Distal IgA immunity can be sustained by αEβ7+ B cells in L-selectin−/− mice following oral immunization
- Pascual, D. W. [ Montana State University: Microbiology & Cell Biology ]
- Riccardi, C. [ Montana State University: Microbiology & Cell Biology ]
- Csencsits-Smith, K.
Understanding the role of homing receptors could aid vaccine strategies for developing distal mucosal immunity. Infection studies have revealed that immune intestinal B cells use α4β7 homing receptors, but their role in subsequent oral immunization with soluble antigens is unknown. To assess the influence of L-selectin and α4β7 on distal B cells following oral cholera toxin (CT) immunization, L-selectin-deficient (L-Sel−/−) IgA anti-CT-B-specific B cells were enhanced 30-, 9.2-, and 3.5-fold in head and neck lymph nodes (HNLNs), nasal-associated lymphoid tissue, and nasal passages (NPs), respectively, vs. L-Sel+/+ mice. Cell-sorted intestinal and NP IgA antibody-forming cells (AFCs) were mostly α4β7+, unlike HNLN L-Sel−/− IgA and IgG anti-CT-B AFCs that were αEβ7+, contrasting with L-Sel+/+ HNLN IgA AFCs that were mostly α4β7+. In vitro studies revealed that L-Sel−/− HNLN B cells preferentially expressed αE following polyclonal stimulation. These studies show that HNLN B cells express αEβ7 in the absence of L-selectin to sustain distal IgA responses.