Elevated serum FGF21 is an independent predictor for adverse events in hemodialysis patients from two large centers: a prospective cohort study.

Introduction: We explored the relationship and the predictive value of serum fibroblast growth factor 21 (FGF21) with all-cause mortality, major adverse cardiovascular events (MACEs) and pneumonia in hemodialysis (HD) patients.Methods: A total of 388 Chinese HD patients from two HD centers were finally enrolled in this prospective cohort study (registration number: ChiCTR 1900028249) between January 2018 and December 2018. Serum FGF21 was detected. Patients were followed up with a median period of 47 months to record the MACEs and pneumonia until death or 31 December 2022.Results: The incidence of all-cause mortality, MACEs and pneumonia in HD patients were 20.6%, 29.6%, and 34.8%, respectively. The optimal cutoffs for FGF21 to predict all-cause mortality, MACEs and pneumonia were 437.57 pg/mL, 216.99 pg/mL and 112.79 pg/mL. Multivariate Cox regression analyses showed that FGF21, as a categorical variable, was an independent predictor for all-cause mortality, MACEs and pneumonia (HR, 3.357, 95% CI, 2.128-5.295, p < 0.001; HR, 1.575, 95% CI, 1.046-2.371, p = 0.029; HR, 1.784; 95% CI, 1.124-2.830; p = 0.014, respectively). The survival nomogram, MACEs-free survival nomogram and pneumonia-free survival nomogram based on FGF21 constructed for individualized assessment of HD patients had a high C-index with 0.841, 0.706 and 0.734.Conclusion: Higher serum FGF21 is an independent predictor of all-cause mortality, MACEs and pneumonia in HD patients.

USP7 promotes the osteoclast differentiation of CD14+ human peripheral blood monocytes in osteoporosis via HMGB1 deubiquitination.

Background: Abnormal osteoclast and osteoblast differentiation is an essential pathological process in osteoporosis. As an important deubiquitinase enzyme, ubiquitin-specific peptidase 7 (USP7) participates in various disease processes through posttranslational modification. However, the mechanism by which USP7 regulates osteoporosis remains unknown. Herein, we aimed to investigate whether USP7 regulates abnormal osteoclast differentiation in osteoporosis. Methods: The gene expression profiles of blood monocytes were preprocessed to analyze the differential expression of USP genes. CD14+ peripheral blood mononuclear cells (PBMCs) were isolated from whole blood collected from osteoporosis patients (OPs) and healthy donors (HDs), and the expression pattern of USP7 during the differentiation of CD14+ PBMCs into osteoclasts was detected by western blotting. The role of USP7 in the osteoclast differentiation of PBMCs treated with USP7 siRNA or exogenous rUSP7 was further investigated by the F-actin assay, TRAP staining and western blotting. Moreover, the interaction between high-mobility group protein 1 (HMGB1) and USP7 was investigated by coimmunoprecipitation, and the regulation of the USP7-HMGB1 axis in osteoclast differentiation was further verified. Osteoporosis in ovariectomized (OVX) mice was then studied using the USP7-specific inhibitor P5091 to identify the role of USP7 in osteoporosis. Results: The bioinformatic analyses and CD14+ PBMCs from osteoporosis patients confirmed that the upregulation of USP7 was associated with osteoporosis. USP7 positively regulates the osteoclast differentiation of CD14+ PBMCs in vitro. Mechanistically, USP7 promoted osteoclast formation by binding to and deubiquitination of HMGB1. In vivo, P5091 effectively attenuates bone loss in OVX mice. Conclusion: We demonstrate that USP7 promotes the differentiation of CD14+ PBMCs into osteoclasts via HMGB1 deubiquitination and that inhibition of USP7 effectively attenuates bone loss in osteoporosis in vivo.The translational potential of this article:The study reveals novel insights into the role of USP7 in the progression of osteoporosis and provides a new therapeutic target for the treatment of osteoporosis.

