Therefore, the expression level of may modulate the function (e.g. Inc., Rockville, MD, USA) according to the instruction manual. RNA (05 g) was reverse transcribed with a SuperScript One-Step RT-PCR? System (Life Technologies, Inc.). The RT reaction was performed at 45C for 30 min and was then terminated by heating to 94C for 2 min. PCR consisted of 40 cycles of denaturation at 94C for 45 s, annealing at 53C for 1 min, and extension at 72C for 1 min. The sequence of the oligonucleotide primers were as follows: survivin-forward (5-AGGACCACCGCATCTCTAC-3), survivin-reverse (5-ACTTTCTTCGCAGTTTCCTC-3), FasL-forward (5-CACCCCAGTCCACCCCCTGA-3), FasL-reverse (5-AGGGGCAGGTTGTTGCAAGA-3), GAPDH-forward (5-GTGAAGGTCGGAGTCAACG-3), and GAPDH-reverse (5-GGTGAAGACGCCAGTGGACTC-3). The PCR products were separated on 2% agarose gel and were Calcifediol then transferred to a nylon membrane (Immobilon-S, Millipore Corporation, Bedford, MA, USA) with a semidry electroblotter (Nihon Eido Co. Ltd, Tokyo, Japan). Next, the PCR products were probed with a digoxigenin (DIG)-labelled internal probe (survivin internal probe: 5DIG-CACTGCCCCACTGAGAAC-3; FasL internal probe: 5DIG-CTGGAATGGGAAGACACCT-3) and visualized using the DIG Luminescent Detection Kit for Nucleic Acids (Boehringer Mannheim, Mannheim, Germany) according to the manufacturer’s instructions. In the case of GAPDH (used as an internal standard), the agarose gel was stained with ethidium bromide and visualized by UV light. Analysis of V TCR repertoire of regular T cells and CD57+ T cells The cells were analysed by three-colour flow cytometry using PE-anti- TCR antibody, PC5-anti-CD56 antibody, FITC-anti-CD57 antibody and various PE-anti-V TCR antibodies (V1, 2, 51, 8, 9, Rabbit Polyclonal to MRPL32 14, 17 and Calcifediol 22) (Beckman Coulter). Anti-V TCR antibodies that reportedly reacted with relatively larger populations of T cells were selected and used in this study. The percentage of each V T cell population was determined as follows: Expression of TCR, CD3? and CD3 molecules The expression of TCR and CD3? molecules on the CD57C (regular ) T cells and CD57+T cells was examined by a regular three-colour fluorescence-based surface marker analysis. The expression of intracellular CD3 molecules was examined by the techniques as described in the instruction manual. In brief, the PBMC were stained with membrane-specific conjugated antibodies (FITC-anti-CD57 and PC5-anti- TCR) and incubated for 30 min at room temperature in the dark. After washing, the cells were fixed with 025% formaldehyde-phosphate-buffered saline (PBS) for 10 min. Then the membrane Calcifediol was then permeabilized by digitonin (100 g/ml) for 15 min on ice. The intracellular component of molecules Calcifediol in the CD3 complex was stained by PE-anti monoclonal antibody (clone 2H2D9, TIA-2, Immunotech) in a saturating concentration. In each case, the stained cells were assessed by a flow cytometric analysis, and then the mean fluorescence intensity of the TCR, CD3? and CD3 molecules was measured. Statistical analysis Differences between the two groups (regular T cells and CD57+ T cells) were analysed by Student’s < 005. Results High susceptibility of CD57+ T cells to apoptosis in response to CD3-stimulation Purified regular T cells and CD57+ T cells were stimulated with anti-CD3 antibody and the susceptibility to apoptosis was compared by a flow cytometric analysis using PI and FITC-annexin V staining (Fig. 1a, left). T cells maintained a high viability (>90%) during the observation period and the frequency of apoptotic cells was very small. In contrast, a remarkable increase in annexin V-positive (apoptotic) or both annexin V- and PI-positive (post-apoptotic necrosis) fractions was observed in CD57+ T cells from 12 h after CD3-stimulation. The apoptotic fraction reached more than 40% of the cultured CD57+ T cells at 48 h (Fig. 1a, right). This suggests that apoptotic cell death and post-apoptotic necrosis were actively induced in CD57+ T cells after stimulation with anti-CD3 antibody. Open Calcifediol in a separate window Fig. 1 Apoptosis and apoptosis-related molecules of CD57+ T cells after stimulation with anti-CD3 antibody or anti- TCR antibody. (a) Time-course of CD3-stimulated apoptosis in regular T cells and CD57+ T cells. Representative results are shown from repeated experiments with similar results. Left: each T cell population was stimulated with anti-CD3 antibody for 12, 24 and 48 h and stained with propidium iodide (PI) and FITC-annexin V and was then analysed by flow cytometry. Right: the percentages of the apoptotic (annexin V-positive and PI-negative) cells, necrotic (PI-positive) cells and viable (both annexin V and PI-negative) cells were calculated from the results of the flow cytometric analyses and displayed as a function of the time after CD3-stimulation. (b) The expression of cell-surface Fas molecules in regular T cells and CD57+ T cells after CD3-stimulation. Left: flow cytometry results for expression of Fas in each T cell population at 24 and 48 h after stimulation with anti-CD3 antibody. Middle: a histogram overlay of the results of regular T.