Cl. Kepley et al., THE IDENTIFICATION AND CHARACTERIZATION OF UMBILICAL-CORD BLOOD-DERIVED HUMAN BASOPHILS, Journal of leukocyte biology, 64(4), 1998, pp. 474-483
Cross-linking allergen-specific immunoglobin E on human peripheral blo
od basophils results in the release of histamine and other inflammator
y mediators that initiate allergy and asthma. The signaling pathways l
eading from IgE binding to mediator release have not been well establi
shed, mainly due to the difficulty in obtaining adequate numbers of hi
ghly purified basophils, It was the goal of this study to easily obtai
n Fc epsilon RI-positive human basoplrils in high yield and purity for
studies of signal transduction pathways, We describe all in vitro cul
ture system in which pulsing normal human cord blood leukocytes with i
nterleukin-3 (IL-3) for 3-4 h followed by incubation in medium with fe
tal bovine serum generates a cell population that is predominately Fc
epsilon RI positive between 14 and 28 days of culture. These cells res
emble peripheral blood basophils when examined by light and electron m
icroscopy. Like normal blood basophils, they express the integrins, CD
11b, CD18, CD29, and CD49d. A majority of the IL-3-pulsed cells also e
xpress a marker recognized by the basophil-specific antibody, 2D7, Fc
epsilon RI cross-linking results in a time and dose-dependent release
of histamine. Fc epsilon RI cross-linking also stimulates protein-tyro
sine phosphorylation, thought to be the first event leading to the IgE
-mediated activation of peripheral blood basophils, These studies esta
blish cord blood as an accessible source from which basophil-like cell
s call be developed to examine Fc epsilon RI-mediated signal transduct
ion.