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Objective To observe the change of T helper 17 (Th17),regulatory T cell (Treg) as a percentage of lymphocytes and the Th17/Treg ratio in peripheral blood of patients with coal-burning-borne arsenic poisoning,and to explore the role of Th17 cells and Treg cells balance in arsenic-induced immune injury.Methods A case-control study was conducted to investigate 149 cases of arsenic poisoning in Yuzhang arsenic poisoning area in the southwestern Gnizhou Province,and the age was (50.69 ± 6.14) years old,including 94 males and 55 females.The diagnosis was based on the "Diagnosis of Endemic Arsenicosis" (WS/T 211-2015),and the cases were divided into mild arsenic poisoning group (39 cases),moderate arsenic poisoning group (54 cases) and severe arsenic poisoning group (56 cases);forty--one residents of non-arsenic exposed villages about 12 km away from the diseased area were collected as control group,the age was (45.76 ± 7.88) years old,including 12 males and 29 females.Hair samples and peripheral blood were collected from the subjects.The content of hair arsenic was detected by inductively coupled plasma mass spectrometry (ICP-MS).The percentages of Th17 cells and Treg cells in peripheral blood lymphocytes were detected by flow cytometry,and changes in the ratio of Th17/Treg in each group were analyzed.Results The hair arsenic contents in control,mild,moderate,and severe arsenic poisoning groups [median (quartile)] were 0.12 (0.08-0.18),0.20 (0.16-0.33),0.25 (0.18-0.41),0.28 (0.21-0.50) μg/g,and the differences were statistically significant between groups (H =52.22,P ＜ 0.01),and the hair arsenic content in each arsenic poisoning group was higher than that of the control group (P ＜ 0.05).The percentages of Th17 cells in peripheral blood lymphocytes of moderate and severe arsenic poisoning groups [(0.42 ± 0.21)％,(0.41 ± 0.23)％] were higher than that of the control group [(0.29 ± 0.16)％,P ＜ 0.05].The percentages of Treg cells in peripheral blood lymphocytes of mild,moderate and severe arsenic poisoning groups [(0.37 ± 0.18)％,(0.31 ± 0.19)％,(0.27 ± 0.18)％] were lower than that of the control group [(0.71 ± 0.20)％,P ＜ 0.05];with respect to the mild arsenic poisoning group,the percentage of Treg cells in severe arsenic poisoning group was reduced (P ＜ 0.05).The ratios of Th17/Treg in mild,moderate and severe arsenic poisoning groups (1.17 ± 0.63,1.56 ± 0.69,1.83 ± 0.85) were higher than that of the control group (0.43 ± 0.22,P ＜ 0.05);compared with mild arsenic poisoning group,the ratio of Th17/Treg in severe arsenic poisoning group was elevated (P ＜ 0.05).Correlation analysis showed that the hair arsenic content was positively correlated with the percentage of Th17 cells in peripheral blood lymphocytes and the ratio of Th17/Treg (r =0.323,0.608,P ＜ 0.05),and negatively correlated with the percentage of Treg cells in peripheral blood lymphocytes (r =-0.486,P ＜ 0.05).Conclusion Coal-burning-borne arsenic poisoning can cause the proportion of Th17 cells in the peripheral blood of patients to increase in lymphocytes,and the proportion of Treg cells in lymphocytes to decrease,which in turn changes the balance of Th17/Treg,resulting in weakened immune tolerance and disorder the regulation of inflammatory response,thus participates in the occurrence and development of arsenic-induced immune damage.
