CD4, also known as L3T4, T4, and W3/25, is an approximately 55 kDa type I transmembrane glycoprotein that is expressed predominantly on thymocytes and a subset of mature T lymphocytes. It is a standard phenotype marker for the identification of T cell populations. Mature human CD4 consists of a 371 aa extracellular region containing four immunoglobulin-like domains, a 22 aa transmembrane segment, and a 40 aa cytoplasmic domain. Within the ECD, human CD4 shares approximately 52% aa sequence identity with mouse and rat CD4. CD4 is expressed along with CD8 on double positive T cells during their development in the thymus. Either CD4 or CD8 expression is then lost, giving rise to single positive (SP) CD4+ or CD8+ mature T cells. CD4+ SP cells, also known as T helper cells, further differentiate into multiple subsets of CD4+ cells including Th1, Th2, Th17, Tfh, and Treg cells which regulate humoral and cellular immunity. CD4 is reexpressed on circulating CD8+ T cells upon activation and contributes to their cytotoxic effector activity. In human, CD4 is additionally expressed on macrophages, neutrophils, monocytes, NK cells, and neurons and glial cells in the brain. Similar CD4 distribution between species cannot be assumed as demonstrated by its presence on macrophages in human and rat but not in mouse. CD4 binds directly to MHC class II molecules on antigen presenting cells. This interaction contributes to the formation of the immunological synapse which is focused around the TCR-MHC class II-antigenic peptide interaction.

 

产品性质

别名	CD4 antigen (p55); CD4 molecule; CD4 receptor; CD4; CD4mut; EU3
Uniprot No.	P01730
表达区间及表达系统	Recombinant Human CD4/LEU3 Protein is expressed from HEK293 Cells with His tag and Avi tag at the C-terminal. It contains Lys26-Trp390.
分子量	Approximately 43.6 kDa. Due to glycosylation, the protein migrates to 50-60 kDa based on Tris-Bis PAGE result.
纯度	> 95% as determined by SDS-PAGE and HPLC.
活性	ELISA Data: Immobilized Human CD4 at 0.5μg/ml (100μl/Well) on the plate. Dose response curve for Anti-CD4 Antibody, hFc Tag with the EC50 10.6ng/ml determined by ELISA.
内毒素	< 1.0 EU per 1μg of the protein by the LAL method.
制剂	Lyophilized from 0.22 μm filtered solution in PBS (pH 7.4). Normally 5% trehalose is added as protectant before lyophilization.
复溶	Centrifuge tubes before opening. Reconstituting to a concentration more than 100 μg/mL is recommended (usually we use 1 mg/mL solution for lyophilization). Dissolve the lyophilized protein in distilled water.

 

运输与保存方法

 

冰袋运输。-20℃至-80℃保存，一年有效期。

复溶后，-20 至 -80°C，在未开封状态下保存 3-6 个月。复溶后，2-8°C 保存 2-7 天。

建议第一次使用时分装冻存，避免反复冻融。

 

注意事项

1. 避免反复冻融。

2. 为了您的安全和健康，请穿实验服并戴一次性手套操作。

3. 本产品仅作科研用途！

 

产品数据

HB220809