Đang chuẩn bị nút TẢI XUỐNG, xin hãy chờ
Tải xuống
IgG molecules are exposed on a regular basis to acidic conditions during immunoaffinity purification procedures, as well as during the production of some therapeutic immunoglobulin preparations. This exposure is known to induce in them an antigen-binding polyreactivity. The molecular mecha-nisms and the possible biological significance of this phenomenon remain, however, poorly understood. | ỊFEBS Journal Exposure of IgG to an acidic environment results in molecular modifications and in enhanced protective activity in sepsis Iglika K. Djoumerska-Alexieva1 Jordan D. Dimitrov1 2 3 4 Elisaveta N. Voynova1 Sebastien Lacroix-Desmazes2 3 4 Srinivas V. Kaveri2 3 4 and Tchavdar L. Vassilev1 1 Department of Immunology Stefan Angelov Institute of Microbiology Bulgarian Academy of Sciences Sofia Bulgaria 2 Centre de Recherche des Cordeliers Universite Pierre et Marie Curie Paris 6 France 3 Universite Paris Descartes France 4 INSERM U 872 Eq. 16 Paris France Keywords antibodies antibody polyreactivity antigenantibody interaction IgG immunoglobulins Correspondence T. Vassilev Stefan Angelov Institute of Microbiology Bulgarian Academy of Sciences Acad. G. Bonchev St. Block 26 1113 Sofia Bulgaria Fax 359 2 870 0109 Tel 359 2 979 6348 E-mail vassilev@microbio.bas.bg These authors contributed equally to this work Received 22 February 2010 revised 22 April 2010 accepted 18 May 2010 doi 10.1111 j.1742-4658.2010.07714.x IgG molecules are exposed on a regular basis to acidic conditions during immunoaffinity purification procedures as well as during the production of some therapeutic immunoglobulin preparations. This exposure is known to induce in them an antigen-binding polyreactivity. The molecular mechanisms and the possible biological significance of this phenomenon remain however poorly understood. In addition to the previously reported ability of these modified IgG antibodies to interact with a large panel of self-antigens enhanced binding to non-self-antigens bacterial an increased ability to engage in F ab 2 F ab 2 idiotype anti-idiotype interactions and an increased functional antigen-binding affinity are reported here. The newly acquired induced polyreactivity of low-pH buffer-exposed IgG is related to structural changes in the immunoglobulin molecules and is at least partly attributable to the enhanced role of the hydrophobic effect in their interactions with .