Assessment of stroke knowledge and awareness among primary healthcare providers: A cross-sectional survey from the Kezhou quality improvement in acute stroke care project.

Objective: Acute stroke care is a highly complex type of emergency medical service (EMS) involving patient-centered care in a highly unpredictable and stressful environment with the help of several busy providers. The ability of primary healthcare providers (PHPs) to identify stroke onset early and further manage referrals to higher-level hospitals becomes critical. Methods: We conducted a cross-sectional survey about stroke knowledge and awareness among PHPs in China from September 2021 to December 2021. A total of 289 PHPs were divided into two groups, the stroke treatment window (STW) Aware group vs. the STW Unaware group according to their knowledge on the time window for acute ischemic stroke (AIS) management. Logistic regression analysis was performed to explore the predictors associated with knowledge of the time window for acute stroke management. Results: Of 289 PHPs surveyed during the study period, 115 (39.7%) participants were aware of the time window for stroke management and were in the STW Aware group, while 174 (60.2%) were in the STW Unaware group. Forty percent of PHPs in the STW Aware group were familiar with the secondary stroke prevention goal of <140/90 mmHg, compared with 27.01% in the Unaware group (P < 0.05). PHPs were not sufficiently aware of loss of consciousness also a symptom of stroke in two groups (75.7 vs. 62.6%, P < 0.05). A higher proportion of PHPs in the STW Aware group believed that thrombolysis was an effective treatment for AIS (96.5 vs. 79.9%, P < 0.01). Endovascular therapy is indicated for AIS was perceived by a higher proportion of PHPs in the STW Aware group than that in the Unaware group (62.6 vs. 6.9%, P < 0.01). Eighty percent of PHPs in the STW Aware group reported attending training on stroke management compared with 58.1% in the Unaware group (P < 0.01). Logistic regression results showed that the predictors of stroke knowledge and awareness among PHPs included sex (OR: 2.3, 95% CI, 1.2-4.6), received training (OR: 2.9, 95% CI, 1.60-5.1), and times of training per year (OR: 0.70, 95% CI, 0.6-0.9). Conclusions: PHPs present with a mild to moderate level of stroke management knowledge in northwest China. Strategies to help increase stroke knowledge and awareness among PHPs should be considered in order to help improve the stroke related health service system.

Real-time feedback on mobile application use for emergency management affects the door-to-needle time and functional outcomes in acute ischemic stroke.

OBJECTIVES: Time from onset to reperfusion affects mortality and favorable outcomes in patients with acute ischemic stroke (AIS). To evaluate effects of a real-time feedback mobile application on critical time intervals and functional outcomes in stroke emergency management. METHODS: We recruited patients with clinically suspected acute stroke from December 1st, 2020 until July 30st, 2022. All Patients had a non-contrast computed tomography (CT) and were included only if they had AIS. We divided the patients into two groups based on the date of availability on mobile application: pre-APP group and post-APP group. Onset to Door time (ODT), Door to Imaging Time (DIT), Door to Needle Time (DNT), Door to Puncture Time (DPT), Door to Recanalization Time (DRT), National Institutes of Health Stroke Scale (NIHSS) and modified Rankin Scale (mRS) were compared between two groups. RESULTS: We retrospectively enrolled 312 AIS patients who were assigned into the pre-APP group (n = 159) and post-APP group (n = 153). The median ODT time and median admission NIHSS score were not significantly different between the two groups at baseline assessment. The median (IQR) DIT [44 (30-60) min vs 28 (20-36) min, P < 0.01] and DNT [44 (36.25-52) min vs 39 (29-45) min, P = 0.02] both decreased significantly in two groups. However, median DPT and DRT time showed no significant differences. The proportion of mRS score of 0 to 2 at day 90 was significantly higher in the post-App group than in the pre-App group, at 82.4% and 71.7%, respectively (dominance ratio OR=1.84, 95% CI: 1.07 to 3.16, P = 0.03). CONCLUSION: The present findings indicate that the real-time feedback of stroke emergency management used by a mobile application have potential for shortening the DIT and DNT time and improve the prognosis of stroke patients.

