As. Trevani et al., ACTIVATION OF HUMAN NEUTROPHILS INDUCED BY IMMUNE-COMPLEXES PREPARED WITH CATIONIC AND ANIONIC FRACTIONS OF NORMAL IGG ANTIBODIES, Scandinavian journal of immunology, 43(3), 1996, pp. 341-344
The authors have recently shown that the ability of immune complexes (
IC) to trigger Fc gamma R-dependent cell responses can be dramatically
enhanced when the isoelectric point (pI) of normal IgG antibodies is
increased from 5.8-8.5 to 8.5-9.8 by treatment with 1-ethyl-3-2(3-dime
thylaminopropyl) carbodiimide HCl and ethylene diamine. In the current
work the authors analyse whether differences in the charge of normal
IgG antibodies map also affect IC activity. Soluble IC (sIC) were prep
ared with (a) rabbit IgG antibodies to human IgG and anionic or cation
ic fractions of human IgG; and (b) bovine serum albumin (BSA) and anio
nic or cationic fractions of rabbit IgG anti-BSA antibodies. Similar a
bilities to bind to neutrophil surface were observed for sIC prepared
with both anionic (anIC) and cationic fractions of IgG (catIC). Moreov
er, no differences were found when neutrophil shape change, chemilumin
escence (CL) emission and elastase release were induced by either anIC
or catIC. As in the case of sIC, particulate IC prepared with erythro
cytes (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 o
f normal IgG antibodies do not affect the ability of IC to trigger neu
trophil responses mediated by receptors for the Fc portion of IgG anti
bodies (Fc gamma R).