The effect of microgravity on mast cells as a multifunctional element of the immune system

Abstract

The presented literature review is devoted to the problem of the influence of one of the space flight factors – microgravity on various elements of the immune system, in particular, mast cells (MCs). MCs are one of the parts of innate immunity. They are located in tissues almost everywhere, mainly in close proximity to blood vessels and nerves. Their numbers predominate in organs and tissues located on the border with the external environment. MCs are among the first to interact with invading pathogens. Activation of MCs leads to the release of a wide range of biologically active substances, such as heparin, histamine, chymase, tryptase, leukotrienes LTB4, LTD4, PDG2 and PAF, cytokines IL-10, IL-8, IL-5, IL-3, IL-1 , GM-CSF, TGF-β, VEGF and tumor necrosis factor TNF-α. MCs contribute to the development of allergies, cardiovascular and oncological pathologies, diseases of the respiratory system, and gastrointestinal tract. Numerous factors of spaceflight, such as microgravity, have a negative impact on the immune system. This effect affects the entire development process of immune cells (macrophages, monocytes, neutrophils, T and B lymphocytes, dendritic cells and NK cells), including their proliferation, differentiation, activation, and metabolism. Data is provided that the effect of microgravity on MCs manifests in increased apoptosis, decreased proliferation, as well as disruption of degranulation and secretion of cytokines. Morphofunctional changes in immune cells, including MCs, under microgravity conditions correlate with changes that occur in other mammalian cells and include the induction of apoptosis, changes in the cytoskeleton, disturbances in signaling pathways, cell differentiation, growth, proliferation, migration and adhesion.