Mechanical thrombectomy for acute multivessel occlusions with duplicated middle cerebral artery: A case report.

Acute multivessel occlusions generally have multisite clot burden with lower successful reperfusion rates, and cerebrovascular anatomical variants increase the challenge of endovascular clot retrieval. We report a case of acute anterior multivessel occlusions patient with duplicated middle cerebral artery. Combined balloon guide catheter with stent retriever and aspiration approach has gained complete revascularization and good functional outcomes at 3 months follow-up.

Recent advances of single-cell RNA sequencing technology in mesenchymal stem cell research.

Mesenchymal stem cells (MSCs) are multipotent stromal cells with great potential for clinical applications. However, little is known about their cell heterogeneity at a single-cell resolution, which severely impedes the development of MSC therapy. In this review, we focus on advances in the identification of novel surface markers and functional subpopulations of MSCs made by single-cell RNA sequencing and discuss their participation in the pathophysiology of stem cells and related diseases. The challenges and future directions of single-cell RNA sequencing in MSCs are also addressed in this review.

Long non-coding RNA: The functional regulator of mesenchymal stem cells.

Mesenchymal stem cells (MSCs) are a subset of multipotent stroma cells residing in various tissues of the body. Apart from supporting the hematopoietic stem cell niche, MSCs possess strong immunoregulatory ability and multiple differentiation potentials. These powerful capacities allow the extensive application of MSCs in clinical practice as an effective treatment for diseases. Therefore, illuminating the functional mechanism of MSCs will help to improve their curative effect and promote their clinical use. Long noncoding RNA (LncRNA) is a novel class of noncoding RNA longer than 200 nt. Recently, multiple studies have demonstrated that LncRNA is widely involved in growth and development through controlling the fate of cells, including MSCs. In this review, we highlight the role of LncRNA in regulating the functions of MSCs and discuss their participation in the pathogenesis of diseases and clinical use in diagnosis and treatment.

Presence of lacunar infarctions is associated with the spatial navigation impairment in patients with mild cognitive impairment: a DTI study.

Lacunar cerebral infarction (LI) is one of risk factors of vascular dementia and correlates with progression of cognitive impairment including the executive functions. However, little is known on spatial navigation impairment and its underlying microstructural alteration of white matter in patients with LI and with or without mild cognitive impairment (MCI). Our aim was to investigate whether the spatial navigation impairment correlated with the white matter integrity in LI patients with MCI (LI-MCI). Thirty patients with LI were included in the study and were divided into LI-MCI (n=17) and non MCI (LI-Non MCI) groups (n=13) according neuropsychological tests.The microstructural integrity of white matter was assessed by calculating a fractional anisotropy (FA) and mean diffusivity (MD) from diffusion tensor imaging (DTI) scans. The spatial navigation accuracy, separately evaluated as egocentric and allocentric, was assessed by a computerized human analogue of the Morris Water Maze tests Amunet. LI-MCI performed worse than the CN and LI-NonMCI groups on egocentric and delayed spatial navigation subtests. LI-MCI patients have spatial navigation deficits. The microstructural abnormalities in diffuse brain regions, including hippocampus, uncinate fasciculus and other brain regions may contribute to the spatial navigation impairment in LI-MCI patients at follow-up.

Habitual coffee consumption and risk of cognitive decline/dementia: A systematic review and meta-analysis of prospective cohort studies.

