Human appendix B cells naturally express receptors for and respond to interleukin 6 with selective IgA1 and IgA2 synthesis.

Abstract

Past studies have shown that freshly isolated human B cells from peripheral blood and tonsils do not express IL-6 receptors (IL-6R); however, mitogen or antigen activation of these B cells induces IL-6R and responsiveness to IL-6. In this study, we have shown that a high proportion of B cells enzymatically dissociated from human appendix, a gut-associated lymphoreticular tissue (GALT), expresses the IL-6R, and that recombinant human IL-6 induces significant increases in the number of Ig-producing cells. The recombinant human IL-6-induced increase in Ig-producing 1991. 88:248-252.)

Induction of inflammation as a possible mechanism of probiotic effect in atopic eczema–dermatitis syndrome

“…22 In the gut mucosa IL-6 regulates mucosal total protein synthesis, as well as IgA production by Peyer's patch B cells, and induces an increase in the number of IgA-producing cells in B cells of the human appendix. 23,24 This might explain our earlier findings that LGG treatment resulted in an increase in fecal IgA levels in infants with IgE-associated CMA. 25 IL-6 also acts on endothelial cells to promote upregulation of sICAM-1 and sE-selectin.…”

CD11b+ Peyer’s Patch Dendritic Cells Secrete IL-6 and Induce IgA Secretion from Naive B Cells

“…IL-6 markedly and selectively enhances IgA production in vitro by isotype-committed B cells (21,29). It has been reported that mice with targeted disruption of the gene encoding IL-6 mount very poor IgA responses in the intestine and lungs, but that this defect can be overcome following vector-directed IL-6 gene therapy (22).…”

Immune Responses to Novel Pneumococcal Proteins Pneumolysin, PspA, PsaA, and CbpA in Adenoidal B Cells from Children

“…It is generally thought that IgA is predominant in mucosal areas (18,32) and that IgG mainly provides systemic protection. However, recent studies have shown that in both adenoids and tonsils, IgG-secreting cells are predominant (6), which is different from the main induction and effector sites in the gastrointestinal tract (i.e., Peyer's patches and the lamina propria), where the majority of B cells secrete IgA (18,32). The large numbers of IgG-and IgA-secreting cells in the epithelial and subepithelial compartments of adenoids and tonsils suggest that they have characteristics of effector sites and that IgG could be a significant component of local mucosal responses (6).…”