Characterization of a human antigen specific helper factor

Conference · Sat Mar 01 04:00:00 EST 1986 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)

OSTI ID:5508798

Richardson, B

While antigen (Ag) specific helper factors have been characterized in mice, similar molecules have not been identified in humans. To characterize human antigen specific helper molecules, an IL-2 dependent tetanus toxoid (T.T.) reactive T cell line was fused with a 6-thioguanine resistant CEM line, and hybrids selected in medium containing hypoxanthine and azaserine. Hybrids were screened by culturing the cells with /sup 35/S-Met then reacting the supernatants with T.T. or hepatitis vaccine immobilized on nitrocellulose. One hybrid, TT6BA-O, was identified which secreted a Met-containing molecule which bound T.T. but not hepatitis vaccine. Supernatants from TT6BA-O, but not the parent CEM line, when added to autologous peripheral blood mononuclear cells (PBMC's) stimulated secretion of T.T. specific antibodies (Abs). Specificity controls demonstrated that TT6BA-O supernatant did not induce antibodies to diphtheria toxoid, hepatitis vaccine or pneumococcal polysaccharide, and total immunoglobulin (lg) synthesis was minimally increased. In contrast, pokeweed mitogen stimulated significant lg synthesis as well as Ab's to pneumococcal polysaccharide and T.T. TT6BA-O supernatant induced anti-T.T.Ab's in autologous PBMC's but not PBMC's from 3 unrelated donors, suggesting that the activity of the helper factor is restricted, possibly by the MHC. The molecular weight of the helper factor was estimated at 100,000-150,000 by Sephacryl S-300 chromatography. Finally, the helper factor could be demonstrated to bind and elute from sephorose-immobilized T.T. and anti-DR antisera, but not anti-lg antisera or the T40/25 monoclonal antibody, which binds a nonpolymorphic determinant on the human T cell receptor. These results demonstrate that human Ag specific helper factors exist, bind antigen and bear class II MHC determinants.

• Research Organization: Univ. of Michigan, Ann Arbor
• OSTI ID: 5508798
• Report Number(s): CONF-8604222-
• Conference Information: Journal Name: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States) Journal Volume: 45:3
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ANIMAL CELLS
ANTIBODIES
ANTIGENS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOCHEMICAL REACTION KINETICS
BIOLOGICAL MATERIALS
BIOSYNTHESIS
BLOOD
BLOOD CELLS
BLOOD COAGULATION FACTORS
BODY FLUIDS
CELL CULTURES
CHROMATOGRAPHY
COAGULANTS
CONNECTIVE TISSUE CELLS
DAYS LIVING RADIOISOTOPES
DIGESTIVE SYSTEM DISEASES
DISEASES
DRUGS
EVEN-ODD NUCLEI
GLOBULINS
HEMATOLOGIC AGENTS
HEPATITIS
IMMUNOGLOBULINS
ISOTOPE APPLICATIONS
ISOTOPES
KINETICS
LEUKOCYTES
LIGHT NUCLEI
LYMPHOCYTES
MATERIALS
MEMBRANE PROTEINS
MOLECULAR WEIGHT
MOLECULES
MONOCLONAL ANTIBODIES
NUCLEI
ORGANIC COMPOUNDS
PROTEINS
RADIOISOTOPES
REACTION KINETICS
RECEPTORS
SEPARATION PROCESSES
SOMATIC CELLS
SULFUR 35
SULFUR ISOTOPES
SYNTHESIS
TRACER TECHNIQUES