OBJECTIVE: Findings from epidemiologic studies of coffee consumption and risk for cognitive decline or dementia are inconclusive. The aim of this study was to conduct a meta-analysis of prospective studies to assess the association between coffee consumption and the risk for cognitive decline and dementia. METHODS: Relevant studies were identified by searching PubMed and Embase databases between 1966 and December 2014. Prospective cohorts that reported relative risk (RRs) and 95% confidence intervals (CIs) for the association of coffee consumption with dementia incidence or cognitive changing were eligible. Study-specific RRs were combined by using a random-effects model. RESULTS: Eleven prospective studies, including 29,155 participants, were included in the meta-analysis. The combined RR indicated that high coffee consumption was not associated with the different measures of cognitive decline or dementia (summary RR, 0.97; 95% CI, 0.84-1.11). Subgroup analyses suggested a significant inverse association between highest coffee consumption and the risk for Alzheimer disease (summary RR, 0.73; 95% CI, 0.55-0.97). The dose-response analysis, including eight studies, did not show an association between the increment of coffee intake and cognitive decline or dementia risk (an increment of 1 cup/d of coffee consumed; summary RR, 1.00; 95% CI, 0.98-1.02). CONCLUSIONS: The present study suggests that higher coffee consumption is associated with reduced risk for Alzheimer disease. Further randomized controlled trials or well-designed cohort studies are needed to determine the association between coffee consumption and cognitive decline or dementia.

[Spatio-temporal variation of drought condition during 1961 to 2012 based on composite index of meteorological drought in Altay region, China].

Based on the daily meteorological data of seven stations in Altay region, China, this study investigated the temporal ( seasonal, inter-annual and decadal) and spatial variations of drought by using composite index of meteorological drought, as well as trend analysis, M-K abrupt analysis, wavelet analysis and interpolation tools in ArcGIS. The results indicated that the composite index of meteorological drought could reflect the drought condition in Altay region well. Although the frequency and the covered area of both inter-annual and seasonal droughts presented decreasing trends in the recent 52 a, the drought was still serious when considering the annual drought. The frequencies of inter-annual and spring droughts had no abrupt changes, whereas the frequencies of inter-summer, autumn and winter droughts had abrupt changes during the past 52 a. A significant periodic trend was also observed for the frequencies of inter-annual and seasonal droughts. The distribution of frequency and covered area suggested that the conditions of drought were heavily serious in Qinghe County, moderately serious in Altay City, Fuyun County, Buerjin County and Fuhai County, and slightly serious in Habahe County and Jimunai County.

Clinical significance of serum transforming growth factor-ß1 in lung cancer.

BACKGROUND: Transforming growth factor-ß1 (TGF-ß1) plays a critical role in human cancer development. Present study aimed to explore the clinical significance of serum TGF-ß1 levels in patients with lung cancer and analyze the relationship between TGF-ß1 and existing tumor markers for lung cancer. METHODS: Serum was collected from 118 patients with lung cancer and 40 healthy volunteers. Serum TGF-ß1 levels were measured by enzyme-linked immunosorbent assay (ELISA), and the association with various clinical characteristics was analyzed. The diagnostic value of TGF-ß1 was assessed alone and in combination with existing tumor markers for lung cancer. RESULTS: Serum TGF-ß1 levels were significantly higher in patients with lung cancer compared to healthy volunteers [0.6 × 10(5) (0.4 × 10(5), 0.9 × 10(5))pg/ml vs 0.5 × 10(5) (0.3 × 10(5), 0.7 × 10(5))pg/ml, P=0.040]. Although there was a positive correlation between serum TGF-ß1 levels and advanced stages, the significant difference was not found between early stages and advanced stages (P=0.116). The ability of serum TGF-ß1 to discriminate lung cancer at a cutoff value of 79,168 pg/ml exhibited sensitivity of 30.6% and specificity of 97.5%. Serum TGF-ß1 levels were correlated to cytokeratin fragment 21-1 (CYFRA21-1; R=0.308, P=0.020) and neuron-specific enolase (NSE; R=0.558, P=0.003). The diagnostic accuracy rates for the existing lung-tumor markers, as SCC, CYFRA21-1, and NSE, were increased from 20.0%, 34.6%, and 45.9% to 48.9%, 51.7%, and 54.5%, respectively by the inclusion of serum TGF-ß1 levels. CONCLUSION: Quantification of serum TGF-ß1 levels by ELISA may provide a novel complementary tool for the clinical diagnosis of lung cancer.

