A novel monoclonal antibody recognizing a cation-dependent epitope within the regulatory loop of human beta(1) integrin (CD29).
A novel monoclonal antibody recognizing a cation-dependent epitope within the regulatory loop of human beta(1) integrin (CD29).
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一种新型单克隆抗体，可识别人 β(1) 整合素 (CD29) 调节环内的阳离子依赖性表位。
DOI：
10.1089/153685902760213868
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发表时间：
2002
期刊：
影响因子：
--
通讯作者：
Simmons,PaulJ
中科院分区：
文献类型：
--
作者：
Lévesque,Jean-Pierre;Takada,Yoshikazu;Puzon-McLaughlin,Wilma;Simmons,PaulJ
Cell adhesion receptors of the integrin superfamily can be expressed in different affinity states towards their ligands. It has been previously demonstrated thatβ1integrinsα4β1andα5β1are expressed in a nonligand binding form by human hemopoietic progenitor cells but can be activated into a ligand binding form by a variety of stimuli including intracellular stimuli generated by cytokine receptors and extracellular stimuli generated by function-activating anti-β1integrin monoclonal antibodies (MAbs). In both instances, the activation ofβ1integrins is believed to be the result of conformational changes propagating along theβ1integrin chain which in turn increase accessibility to the ligand. A cluster of either function-activating or function-inhibiting anti-β1integrin MAbs have been shown to bind within a 12 amino acid long regulatory loop between residues 207 and 218 of the humanβ1integrin chain. We describe in this report the first MAb (96.9H9) specific for this regulatory loop whose binding is cation-dependent and requires either Ca2+or Mn2+but not Mg2+. In addition, the activation ofα4β1andα5β1integrins by 96.9H9 is a two-step process with distinct cation requirements. Whereas Ca2+is sufficient to promote binding of the antibody to theβ1integrin chain, Mg2+is necessary for activating function following 96.9H9 binding. Our data therefore suggest that the regulatory epitope of the humanβ1integrin chain is flexible with multiple conformations according to the cationic environment.
