Search results for "Delta cell"

γδ T cells as a potential tool in colon cancer immunotherapy

2014

γδ T cells are capable of recognizing tumor cells and exert potent cellular cytotoxicity against a large range of tumors, including colon cancer. However, tumors utilize numerous strategies to escape recognition or killing by patrolling γδ T cells, such a downregulation of NKG2D ligands, MICA/B and ULBPs. Therefore, the combined upregulation of T-cell receptorand NKG2D ligands on tumor cells and induction of NKG2D expression on γδ T cells may greatly enhance tumor killing and unlock the functions of γδ T cells. Here, we briefly review current data on the mechanisms of γδ T-cell recognition and killing of colon cancer cells and propose that γδ T cells may represent a promising target for the…

Cross-talk between Vβ8+and γδ+T lymphocytes in contact sensitivity

1998

We have previously reported that T lymphocytes proliferating in vitro to the hapten trinitrochlorobenzene (TNCB) exhibit a very restricted V beta gene usage and response to TNCB is limited to T-cell receptors (TCR) composed of V beta 8.2 in combination with V alpha 3.2, V alpha 8 and V alpha 10. This paper investigates the role played by T lymphocytes expressing the V beta 8.2 gene segment in the contact sensitivity (CS) reaction to TNCB in the intact mouse and in its passive transfer into naive recipient mice. Mice injected with monoclonal antibodies to V beta 8 are unable to develop CS upon immunization with TNCB and 4-day TNCB-immune lymph node cells from mice that had been depleted in v…

Role of γδ T lymphocytes in immune response in humans and mice

1998

T lymphocytes recognize antigen through the T cell receptor. T cells expressing the gamma delta T cell receptor have been found in many species. Whereas murine alpha beta T cells are concentrated in the lymphoid organs, gamma delta T cells represent only a minor population in the adult thymus and peripheral lymphoid organs (less than 5% of the population). However, murine gamma delta cells predominate in epidermis, in epithelial layers of small intestine, in lung, and in female reproductive organs. In contrast, human gamma delta cells predominate in lymphoid organs. Despite extensive progress in the molecular characterization of the gamma delta T cell receptor and its genes, the physiologic…

An unconventional TRAIL to cancer therapy

2013

Editorial: Activation, functions, and generation of immunological memory in γδ T lymphocytes: lessons from nonhuman primates

2014

T cells constitute an unconventional lymphocyte population with distinct functions complementary to those of CD4 and CD8 T cells. As such, they have both adaptive features, such as expression of the TCR, and innate-like functions reminiscent of NK cells, with whom they share extensive repertoires of activating and inhibitory receptors [1, 2]. Although most antigens recognized by murine T cells remain obscure, advances have been made in identifying ligands for human T cells. The majority of circulating human T lymphocytes expresses a TCR formed by the preferentially-paired V 9 and V 2 chains (here and thereafter, called V 9V 2 T cells). Instead of binding peptides associated with molecules b…

Tumor-Infiltrating γδ T Lymphocytes: Pathogenic Role, Clinical Significance, and Differential Programing in the Tumor Microenvironment.

2014

There is increasing clinical evidence indicating that the immune system may either promote or inhibit tumor progression. Several studies have demonstrated that tumors undergoing remission are largely infiltrated by T lymphocytes [tumor-infiltrating lymphocytes (TILs)], but on the other hand, several studies have shown that tumors may be infiltrated by TILs endowed with suppressive features, suggesting that TILs are rather associated with tumor progression and unfavorable prognosis. γδ T lymphocytes are an important component of TILs that may contribute to tumor immunosurveillance, as also suggested by promising reports from several small phase-I clinical trials. Typically, γδ T lymphocytes …

Control of Gastric Acid Secretion in Somatostatin Receptor 2 Deficient Mice: Shift from Endocrine/Paracrine to Neurocrine Pathways

2007

The gastrin-enterochromaffin-like (ECL) cell-parietal cell axis is known to play an important role in the regulation of gastric acid secretion. Somatostatin, acting on somatostatin receptor type 2 (SSTR2), interferes with this axis by suppressing the activity of the gastrin cells, ECL cells, and parietal cells. Surprisingly, however, freely fed SSTR2 knockout mice seem to display normal circulating gastrin concentration and unchanged acid output. In the present study, we compared the control of acid secretion in these mutant mice with that in wild-type mice. In SSTR2 knockout mice, the number of gastrin cells was unchanged; whereas the numbers of somatostatin cells were reduced in the antru…