کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
2832251 | 1163832 | 2007 | 10 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Strategy for affinity maturation of an antibody with high evolvability to (4-hydroxy-3-nitrophenyl) acetyl hapten Strategy for affinity maturation of an antibody with high evolvability to (4-hydroxy-3-nitrophenyl) acetyl hapten](/preview/png/2832251.png)
In order to quantitate the contribution of amino acid replacements to an increase in affinity during affinity maturation, we measured thermodynamic parameters of the antigen–antibody interaction for a group of anti-(4-hydroxy-3-nitrophenyl) acetyl monoclonal antibodies whose differences in amino acid sequences had arisen only from somatic hypermutation. We prepared a common ancestor and hypothetical intermediate clones that might occur on the affinity maturation pathway, by employing site-directed mutagenesis. Isothermal calorimetric titration of the antigen–antibody reaction revealed that antibody evolution proceeds in two steps. The first step is driven by a decrease in enthalpy, in which two amino acid replacements in the VL region play an essential role. Further accumulation of amino acid replacements in VH and VL regions during the second step induce a progressive increase in affinity, which is driven by an increase in entropy, which has a cooperative mutational effect.
Journal: Molecular Immunology - Volume 44, Issue 9, March 2007, Pages 2436–2445