title: CH2 and CH3 domain deleted IgG1 paraproteins inhibit differently Fc receptor mediated binding and cytolysis.
abstract: Domain deleted paraproteins are suitable tools to study the interaction between IgG domains and Fc receptor (FcR) binding sites. The effect of the C gamma 2 or C gamma 3 domain deleted paraproteins was compared on antibody dependent cellular cytotoxicity (ADCC) and on FcR mediated rosette formation. The C gamma 2 domain deleted paraprotein (TIM) had no significant effect on lymphocyte or monocyte mediated ADCC, while the C gamma 3 domain deleted paraprotein (SIZ) inhibited both types of cytotoxicity. FcR dependent rosette formation was also inhibited by SIZ but TIM was ineffective. The data further confirm our previous results suggesting a significant role of C gamma 2 domain in the transfer of killing signal in ADCC and that of C gamma 3 domain in the high affinity binding to lymphocyte FcR.
mesh_terms: D000920:Antibody-Dependent Cell Cytotoxicity; D001665:Binding Sites; D006801:Humans; D007128:Immunoglobulin Fragments / Q000276:immunology; D007074:Immunoglobulin G / Q000276:immunology*; D066298:In Vitro Techniques; D008214:Lymphocytes / Q000276:immunology; D009000:Monocytes / Q000276:immunology; D010266:Paraproteins / Q000276:immunology*; D011961:Receptors, Fc / Q000276:immunology*; D012397:Rosette Formation
chemical_list: D007128:Immunoglobulin Fragments; D007074:Immunoglobulin G; D010266:Paraproteins; D011961:Receptors, Fc