Co-housing with dirty mice increases the frequency of memory T cells and has variable effects on intracellular bacterial infection

• Published in: ImmunoHorizons 2022-02, Vol.6 (2), p.184-190
• Main Authors: Labuda, Jasmine C., Fong, Kevin D., McSorley, Stephen J.
• Format: Article
• Language: English
• ISSN: 2573-7732
• DOI: 10.4049/immunohorizons.2100069

The presence of memory lymphocytes in non-lymphoid tissues reflects prior immunological experience and can provide non-specific defense against infection. Here, we used a mouse cohousing approach to examine the effect of prior immunological experience on Salmonella and Chlamydia infection. As expected, co-housing of “dirty mice” with SPF laboratory mice increased the frequency of effector memory T cells (T EM ) in laboratory mice and enhanced protection against systemic Listeria infection. In contrast, the course of systemic infection with Salmonella and mucosal infection with Chlamydia was largely unaffected by co-housing, despite enhanced frequencies of memory T cells. Thus, co-housing of laboratory mice reliably increases the proportion of memory T cells in circulation, but can have variable effects on pathogen clearance.