Chemokine-like factor 1 (CKLF1) is expressed in myocardial ischemia injury in vivo and in vitro

Introduction:Chemokine-like factor 1(CKLF1)is a chemokine that is overexpressed in several diseases.Our previousfindings revealed a significant increase in CKLF1 expression in the ischemic brain,suggesting its potential as a therapeutic target for ischemic stroke.Methods:In this study,we examined the expression dynamics of CKLF1 in both in vivo and in vitro models of ischemic cardiac injury.Myocardial infarction(MI)was induced in vivo by ligation of the left anterior descending artery(LAD)of the rat heart.The levels of CKLF1,Creatine Kinase MB Isoenzyme(CK-MB),and Lactate dehydrogenase(LDH)in the serum were detected using Enzyme-linked immunosorbent assay(ELISA).The expression of CKLF1 in the infarcted area was detected by immunohistochemistry,immunofluorescence,quantitative PCR(qPCR),and Western blotting(WB).H9C2 and AC16 cardiomyocytes cultured in vitro were subjected to oxygen and glucose deprivation(OGD).LDH was used to detect cell damage,and CKLF1 expression was detected by qPCR and WB.Results:CKLF1 mRNA and protein expression were significantly increased in h9c2 cells at 1.5 h and in AC16 cells at 4 h after OGD.The serum CK-MB in rats increased significantly on thefirst day after infarction,while the LDH concentration increased significantly on the third day after infarction.CKLF1 blood levels significantly increased on thefirst day following MI in rats.CKLF1 expression notably increased in the infarct area on days 1,3,and 7 post-MI.In MI tissue,CKLF1 colocalizes with cardiomyocytes,macrophages,and neutrophils.Conclusion:CKLF1 was substantially expressed during myocardial ischemia injury both in vivo and in vitro and was colocalized with macrophages and neutrophils,indicating that CKLF1 is expected to be a biomarker and a drug target for the treatment of myocardial infarction.

Inhibition of chemokine-like factor 1 improves bloodbrain barrier dysfunction in rats following focal cerebral ischemia

OBJECTIVE To investigate the role of chemokine-like factor 1(CKLF1),a novel C-C chemokine,on brain-blood barrier(BBB)integrity in rat focal cerebral ischemia and reperfusion model.METHODS Antibodies against CKLF1 was applied to the rightcerebral ventricle immediately after transient middle cerebral artery occlusion.Brain water content,Evans blue leakage and the expression of aquaporin-4(AQP-4),matrix metalloproteinase-9(MMP-9),zonula occludens-1(ZO-1)and occludin were measured.RESULTS After treatment with antiCKLF1 antibody,brain water content and Evans blue leakage in ipsilateral hemisphere were decreased in a dose-dependent manner at 24 h after reperfusion,but not changed in contralateral hemisphere.Anti-CKLF1 antibody reduced the expression of AQP-4 and MMP-9,and upregulated the expression of ZO-1 and Occludin.These results suggest that CKLF1 is involved in BBB disruption after reperfusion.CONCLUSION Inhibition of CKLF1 protects against cerebral ischemia by maintaining BBB integrity,possibly via inhibiting the expression of AQP-4 and MMP-9,and increasing the expression of tight junction protein.

Distinct Expression of Chemokine-like Factor 1 in Synovium of Osteoarthritis, Rheumatoid Arthritis and Ankylosing Spondylitis

Chemokine-like factor 1（CKLF1） is a newly cloned chemotactic cytokine with CCR4 being its functional receptor. Recent evidence demonstrates a role of CKLF1 in arthritis. The aim of this study was to quantify the expression of CKLF1 as well as assess the correlation between CKLF1 and plasma acute-phase markers. Synovium was obtained from 16 osteoarthritis（OA）, 15 rheumatoid arthritis（RA） and 10 ankylosing spondylitis（AS） patients undergoing total joint arthroplasty, with other 11 patients treated for meniscal tears during sport accidents serving as normal controls. Levels of CKLF1 and CCR4 m RNA were detected by q RT-PCR, and the expression of CKLF1 was investigated by immunohistochemistry staining, subsequently analyzed with semiquantitative scores. Plasma acute-phase markers of inflammation were determined by ELISA. CKLF1 was found with a particularly up-regulated expression in synovim from AS and RA patients, and CCR4 m RNA levels increased in RA patients, not in OA or AS patients. Elevated levels of plasma markers of inflammation including CRP, ESR and Ddimer were observed in RA. Further, significantly positive correlations between relative expression levels of CKLF1 and CRP/ESR in RA patients and a positive correlation between CKLF1 and ESR in AS patients were found. There was no detectable correlation between CKLF1 and plasma D-dimer. This study confirms an increased but different level of CKLF1 in RA, OA and AS patients, all significantly higher than that in controls. Additionally, the significant positive correlations between CKLF1 levels and CRP/ESR in RA and between CKLF1 and ESR suggest that CKLF1 might contribute to the inflammation state and clinical symptoms in these rheumatic diseases. Further studies are required to investigate the utility of targeting specific CKLF1 for symptom control or disease modification in RA and AS.

