ABSTRACT
A gene of human tumor-associated antigen VNTR(MUC1) bound to streptavidin, an expression plasmid, and a highly effective hybrid protein-producing strain were constructed. It was shown that the streptavidin leader peptide ensures an effective secretion of the hybrid protein into the periplasmic space of Escherichia coli cells. The hybrid protein was isolated in a homogeneous state and its immunogenic properties were studied.
Subject(s)
Antigens, Neoplasm/genetics , Escherichia coli/genetics , Mucin-1/genetics , Streptavidin/genetics , Amino Acid Sequence , Base Sequence , DNA, Recombinant , Humans , Minisatellite Repeats , Molecular Sequence Data , Plasmids , Recombinant Fusion Proteins/geneticsABSTRACT
A conjugate was developed between ricin A-chain and monoclonal antiallotypic antibody specific for L-chains of the rat Ig. Incubation of spleen cells with the conjugate (10(-7) M) resulted in a strong decrease of 1a-positive B-lymphocyte growth. At the same time spleen cells that lacked this antigen were not affected by immunotoxin (IT). Both the isolated antibodies and ricin A-chain did not inhibit cell growth in the same concentrations. IT injection to 10-day-old heterozygous rats (1a/1b) resulted in a partial suppression of Ig production with 1a-allotype. The conjugate was 4.5 times more effective than the isolated antibodies used to form it. The in vivo and in vitro differences in IT cytotoxicity were probably connected with insufficient efficacy of conjugate targeting in vivo.
Subject(s)
Cytotoxicity, Immunologic , Immunoglobulin Allotypes/immunology , Immunoglobulin lambda-Chains/immunology , Immunotoxins/immunology , Animals , Antibodies, Monoclonal/immunology , Antibody Specificity , B-Lymphocytes/growth & development , Cells, Cultured , Rats , Ricin/immunology , Spleen/cytology , Spleen/immunologyABSTRACT
A simplified method of beta 2-microglobulin (beta 2-M) separation from the urine of patients with Fanconi's syndrome and renal transplantation is proposed. The process of isolation includes column chromatrography with the use of molsect G-25, Sephadex G-100 and DEAE-Sephadex A-25. The yield of purified beta 2-M (92.3 +/- 2.85%) was equal to 3% of its initial amount in the urine.