This paper presents data on reactions of murine macrophages with a variety of lectins, with special focus on Griffonia simplicifolia I-B4 isolectin, the only lectin we tried that distinguishes stimulated macrophages from resident populations. Specificity of Gniffonia simplicifolia I reaction with carbohydrate determinants at the cell surface is shown by (i) ability of a-galactosidase treatment of intact cells to abolish all lectin binding whereas .-galactosidase has no effect on lectin binding, (ii) ability ofmethyl a-D-galactopyranoside to completely inhibit lectin binding with methyl a-D-glucopyranoside having no effect on lectin binding, (iii) ability of brief treatment of intact cells with trypsin to liberate a glycopeptide that reacts with G. simplicifolia I to form a precipitate that is dissolved by addition ofmethyl a-D-galactopyranoside or a-galactosidase but not by addition of methyl a-D-glucopyranoside or /3-galactosidase, (iv) ability of methyl a-D-galactopyranoside (but no other monosaccharide) to completely inhibit avid binding of macrophages to G. simplicifolia I lectin immobilized on an insoluble support, and (v) ability of immobilized lectin to separate macrophages into highly pure subpopulations of lectin-reactive and lectin-unreactive cells, as shown by examination offluorescein-labeled lectin-treated cells with phase-contrast/ fluorescence microscopy. During investigations on the surface glycoproteins of the Ehrlich ascites tumor cell and their interactions with lectins, it was observed that intraperitoneal injection of Griffonia simplicifolia § lectin I (GSI) at the time of intraperitoneal inoculation with Ehrlich tumor gave virtually complete protection of the animal against growth of the tumor. This paper reports on one phase of subsequent work directed at elucidation of the mech-

No abstract

Previous studies have indicated that a galactosephilic component present on the bacterial cell surfaces of Streptococcus sanguis ATCC 10557 may be responsible for the salivary glycoprotein‐medtated binding of the cells. The purpose of this study was to investigate the purification and characterization of galactosephilic cell surface component from S. sanguis ATCC 10557. A galactosephilic component involving fibrils on the cell surfaces was isolated by the techniques of freezing and thawing, and purified by an affinity chromatography on β‐d‐galactose binding‐Bio‐Gel P‐2 followed by gel filtrations on Bio‐Gel P‐150 and on Bio‐Gel P‐30. Both disk gel electrophoresis and sodium dodecyl sulfate‐polyacrylamide gel electrophoresis showed that the purified product was homogeneous. The isoelectric point of the purified sample was 8.5 to 9.0. Treatment of the purified sample with pronase E reduced remarkably either the hemagglutinating activity or the precipitation reaction with proline‐rich glycoprotein in human parotid saliva, suggesting that the active site may be present on the peptide moieties. When sugar specificity was examined by hemagglutination‐inhibition test, d‐galactose was the strongest inhibitor. The results of this study suggest that the galactosephilic component may be a bacterial lectin.

Alkaline phosphatase conjugated oligonucleotide probes were developed to detect the genes (tdh and trh) coding for the thermostable direct hemolysin (TDH) and TDH-related hemolysin (TRH) of Vibrio parahaemolyticus. Using dot blot hybridization, probes were tested with 94 clinical isolates of V. parahaemolyticus. Results agreed well with those obtained using radio-labeled recombinant DNA probes for the genes tdh and trh. Specificity and sensitivity of enzyme tdh probes for detection of the trh gene were 100 and 93%, respectively, and those of the trh probes for trh gene detection were 93 and 86%, respectively. The tdh probes also hybridized with tdh-like genes processed by all strains of V. hollisae, and some strains of V. mimicus and V. cholerae non-O1, but neither tdh nor trh probes reacted with other bacterial species isolated from diarrheal stools. However, some V. parahaemolyticus strains that were negative with the enzyme trh probe hybridized weakly with a radio-labeled trh DNA fragment probe at medium stringency, and a few strains that were negative in high stringency conditions with a radio-labeled trh DNA fragment probe hybridized with the enzyme trh probe. This suggests that some strains of V. parahaemolyticus may carry another gene resembling trh.

Leaves from mature Griffonia supficifolia plants were examined for the presence of leaf lectins possessing sugar binding specificities similar to the four known seed lectins (GS