Tissue distribution and biochemical and functional properties of Tp55 (CD27), a novel T cell differentiation antigen.

Abstract

Two monoclonal antibodies (CLB-CD 27/1 and CLB-CD 27/2) were raised against a novel determinant on human T lymphocytes. One of these antibodies, CLB-CD 27/1 (clone 9F4), was grouped by the Third International Workshop and Conference on Human Leucocyte Differentiation Antigens together with three other monoclonal antibodies (VIT 14, OKT 18A, and S152) in the new cluster CD27. In this paper we show that antibodies belonging to this cluster recognize an antigen present on a large subset of peripheral T lymphocytes and most medullary thymocytes. At least two different nonoverlapping epitopes were identified with directly labeled monoclonal antibodies. Immunoprecipitation studies indicate that the target antigen of CD27 antibodies is a polypeptide of 55 kDa, which appears in the form of a disulfide-linked homodimer on the T lymphocyte membrane (Tp55). Stimulation of T cells via the T3/T cell antigen-receptor complex, with either phytohemagglutinin or CD3 monoclonal antibodies, resulted in a fivefold increase in the membrane expression of Tp55, whereas activation by phorbol myristate acetate caused a marked down-regulation. Moreover, an additional molecule of 32 kDa was precipitated from the membrane of activated but not of resting T cells. Addition of CD27 antibodies to cultures stimulated with either phytohemagglutinin or CD3 monoclonal antibody led to enhanced proliferation, whereas no effect was observed in phorbol myristate acetate or interleukin 2-stimulated cultures. The possible role of the Tp55 antigen in T cell activation is discussed.

The CD70-CD27 axis in oncology: the new kids on the block

“…In human thymocyte development, CD27 expression could only be detected on the latest stage [30,31]. Moreover, a few studies showed that human thymic stromal cells that provide essential signals for T cell development and clonal selection express low levels of CD70 [29,32].…”

B cell depletion attenuates CD27 signaling of T helper cells in multiple sclerosis

“… 40 , 41 , 42 , 43 CD27 signaling leads to the induction of pro-survival pathways 44 , 45 and supports the efficient expansion and differentiation of activated T cells. 46 , 47 , 48 , 49 CD27 expression is transiently upregulated upon T cell receptor (TCR) engagement 50 , 51 , 52 and proteolytically cleaved and released as sCD27 upon sustained signaling. 37 , 53 , 54 Surface expression of CD27 therefore naturally declines along the T cell differentiation path, 42 with naive T cells having the highest expression and more differentiated subsets showing a lower expression.…”

Neoadjuvant intratumoral influenza vaccine treatment in patients with proficient mismatch repair colorectal cancer leads to increased tumor infiltration of CD8+ T cells and upregulation of PD-L1: a phase 1/2 clinical trial

“…CD27 is a protein involved at different time points in the differentiation of T cells. 35 The expression is downregulated during differentiation and upregulated in memory T cells, while a persistent upregulation can be seen in FOXP3+Tregs. A reduced CD27 protein expression may thus align with our findings of reduced FOXP3 levels in immune-infiltrated tumor areas.…”