THE NUCLEOTIDE SEQUENCE OF THE GENES, fanE AND fanF, OF Escherichia coli K99 FIMBRIAE

K99 fimbriae of enterotoxigenic Escherichia coli consist of eight different subunits. A major subunit called fimbrillin forms fimbrial structure and a minor subunit called adhesin localizes at the tip of fimbriae and recognizes host receptor ganglioside. Within this eight gene cluster, fanE and fanF have not yet been sequenced. In this study, fanE and fanF genes were sequenced by analyzing several DNA fragments produced by endonuclease or exonuclease digestion. The fanE gene encoded 227 amino acids containing 20 amino acids of signal peptide starting from GTG (valine) and showed a homology to fanA-fanB. The fanF gene encoded 271 amino acids containing 20 amino acids of signal peptide starting from ATG (methionine) and showed homologies to the fanD gene, fimbrillin gene of F41,adhesin gene of P fimbriae (papG) and adhesin gene of Type 1 fimbriae (fimH). E and F subunits had fifteen and fourteen hydrophobic domains, respectively, which periodically appeared possibly forming a hydrophobic region

ELEVATION OF HETEROPHILIC ANTIBODIES TO RABBIT ERYTHROCYTES IN HUMAN PATHOLOGIC SERA : QUANTITATIVE STUDIES BY ELISA USING A GLYCOSPHINGOLIPID ANTIGEN

Human heterophilic hemagglutinin to rabbit erythrocytes was quantitatively determined by the hemagglutination test and enzyme linked immunosorbent assay (ELISA) using rabbit erythrocyte pentaglycosyl ceramide (CPH), Gal (α 1-3) Gal (β 1-4) GlcNAc (β 1-3) Gal (β 1-4) Glc-Cer as the antigen. The antibody levels in sera from 74 Hanganutziu-Deicher (H-D) antibody-positive patients were significantly higher than those in sera from 55 healthy donors, and the correlation between the antibody levels detected by ELISA and hemagglutinin titers was significant. The antibody levels detected by ELISA correlated to the IgG antibody levels, while the hemagglutinin titers correlated to the IgM antibody levels. These results suggested that IgG levels as well as IgM levels against rabbit erythrocytes were elevated in H-D antibody-positive patients with various tumors and infectious diseases. In 4 out of 67 cancer patients collected randomly, abnormally high levels of anti-CPH IgG antibody were detected

USE OF BIOTINYLATED ANTIBODY FOR THE ASSAY OF HANGANUTZIU-DEICHER ANTIBODIES AND ANTIGENS IN FLUIDS AND TISSUES FROM CANCER PATIENTS

An improved enzyme-linked immunosorbent assay (ELISA) for detection of heterophile Hanganutziu-Deicher (HD) antibodies and antigens, which are frequently detected in sera and/or cancerous tissues from patients with various cancers was developed using biotinylated chicken anti-GM3(NeuGc) antibody and avidin-horse raddish peroxidase conjugate. The N-glycolylneuraminyllactosyl-ceramide, GM3(NeuGc) ganglioside was purified from horse erythrocyte memberanes. The ELISA proceduure required 300 ng GM3(NeuGc) antigen to coat plastic microtiter plates and 190 ng biotinylated antibody per well to give optimum product formation. The technique could detect 6 ng antigen in tissue homogenate as compared to 0.6 ng of the pure compound by inhibition. Chicken anti-GM3(NeuGc) antibody quantitatively inhibited the biotinylated antibody, however, this procedure was not suitable to quantify lower affinity HD antibody in patient sera. Immunostaining specific for HD antigen-positive cells, in tissue sections was by 4 μg/ml biotinylted antibody and 200 dilution of Avidin-biotinylated peroxidase complex reagent using pig intestine and lymph node as positive tissues and chicken intestine and lung as negative tissues