Influence of FcγRIIIb polymorphism on its ability to cooperate with FcγRIIa and CR3 in mediating the oxidative burst of human neutrophils.
Considering that human neutrophil FcγRIIa and FcγRIIIb receptors interact synergistically with CR3 in triggering neutrophil functional responses, allelic polymorphisms in these receptors might influence such interactions. We assessed whether FcγRIIIb polymorphisms affect FcγR/CR cooperation in mediating the neutrophil oxidative burst (OB), in particular the FcγRIIIb/CR3 cooperation that occurs via lectin-saccharide-like interactions. The OB of human neutrophil antigen (HNA)-1a-, HNA-1b-, and HNA-1a/-1b-neutrophils stimulated with immune complexes, opsonized or not with serum complement, was measured by the luminol-enhanced chemiluminescence assay. Compared with HNA-1a-neutrophils, HNA-1b-neutrophils exhibited reduced FcγR-stimulated OB, but increased FcγR/CR-stimulated OB. It suggests that (i) FcγR and CR cooperate more effectively in HNA-1b-neutrophils, and (ii) the HNA-1b allotype influences the FcγRIIIb cooperation with FcγRIIa, but not with CR3. HNA-1a- and HNA-1b-neutrophils exhibited similar OB responses elicited via CR3 alone or via FcγR/CR-independent pathways. In addition, the level of FcγRIIIb, FcγRIIa, and CR3 expression did not differ significantly among the neutrophil groups studied. Together, these results demonstrate that the HNA-1b allotype influences the functional cooperation between FcγRIIIb and FcγRIIa, and suggest that the difference in the glycosylation pattern between HNA-1a and HNA-1b does not affect the FcγRIIIb cooperation with CR3.
['Urbaczek|Ana Carolina|AC|', 'Toller-Kawahisa|Juliana Escher|JE|', 'Fonseca|Luiz Marcos|LM|', 'Costa|Paulo Inácio|PI|', 'Faria|Carolina Maria Quinello Gomes|CM|', 'Azzolini|Ana Elisa Caleiro Seixas|AE|', 'Lucisano-Valim|Yara Maria|YM|', 'Marzocchi-Machado|Cleni Mara|CM|']
D000328:Adult D000936:Antigen-Antibody Complex D003165:Complement System Proteins D005260:Female D058851:GPI-Linked Proteins D005786:Gene Expression Regulation D006239:Haplotypes D006801:Humans D007519:Isoantigens D016177:Macrophage-1 Antigen D008297:Male D009504:Neutrophils D011110:Polymorphism, Genetic D061251:Primary Cell Culture D020239:Receptor Cross-Talk D017452:Receptors, IgG D016897:Respiratory Burst D015398:Signal Transduction
Polymorphism Oxidative burst Neutrophil Complement receptor Fcγ receptor