Monoclonal Antibody Specifically Reacting against 73-Kilodalton Heat Shock Cognate Protein: Possible Expression on Mammalian Cell Surface

Abstract

The heat shock proteins (hsp) are regarded as being immunogenic to the animal hosts. Although certain hsp are suggested to be expressed on the cell surface, further evidence for the cell surface expression of these proteins has been required. In this article we report the development of a MAb NT22. This antibody reacted with ATP-binding proteins (which contain a large amount of 70-kDa hsp family) of HeLa cells, and with purified bovine 70-kDa hsp. It did not react with the E. coli lysate, but clearly reacted with the recombinant rat hsc73. However, NT22 failed to react with hsp72. Furthermore, stress treatment of cells also indicated that considerable amounts of NT22-defined antigen translocated into the nucleus from the cell cytoplasm. These results suggest that NT22 is a novel MAb that reacts specifically to the mammalian hsc73. Moreover, this antibody could detect the constitutive and stress-induced cell surface expression of its relevant antigen. It is expressed preferentially on EBV-transformed B cell and certain epithelial cancer cell lines. However, resting B cells did not express this antigen on the cell surface. These data indicate that hsc73 could be expressed on the cell surface of certain cells, and suggest that hsc73 may interact with the host immune system.

Monoclonal antibody to novel cell surface epitope on Hsc70 promotes morphogenesis of bile ducts in newborn rat liver

“…MAb OC.10 reacted strongly with PepSPOTS 1-8 and 15-17 that correspond to amino acids 340-366 and 368-384, respectively hepatocytes. Although there have been previous reports describing cell surface expression (Tsuboi et al 1994;Hirai et al 1998;Fishelson et al 2001), little is known regarding the orientation of Hsc70 in the plasma membrane or how this well-described cytoplasmic protein localizes to the cell surface. Previously, Hirai et al (1998) identified a monoclonal antibody that recognized an epitope spanning amino acid residues 350-372 of the Hsc70 ATPase domain and confirmed by FACS analysis that this reactive epitope was expressed on the surface of Daudi cells.…”

“…Although prior observations demonstrating cell surface localization of Hsc70 have been reported (Tsuboi et al 1994;Hirai et al 1998;Fishelson et al 2001), little is known regarding the orientation of the protein at the cell surface. Furthermore, the morphogenic changes induced in situ by MAb OC.10 ( Fig.…”

Antibodies to heat-shock protein 27 are associated with improved survival in patients with breast cancer

“…Thus, hsp70 and hsp90 have been located on cell surfaces of tumour cells and tumour cell lines (Konno et al, 1989;Ferrarini et al, 1992;Tsuboi et al, 1994;Multhoff et al, 1995) as well as on the surface of peripheral blood cells in SLE patients (Erkeller-Yuksel et al, 1993). Similarly, Jameel et al (1992) originally identified the altered expression of hsp90 in breast cancer on the basis of its isolation with an antibody prepared to breast membrane preparations, again suggesting the appearance of this protein on the cell surface.…”

T‐Cell Receptor Variable γ Chain Gene Expression in the Interaction between Rat γδ‐Type T Cells and Heat‐Shock Protein 70‐Like Molecule

“…On day 8, the expanded V65(ϩ) lymphocytes were fused with mouse BW5147 TCRαβ(−) cell line and seeded in 96-microwell-plates with HAT (SIGMA, St. Louis, Mo., U.S.A.) medium. The protocol of hybridization between cells was described earlier (8,25). Briefly, approximately 2ϫ10 8 lymphocytes were fused with 4ϫ10 7 BW5147 cells by polyethyleneglycol 4000.…”