Characterization of Tumor-Associated Antigens on Human Oral Squamous Cell Carcinomas Using Monoclonal Antibody 3F8E3

Abstract

Tumor associated antigen (TAA) on oral squamous cell carcinoma (SCC) was characterized using the monoclonal antibody (MAb) 3F8E3. Flow cytometric analysis revealed a varying degree of reactivity of MAb 3F8E3 to TAA on oral tumor cells. Pretreatment of SCC cells with pronase and trypsin annulled the reactivity of MAb 3F8E3. Sodium metaperiodate (NaIO4) and neuraminidase marginally enhanced the binding of 3F8E3 on oral SCC cells. The studies indicate that the TAA recognized by MAb 3F8E3 on oral tumors is a protein moiety. On Western blotting MAb 3F8E3 showed reactivity to proteins with a molecular weight of 60-66 kDa on oral tumor lysates. MAb 3F8E3 reacted strongly to recombinant human hsp60 and 70 in ELISA. The results suggest that MAb 3F8E3 may react to an epitope expressed on a family of heat shock proteins.

Changes in the Immunologic Phenotype of Human Malignant Glioma Cells after Passaging in Vitro

“…The tissue was promptly washed with cold phosphate-buffered saline (PBS), manually minced, and then enzymatically digested with 400 g/ml of DNase I and 1 mg/ml of collagenase IV (Worthington Biochemical Corp., Freehold, NJ) for 30 min in a humidified tissue culture incubator (5% CO 2 , 37°C). Trypsin dispersion was avoided because trypsin has been shown to degrade many cell surface molecules on antigen-presenting cells including MHC class I (48), intercellular adhesion molecule-1 (ICAM-1) (49, 50), VCAM-1 (49), E-selectin (49), CD38 (51), epidermal growth factor receptor (52), and lipopolysaccharide binding site (53), as well as specific tumor-associated antigens (50,54,55). Disruption of cells with collagenase and DNase, however, has minimal effects on cell surface expression (48).…”

Role of nitric oxide in heat shock protein induced apoptosis of γδT cells

“…γδT cells were incubated either with Daudi cells, Raji cells (negative control) or oral tumor cells (1:0.5) for 16 hr at 37°C. After incubation, Daudi cells and Raji cells were separated using anti‐CD21 MAb (BD Pharmingen) and oral tumor cells were separated using anti‐SCC MAb (clone 3F8E3)11 by immunomagnetic purification. Cells were fixed with 70% ethanol and were washed thrice with phosphate‐buffered saline (PBS).The pellet was resuspended in 0.3 ml PBS, 100 μl of propidium iodide (50 μg/ml; Sigma) and 100 μl of RNase (100 μg/ml; Sigma) and incubated for 30 min at room temperature under agitation.…”