Neuroimmune system in the context of "Mast cells"

The gut–brain axis is the two-way biochemical signaling that takes place between the gastrointestinal tract (GI tract) and the central nervous system (CNS). The term "microbiota–gut–brain axis" highlights the putative role of gut microbiota interacting with brain functions, according to preliminary research. Broadly defined, the gut–brain axis includes the central nervous system, neuroendocrine system, neuroimmune systems, the hypothalamic–pituitary–adrenal axis (HPA axis), sympathetic and parasympathetic arms of the autonomic nervous system, the enteric nervous system, vagus nerve, and the gut microbiota.

Chemicals released by the gut microbiome can influence brain development, starting from birth. A review from 2015 states that the gut microbiome influences the CNS by "regulating brain chemistry and influencing neuro-endocrine systems associated with stress response, anxiety and memory function".

A mast cell (also known as a mastocyte or a labrocyte) is a resident cell of connective tissue that contains many granules rich in histamine and heparin. Specifically, it is a type of granulocyte derived from the myeloid stem cell that is a part of the immune and neuroimmune systems. Mast cells were discovered by Friedrich von Recklinghausen and later rediscovered by Paul Ehrlich in 1877. Although best known for their role in allergy and anaphylaxis, mast cells play an important protective role as well, being intimately involved in wound healing, angiogenesis, immune tolerance, defense against pathogens, and vascular permeability in brain tumors.

The mast cell is very similar in both appearance and function to the basophil, a type of white blood cell. Although mast cells were once thought to be tissue-resident basophils, it has been shown that the two cells develop from different hematopoietic lineages and thus cannot be the same cells.