Cotton PRP5 gene encoding a proline-rich protein is involved in fiber development.

Proline-rich proteins contribute to cell wall structure of specific cell types and are involved in plant growth and development. In this study, a fiber-specific gene, GhPRP5, encoding a proline-rich protein was functionally characterized in cotton. GhPRP5 promoter directed GUS expression only in trichomes of both transgenic Arabidopsis and tobacco plants. The transgenic Arabidopsis plants with overexpressing GhPRP5 displayed reduced cell growth, resulting in smaller cell size and consequently plant dwarfs, in comparison with wild type plants. In contrast, knock-down of GhPRP5 expression by RNA interference in cotton enhanced fiber development. The fiber length of transgenic cotton plants was longer than that of wild type. In addition, some genes involved in fiber elongation and wall biosynthesis of cotton were up-regulated or down-regulated in the transgenic cotton plants owing to suppression of GhPRP5. Collectively, these data suggested that GhPRP5 protein as a negative regulator participates in modulating fiber development of cotton.

Clinical significance of serum mitochondrial DNA in lung cancer.

OBJECTIVES: The aim of the study was to investigate the clinical significance of serum mitochondrial DNA (mtDNA) in lung cancer. DESIGN AND METHODS: Serum mtDNA from 65 lung cancer patients, 20 patients with benign lung diseases and 55 healthy individuals was quantified using real-time fluorescent quantitative polymerase chain reaction (FQ-PCR). Data were analyzed using statistical software SPSS 13.0. RESULTS: Serum mtDNA levels in lung cancer patients were significantly higher, compared to those in patients with benign lung diseases and healthy individuals (u=108, p=0.000; u=293, p=0.000), and closely associated with TNM stage (p=0.01). The use of serum mtDNA facilitated detection of lung cancer at a cutoff value of 0.74×104 copies/µL with a sensitivity of 86.2% and specificity of 80.7%. However, serum mtDNA levels were not associated with patient age, gender, histological type, and lymph node metastasis (p>0.05). CONCLUSIONS: Quantification of serum mtDNA using FQ-PCR potentially serves as a novel complementary tool to improve the clinical screening and detection of lung cancer.

Quantification of serum HBXAP DNA in lung cancer patients by quantitative fluorescent polymerase chain reaction.

Hepatitis B virus x associated protein (HBXAP), as a subunit of chromatin remodeling and spacing factor, plays a critical role in cancer development through gene amplification. In this study, we aimed to quantify the levels of serum HBXAP DNA, to analyze and compare its diagnostic value with existing clinical parameters in lung cancer, and to potentially provide a novel tumor marker for lung cancer. Serum HBXAP DNA from 65 lung cancer patients and 20 healthy controls was quantified using real-time fluorescent quantitative polymerase chain reaction (FQ-PCR) analysis. The data were analyzed by statistical software SPSS 13.0. We found that serum HBXAP DNA levels in lung cancer patients were higher compared to healthy controls (u = 219.0, p = 0.001) and were closely associated with TNM stage and lymph node metastasis (p = 0.015 and p = 0.016, respectively). However, serum HBXAP DNA levels were not associated with patient age, gender, smoking status, histological type, or tumor size (p > 0.05). We identified a sensitivity of 61.9 % and a specificity of 93.7 % for the ability of HBXAP DNA levels to detect lung cancer at a cutoff value of 1,557.6 copies/µl. The sensitivity for existing lung-tumor markers, such as squamous cell carcinoma antigen, cytokeratin fragment 21-1, and neuron specific enolase, was increased from 35.7 %, 53.5 %, and 56.0 % to 75.0 %, 86.0 %, and 80.0 %, respectively, by inclusion of serum HBXAP DNA. Taken together, quantification of serum HBXAP DNA by FQ-PCR could potentially serve as a novel complementary tool for the clinical screening and detection of lung cancer.

