Localization of endogenous beta-galactoside-binding lectin in human cells and tissues.

A rabbit antiserum raised against the 14.5-kilodalton (kDa) subunit of human splenic galaptin was used to probe protein blots of several tissue extracts. For all tissues examined, the only immunoreactive species detected was a 14.

Galactoside-binding lectin in human tissues.

Lactose-inhibitable lectin activity has been analyzed by hemagglutination assay in a variety of human tissues and cells obtained at surgery and autopsy. The lectin activity was detected in surgically removed melanoma, sarcoma, colon carcinoma, breast carcinoma, adjacent non-malignant tissues, non-malignant tissues obtained at autopsy and in cells isolated from malignant effusions. Although, on average, malignant tissue had a higher hemagglutinating titer than non-malignant tissue, similar tissues from different individuals varied widely in their apparent lectin content.

In vitro synthesis of carbohydrate-binding proteins by human leucocytes.

A carbohydrate-binding protein (CBP) synthesized in vitro by normal human peripheral leucocytes was isolated by affinity chromatography on asialofetuin-Sepharose. The CBP was eluted with lactose and it had a native molecular mass of 15,500 daltons. Analysis by SDS-PAGE revealed a single polypeptide of 18,000 daltons.

A study of the specificity of Bandeiraea simplicifolia lectin I by competitive-binding assay with blood-group substances and with blood-group A and B active and other oligosaccharides.

The specificity of Bandeiraea simplicifolia lectin I (BS I) has been studied by competitive-binding assays (CBA) using tritium-labeled human B and hog A substances. Blood-group B substances isolated from horse gastric mucosae and from human ovarian-cyst fluids were much better inhibitors of binding of tritiated blood-group B substance to insoluble BS I-Sepharose 2B than were human blood-group A substances from saliva and ovarian-cyst fluid. A and B active blood-group substances showed the same range of potency in inhibiting binding of tritium-labeled hog A substance to BS I-Sepharose 2B.

Immunochemical studies on blood groups LXVI. Competitive binding assays of A1 and A2 blood group substances with insolubilized anti-A serum and insolubilized A agglutinin from Dolichos biflorus.

Competitive binding assays using 3H-labeled blood group A substance and insolubilized Dolichos biflorus lectin or human anti-A were carried out, measuring competition by blood group A1 and A2 glycoproteins, and by unabsorbed anti-A sera, and with these sera absorbed with the A1 and A2 glycoproteins. With Dolichos lectin specific for (formula: see text) A1 substances had about 11 times as many determinants as did A2 substances, but the slopes of the lines in the competitive binding assays were the same. With insolubilized anti-A, A2 substances gave lines of lower slopes.