Modern concept of physiological signaling systems in cattle fetuses with the participation of FC-γ-receptors

The article presents a literature review on the modification of expression and recycling of Fc-γ-receptors of fetal jejunal enterocytes in cattle. Based on the analyzed data, a modern concept of physiological signaling systems in cattle fetuses with the participation of Fc-γ receptors has been developed. These results indicated age-related modulation of FcγR intestinal cells expression during the entire fetal period of cattle, and the dynamics of changes in the content of polypeptides with different molecular weights that exhibit Fc-γ-binding activity in the basolateral and apical regions of the enterocyte’s plasma membrane and have certain characteristic features for each groups of receptors for IgG. It has been proven that the regulation of FcγR expression by plasma membrane of jejunal enterocytes in cattle during the fetal period of ontogenesis is controlled by mechanisms associated with fetal development. The obtained research results and their in-depth analysis made it possible to propose a scientific concept on the physiological functions of FcγR during the fetal period of cattle ontogenesis. In particular, they translocate signals by the mother-placenta-fetus chain, form one of the key signaling systems for regulating the development of enterocytes, recognize specific signals from immunoglobulins and antigens, play an important role in the transcytosis and recycling of IgG from the amniotic fluid into fetal circulation, and form the immune mechanisms of the fetus for the intrauterine functioning body adaptation and prepare it for antigenic pressure after birth. So, the expression modulation, localization and identification of polypeptides on the plasma membrane that exhibit Fc-γ-binding activity, makes it possible to form a signaling system and control the development of barrier and immune functions in the fetus with the participation of FcγR.