TY - JOUR ID - 16903 TI - Production and Characterization of Murine Monoclonal Antibodies Recognizing Conformational and Linear Epitopes Localized on Human IgA2 Molecules JO - Iranian Journal of Immunology JA - IJI LA - en SN - 1735-1383 AU - Hajighasemi, Fatemeh AU - Gharagozlou, Soheila AU - Moheghi, Nasrin AU - Ghods, Roya AU - Khoshnoodi, Jalal AU - Shokri, Fazel AD - Department of Immunology, School of Public Health, Tehran University of Medical Sciences AD - Department of Immunology, School of Public Health, Tehran University of Medical Sciences AD - Monoclonal Antibody Research Center, Avesina Research Center, Tehran, Iran Y1 - 2005 PY - 2005 VL - 2 IS - 3 SP - 125 EP - 133 KW - Monoclonal antibody KW - Human IgA2 KW - Conformational Epitope KW - Linear Epitope KW - Immunoblotting KW - ELISA DO - N2 - Background: There are two subclasses of human IgA (IgA1 and IgA2) that differ in antigenic properties and in chemical composition. The constant domains of α1 and α2 heavy chains have >95% sequence homology though major structural differences exist in the hinge region. Quantitation of IgA subclass levels depends on the availability of monoclonal antibodies (MAbs) specific for conserved conformational or linear epitopes restricted to each subclass. Objective: To produce, select and characterize monoclonal antibodies specific for human IgA2. Methods: Splenocytes from BALB/C mice immunized with a human IgA2 myeloma protein were fused with SP2/0 myeloma cells. Fused cells were grown in hypoxanthine, aminopterine and thymidine (HAT) selective medium and cloned by limiting dilution assay. Antibody (Ab) secreting cells were screened by enzyme-linked immunosorbent assay (ELISA) and the specificity of secreted MAbs was further analyzed, using a panel of purified myeloma proteins and some animal sera by ELISA and immunoblotting. The affinity constant (Kaff) was also determined by ELISA. Results: Four murine hybridoma clones designated 2F20G5, 2F20B5, 3F20E3 and 6F20H11 were obtained that secreted MAbs specific for the human IgA2. 2F20G5 and 6F20H11 MAbs react with linear epitope(s) while 2F20B5 and 3F20E3 react with conformational epitope(s) located to human IgA2 subclass. 2F20G5 MAb displays a weak cross-reactivity with monkey and rabbit sera and a strong cross-reactivity with cat and dog sera while the other three MAbs showed no cross-reactivity with the animal sera tested. Conclusion: These MAbs, especially 6F20H11 with high affinity constant (6.03 ×109 M-1) are useful tools for quantitation of human IgA2 subclass levels in various diseases. Cross-reactivity of 2F20G5 MAb with some animalsera suggests phylogenic conservation ofthe epitope recognized by this MAb. UR - https://iji.sums.ac.ir/article_16903.html L1 - https://iji.sums.ac.ir/article_16903_0e9c08260bce7a8ee14ad0bec7830f44.pdf ER -