Porcine γ/δ T lymphocyte subsets differing in their propensity to home to lymphoid tissue

Abstract

Three types of T cell receptors (TcR) gamma/delta were identified in swine, all of which are disulfide-bonded cell surface heterodimers. The first, a 38/40-kDa molecule, is related to the TcR gamma/delta of sheep and cattle, and defines in swine a subset of CD4-CD8- T lymphocytes that is enriched in the circulating T lymphocyte pool. The other two receptors are private to swine. The second, a 37/40-kDa molecule, is expressed by the major subset of CD2-CD4-CD8- T lymphocytes that is neither enriched in nor excluded from lymphoid tissue. By contrast, the third type of TcR gamma/delta, a 40/46-kDa molecule, is found on CD2+CD4-CD8- T lymphocytes accumulating in lymphoid tissue. Thus, TcR gamma/delta T lymphocyte subsets differing in homing propensity are typified by the expression of distinct molecular forms of the TcR gamma/delta.

Porcine γδ T Lymphocytes Can Be Categorized into Two Functionally and Developmentally Distinct Subsets according to Expression of CD2 and Level of TCR

“…Porcine TCRgd med and TCRgd hi cells are distributed differently among CD2/CD8 subsets, which are know to home differentially into various lymphatic tissues. Whereas CD2 2 CD8 2 are preferentially TCRgd hi and are enriched in the blood, CD2 + CD8 2 and CD2 + CD8 + are prevalently TCRgd med and accumulate in other tissues (8). Such findings are in accordance with reported findings in cows, where CD8 + and CD8 2 gd T cells also exhibit a defined tissue tropism.…”

“…Moreover, our earlier finding shows that there is a substantial difference between CD2 + and CD2 2 subsets in expression of CD25, CD11b, SWC1, SWC7, MHC-II, and the family of CD45 molecules (12). The conclusion that CD2 + and CD2 2 gd T cell are two lineages is also supported by the finding that they differ in expression of TCRg-chains (8). Furthermore, findings in cows show that these two lineages differ in expression of non-TCRgd cell Ags WC1 and GD3.5, in expression of cell adhesion molecules, and in ability to infiltrate into inflammatory sites (15,23).…”

“…Traditionally, gd T cells in swine are subdivided into three subsets based on their expression of CD2 and CD8 and include CD2 2 CD8 2 , CD2 + CD8 2 , and CD2 + CD8 + cells (3)(4)(5)(6)(7). These individual subsets differ in their homing characteristic (8) and cytotoxic activities (7,9). However, except for the indication that CD8 2 can differentiate into CD8 + gd T cells (10), there is no report showing whether the CD2/CD8 subsets represent separate and independent lineages or whether they represent subsequently developing subsets.…”

Membrane markers of the immune cells in swine: an update

“…Biochemical analysis revealed that one TcR -chain of 40 kDa MW and three distinct TcR -chains of 37, 38 and 46 kDa MW are distributed in different subsets of porcine T cells [92,168,221].…”

“…It is originally the sheep red blood cell receptor [167] and the anti-CD2 mAb block formation of the T-cell rosette [83]. [92,168,239]; in addition, there is a large proportion of non-T (CD3 − ), non-B (sIg-) lymphocytes expressing CD2, (CD2 + CD4 − CD8 low ) and exhibiting a natural killer activity [239], as well as a subset of B lymphocytes albeit with CD2 at low level [196]. In foetus cells with a high level of MHC (major histocompatibility complex) class II and a low level of CD2 and CD25 expression may represent B cell precursors [194,197].…”