Optimization of HSP-70 and Gp96 Production by Prostate and Erythroleukemia Cell Lines: Implication for Cancer Vaccine Preparation

Document Type : Original Article (s)

Authors

1 Department of Cellular and Molecular Biotechnology, Institute of Biotechnology, Urmia University, Urmia, Iran

2 Department of Microbiology, School of Veterinary Medicine, Urmia University, Urmia, Iran

Abstract

Background: Heat shock proteins (HSPs) are a large family of proteins with different molecular weights and differ­ent intracellular localizations. These proteins such as Hsp70 and gp96 have a critical role in presentation of major histocompatibility complex class I (MHC-I)-restricted antigens and induction of CD8+ T cells (TCD8+) responses. These surprising immunological characteristics of HSPs are now the basis for a number of clinical trials for cancer vaccination. We studied two tumor cell lines, i.e. erythroleukemia (K562) and human prostatic carcinoma (LNcap), in order to determine the best temperature that induces the optimized HSP induction. Methods: Each cell line was heated at 3 different temperatures (41, 42, and 43ºC) for 1 hour and then incubated at 37ºC for 3, 6, and 12 hours. HSP70 production and gp96 expression were determined through flow cytometry using a commercially available enzyme-linked immunosorbent assay (ELISA) kit and monoclonal anti gp96, respectively. Findings: Our results showed that the optimum temperature and incubation time for HSP70 and gp96 induction in K562 and LNcap were 43ºC for 3 hours and 43ºC for 12 hours, respectively. Conclusion: Our results revealed that the temperature and post-heating incubation period need to be optimized for each tumor cell line before using in HSP-based tumor vaccine. Keywords: Heat shock protein 70, Gp96, Cancer, Prostate, Erythroleukemia