Antigen-specific primary immune response of human B-lymphocytes after in vitro immunization with GM3 ganglioside.
In vitro immunization of human B-lymphocytes was performed with liposomes containing the monosialoganglioside GM3, with or without either complete tetanus toxoid or a synthetic T helper epitope derived from tetanus toxin (determinant 830-843). The immunized B-cells were Epstein-Barr virus transformed and the human anti-ganglioside antibody response was evaluated using an indirect ELISA against different mono- and disialogangliosides. Clones producing antigen-specific human antibodies of the IgM isotype against the ganglioside GM3 used as the immunogen were selected and one clone, IM-11, was further characterized. In addition, a method of positive selection using GM3-coated magnetic beads has been developed which allowed us to rescue unstable clones. The binding of the human antibody IM-11 to a large panel of glycosphingolipids separated on thin-layer plates was studied. The human MAb IM-11 was found to bind strongly to NeuAcGM3, IV3 NeuAcnLc4 and sulfate containing glycosphingolipids and weakly to NeuGcGM3. Immunohistological staining of melanoma and breast cancer biopsy sections showed a selective reactivity of IM-11 with tumor cells which varied among different tumors.
Alfonso
M
M
Center of Molecular Immunology, Dept. of Research and Development, Havana, Cuba.
Lanne
B
B
Ifversen
P
P
Vázquez
A M
AM
Pérez
R
R
Portoukalian
J
J
Zeuthen
J
J
D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal / Q000096:biosynthesis / Q000276:immunology*; D000951:Antigens, Neoplasm / Q000032:analysis; D001402:B-Lymphocytes / Q000276:immunology*; D001943:Breast Neoplasms / Q000276:immunology; D002240:Carbohydrate Sequence; D005679:G(M3) Ganglioside / Q000276:immunology*; D006801:Humans; D007114:Immunization; D008545:Melanoma / Q000276:immunology; D008969:Molecular Sequence Data
D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm; D005679:G(M3) Ganglioside