CD27 expression discriminates porcine T helper cells with functionally distinct properties

Abstract

Differentiation of porcine T helper cells is still poorly investigated, partly due to a lack of monoclonal antibodies (mAbs) specific for molecules involved in this process. Recently, we identified a mAb specific for porcine CD27 and showed that CD27 is expressed by all naïve CD8α- T helper cells but divides CD8α+ T helper cells into a CD27+ and a CD27- subset. In the present study, detailed phenotypical and functional analyses of these T-helper cell subpopulations were performed. Naïve CD8α-CD27+ T helper cells predominantly resided in various lymph nodes, whereas higher proportions of CD8α+CD27+ and CD8α+CD27- T helper cells were found in blood, spleen and liver. Both CD8α+CD27+ and CD8α+CD27- T helper cells were capable of producing IFN-γ upon in vitro polyclonal stimulation and antigen-specific restimulation. Experiments with sorted CD8α-CD27+, CD8α+CD27+ and CD8α+CD27- T-helper cell subsets following polyclonal stimulation revealed the lowest proliferative response but the highest ability for IFN-γ and TNF-α production in the CD8α+CD27- subset. Therefore, these cells resembled terminally differentiated effector memory cells as described in human. This was supported by analyses of CCR7 and CD62L expression. CD8α+CD27- T helper cells were mostly CCR7- and had considerably reduced CD62L mRNA levels. In contrast, expression of both homing-receptors was increased on CD8α+CD27+ T helper cells, which also had a proliferation rate similar to naïve CD8α-CD27+ T helper cells and showed intermediate levels of cytokine production. Therefore, similar to human, CD8α+CD27+ T helper cells displayed a phenotype and functional properties of central memory cells.

Carbopol improves the early cellular immune responses induced by the modified-life vaccine Ingelvac PRRS® MLV

“…By extrapolation it has been suggested, although not formally proven, that these features would endow carbopol with adjuvant properties by exerting an antigen depot effect for single shot vaccines (Lai et al, 2012). Should this be the case, it would provide arguments to support the differentiation to effector cells observed in our study (Reutner et al, 2013). Indeed, a persistent antigenic stimulation is known to induce a preferential switch to effector over memory T cell differentiation (Lanzavecchia and Sallusto, 2005).…”

Intraepithelial T cells diverge by intestinal location as pigs age

“…CD3e was used to identify T cells, and further characterization of total T cells by expression of cell surface markers γδTCR, CD2, CD4, CD8α, and CD27 was assessed. CD2 and CD8α expression are commonly used to identify functional porcine γδ T cell populations (45, 46); CD4 and CD8α expression identify functional porcine αβ T cell populations (47,48); and CD27 expression is indicative of T cell activation and memory states (49)(50)(51)(52). In total, this gating strategy yielded 16 discrete, nonoverlapping IET subpopulations based on CD27 +/expression within each of the 8 defined IET populations ( Fig.…”

Guidelines for the use of flow cytometry and cell sorting in immunological studies (second edition)

“…Porcine CD marker expression as compared to humans and mice include several peculiarities such as The expression of CD8αα homodimers and MHC‐II (swine leukocyte antigen‐DR) molecules on activated or memory CD4 T cells , Major subsets of NK cells that lack CD335 (NKp46) , Expression of CD33 on neutrophils and monocytes , Varying levels of CD45RA expression on plasmacytoid DCs (pDCs) Siglec‐10 expression on B cells . The high abundance of peripheral γδ T cells, ranging from ∼8 to 57% within total peripheral blood lymphocytes (PBL) . …”