Analysis of methylprednisolone-induced inhibition on the proliferation of neural progenitor cells in vitro by gene expression profiling.

Recently, it has been proved that methylprednisolone has inhibition effect on the proliferation of endogenous neural progenitor cells (NPCs) after spinal cord injury (SCI). Similar effect has also been found on NPCs cultured in vitro. However, the mechanism remains to be fully delineated. The purpose of this study is to investigate the potential molecular mechanism of this effect in NPCs cultured in vitro by gene expression profiling. Fetal mouse brain-derived NPCs were divided into 2 groups: NPCs incubated with methylprednisolone as a model of the methylprednisolone treatment after SCI, and without methylprednisolone as the control group. After the cell quantitative analysis and CCK-8 assay, the microarray analysis was carried out. Genes differentially expressed between NPCs treated with and without methylprednisolone were extracted. It was observed that the expression of 143 genes, including many members of distinct families, such as hypoxia inducible factors and neurotransmitter receptors, were significantly changed in response to the methylprednisolone treatment. Our results provide global molecular insights into the mechanisms of methylprednisolone-induced proliferation inhibition effect and suggest that EdnrB may play an important role in this effect.

Association between body mass index and erosive esophagitis: a meta-analysis.

AIM: To conduct a meta-analysis to estimate the determinants of the association between erosive esophagitis (EE) and body mass index (BMI). METHODS: We identified the studies using PubMed. Studies were selected for analysis based on certain inclusion and exclusion criteria. Data were extracted from each study on the basis of predefined items. Meta-analyses were performed to verify the risk factors, such as obesity and gender. RESULTS: Twenty-one studies were included in this systematic review. These studies demonstrated an association between increasing BMI and the presence of EE [95% confidence interval (CI): 1.35-1.88, overweight, odds ratio (OR) = 1.60, P value homogeneity = 0.003, 95% CI: 1.65-2.55, obese, OR = 2.05, P < 0.01]. The heterogeneity disappeared by stratifying for gender. No publication bias was observed in this meta-analysis by the Egger method. CONCLUSION: This analysis demonstrates a positive association between BMI and the presence of EE, especially in males. The risk seems to progressively increase with increasing weight.

Application of mesenchymal stromal cells in bone marrow transplantation for sensitized recipients.

Sensitized patients are at high risk for graft rejection during transplantation. It is of interest to investigate the effect of mesenchymal stromal cells (MSCs) in sensitized hematopoietic stem cell transplantation. MSCs were generated from bone marrow cells of BALB/c mice. The molecular markers of MSCs were detected by flow cytometry. MSCs labeled with green fluorescent dye were transplanted into nonsensitized and sensitized recipients, respectively. Homing of MSCs in vivo was monitored at different time points post-transplantation. Additionally, sensitized BALB/c mice under irradiation were transplanted with syngeneic MSCs and allogeneic bone marrow cells, and the rate of survival was monitored daily. The fourth passage of MSCs presented a typical spindle-shaped morphology and met the identification criteria of MSCs. Forty-eight hours post-transplantation, the homing of MSCs was found mainly in the bone morrow of nonsensitized recipients and the spleen of sensitized recipients, respectively. Moreover, all of the sensitized recipients died 12-16 days after receiving syngeneic MSCs and allogeneic bone marrow cells, with a median of 14 days. Our results suggest that the MSCs mainly homed to the spleen of sensitized recipients post-transplantation. MSCs could not enhance the engraftment of allogeneic bone marrow cells in sensitized recipients.

Rosiglitazone enhances the proliferation of neural progenitor cells and inhibits inflammation response after spinal cord injury.

