Pep34, a synthetic peptide whose sequence corresponds to the intracytoplasmic domain of the Epstein-Barr virus receptor (CR2, CD21), regulates human B lymphocyte proliferation triggered through CR2.
CR2 is involved in regulation of human B lymphocyte proliferation by interacting, through distinct domains, with extracellular, cell surface or intracellular components. Contribution of CR2 intracytoplasmic domain in CR2 regulatory functions remains unclear. Thus, we used pep34, a 34 amino acid synthetic peptide whose sequence corresponds to CR2 intracytoplasmic domain. Pep34 was incorporated into B lymphocytes which were then activated by EBV or C3d through CR2. Our data demonstrate that pep34 inhibits 100% B lymphocyte proliferation triggered by EBV or C3d. Irrelevant peptide had no effect. When B lymphocyte proliferation was triggered by a multipotent B cell activator as SAC, pep34 did not exert any inhibitory effect. Our data demonstrate that pep34 inhibits B lymphocyte proliferation only when lymphocytes are triggered through CR2. Thus, this strongly supports that despite its short length. CR2 intracytoplasmic domain participates to regulatory functions of this receptor.
Balbo
M
M
INSERM U.354, Centre INSERM, Hôpital Saint-Antoine, Paris, France.
Barel
M
M
Bouillie
S
S
Drane
P
P
Cassinat
B
B
Frade
R
R
D000595:Amino Acid Sequence; D001402:B-Lymphocytes / Q000187:drug effects / Q000378:metabolism*; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D006801:Humans; D008969:Molecular Sequence Data; D010455:Peptides / Q000138:chemical synthesis / Q000494:pharmacology*; D017464:Receptors, Complement 3d / Q000737:chemistry / Q000378:metabolism*; D011991:Receptors, Virus / Q000737:chemistry / Q000378:metabolism*
D010455:Peptides; D017464:Receptors, Complement 3d; D011991:Receptors, Virus