Occupational cohort and case–control studies suggest that trichloroethylene (TCE) exposure may be associated with non-Hodgkin lymphoma (NHL) but findings are not consistent. There is a need for mechanistic studies to evaluate the biologic plausibility of this association. We carried out a cross-sectional molecular epidemiology study of 80 healthy workers that used TCE and 96 comparable unexposed controls in Guangdong, China. Personal exposure measurements were taken over a three-week period before blood collection. Ninety-six percent of workers were exposed to TCE below the current US Occupational Safety and Health Administration Permissible Exposure Limit (100 p.p.m. 8 h time-weighted average), with a mean (SD) of 22.2 (36.0) p.p.m. The total lymphocyte count and each of the major lymphocyte subsets including CD4+ T cells, CD8+ T cells, natural killer (NK) cells and B cells were significantly decreased among the TCE-exposed workers compared with controls ( P < 0.05), with evidence of a dose-dependent decline. Further, there was a striking 61% decline in sCD27 plasma level and a 34% decline in sCD30 plasma level among TCE-exposed workers compared with controls. This is the first report that TCE exposure under the current Occupational Safety and Health Administration workplace standard is associated with a decline in all major lymphocyte subsets and sCD27 and sCD30, which play an important role in regulating cellular activity in subsets of T, B and NK cells and are associated with lymphocyte activation. Given that altered immunity is an established risk factor for NHL, these results add to the biologic plausibility that TCE is a possible lymphomagen.
Trichloroethylene (TCE) is a volatile chlorinated organic compound that is commonly used as a solvent for lipophilic compounds. Although recognized as an animal carcinogen, TCE's carcinogenic potential in humans is still uncertain. We have carried out a cross-sectional study of 80 workers exposed to TCE and 96 unexposed controls matched on age and sex in Guangdong, China to study TCE's early biologic effects. We previously reported that the total lymphocyte count and each of the major lymphocyte subsets (i.e., CD4(+) T cells, CD8(+) T cells, natural killer cells, and B cells) were decreased in TCE-exposed workers compared to controls, suggesting a selective effect on lymphoid progenitors, and/or lymphocyte survival. To explore which T lymphocyte subsets are affected in the same study population, we investigated the effect of TCE exposure on the numbers of CD4(+) naïve and memory T cells, CD8(+) naïve and memory T cells, and regulatory T cells by FACS analysis. Linear regression of each subset was used to test for differences between exposed workers and controls adjusting for potential confounders. We observed that CD4(+) and CD8(+) naïve T cell counts were about 8% (p = 0.056) and 17% (p = 0.0002) lower, respectively, among exposed workers. CD4(+) effector memory T cell counts were decreased by about 20% among TCE-exposed workers compared to controls (p = 0.001). The selective targeting of TCE on CD8(+) naive and possibly CD4(+) naive T cells, and CD4(+) effector memory T cells, provide further insights into the immunosuppression-related response of human immune cells upon TCE exposure.
To investigate the self-renewal mechanism of CD133+ cancer stem cells from Hep-2 cell line.The CD133+ cells were sorted by flow cytometry from Hep-2 cell line. Then the sorted CD133+ cells were cultured in RPMI1640. The ability of self-renewal of CD133+ cells were tested by MTT assay. mRNA and protein expression of self-renewal related genes were detected by western blot and RT- PCR.(3.10 ± 0.21)% of Hep-2 cells expressed the membrane antigen CD133. CD133+ fraction was raised to (90.20 ± 5.51)% by flow cytometry. In vitro culture and growth curve showed CD133+ cells had more active proliferation ability than CD133- cells, which showed statistically significant difference between these two group (P < 0.01). RT- PCR and western blot results showed upregulated mRNA and protein expression of Fas, c-myc, survivin in CD133+ group (P < 0.01). In the same time, the ratio of Bcl-2/Bax gene expression was obviously increased in CD133+ group. Self-renewal related gene such as β-catenin, SHH, SMOH and Bmi-1,Gli-1 were all up-regulated in CD133+ group both in mRNA and protein. On the contrary, PTCH gene was down-regulated.CD133 positive cells are a small proportion of a Hep-2 cell line. The results of this experiment verified that CD133 positive cells owned the properties of cancer stem cells. Upregulated anti-apoptotic gene is the foundatiom of self-renewal mechanism of CD133+ cells. Cancer stem cells related signal pathways such as Hedgehog, Wnt and Bmi-1 pathway are in state of activation. The identification of self-renewal mechanism about cancer stem cell provides a powerful tool to investigate the tumorigenic process in the larynx and to develop therapies targeting to these signal pathways.
