Inhibition of murine B cell proliferation and down-regulation of protein kinase C levels by a phosphorylcholine-containing filarial excretory-secretory product.
E-S 62, a major excretory-secretory product of the rodent filarial parasite, Acanthocheilonema viteae, inhibits the polyclonal activation (DNA synthesis) of mouse B cells by mitogenic anti-Ig antibodies. This effect appears to be due at least in part to the phosphorylcholine (PC) moiety of the molecule, because it can be mimicked by PC-BSA or PC-chloride. Activation of the B cells by LPS is not influenced by the presence of E-S 62/PC, suggesting that they may target some aspect of signaling via the Ag receptor. E-S 62/PC failed to inhibit surface Ig-mediated generation of the second messenger, inositol triphosphate, indicating that their target may not be the early biochemical events associated with activation. Exposure to E-S 62/PC was found to lead to a reduction in the level of protein kinase C, an important downstream regulatory enzyme, in anti-Ig-treated cells. This protein-kinase C down-regulation may be the biochemical mechanism underlying E-S 62/PC-mediated inhibition of surface Ig-activated B cells.
Harnett
W
W
Department of Immunology, University of Strathclyde, Glasgow, UK.
Harnett
M M
MM
D000818:Animals; D000947:Antigens, Helminth / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology*; D002478:Cells, Cultured; D004153:Dipetalonema / Q000276:immunology*; D015536:Down-Regulation; D005849:Gerbillinae; D008070:Lipopolysaccharides / Q000494:pharmacology; D008213:Lymphocyte Activation; D051379:Mice; D008807:Mice, Inbred BALB C; D008808:Mice, Inbred CBA; D010767:Phosphorylcholine / Q000494:pharmacology*; D011493:Protein Kinase C / Q000378:metabolism*
D000947:Antigens, Helminth; D008070:Lipopolysaccharides; D010767:Phosphorylcholine; D011493:Protein Kinase C