Nasal cholera toxin elicits IL-5 anel IL-5 receptor α-chain expressing B-1a B cells for innate mucosal IgA antibody responses

Academic Article

Abstract

  • In this study, we examine whether native cholera toxin (nCT) as a mucosal adjuvant can support trinitrophenyl (TNP)-LPS-specific mucosal immune responses. C57BL/6 mice were given nasal TNP-LPS in the presence or absence of nCT. Five days later, significantly higher levels of TNP-specific mucosal IgA Ab responses were induced in the nasal washes, saliva, and plasma of mice given nCT plus TNP-LPS than in those given TNP-LPS alone. High numbers of TNP-specific IgA Ab-forming cells were also detected in mucosal tissues such as the nasal passages (NPs), the submandibular glands (SMGs), and nasopharyngeal-associated lymphoreticular tissue of mice given nCT. Flow cytometric analysis showed that higher numbers of surface IgA+, CD5+ B cells (B-1a B cells) in SMGs and NPs of mice given nasal TNP-LPS plus nCT than in these given TNP-LPS alone. Furthermore, increased levels of IL-5R α-chain were expressed by B-1a B cells in SMGs and NPs of mice given nasal TNP-LPS plus nCT. Thus, CD4+ T cells from these mucosal effector lymphoid tissues produce high levels of IL-5 at both protein and mRNA levels. When mice were treated with anti-IL-5 mAb, significant reductions in TNP-specific mucosal IgA Ab responses were noted in external secretions. These findings show that nasal nCT as an adjuvant enhances mucosal immune responses to a T cell-independent Ag due to the cross-talk between IL-5Rα+ B-1a B cells and IL-5-producing CD4+ T cells in the mucosal effector lymphoid tissues. Copyright © 2037 by The American Association of Immunologists, Inc.
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    Digital Object Identifier (doi)

    Author List

  • Kataoka K; Fujihashi K; Sekine S; Fukuiwa T; Kobayashi R; Suzuki H; Nagata H; Takatsu K; Shizukuishi S; McGhee JR
  • Start Page

  • 6058
  • End Page

  • 6065
  • Volume

  • 178
  • Issue

  • 10