Tag Archives: antigen

Avidity of polyreactive immunoglobulins

S. A. Bobrovnik

Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
e-mail: s-bobrov@bk.ru

An analysis of the mechanism of interaction between polyreactive immunoglobulins (PRIG) and antigen was conducted and it was shown that most of the traditional methods of antibody affinity evalua­tion are not applicable for PRIG affinity. The comparative assessment of the mouse and human PRIG avidity against ovalbumin and horse myoglobin and the avidity of specific monoclonal antibodies against ovalbumin have shown that the avidity of PRIG not only is much less than the avidity of monoclonal antibodies but even exceeds it.

Idiotype-antiidiotypic interaction of antibodies in the bloodstream

S. A. Bobrovnik

Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
е-mail: s-bobrov@bk.ru

A problem of “prozone” formation in agglutination of corpuscular antibodies by bivalent antibodies­ was considered. Using a new coordinate system, which was proposed by us earlier, we analyzed theoretical and experimental curves that describe relations between bivalent antibody concentration and some blocking factors. It was shown that occupation of antibody paratopes by a blocking­ factor or by antiidiotypic antibodies can induce “prozone” formation. It was also demonstrated that experimental titration curves for a mixture of antibodies and corresponding antigens coincide with theoretical curves that were calculated according to our theory. Our data also demonstrate that major part of serum antibodies are blocked by antiidiotypic antibodies when maximum of antibody formation is over and antibody titers come down.