Article
Mucosal Immunology (2008) 1, 68–77. doi:10.1038/mi.2007.2
Distal IgA immunity can be sustained by 
E
7+ B cells in L-selectin-/- mice following oral immunization
D W Pascual1, C Riccardi1 and K Csencsits-Smith2
- 1Department of Veterinary Molecular Biology, Montana State University, Bozeman, Montana, USA
- 2Department of Pathology and Laboratory Medicine, Chemical Immunology Research Center, University of Texas Health Science Center at Houston, Houston, Texas, USA
Correspondence: DW Pascual, (dpascual@montana.edu)
Received 9 March 2007; Accepted 13 June 2007.
Abstract
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 
4
7 homing receptors, but their role in subsequent oral immunization with soluble antigens is unknown. To assess the influence of L-selectin and 47 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 47+, unlike HNLN L-Sel-/- IgA and IgG anti-CT-B AFCs that were E7+, contrasting with L-Sel+/+ HNLN IgA AFCs that were mostly 47+. In vitro studies revealed that L-Sel-/- HNLN B cells preferentially expressed E following polyclonal stimulation. These studies show that HNLN B cells express E7 in the absence of L-selectin to sustain distal IgA responses.
