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Objective To investigate the presences of regulatory T cells (Treg) and natural killer T cell (NKT)-like T cells in the peripheral blood of healthy subjects and patients with newly diagnosed cancer. Methods Patients were enrolled into four groups: healthy subjects (Group A), patients without cancer (Group B), patients with newly diagnosed stage Ⅰ~Ⅱ cancer (Group C), and patients with newly diagnosed stage Ⅲ~Ⅳ cancer (Group D). Flow cytometry was performed to detect the percentage of CD4+ CD25high CD127low cells in CD4+ T lymphocytes (Treg) and the percentage of CD3+ CD56+ cells in CD3+ T lymphocytes (NKT-like). Results The percentage of Treg cells in CD4+T lymphocytes was(6.72 ± 3.16)%, (6.49 ± 2.83)%,(6.80 ± 3.07)%and (7.63 3.47)% in Group A, B, C and D, respectively, with no significant differences among these groups (P>0.05). However, the percentage of CD3+CD56+T cells in CD3+T lymphocytes was (3.13 ± 1.66)%, (2.56 ± 1.27)%,(7.22 ± 2.70)% and (7.72 ± 3.10)% in Group A, B, C and D, respectively, with marked increases in Group C and D compared to those in Group A and B (P < 0.05). Conclusion Patients with newly diagnosed cancer demonstrated increasing trends in the percentage of peripheral NKT-like cells.
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Objective To investigate the changes of phenotypes and function of CD56+T cells during primary HIV-1 infection and their relationship with disease progression.Methods Peripheral blood mononuclear cells (PBMCs) were collected from 53 subjects with primary HIV-1 infection and 31 HIV-1-negative healthy subjects.The percentages of CD56+T cells and the expression of several phenotypic markers on CD56+T cells including CD16, CD161, NKB1, NKG2A, NKp46, NKG2D, NKG2C and CD158a were analyzed by flow cytometry.IFN-γand TNF-αreleased by CD56+T cells with and without K562 stimulation and the levels of cytotoxic molecular CD107a were measured.Results The percentages of CD56+T cells in patients with primary HIV-1 infection were significantly lower than those of healthy subjects (P=0.025). The levels of CD56+T cells were negatively related to the viral loads in plasma samples ( P=0.021, r=-0.316).Compared with healthy subjects, the expression of CD16 (P=0.003), CD161 (P=0.023), NKB1 (P=0.023) and NKp46 (P=0.021) on CD56+T cells were decreased in patients with primary HIV-1 infection.The levels of NKB1 were positively related to the CD4+T cell counts ( P=0.007, r=0.364), but were negatively related to the viral loads in plasma samples (P=0.030, r=-0.299).Sponta-neous secretion of IFN-γand TNF-αby CD56+T cells and the expression of CD107a were dramatically in-hibited in patients with primary HIV-1 infection as compared with healthy subjects ( all P<0.001 ) . Moreover, the killing ability of CD56+T cells against K562 target cells was weakened in patients with prima-ry HIV-1 infection as the levels of IFN-γ-, TNF-α-and CD107a-producting CD56+T cells were significantly decreased (P<0.001 for IFN-γand TNF-α, P=0.016 for CD107a).Conclusion Inhibited expression and altered phenotypes of CD56+T cells were identified during primary HIV-1 infection.Lower levels of cy-tokines and cytotoxic molecular were also detected, indicating the dysfunction of CD56+T cells appeared dur-ing early stage of HIV-1 infection and was associated with disease progression.
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Objective To explore the cell frequency , phenotypes and in vitro cytotoxic effects of circulating CD56+T cells in the patients with chronic HCV infection .Methods Peripheral blood mononu-clear cells (PBMCs) were isolated from 33 patients with HCV chronic infection and 21 healthy subjects. Multi-color flow cytometry was used to analyze cell frequency , expressions of activating receptors ( NKG2C, CD16 and NKp46) and inhibitory receptors (NKG2A and CD158a) on CD56+T cells.The functional mark-er for cytotoxic effects (CD107a) on circulating CD56+T cells and their cytokines expression (IFN-γand TNF-α) with or without stimulation of K 562 human Leukemia cell line were also analyzed .Then the correla-tions among the expressing levels of CD 107 a, IFN-γand TNF-αwere investigated .Results The frequency of CD56+T cells in periphery lymphocytes were significantly decreased in the patients with chronic HCV in -fection as compared with that in healthy controls ( P=0.018 ).The expressions of activating receptors (NKG2C, CD16 and NKp46) on CD56+T cells from HCV infected patients were decreased (P=0.015 for NKG2C, P=0.036 for CD16 and P=0.001 for NKp46), while there was no significant change in the ex-pressions of inhibitory receptors (P>0.05 for both CD158a and NKG2A).The concentrations of IFN-γand TNF-αsecreted by CD56+T cells in the patients with chronic HCV infection were significantly decreased with or without K562 stimulation (P0.05). The expressions of CD107a, IFN-γand TNF-αwere closely related under the stimulation of K562(r>0.80, P<0.0001).Conclusion The frequency of CD56+T cells was reduced in patients with chronic HCV infec-tion.Moreover, cytotoxic effects and cytokines production mediated by CD 56+T cells were also significantly impaired, indicating that the dysfunction of circulating CD 56+T cells might be associated with the persist-ence of chronic HCV infection .