A 16 amino acid synthetic peptide derived from human C3d triggers proliferation and specific tyrosine phosphorylation of transformed CR2-positive human lymphocytes and of normal resting B lymphocytes.
We demonstrate herein that p16, a 16 amino acid synthetic peptide derived from human C3d, which carried LYNVEA sequence of C3d reacting with CR2 and C3d present in trypsin-cleaved C3, triggered "in vitro" and "in vivo" phosphorylations and "in vitro" proliferation of human B lymphocytes, depending on the stage of cell differentiation. Indeed, p16 and C3dT induced "in vivo" tyrosine phosphorylation of pp105 and "in vitro" proliferation only of CR2-positive and not of CR2-negative cell lines. In addition, p16 and C3dT also induced "in vivo" tyrosine phosphorylation of pp100 and "in vitro" proliferation of only small dense resting B lymphocytes and not other B lymphocyte subpopulations nor T lymphocytes. These data suggest that induction of pp100 and pp105 phosphorylation by p16 and C3dT could represent an early event associated with expression of CR2 in the regulation of human B lymphocyte proliferation.
Frade
R
R
Immunochimie des Régulations Cellulaires et des Interactions Virales, INSERM U.354, Hôpital Saint-Antoine, Paris, France.
Hermann
J
J
Barel
M
M
D000595:Amino Acid Sequence; D001402:B-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D002051:Burkitt Lymphoma; D002455:Cell Division / Q000187:drug effects; D002461:Cell Line, Transformed; D015933:Complement C3d / Q000138:chemical synthesis / Q000494:pharmacology*; D006801:Humans; D007700:Kinetics; D008213:Lymphocyte Activation / Q000187:drug effects*; D016399:Lymphoma, T-Cell; D008969:Molecular Sequence Data; D010455:Peptides / Q000138:chemical synthesis / Q000494:pharmacology*; D010766:Phosphorylation; D017464:Receptors, Complement 3d / Q000276:immunology*; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology
D010455:Peptides; D017464:Receptors, Complement 3d; D015933:Complement C3d