Association between Serum Heat Shock Proteins and Gamma-Delta T Cells-An Outdated Clue or a New Direction in Searching for an Anticancer Strategy? A Short Report

HSPs demonstrate a strong association with gamma-delta (gamma delta) T cells. Most of the studies regarding interactions between the parameters were conducted in the 1990s. Despite promising results, the concept of targeting gamma delta T cells by HSPs seems to be a forgotten direction due to potent non-peptidic phosphoantigens rather than HSPs have been found to be the essential stimulatory components for human gamma delta cells. Currently, with greater knowledge of lymphocyte diversity, and more accurate diagnostic methods, we decided to study the correlation once again in the neoplastic condition. Twenty-one children with newly diagnosed acute lymphoblastic leukaemia (ALL) were enrolled on the study. Serum HSP90 concentrations were evaluated by an enzyme-linked immunosorbent assay (ELISA), subsets of gamma delta T cells (CD3+ gamma delta, CD3+ gamma delta HLA/DR+, CD4+ gamma delta and CD8+ gamma delta) by flow cytometry. We have shown statistically relevant correlations between serum HSP90 and CD3+ HLA/DR+ gamma delta T cells in paediatric ALL at diagnosis (R = 0.53, p < 0.05), but not after induction chemotherapy. We also have demonstrated decreased levels of both serum HSP90 and CD3+ HLA/DR+ gamma delta T cells before treatment, which may indirectly indicate dose-dependent unknown interaction between the parameters. The results of our study may be a good introduction to research on the association between HSPs and CD3+ HLA/DR+ gamma delta T cells, which could be an interesting direction for the development of anti-cancer strategies, not just for childhood ALL.