Immunophenotype of dendritic cell differentiation markers in breast cancer in in vitro conditions

During maturation, dendritic cells begin to synthesize peptides that are MHC-II co-stimulatory molecules CD40, CD80 and CD86, as well as CD83 proteins. In cancer patients, DC dysfunction can lead to serious consequences in the form of deficiency of antitumor immunity, tumor progression, and decreased response to immunotherapy. All this is important to take into account to rethink the tumor immunotherapy strategy. Thus, approaches aimed at enhancing the viability of DCs and preventing their dysfunction and polarization should be considered as a necessary step in the work to increase the effectiveness of DC-based vaccines. The study is conducted to evaluate the expression characteristics of differentiation markers of dendritic cell maturation obtained from peripheral blood monocytes under culture conditions in patients with breast cancer. With informed voluntary consent, 19 patients diagnosed with breast cancer were examined. Mononuclear cells were isolated on a Ficoll density gradient. For adhesion of monocytes to the bottom of culture flasks with a volume of 75 cm2, they were pre-incubated for 1.5 hours in conditions of 5% CO2 at 37˚C. Growth and differentiation factors – GM-CSF (40 µl) and IL-4 (40 µl) – were added to the attached monocytes, which were added on the 1st, 3rd and 5th days of cultivation. Immunophenotyping of dendritic cells was carried out on days 7 and 9 of cultivation using flow cytometry. Flow cytometry data indicate that the viability of cultured dendritic cells in cancer patients is significantly reduced on day 9 compared to day 7 of culture. On day 9, there was a significant increase (p=0.028) in CD80+ expression (2.40 times) and a decrease in CD83+ (1.65 times) compared to day 7 (p=0.036). In general, significant signs of maturation are observed: loss of the monocyte marker CD14, increased expression of CD80+, CD83+, CD86+ - the main markers. A decrease in CD83+ can be considered as a suppression of excessive activation of immune responses. In the future, a more in-depth study of the characteristics of maturation and activation of cultured dendritic cells is necessary to understand the mechanisms and factors influencing the decrease in the effectiveness of immunotherapy with an autologous dendritic cell vaccine.