Isolation and analysis of lectin-reactive sarcoma-associated membrane glycoproteins

Sarcoma and normal tissue plasma membrane lectin-reactive glycoproteins were analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Two peanut agglutinin-reactive N-acetylgalactosamine-containing glycoproteins of 1.05 x 10(6) and 1.25 x 10(5) Da and one lentil agglutinin-reactive mannose/N-acetylglucosamine(-fucose)/sialic acid-containing glycoprotein of 1.7 x 10(5) Da (Gp170) were detected in osteosarcoma and malignant fibrous histiocytoma (MFH), respectively. However, these glycoproteins were not detected in normal tissue plasma membranes. Concanavalin A, wheat germ and Ulex europaeus Type I agglutinins did not reveal any unique sarcoma-associated membrane glycoproteins. Preliminary studies on monoclonal antibodies (mAbs) generated against Gp170 (mAb 64-35-84) and against lentil-reactive glycoproteins from MFH (mAbs 67-34 and 67-117) revealed high specific binding to a number of membranes isolated from MFH and osteosarcoma tissues, with no crossreactivity to normal human tissues tested (liver, spleen and skin). Detailed analysis of mAb 67-102, which was generated against lentil-reactive glycoproteins isolated from MFH plasma membranes, exhibited significant binding to membranes isolated from osteosarcoma, liposarcoma and MFH; moderate binding to synovial sarcoma, aggressive fibromatosis and fibrosarcoma; and minimal to no binding to other soft tissue sarcoma plasma membranes. No binding was observed to twenty normal tissue specimens, with the exception of low positive binding to two of five fat and two of three colon specimens.