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Objective To investigate the expression of transcription factor forkhead/winged helix transcription factor 3 (Foxp3),immune factor transforming growth factor-beta 1 (TGF-β1),and T-lymphocyte activation related factor interleukin-2 (IL-2) in peripheral blood of patients with coal-burning arsenic poisoning,and to analyze the effects of arsenic exposure on immune function.Methods A case-control study was conducted to investigate 149 cases [94 males and 55 females,(50.69 ± 6.14) years old] of arsenic poisoning in Yuzhang coalburning arsenic poisoning area,southwestern Guizhou Province,and the cases were diagnosed based on the "Diagnosis of Endemic Arsenicosis" (WS/T 211-2015) and confirmed by clinical review.According to skin damage,the patients were divided into mild arsenic poisoning group (39 cases),moderate arsenic poisoning group (54 cases) and severe arsenic poisoning group (56 cases);and 41 cases [12 males and 29 females,(45.76 ± 7.88) years old] of non-arsenic exposed residents from 12 km of Yuzhang coal-burning area were selected as control group.Morning urine and peripheral blood samples were collected with informed consent.Urine arsenic content was measured by inductively coupled plasma mass spectrometry (ICP-MS).Urine arsenic was corrected by creatinine (Cr).Detection of regulatory T cell (Treg)-specific transcription factor Foxp3 gene expression in human peripheral blood was done by real-time fluorescence quantitative PCR,and the levels of Treg-related immune factor TGF-β1 and IL-2 in serum were detected by enzyme linked immunosorbent assay (ELISA).Results The urinary arsenic contents [median (quartile):29.13 (19.75-54.50),31.81 (17.52-53.31),30.51 (18.35-45.76) μg/g Cr] in each arsenic poisoning group were higher than that in the control group [21.62 (17.65-28.44) μg/g Cr,P ＜ 0.05].The expression levels of Foxp3 mRNA in peripheral blood of each arsenic poisoning group [median (quartile):0.58 (0.17-1.27),0.32 (0.17-0.61),0.33 (0.13-0.62)] were significantly lower than that in the control group [0.87 (0.64-1.50),P ＜ 0.05];compared with mild arsenic poisoning group,the expression of Foxp3 mRNA in peripheral blood of moderate and severe arsenic poisoning groups decreased (P ＜ 0.05).The contents of serum TGF-β1 [(13.14 ± 5.19),(12.85 ± 5.51),(12.78 ± 4.95) μg/L] in each arsenic poisoning group were significantly higher than that in the control group [(3.90 ± 1.53) μg/L,P ＜ 0.05].The levels of IL-2 in serum of each arsenic poisoning group [(9.85 ± 5.38),(11.64 ± 6.40),(12.27 ± 6.19) ng/L] were lower than that in the control group [(34.30 ± 4.84) ng/L,P ＜ 0.05];the serum level of IL-2 in severe arsenic poisoning group was higher than that in mild arsenic poisoning group (P ＜ 0.05).Conclusions Arsenic exposure can cause abnormal changes of Treg-specific transcription factor Foxp3 and related immune factors TGF-β1 and IL-2 in peripheral blood of patients.It is suggested that Treg dysfunction may be related to arsenic poisoning.
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Objective To investigate the infiltration of T helper 17 (Th17) and regulatory T cells (Treg) in the liver of rats exposed to arsenic,and to investigate the roles of Th17 and Treg in infiltration of liver injury induced by arsenic.Methods Thirty-two Wistar rats,half male and half female,were randomly divided into control,low,medium and high arsenic dose groups by body weight via the random number table method,8 rats per group.Rats in control group were given oral garage of deionized water,while other groups were given oral gavage doses of 2.00 g/L sodium arsenite (NaAsO2) according to their body weight for 6 days every week,the concentrations of NaAsO2 were 1.25,2.50 and 5.00 ml/kg,respectively.After 4 months,liver tissue samples of rats were collected,the content of arsenic in liver was determined by inductively coupled plasma mass spectrometry (ICP-MS);Hematoxylin-eosin staining (HE) method was used to observe the morphological changes of liver tissue in rats;the protein expressions of interleukin-17A (IL-17A,the imflammatory factor secreted by Th17 cells) and Forkhead Box P3 (Foxp3,the lineage-specific transcription factor of Treg cells) were measured with immunohistochemistry.Results ① Arsenic content in liver of low,medium,and high arsenic exposed groups [63.83 (52.79-80.26),59.16 (51.38-76.58),79.26 (69.59-107.44) μg/g] were higher than those of the control group [2.86 (1.76-3.56)μg/g,P ＜ 0.05],and the high arsenic dose group was higher than the medium arsenic dose group (P ＜ 0.05).② With increasing doses of arsenic,the numbers of inflammatory cells in the liver tissue of rats were increased,and the liver tissue of the high arsenic dose group showed vacuolar degeneration and pathological changes in some areas.