T-cell receptor variable gamma chain gene expression in the interaction between rat gammadelta-type T cells and heat-shock protein 70-like molecule

Characterization of human peripheral blood γδ T cells in patients with sepsis

In total, 30 cases of patients undergoing health check-ups with the diagnostic criteria of sepsis were included in the present study. The clinical data of each patient with sepsis were recorded at admission. In the present study, the association between the proportion of T cells in patients with sepsis and those in a healthy condition were observed. The expression of immunosuppressive molecules on the surface of Vδ1 T cells were examined, as well as studying the secretion of inflammatory cytokines in Vδ2 T cells, and the ability of the Vδ1 T cells to inhibit the secretory level of interferon-γ (IFN-γ) and the inflammatory function of Vδ2 T cells were monitored. The inhibition of proliferation of naïve CD4 T cells by Vδ1 T cells and inflammatory function of Vδ2 T cells were examined. The number of Vδ1 T cells in the peripheral blood of patients with sepsis was significantly increased compared with healthy controls (P<0.01); the proportion of Vδ2 T cells was opposite to that of Vδ1 T cells. The Sequential Organ Failure Assessment score, survival and survival time were positively associated with Vδ1 T cell ratio (P<0.05) and negatively correlated with Vδ2 T cells. The expression of cytotoxic T-lymphocyte protein 4 and T cell immunoglobulin and mucin domain-containing protein 3 on the surface of Vδ1 T cells in the peripheral blood of patients with sepsis was significantly increased compared with the healthy controls (P<0.01), and the levels of IFN-γ and tumor necrosis factor-α secreted by Vδ2 T cells were significantly decreased (P<0.01). The immunosuppressive function of Vδ1 T cells was significantly higher, and the function of Vδ2 T cells was significantly reduced (P<0.01). The phosphorylation level of Erk1/2 in Vδ2 T cells was significantly lower (P<0.01). The present results suggested that the imbalance and functional changes of different γδ T cell subtypes in the peripheral blood of patients with sepsis are associated with sepsis, and may be involved in sepsis progression.

A Calcium Binding Protein, S100A4, Mediates T Cell Dependent Cytotoxicity as a Transformation-Associated Antigen

The nature of the target molecule of TCR gamma delta T cell-mediated lysis remains to be determined. As we previously reported, #067 monoclonal antibody (mAb) recognizes one of the transformation-associated antigens, designated as #067 antigen. This antigen is expressed on the cell surface of rat fibrosarcoma W31 cells, which are established by transformation of fetal fibroblastic WFB cells with H-ras oncogene. It has been suggested that the #067 antigen is a target molecule for TCR gamma delta T cells since #067 mAb inhibited TCR gamma delta T cell-mediated lysis against #067 positive cells. In this study we attempted to identify the protein sequence of the #067 antigen. By using molecular cloning techniques, we demonstrated that a calcium binding protein, S100A4, was possibly one and the same molecule as the #067 antigen. It was shown that the expression of S100A4 was higher in W31 cells than in WFB cells at transcription and protein level. Flow cytometry and immunocytochemical studies showed that #067 antigen partially co-localized with S100A4 on the cell surface as well as the cytoplasm of W31 cells. Moreover, rabbit anti-S100A4 polyclonal antibodies (pAb) inhibited TCR gamma delta T cell-mediated lysis against #067 positive cells. Our results indicated that S100A4 may play a role as a possible target molecule for TCR gamma delta T cell-mediated lysis although how S100A4 is involved in TCR gamma delta T cell-mediated lysis remains to be determined.

HSPA8/HSC70 chaperone protein: structure, function, and chemical targeting

HSPA8/HSC70 protein is a fascinating chaperone protein. It represents a constitutively expressed, cognate protein of the HSP70 family, which is central in many cellular processes. In particular, its regulatory role in autophagy is decisive. We focused this review on HSC70 structure-function considerations and based on this, we put a particular emphasis on HSC70 targeting by small molecules and peptides in order to develop intervention strategies that deviate some of HSC70 properties for therapeutic purposes. Generating active biomolecules regulating autophagy via its effect on HSC70 can effectively be designed only if we understand the fine relationships between HSC70 structure and functions.

Membrane HSP70: the molecule triggering gammadelta T cells in the early stage of tumorigenesis

Many studies support the supposition that HSPs expressed on the cell membrane play an important role in cancer immunity. In the present study, we demonstrated that HSP60 and HSP70 are markedly increased on the cell membrane of human Epstein-Barr virus (EBV) transformed B cells. In order to investigate whether these molecules were involved in the response of human gammasigma T cells to transformed cells, the cytotoxicities of gammasigma T cells to transformed cells with or without an HSP60/70 gene knockdown were evaluated. gammasigma T cells showed marked cytotoxities to transformed cells. Down-regulation of HSP70 expression could inhibit the reactions, whereas down-regulation of HSP60 expression had little such effect. Moreover, HSP72 could significantly induce human gammasigma T cells to proliferate in vitro. Taken together, our data indicated that HSP60 and HSP70 could be valuable biomarkers for the prediction of early stage in tumorigenesis. Additionally, HSP72 might be a potential candidate of the adjuvant for gammasigma T cells in tumor immunotherapy.