title: A study of the functional capabilities of human neonatal lymphocytes for in vitro specific antibody production.
abstract: The ability of neonatal B and T cells to participate in the in vitro production of anti-influenza virus antibody was studied. Peripheral blood mononuclear cells from nearly all normal adults produce anti-influenza virus antibody when stimulated in vitro with type A influenza virus. Cord blood mononuclear cells, however, consistently failed to do so. Using Epstein-Barr virus activation or coculture with irradiated adult T cells in the presence of influenza virus to identify precursor B cells for anti-viral antibody production, newborns were found to have a decreased number of influenza-specific B cells as compared with adults. Thus, a paucity of precursor B cells for anti-influenza virus antibody was one factor contributing to the absent in vitro antibody response. Additional studies were undertaken to investigate the capabilities of newborn T cells in the in vitro response to influenza virus. Newborn T cells failed to proliferate when cultured with influenza virus. Irradiated newborn T cells were, however, able to provide help for specific antibody production in influenza virus-stimulated cocultures with allogeneic adult B cells, and newborn T cells proliferated when stimulated with alloantigens; their helper function in allogeneic coculture was, thus, likely mediated by T cells stimulated by alloantigens rather than by influenza virus. In the absence of T cell irradiation, no antibody was produced in cocultures of adult B cells and neonatal T cells, at least in part as the result of a radiosensitive suppressor T cell. Suppression in influenza virus-stimulated allogeneic cocultures was also observed with normal adult T cells and is, therefore, a property of both newborn and adult T cells. Thus, allogeneic help and suppression can both be manifested in exogenous antigen-stimulated allogeneic cocultures. In addition, both of these allogeneic effects can be mediated by neonatal T cells, indicating that these functions are present at the time of birth and do not require previous exogenous antigenic exposure for expression.
mesh_terms: D000328:Adult; D000914:Antibodies, Viral / Q000096:biosynthesis*; D001402:B-Lymphocytes / Q000276:immunology*; D002472:Cell Transformation, Viral; D005312:Fetal Blood / Q000166:cytology / Q000276:immunology*; D004854:Herpesvirus 4, Human / Q000276:immunology; D006801:Humans; D007231:Infant, Newborn; D007251:Influenza, Human / Q000276:immunology; D008213:Lymphocyte Activation; D008211:Lymphocyte Cooperation; D007959:Lymphocyte Culture Test, Mixed; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000914:Antibodies, Viral