③ Compared with the control group,low and medium arsenic dose groups (0.001 + 0.001,0.010 ± 0.020,0.030 ± 0.080),the expression of IL-17A protein in the liver in high arsenic dose group were significantly increased (0.220 ± 0.130,P ＜ 0.05),the differences were statistically significant between groups (F =14.776,P ＜0.05).The expressions of Foxp3 protein in the liver in low,medium,and high arsenic dose groups were significantly higher (0.270 ± 0.050,0.330 ± 0.040,0.320 ± 0.070) than that in the control group (0.070 ± 0.020),the differences were statistically significant between groups (F =56.990,P ＜ 0.05).④ There was a positive correlation between hepatic arsenic levels and protein levels of IL-17A and Foxp3 in liver (r =0.48,0.81,P ＜ 0.05).Conclusion Arsenic exposure can increase the content of arsenic in liver tissue of rats,which causes the changes of infiltration of Th17 and Treg cells,leading to the change of immune status,suggesting that Thl7 and Treg cells play an important role in the development of arsenic-induced immune injury.
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Objective To observe the differential expression level of CD4+CD25+Foxp3+regulatory T cells (Treg) in liver of arsenic-exposed rats, explore the regulatory mechanisms on immunological of hepatic injury induced by arsenic, and provide a basis for prevention and treatment of the disease. Methods Thirty-two healthy Wistar rats were selected and randomly divided into control,low,medium and high arsenic dose groups by weight,8 rats per group. Rats in control group were given oral gavage of deionized water, while the other groups were given oral gavage doses of 2.00 g/L sodium arsenite(NaAsO2) according to their body weight for 6 days every week, the concentrations were 1.25, 2.50 and 5.00 ml/kg. After 4 months, liver tissue samples of rats were collected, the content of arsenic in liver was detected by inductively coupled plasma mass spectrometry (ICP-MS);the expression of Treg cells in liver was detected by immunohistochemistry; enzyme-linked immunosorbent assay (ELISA) was applied to detect the levels of interloukin-10 (IL-10),transforming growth factor beta 1 (TGF-β1), IL-6, IL-17 and IL-2. Results Compared with the control group [28.57 (17.64 - 35.64)μg/g], the content of arsenic in liver in low,medium and high arsenic exposed groups[M(P25-P75):638.30(527.91-802.58),591.64(513.82-723.16),792.55 (695.93 - 1 074.41) μg/g] increased, the differences were statistically significant(P < 0.05). Compared with low arsenic group, the content of arsenic in liver in high arsenic group increased, the difference was statistically significant (P < 0.05). Numerical density on area (NA) of positive Treg cells in medium,high arsenic exposed groups [(2.25 ± 0.50),(4.00 ± 2.16)A/cm2]was higher than that of the control group[(0.60 ± 0.54)A/cm2,P<0.05];NA of positive Treg cells in high arsenic exposed group was higher than that of the low arsenic exposed group[(1.50 ± 0.58) A/cm2, P < 0.05]. The expressions of the IL-10 in low, medium and high arsenic exposed groups [(5.58 ± 1.70), (6.78 ± 1.09),(7.18 ± 0.53)μg/L]were higher than that of the control group[(2.32 ± 0.83) μg/L,P<0.05];compared with low arsenic group, the expression of IL-10 in high arsenic group increased (P < 0.05); compared with control group [(1.46 ± 0.65) μg/L], the expression of TGF-β1 in high arsenic exposed group increased[(9.06 ± 3.60)μg/L, P<0.05];compared with control group [(2.33 ± 0.66)μg/L], the expression of IL-6 in high arsenic exposed group increased [(5.03 ± 1.39) μg/L, P < 0.05], compared with low arsenic exposed group [(2.46 ± 1.71) μg/L], the expressions of IL-6 in high arsenic exposed group increased, the difference was statistically significant (P < 0.05);the expression of IL-17 among control, low, medium and high arsenic exposed groups[(4.87 ± 1.64),(7.50 ± 2.74), (6.21 ± 1.47),(7.23 ± 2.68)μg/L]were not statistically significant (F = 1.429, P > 0.05); compared with control group [(16.30 ± 3.98) μg/L], the expression of IL-2 in high arsenic exposed group decreased[(9.93 ± 2.65) μg/L, P <0.05]. The content of arsenic in liver was positively correlated with the expression of IL-10, TGF-β1, IL-17, IL-6 (rs=0.696,0.463,0.632,0.502,P<0.05),and negatively correlated with the expression of IL-2(rs=-0.522,P<0.05). Conclusion With increasing of arsenic exposure level, the content of arsenic in liver and the expression of CD4+CD25+Foxp3+Treg have increased,the cytokines are secreted abnormally,liver immunological micro environment is disordered,immune tolerance is formed,and immune clearance is inhibited,which may play an important role in the occur and development of immunological liver damage induced by arsenic in rat.
