IgG-aggregates rapidly upregulate FcgRI expression at the surface of human neutrophils in a FcgRII-dependent fashion: A crucial role for FcgRI in the generation of reactive oxygen species

Article

关键词: FC-GAMMA-RIIA;    HIGH-AFFINITY RECEPTOR;    IMMUNE-COMPLEXES;    DIAGNOSTIC MARKER;    CD64 EXPRESSION;    CROSS-LINKING;    ACTIVATION;    ADENOSINE;    IMPACT;    CYCLOOXYGENASE-2;   

DOI  :  10.1096/fj.202001085R

来源: SCIE

【 摘 要 】

Autoimmune complexes are an important feature of several autoimmune diseases such as lupus, as they contribute to tissue damage through the activation of immune cells. Neutrophils, key players in lupus, interact with immune complexes through Fc gamma receptors (FcgR). Incubation of neutrophils with aggregated-IgGs caused degranulation and increased the surface expression of FcgRI within minutes in a concentration-dependent fashion. After 30 minutes, IgG aggregates (1 mg/mL) upregulated FcgRI by 4.95 +/- 0.45-fold. FcgRI-positive neutrophils reached 67.24% +/- 6.88% on HA-IgGs stimulated neutrophils, from 3.12% +/- 1.62% in non-stimulated cells, ranking IgG-aggregates among the most potent known agonists. FcgRIIa, and possibly FcgRIIIa, appeared to mediate this upregulation. Also, FcgRI-dependent signaling proved necessary for reactive oxygen species (ROS) production in response to IgG-aggregates. Finally, combinations of bacterial materials with aggregates dramatically boosted ROS production. This work suggests FcgRI as an essential component in the response of human neutrophils to immune complexes leading to the production of ROS, which may help explain how neutrophils contribute to tissue damage associated with immune complex-associated diseases, such as lupus.

【 授权许可】

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