Activation of human neutrophils induced by immune complexes prepared with cationic and anionic fraction of normal IgG antibodies.

TREVANI AS, ANDONAEGUI G, KEMPFER C, MALCHIODI EL, GEFFNER JR.

SCANDINAVIAN JOURNAL OF IMMUNOLOGY

Año: 1996 vol. 43 p. 341 - 344

0300-9475

The authors have recently shown that the ability of immune complexes (IC) totrigger Fc gamma R-dependent cell responses can be dramatically enhanced when theisoelectric point (pI) of normal IgG antibodies is increased from 5.8-8.5 to8.5-9.8 by treatment with 1-ethyl-3-2(3-dimethylaminopropyl) carbodiimide HCl andethylene diamine. In the current work the authors analyse whether differences in the charge of normal IgG antibodies may also affect IC activity. Soluble IC (sIC)were prepared with (a) rabbit IgG antibodies to human IgG and anionic or cationicfractions of human IgG; and (b) bovine serum albumin (BSA) and anionic orcationic fractions of rabbit IgG anti-BSA antibodies. Similar abilities to bindto neutrophil surface were observed for sIC prepared with both anionic (anIC) andcationic fractions of IgG (catIC). Moreover, no differences were found whenneutrophil shape change, chemiluminescence (CL) emission and elastase releasewere induced by either anIC or catIC. As in the case of sIC, particulate ICprepared with erythrocytes (E) and anionic or cationic fractions of specific IgG antibodies (IgG-E) showed no differences in their abilities to trigger either CL emission or ADCC. Taken together, these results suggest that the pI of normal IgGantibodies do not affect the ability of IC to trigger neutrophil responsesmediated by receptors for the Fc portion of IgG antibodies (Fc gamma R)