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Objective To investigate the differential expression levels and significance of regulatory T cell (Treg) and T helper 17 (Th17) related immunologic factors in peripheral blood of arsenic-exposed rats.Methods Thirty-two Wistar rats were numbered by weight,randomly divided into four groups [control,low (1.25 ml/kg),medium (2.50 ml/kg),and high (5.00 ml/kg)],8 rats per group.Rats in control group were given oral gavage of deionized water,and low,medium and high arsenic exposed groups were given oral gavage doses of 2.00 g/L sodium arsenite (NaAsO2) according to their body weight for 6 days every week.After 4 months,the urine and peripheral blood samples of rats were collected,urinary arsenic (uAs) was detected by inductively coupled plasma-mass spectrometry (ICP-MS),the results were shown in [median (minimum and maximum)],uAs was corrected by urinary creatinine (uCr),the unit was μg/g Cr;enzyme-linked immune-sorbent assay (ELISA) was applied to detect the levels of Treg,Th17,T lymphocytes activation related immunologic factors [interleukin-10 (IL-10),transforming growth factor beta1 (TGF-31),IL-17,IL-6,IL-2],the results were shown in (x) ± s.Results The uAs of the rats was compared between control,low,medium,and high arsenic exposed groups [7.50 (3.16-9.81),72.34 (62.34-106.63),209.15 (154.41-232.20),369.73 (289.50-516.55) μg/g Cr],the differences were statistically significant (F =337.55,P ＜ 0.05).IL-10 [(85.03 ± 7.11),(93.96 ± 8.14),(97.48 ± 6.23),(93.47 ± 4.41) ng/L],TGF-β1 [(72.88 ± 2.96),(81.45 ± 8.15),(86.08 ± 7.55),(90.29 ± 5.35) ng/L],IL-17 [(18.15 ± 3.66),(25.54 ± 5.59),(31.48 ± 5.74),(37.25 ± 7.36) ng/L],IL-6 [(83.68 ± 8.48),(85.14 ± 7.11),(89.78 ± 5.36),(93.48 ± 5.77) ng/L],and IL-2 [(80.65 ± 6.90),(73.86 ± 8.00),(69.93 ± 7.77),(62.06 ± 9.82) ng/L] of the rats were compared between control,low,medium,and high arsenic exposed groups,the differences were statistically significant (F =5.094,11.054,16.249,3.474,5.119,all P ＜ 0.05).There were positive correlations between uAs and TGF-β1,IL-17 concentration (r =0.723,0.605,all P ＜ 0.01),while IL-2 showed a negative correlation (r =-0.484,P ＜ 0.05).Concltsion Arsenic exposure could affect the secretion of Treg and Th17 related immunologic factors,so as to the imbalance of anti-inflammatory and pro-inflammatory,which may play a role in the formation and development of arsenic-related immune injury.