Heat shock proteins Hsp 60 and Hsp70 expression in LBC lymphoma cells

HERSCHLIK L; GRAVISACO MJ; DI SCIULLO P; WADNER CI; MONGINI C

Viña del Mar, Chile

Congreso; Immunochile 2009 (IX Congreso Latinoamericano de Inmunología); 2009

Asociación Latinoamericana de Inmunología (ALAI)

Heat shock proteins, have been implicated in loading immunogenic peptides onto MHC molecules for presentation to T-cells and also can act as tumor vaccines. The objective was to determine the expression of the heat shock proteins, Hsp 70 and 60 in LBC T-cell lymphoma cells. By Western Blot we demonstrated the presence of Hsp 70 and Hsp 60. Using flow cytometry we found that 100% LBC cells expressed Hsp 70, and Hsp 60 intracytoplamatically, but it was not possible to detect neither Hsp 70 nor Hsp 60 on LBC cell surface. Interestingly, we found two subpopulations of LBC cells expressing different levels of Hsp60: roughly 80% of LBC cells displayed low levels of Hsp 60 (G mean: 17) and 20% a medium-low level (G mean 68). Subsequent to heat stress (42°C for 1h followed by a 24-h recovery period) the percentage of these subpopulations remained unchanged but an induction in Hsp 60 expression was observed in the small population (G mean:68 vs G mean 112). The level of Hsp 70 did not vary through either control or heated conditions. These results demonstrated the presence of an inducible Hsp60 LBC subpopulation that could be used to improve the anti-tumor immune response.