TY - JOUR
T1 - Characteristics of CR3-mediated aggregation in human eosinophils
T2 - Effect of priming by platelet-activating factor
AU - Koenderman, Leo
AU - Kuijpers, Taco W.
AU - Blom, Michela
AU - Tool, Anton T J
AU - Roos, Dirk
AU - Verhoeven, Arthur J.
PY - 1991/1/1
Y1 - 1991/1/1
N2 - We have used double-color fluorescence-activated cell sorter analysis to characterize the homotypic aggregation response of human eosinophils (EOs). With this method, we demonstrate for the first time that EOs are able to form stable aggregates. The aggregation response induced by the phorbol ester, phorbol myristate acetate (PMA), was low and was not primed by platelet-activating factor (PAF). In contrast, the aggregation response induced by opsonized particles was markedly enhanced after priming with PAF. Additional experiments with several blocking monoclonal antibodies indicate that the CR3 receptor present on human EOs mediates the homotypic aggregation induced by PMA and by small opsonized particles through a putative "cell-adhesion" site on CR3, which binds to its counter structure on the opposing cell. The signal that initiates this binding event is generated after PMA addition or activation of the iC3b-binding site and is not sensitive for priming by PAF. The priming by PAF of the aggregation response induced by opsonized particles is restricted to an action on the iC3b-binding site, possibly by enhancing the affinity for its ligand.
AB - We have used double-color fluorescence-activated cell sorter analysis to characterize the homotypic aggregation response of human eosinophils (EOs). With this method, we demonstrate for the first time that EOs are able to form stable aggregates. The aggregation response induced by the phorbol ester, phorbol myristate acetate (PMA), was low and was not primed by platelet-activating factor (PAF). In contrast, the aggregation response induced by opsonized particles was markedly enhanced after priming with PAF. Additional experiments with several blocking monoclonal antibodies indicate that the CR3 receptor present on human EOs mediates the homotypic aggregation induced by PMA and by small opsonized particles through a putative "cell-adhesion" site on CR3, which binds to its counter structure on the opposing cell. The signal that initiates this binding event is generated after PMA addition or activation of the iC3b-binding site and is not sensitive for priming by PAF. The priming by PAF of the aggregation response induced by opsonized particles is restricted to an action on the iC3b-binding site, possibly by enhancing the affinity for its ligand.
UR - http://www.scopus.com/inward/record.url?scp=0025776413&partnerID=8YFLogxK
U2 - 10.1016/0091-6749(91)90416-L
DO - 10.1016/0091-6749(91)90416-L
M3 - Article
C2 - 1673978
AN - SCOPUS:0025776413
SN - 0091-6749
VL - 87
SP - 947
EP - 954
JO - The Journal of Allergy and Clinical Immunology
JF - The Journal of Allergy and Clinical Immunology
IS - 5
ER -