It has been previously shown that peroxisome proliferators-activated receptor gamma (PPAR-γ) is beneficial for nervous system injury. In present study, we examined the effect of rosiglitazone, a PPAR-γ agonist, on spinal cord injury (SCI) in rats. SCI was induced by dropping a 10g weight rod at a height of 25mm. The animals were randomly divided into vehicle group, rosiglitazone treated group, and G3335 treated group. Locomotor function recovery was evaluated by the Basso-Beattie-Bresnahan locomotor rating scale (BBB scale), NF-κB expression and endogenous neural progenitor cells (NPCs) proliferation and differentiation was assessed by flow cytometry and immunohistochemistry. Compared with the vehicle groups, we found that the rosiglitazone could significantly ameliorate locomotor recovery, reduce NF-κB expression, and increase the proliferation of endogenous NPCs. when the PPAR-γ antagonist was use, these effects were abolished. However, neurons differentiating from endogenous NPCs were inhibited when PPAR-γ was activated. Our results suggest that the activation of PPAR-γ may be a potential alternative treatment for spinal cord injury.

[Expression of perforin in cord blood NK cells after IL-2/IL-15 stimulation and its relation with cytotoxicity].

This study was aimed to investigate the expression level of perforin in cord blood NK cells and the relation of perforin expression after IL-2, IL-15 stimulation to cytotoxicity of NK cells. NK cells were isolated from cord blood MNC by depleting CD3(+) cells and then enriching CD56(+) cells using immunomagnetic separation (CD3 and CD56 cell isolation kit, autoMACS, miltenyi). The purity was analysed by flow cytometry. According to the different combination of cytokines, there were two groups: group A (IL-2) and group B (IL-2 + IL-15). The cytotoxicity and perforin expression rate of fresh and different cultured CB-NK cells against K562/Jurkat cell lines were estimated by LDH release test (cytotoxic 96 non-radioactive cytotoxicity assay). The results showed that the purity of NK cells after separation was more than 90%. The cytotoxicity towards both tumor lines in group B was higher than that in group A (p < 0.05), and cytotoxicity in group A was higher than that of fresh NK cells (p < 0.05). Perforin expression rate of group A (84.55%) was higher than that of fresh NK cells (67.21%) (p < 0.05), and there was no significant difference between group A and B (84.55% versus 87.22%) Cytotoxic activity of CB-NK cells was positively correlated with perforin expression rate (r = 0.886, p < 0.05). It is concluded that IL-2 can enhance cytotoxicity of CB/BM-NK cells by increasing the perforin expression.

[Cytotoxic effect of IL-2/IL-15 stimulated cord blood derived NK cells on K562/Jurkat cell lines].

The aim of this study was to explore the cytotoxicity of fresh cord blood(CB) NK cells and the influence of IL-12 and IL-15 on activity of the NK cells killing K562 and Jurkat cells lines. The NK cells were isolated from cord blood by depleting CD3(+) cells and then enriching CD56(+) cells using sorting with immunomagnetic beads. The experiment was divided into 3 groups: group A (fresh CB-NK cells without cytokines), group B (CB-NK cells cultured by IL-2) and group C (CB-NK cells cultured by IL-2 and IL-15). The purity of NK cells was determined by flow cytometry; the cytotoxity of fresh and different cytokine-treated CB-NK cells on K562 and Jurkat cell lines was detected by LDH release test. The results showed that the purity of NK cells before and after sorting was 14.88 ± 9.2% and 92.39 ± 0.8% respectively. After culture for 3 days, NK-forming colony amounts in group B and group C were 148.60 ± 13.0 and 831.80 ± 23.0 respectively, the comparison between group B and group C showed the significant difference (p < 0.05). The cytotoxicities of NK cells in group A, B and C on K562 and Jurkat cell lines were 27.76 ± 8.8%, 61.90 ± 9.1% and 87.62 ± 3.7%; 29.32 ± 2.5%, 69.43 ± 4.4% and 92.95 ± 3.2% respectively, the difference was significant (p < 0.05). It is concluded that the fresh isolated CB-NK cells show low cytotoxic activity. After stimulated with IL-2 or IL-2 plus IL15, cytotoxicity of CB-NK cells increases obviously, the effect of IL-2 plus IL-15 is much better than IL-2 alone for promoting the growth and enhancing the cytotoxicity of CB-NK cells.