Blood Cells - Tissue Functioning and Remodeling in the Circulatory and Ventilatory Systems - page 98

3.8.1 Mastocyte Origin and Maturation

Mastocytes derive from hematopoietic stem cells and undergo differentiation and
maturation after migration of mastocyte precursors from blood to tissues, especially
those exposed to the environment (skin, conjunctiva membrane of eyes, airways,
and gastrointestinal and genital tract), or serosal cavities (pericardial, peritoneal,
and pleural cavities). 83
Mastocytes derive from multipotent hematopoietic progenitor cells in the bone
marrow and Thy1 low , 84 SCFR high , 85 , 86 , 87 , 88 , 89

CD13 + CD33 + CD34 + CD38 +

bone marrow-derived circulating progenitors and Fc precursors in blood.

These precursors generate mastocytes only in destination tissue (in which they
become resident).
Stem cell factor is required to ensure mastocyte survival in the body's tissues. 90
However, the mature mastocyte type (mucosal and connective tissue mastocytes,
among other types) varies according to growth factor stimuli (interleukins IL3, IL4,
and IL9; transforming growth factor-

RI −

1; etc.) [ 191 ].
Mastocytes are long-lived cells that proliferate upon suitable stimulation. Mas-
tocyte recruitment and local maturation of mastocyte progenitors contribute to the
expansion of mastocyte population. Division and tissue redistribution of mastocytes,
as well as mastocyte type modulation particularly occur during helper-2 T-cell
responses.
Mastocytes can also derive from thymocytes at double-negative stages DN1 and
DN2 (but not at DN3 stage) when transcription factor GATA3 is upregulated, al-
though Gata3 is one of the earliest activated genes when the Notch pathway triggers
T-lineage differentiation from hematopoietic precursors [ 192 ]. DN2 thymocytes can
also bear respecification to the mastocyte lineage in the presence of interleukin-3
and stem cell factor and in the simulataneous absence of Notch signaling.

β

83 Serosa is a membrane made of a thin layer of epithelial cells lying on a thin connective tissue
tunica with capillaries and nerves that excrete serous fluid. In serous cavities, the cells secrete a
lubricating fluid that reduces friction during motion.
84 Thymocyte differentiation plasmalemmal glycoprotein (antigen).
85 Mast and stem cell growth factor receptor.
86 Myeloid plasmalemmal glycoprotein and zinc-binding metallopeptidase, a.k.a. alanyl aminopep-
tidase and aminopeptidase-M (APm) and -N (APn).
87 Myeloid plasmalemmal antigen also called sialic acid-binding Ig-like lectin-3 (siglec-3).
88 Hematopoietic progenitor cell antigen, a L-selectin ligand.
89 Ecto ADP ribosyl cyclase-1.
90 Stem cell factor and interleukin-4 regulate not only the development of mastocytes from myeloid
progenitors, but also the function of mature mastocytes. Stem cell factor promotes mastocyte
proliferation, prevents mastocyte apoptosis, and enhances IgE-dependent mediator and cytokine
release.