A peptide binding protein having a role in antigen presentation is a member of the HSP70 heat shock family.
A peptide binding protein having a role in antigen presentation is a member of the HSP70 heat shock family.
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在抗原表现中具有作用的肽结合蛋白是HSP70热休克家族的成员。
DOI：
10.1084/jem.170.6.1799
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发表时间：
1989-12-01
影响因子：
15.3
通讯作者：
Pierce, S K
中科院分区：
文献类型：
--
作者：
Vanbuskirk, A;Crump, B L;Margoliash, E;Pierce, S K
T细胞对球状蛋白抗原的识别需要通过表达Ia的APC对抗原进行加工和呈递。加工被认为涉及将抗原摄取到发生蛋白水解的酸性隔室中。所得的含有T细胞抗原决定簇的肽与Ia结合，并在细胞表面呈递给特异性T细胞。抗原肽与Ia结合的机制尚不清楚。我们先前描述了一种72/74 x 10（3）Mr（PBP 72/74）的肽结合蛋白，其在抗原呈递中起作用，如在兔中产生的亲和纯化的PBP 72/74的抗血清阻断细胞色素c向细胞色素c特异性T细胞杂交体呈递的能力所示。在这里，我们表明PBP 72/74被HSP 70蛋白家族成员特异性mAb识别。在蛋白质印迹中，PBP 72/74被mAb 7.10和mAb N27结合，mAb 7.10特异于HSP蛋白的进化保守表位，mAb N27特异于组成型表达和诱导型72/73 × 10（3）Mr HSP 70蛋白。此外，PBP 72/74具有HSP蛋白的第二个共同特征，即与ATP结合。事实上，ATP导致PBP 72/74从与细胞色素c的肽片段（Pc 81-104）的结合中释放，并且PBP 72/74可以通过Pc 81-104从ATP柱洗脱。最后，通过免疫荧光染色显示PBP 72/74的一部分存在于B细胞表面。因此，似乎热休克蛋白的特征被在抗原呈递中起作用的蛋白质共享，表明功能上的一些共性。
The T cell recognition of globular protein antigens requires the processing and presentation of the antigen by Ia-expressing APCs. Processing is believed to involve the uptake of antigen into an acidic compartment where proteolysis occurs. The resulting peptides containing the T cell antigenic determinant are associated with Ia and presented at the cell surface to the specific T cells. The mechanisms by which antigenic peptides become associated with Ia is not known. We previously described a peptide binding protein of 72/74 x 10(3) Mr (PBP72/74) that plays a role in antigen presentation as shown by the ability of an antiserum raised in rabbits to affinity-purified PBP72/74 to block presentation of cytochrome c to a cytochrome c-specific T cell hybrid. Here we show that PBP72/74 is recognized by mAbs specific for members of the HSP70 family of proteins. In Western blots PBP72/74 is bound by mAb 7.10, specific for an evolutionarily conserved epitope of HSP proteins and by mAb N27, specific for both the constitutively expressed and inducible 72/73 x 10(3) Mr HSP70 proteins. In addition, PBP72/74 shares a second common feature of the HSP proteins, that of binding to ATP. Indeed, ATP causes the release of PBP72/74 from binding to a peptide fragment of cytochrome c (Pc 81-104) and PBP72/74 can be eluted from ATP columns by Pc 81-104. Finally, a portion of PBP72/74 is shown to be present on B cell surfaces by immunofluorescence staining. Thus, it appears that characteristics of the heat shock proteins are shared by a protein playing a role in antigen presentation, suggesting some commonality in function.