title: Pregnancy-associated growth factor. II. A T-dependent polyclonal activator of human adult peripheral blood lymphocytes (PBL).
abstract: This study examined the ability of pregnancy-associated growth factor (PAGF), a substance found in crude human chorionic gonadotropin (hCG), to induce plaque-forming cells (PFC) in cultured human peripheral blood lymphocytes (PBL). PAGF, 0.25 to 1 mg/ml, induced maximal PFC at 6 to 7 days as measured by the staphylococcal protein A-coupled SRBC reverse hemolytic plaque assay with a rabbit anti-human Ig antiserum. PAGF-induced PFC/culture ranged from 1800 to 39,000 with a mean of 11,524 in unfractionated PBL (N = 24), as compared to 540 to 77,840 with a mean of 17,303 for pokeweed (PWM) (N = 22). Comparison of PAGF- and PWM-induced PFC showed that both induced specific IgG, IgA, and IgM PFC. In most individuals, PAGF induced more IgM and PWM more IgG PFC. The kappa: lambda ratio was 1.5 for unstimulated PBL, and approximately 3.5 for PAGF and PWM. To see if PAGF was a T-dependent polyclonal activator of B cells, T and non-T populations were obtained by SRBC rosettes and negatively selected T4 and T8 cells by complement-mediated lysis of SRBC+(T) cells. Only the recombined subsets which included T4 cells and non-T cells supported PAGF- and PWM-induced PFC. These data indicate that PAGF, a substance derived from commercial extracts of pregnancy urine, is a T4-dependent polyclonal activator of normal human B cells.
authors.forename: J A
authors.initials: JA
authors.lastname: Carlino
authors.forename: J H
authors.initials: JH
authors.lastname: Morse
mesh_terms: D000328:Adult; D001402:B-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D005260:Female; D006462:Hemolytic Plaque Technique; D006801:Humans; D007070:Immunoglobulin A / Q000096:biosynthesis; D007126:Immunoglobulin Allotypes / Q000096:biosynthesis; D007074:Immunoglobulin G / Q000096:biosynthesis; D007075:Immunoglobulin M / Q000096:biosynthesis; D008213:Lymphocyte Activation; D008297:Male; D010641:Phenotype; D011257:Pregnancy Proteins / Q000502:physiology*; D013601:T-Lymphocytes / Q000145:classification / Q000276:immunology*; D000511:alpha-Macroglobulins / Q000502:physiology*
chemical_list: D007070:Immunoglobulin A; D007126:Immunoglobulin Allotypes; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D011257:Pregnancy Proteins; D000511:alpha-Macroglobulins; C032306:polyclonal B cell activator; C034156:pregnancy-associated growth factor