to L.monocytogenes (L.m) or S. Typhimurium (S.t), such cells elicit a transcriptional program devoid of type I IFN response. Balanced induction of proinflamatory and type I interferon (IFN) responses upon activation of Toll like receptors (TLRs) determines the outcome of microbial infections and the pathogenesis of autoimmune and other inflammatory diseases. Mast cells, key components of the innate immune system, are known for their debilitating role in allergy and autoimmune syndromes. However, their potential role in anti-microbial host defenses is increasingly being acknowledged. How mast cells interact with microbes and the nature of responses triggered thereof is not well characterized. Here we show that in response to TLR activation by Gram-positive and negative bacteria or their components like LPS, unlike macrophages, mast cells elicit pro-inflammatory but not type I IFN responses. We demonstrate that in mast cells, the bound bacteria and TLR ligands remain trapped at the cell surface and do not undergo internalization - a prerequisite for type I IFN induction. Such cells could, however, elicit type I IFNs in response to vesicular stomatitis virus (VSV), which accesses the cytosolic RIG-I receptor. Although important for anti-viral immunity, a strong type I IFN response is known to contribute to pathogenesis during bacterial infection. Thus, while endowed with the capacity to elicit type I IFNs in response to viral infection, the fact that mast cells only elicit pro-inflammatory responses upon bacterial infection illustrates that mast cells, key effector cells of the innate immune system, are well adjusted for optimal anti-bacterial and anti-viral responses.
ORGANISM(S): Mus musculus
PROVIDER: GSE18500 | GEO | 2009/12/31
SECONDARY ACCESSION(S): PRJNA120249
REPOSITORIES: GEO
ACCESS DATA