Particular Features of Immune Response after Invasion of Different Species of Human Demodex Mites.

The purpose of the present study was to find peculiarities of the immune response to the invasion of Demodex folliculorum and Demodex brevis mites. Sixty-six patients with human demodicosis were included in this study. The Demodex mites' density was more than 5 per 1 cm(2). The immune response was evaluated by the identification of membrane markers of the different immune cells by monoclonal antibodies. A significant decrease of the percentage of various parameters was found: the decrease for CD5(+) cells was in 1.4, for CD3(+) in 1.7, for CD4(+) in 1.5, for CD8(+) in 1.5, for CD25(+) in 1.3, for CD71(+) in 1.5, for CD20(+) in 1.2, for IgM in 1.2 and for IgG in 1.1 times. On the other hand, some parameters appeared to be elevated: for CD25(+) B cells in 1.5, for IgA in 1.9 and for circulating immune complexes in 1.4 times in patients with D. brevis infection in comparison with patients with D. folliculorum. The development of two variants of the effector response to the invasion of two different Demodex mites' species was shown: the classic expansion of the humoral reaction with the production of IgM and IgG in the case of D. folliculorum, and the activation of non-specific defense cells in the case of D. brevis. The particular capability of D. brevis to suppress T-cell compartment of immunity was distinctly observed in our comparative study. Thus, there are sharp immune distinctions during an invasion of the two species of human Demodex mites.