A B cell-restricted activation antigen (B8.7) functionally related to the low molecular weight B cell growth factor receptor.
A novel monoclonal antibody (anti-B8.7) is reported which recognizes an epitope expressed either on in vitro activated B cells or on a fraction of fresh large B cells (putatively in vivo preactivated). B8.7 antigen is also present on two out of eight B cell lines tested and is characterized as a membrane component displaying an approximate molecular weight of 55,000 to 60,000. By contrast, B8.7 is absent from resting B cells, monocytes, resting or activated T cells, and from the eight non-B cell lines tested. After in vitro activation, B8.7 antigen appears later than the transferrin receptor and its expression increases until day 3. The anti-B8.7 monoclonal antibody induces a dose-related inhibition of the low molecular weight B cell growth factor-dependent proliferation of activated B cells, whereas it does not affect their response to interleukin 2. This strongly suggests that the B8.7 epitope is present on a molecule selectively involved in the interaction between B cells and a B cell growth factor.
Leprince
C
C
Institut National de la Santé et de la Recherche Médicale (INSERM) U 131, Clamart, France.
Richard
Y
Y
Krief
P
P
Treton
D
D
Boucheix
C
C
Galanaud
P
P
D000911:Antibodies, Monoclonal / Q000276:immunology*; D000944:Antigens, Differentiation, B-Lymphocyte / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology*; D001681:Biological Assay; D015847:Interleukin-4; D007378:Interleukins / Q000502:physiology*; D008213:Lymphocyte Activation; D008970:Molecular Weight; D009439:Neuraminidase; D011402:Pronase; D019948:Receptors, Interleukin-4; D011975:Receptors, Mitogen / Q000502:physiology*; D014357:Trypsin
D000911:Antibodies, Monoclonal; D000944:Antigens, Differentiation, B-Lymphocyte; D007378:Interleukins; D019948:Receptors, Interleukin-4; D011975:Receptors, Mitogen; D015847:Interleukin-4; D009439:Neuraminidase; D014357:Trypsin; D011402:Pronase