趋化素样因子-1在狼疮性肾炎患者肾组织中的表达

目的:探讨趋化素样因子-1(chemokine like factor-1,CKLF-1)在狼疮性肾炎的发生、发展过程中的作用。方法:对34例确诊为狼疮性肾炎以及10例对照组患者的肾组织进行免疫组织化学染色,在光镜下观察肾小球CKLF-1阳性细胞率和CKLF-1阳性肾小管百分率及反应强度。结果:狼疮性肾炎患者的肾小球CKLF-1阳性细胞率和CKLF-1阳性肾小管百分率分别为10.4%±1.5%和48.9%±4.3%,与对照组患者4.6%±1.1%和4.3%±0.9%比较均有统计学差异(P<0.01)。CKLF-1在狼疮性肾炎患者的肾小球阳性细胞率和阳性肾小管百分率与狼疮性肾炎活动指数间均存在显著相关性,相关系数分别为0.74和0.53(P<0.05)。结论:CKLF-1参与了狼疮性肾炎的发生、发展过程。

GDF-15 Level Correlates with CMKLR1 and VEGF-A in Tumor-free Margin in Colorectal Cancer

Colorectal cancer(CRC)is the third most frequently diagnosed cancer worldwide,responsible for over 880000 deaths each year.Growth/differentiation factor 15(GDF-15)is reported to be a promising diagnostic and prognostic factor in CRC.It induces pleiotropic effects in tumor cells:proliferation,sternness,invasion and metastasis.Some studies indicate that GDF-15 may stimulate angiogenesis in malignant neoplasms.However,it has not been investigated in CRC yet.The aim of our study was to determine the level of GDF-15 and the concentrations of hypoxia-inducible factor-la(HIF-1α),VEGF-A and chemokine-like receptor 1(CMKLR1)in tumor and margin specimens of CRC in relation to histological grade and TNM staging.The study comprised 33 samples of tumor and margin tissues obtained from CRC patients.To assess the concentration of GDF-15,HIF-1α,VEGF-A and CMKLR1,commercially available enzyme-linked immunosorbent assay(ELISA)kits were used.We found significantly increased levels of GDF-15 and CMKLR1 in tumor tissue compared to margin tissue and higher concentrations of HIF-1α and VEGF-A in margin tissue than in tumor tissue.The levels of GDF-15 and HIF-1α were significantly correlated with VEGF-A and CMKLR1 in margin tissue.In CRC,the increased level of GDF-15 might stimulate angiogenesis through upregulation of HIF-1α,VEGF A and CMKLR1 expression.Our study is the first one to reveal the correlation between the levels of GDF-15 and CMKLR1 in CRC.The elevated levels of HIF-1α and VEGF-A in tumor-free margin tissues suggest that noncancer cells in the tumor microenvironment are an important source of proangiogenic factors.

Chemokine-like factor 1,a novel cytokine,contributes to airway damage,remodeling and pulmonary fibrosis

Background Chemokine-like factor 1 (CKLF1) was recently identified as a novel cytokine The full-length CKLF1 cDNA contains 530 bp encoding 99 amino acid residues with a CC motif similar to that of other CC family chemokines Recombinant CKLF1 exhibits chemotactic activity on leucocytes and stimulates proliferation of murine skeletal muscle cells We questioned whether CKLF1 could be involved in the pathogenesis of inflammation and proliferation in the lung Therefore we used efficient in vivo gene delivery method to investigate the biological effect of CKLF1 in the murine lung Methods CKLF1-expressing plasmid, pCDI-CKLF1, was constructed and injected into the skeletal muscles followed by electroporation Lung tissues were obtained at the end of week 1,2,3 and 4 respectively after injection The pathological changes in the lungs were observed by light microscope Results A single intramuscular injection of CKLF1 plasmid DNA into BALB/c mice caused dramatic pathological changes in the lungs of treated mice These changes included peribronchial leukocyte infiltration, epithelial shedding, collagen deposition, proliferation of bronchial smooth muscle cells and fibrosis of the lung Conclusions The sustained morphological abnormalities of the bronchial and bronchiolar wall, the acute pneumonitis and interstitial pulmonary fibrosis induced by CKLF1 were similar to phenomena observed in chronic persistent asthma, acute respiratory distress syndrome and severe acute respiratory syndrome These data suggest that CKLF1 may play an important role in the pathogenesis of these important diseases and the study also implies that gene electro-transfer in vivo could serve as a valuable approach for evaluating the function of a novel gene in animals

CMTM6在消化道肿瘤中的研究进展

CKLF样MARVEL跨膜结构域成员(CMTM)家族是一种新基因家族,CMTM6是其中重要一员。程序性死亡配体1(PD-L1)是一种免疫检查点抑制分子,其可参与介导肿瘤细胞的免疫逃逸。研究表明,CMTM6与PD-L1结合后,可稳定细胞表面PD-L1的表达,从而实现肿瘤细胞的免疫逃逸,提示CMTM6可能在调节肿瘤细胞免疫抑制方面起着一定的作用,继而为肿瘤的免疫治疗提供了新的思路。本篇综述对CMTM6及其在消化系统肿瘤中的研究进展进行作一介绍。