Previous studies have explored the associations between parental and offspring's depression and parent-child communication. However, few studies have investigated their symptomatic associations and potential sex differences. Therefore, this study aims to examine their associations and sex differences in parents and offspring. Based on the China Family Panel Studies (CFPS)-2020 study, depressive symptoms and parent-child communication were measured by the 8-item Center for Epidemiologic Studies Depression Scale (CESD-8) and independent questions, respectively. Network analysis was used to investigate the associations and to compare the sex differences of parents and offspring. A total of 1710 adolescents were included after cleaning process (N = 28,530). There were significantly stronger associations in boys' "anhedonia" and "arguments with parents", and in girls' "happiness" and parents' "joyfulness". Furthermore, there were same-sex depression associations between children and parents (e.g., boys' "despair"–fathers' "joyfulness"; girls' "anhedonia"–mothers' "loneliness"). These results would help us to better understand the in depression and communication nuanced associations and to develop effective strategies for improving parental and offspring's mental health.
Objective To investigate the effect of glial cell line-derived neurotrophic factor(GDNF)on proliferation and differentiation of mouse spermatogonial stem cells in vitro.Methods The percoll discontinue density gradient centrifugation,followed by removing contaminated somatic cells through adhesion to plastic dishes,was used to purify the spermatogonial stem cells of Kunming mice.Mouse spermatogonial stem cells were confirmed by immunofluorescence and flow cytometry.The cells were divided into control groups and exprimental groups.The spermatogonial stem cells were cultured on sertoli cells.GDNF was added to medium of DMEM/F12.The growth of spermatogonial stem cells was determined by ELISA.The cell cycle of spermatogonial stem cells was determined by flow cytometry.Sperm was allied with ovum by intracytoplasmic sperm injection(ICSI).The chromosome figure and quantity were analysed after 3 days.Results A values of spermatogonial stem cells in experimental group were 0.362±0.031,0.448±0.028,0.502±0.062,0.556±0.045,0.621±0.072 in 3,6,9,12,15 days respectively;in control group,they were 0.365±0.045,0.377±0.053,0.402±0.071,0.432±0.019,0.461±0.037 respectively.Significant differences were noted between experimental group and controI group(P＜0.05).S period's quantities of DNA synthesizing were 20.86,26.34,31.23,37.54,28.02 in 3,6,9,12,15 days respectively,while they were 1.69,1.73.2.56,4.85,1.82 in 3,6,9,12,15 days in control group.Significant differences were noted between experimental group and control group(P＜0.05).The dual DNA could be found when sperm was integrated ovum after 3 days.Conclusions ICSI could identify spermatogial stem cells and translate into spermic cells in vitro.GDNF could improve the proliferation and differenciation of the spermatogonial stem cells in vitro.
Key words:
Spermatogonia; Glial cell line-derived neurotrophic factor; Cell culture; Mice
T-cell immunotherapy is showing great promise and therefore undergoing intensive developments for cancer treatment. In this study, we applied liposome-encapsulated Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) and CRISPR-associated protein-9 nuclease (Cas9) (CRISPR/Cas9) genome editing tool to specifically knock out the programmed death-1 (PD-1) gene from T cells (PD-1- T cells). We then activated these cells by dendritic/tumor fusion cells (FCs) and examined their anti-cancer potential. Results showed that, following the antigen presentation and activation by DC/HepG2 FCs, PD-1- T cells showed a significantly higher ability than PD-1+ T cells to proliferate, secrete pro-inflammatory cytokine IFN-γ, and kill HepG2 cells in vitro. Consistently, in vitro activated PD-1- T cells inhibited proliferation and induced apoptosis in HepG2 xenografts in vivo, leading to significantly suppressed tumor growth and improved mouse survival. Liposome-encapsulated CRISPR/Cas9 genome editing technology effectively knocked out PD-1 gene in T cells, stimulating T cell activation in response to DC/tumor FCs and affording T cell-mediated cancer immunotherapy. Our study provides evidence to target checkpoint receptors in adoptively transfected T cells, as a novel therapeutic modality for adoptive T cell transfer.
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