Mycobacterium bovis BCG and purified protein derivative-induced reduction in the CD80 expression and the antigen up-take function of dendritic cells from patients with cervical cancer

ObjectiveClinical diagnostic studies have reported that co-existence of malignancy and tuberculosis in regions with high incidence of tuberculosis may be possible. However, simultaneous occurrence of cervical cancer (CaCx) and tuberculosis has been reported for it rarity. Our analysis of prevalence of mycobacterial infection among the study group of patients with CaCx had revealed co-infection of mycobacterium species including Mycobacterium tuberculosis. Since M. tuberculosis potentially affects the dendritic cells-mediated protective immune response, the main aim of this study was to analyse the effect of the mycobacterial infection on the immunological functions of dendritic cells (DC) in patients with CaCx.Study designInitially, the prevalence of mycobacterial infection was analysed in the blood samples of patients with CaCx using ELISA and PCR techniques. Later to determine the role of mycobacterial infection on immunosuppression of DC in the progression of CaCx, dendritic cell-mediated immune suppression induced by Mycobacterium bovis BCG (M. bovis BCG) and purified protein derivative (PPD) was studied in patients with CaCx. Expression of co-stimulatory molecules CD80 and CD86, and the antigen processing function of the macrophage-derived immature dendritic cells (imDC) were analysed.ResultsWhen compared to untreated imDC, the PPD and M. bovis BCG-treated imDC displayed 15% and 46.7% reduced expression of CD80, respectively. However, the M. bovis BCG and PPD did not have any significant reduction in the CD86 expression. Moreover, the dextran up-take was reduced by 24.4% and 35.8% with PPD and M. bovis BCG treatment, respectively. In addition, the M. bovis BCG-treated imDC derived from patients with CaCx showed a marginal reduction of lymphocyte proliferation and the PPD-treated imDC did not show a significant stimulation of lymphocyte proliferation.ConclusionThese results indicate that the PPD and M. bovis BCG inhibit the maturation and antigen up-take property of macrophage-derived imDC in patients with cervical cancer, suggesting that the M. tuberculosis infection may favour the progression of cervical cancer through immunosuppressed imDC.