Anti Hsp70 Antibodies in Untreated Patients with Chronic Lymphocytic Leukaemia

Background: Chronic lymphocytic leukaemia (CLL) is one of the diseases in which processes of proliferation and apoptosis are altered. It has been intensely studied in the recent years in order to understand the mechanisms of neoplastic development. Hsps or heat shock proteins are molecular chaperones involved in a number of cellular functions in stress conditions. Feng et al. (2002) have reported that heat-stressed apoptotic 12B1-D1 leukaemia cells (BCR-ABL(+)) express Hsp70 on their surface. It has also been suggested that an increased surface expression of heat shock proteins on apoptotic tumour cells results in the generation of potent antitumour T-cell responses. Furthermore, different hsps including Hsp70 have been discovered in indolent lymphoma cells. Anti Hsp70 antibodies are known to play a role in immunological and neoplastic processes. It has been well documented that this antibodies level tends to increase with age likewise an incidence of CLL. However their significance in CLL has not been clearly understood.

Aims: The aim of our study was the assessment of the anti Hsp70 antibody concentration in the patients with CLL.

Material and methods: We assessed 60 peripheral blood samples from the patients with newly diagnosed CLL. (aged 40–77), including 31 males and 29 females. A group of 20 healthy age matched subjects were used as a control group. The patients were in A-C stages of CLL according to Binet scale. Quantitative determination of anti-human Hsp70 antibodies in the serum was done using commercial test (anti Hsp70 Elisa Kits, Stressgen). The results are presented as mean ± SEM. Statistical analysis was done using Shapiro-Wilk, Mann-Whitney and Spearman’s tests.

Results: The levels of anti Hsp70 antibodies were significantly lower in the group of patients with CLL in comparison to healthy controls (105,70±16,86 ng/ml vs.243,71±60,36 ng/ml; p=0,0027). In our analysis there was no association between the levels of antibodies and the stage of the disease. There were no statistically significant correlations between the levels of anti Hsp antibodies and other parameters such as age, gender and some prognostic factors (LDH, β2-microglobulin, and lymphocyte doubling time) in the studied group.

Conclusions: The significantly lower concentrations of anti Hsp70 antibodies in CLL patients suggest that these molecules may play a role in the biology of the disease. Our study revealed lack of correlation between the level of antibodies and the disease prognostic factors. However, further studies utilizing new discovered factors are required to elucidate the role of these proteins in leukaemic biology. The encouraging results from our study suggest that it might be interesting to assess their level in CLL patient after chemotherapy.