MBL在结肠直肠癌中的基因分型

目的：MBL是补体激活凝集素途径的关键因素。MBL基因多态性影响MBL血清水平。结肠直肠癌患者血清MBL水平升高。低水平的MBL则预示着术后肺炎的发生,目前还不清楚此相关性是否与遗传相关。本实验分析调查了结肠直肠癌患者和健康对照者的MBL基因分型,评估基因分析和复发率、生存率之间潜在的相关性。方法：使用TaqMan基因分型分析法和实时定量PCR分析MBL基因的4个SNP、启动子区2个SNP、非编码区1个SNP;ELISA测定标本血清MBL含量。结果：所有标本中发现了8种不同的MBL单体型,它们在患者和健康者中出现频率几乎是完全一样的;YA/YA基因型与高水平的MBL相关,YO／YO与低水平的MBL水平相关,6种不同基因型CRC患者的MBL水平存在着明显不同。结论：MBL基因型与血清MBL浓度显薯相关（P〈0．0001）;突变型B,C,D和启动子单体型Y,X对MBL含量的影响起主要作用;MBL基因型和术后感染并发症没有明显相关性（P=0．33）,与复发癌和存活时间也没有明显相关性（P=0．74）。因此,从基因水平还不能解释为何结肠直肠癌患者血清MBL水平增加。对比已经检测出的血清MBL水平,其基因型还不能预测结肠直肠癌患者的疾病进程。     

精神分裂症患者甘露糖结合凝集素基因启动子区多态性及血清浓度的研究

目的:探讨精神分裂症患者甘露糖结合凝集素(MBL)的血清浓度和启动子区基因多态性的相关性及在患者免疫病理机制中的作用。方法:选取2018年6月至2018年12月在我院就诊的精神分裂患者为54例为观察组,另选取同时期本院健康体检中心志愿者56例为正常对照组,采用合酶链反应-序列特异性引物(PCR-SSP)技术分析MBL基因启动子区H/L(-550bp G/C)和X/Y(-221bp C/G)的多态性,酶联免疫吸附法(ELISA)检测血清MBL的浓度。结果:观察组血清MBL浓度(1367.218±1277.429)ng/mL低于正常对照组(1987.781±976.748)ng/mL,差异有统计学意义(P0.05)。观察组HY/HY基因型频率低于对照组(P0.05),HY/LY型频率高于对照组(P0.05)。观察组HY/HY基因型血清MBL浓度明显高于HY/LX、LY/LX型(P0.05);观察组MBL基因启动子区突变型纯合子的血清MBL水平均与对照组差异无统计学意义(P0.05),而MBL基因型杂合子的MBL水平则差异有统计学意义(P0.05)。结论:精神分裂症患者MBL水平低下与患者MBL基因启动子区各基因型的综合调控有关。MBL浓度低下是精神分裂症患者循环免疫复合物(CIC)滞留或清除障碍的分子机制之一。     

广西巴马小型猪MCP-1、MMP-9基因启动子区SNP位点与动脉粥样硬化相关血清指标的关联分析

本研究目的是分析广西巴马小型猪MCP-1和MMP-9基因启动子区SNP位点与血清指标的关联性,筛选可能与动脉粥样硬化相关的高风险分子标记,为后续培育广西巴马小型猪动脉粥样硬化疾病模型易感家系打下基础。采用PCR-RFLP对90头正常饲喂的广西巴马小型猪的MCP-1和MMP-9基因启动子区SNP位点进行分型,统计该位点的基因型频率和等位基因频率,比较分析基因型频率与动脉粥样硬化相关血清指标的关联性。结果显示,广西巴马小型猪MMP-9基因-1267位点、-1287位点和MCP-1基因-1782位点均存在3种基因型:AA型、AG型和GG型。MCP-1基因-1782位点和MMP-9基因-1267位点以GG型为优势基因型,MMP-9基因-1287位点以AG型为优势基因型。MMP-9基因两个突变位点的各基因型个体的血清指标及其分析值之间差异均不显著。MCP-1基因-1782位点AG型个体血清LDL平均值和LDL/HDL比值均显著高于GG型个体(p0.05),AG型个体HDL和TC浓度均值、AI值稍高于GG型个体,但差异均不显著。MCP-1基因AG型个体患动脉粥样硬化疾病的风险高,可作为培育建模易感家系的分子标记。     

慢性乙型肝炎患者血清HBV基因分型

为了解长春市慢性乙型肝炎患者血清中的乙型肝炎病毒(HBV)基因型情况及其与临床特点的相关性,应用型特异性引物进行巢式PCR方法对长春市69例慢性乙型肝炎患者血清HBV进行基因分型检测。在69例血清标本中,B型10例(占14.5%);C型41例(占59.4%);B C混合型8例(占11.6%);未分型的患者共10例(占14.5%)。C基因型患者的HBV-DNA定量、HBeAg阳性率明显高于B基因型患者(HBV-DNA:P<0.01;HBeAg:χ2=3.98,P<0.05),C基因型患者肝功检查指标谷丙转氨酶(ALT)和总胆红素(TB IL)均较B基因型患者高(P<0.01)。长春地区存在HBV B基因型、C基因型、B C混合基因型及未分型,C基因型为优势基因,引起的肝脏活动性炎症较B基因型明显。     

TNF-α基因308位点的SNP与新疆维吾尔族2型糖尿病的易感性的关系

目的:研究TNF-α基因单核苷酸多态性(SNP)308G-A位点与新疆地区雏吾尔族人2型糖尿病之间的关系.方法:以聚合酶链式反应-限制性内切酶长度多态性(PCR-RFLP)技术,对120例2型糖尿病患者和120例正常对照者TNF-α基因308位点SNP多态性进行基因分型.采用酶联免疫法测定T2DM患者105例72例及正常对照98例血清TNF-α水平,利用统计学方法分析其影响因素.结果:SNP308多态性住点的基因型和等位基因频率在病例组和正常对照组中的分布存在差异,差异有统计学意义(P＜0.05);正常对照组血清TNF-α水平为(26.30±15.54)pg/ml较汉族人群低,病例组为(29.89±14.48)pg/ml,病例组与时照组TNF-α水平无差异(p＞0.05).病例组血清TNF-α与FPG、TC、FINS、LDL-C、HOMA-IR呈显著负相关.结论:(1)TNFΝα基因SNP308多态性位点与新疆地区维吾尔族人群2型糖尿病有明显相关性;(2)TNF-α水平在新疆维吾尔族糖尿病组与正常对照组之间差异无统计学意义.     

TLR4 基因启动子单核苷酸多态性与结直肠癌临床预后的关系

目的:探讨Toll样受体(TLR)基因启动子单核苷酸多态性(SNP)与结直肠癌临床预后的关系。方法:收集我院2006年1月到2010年1月收治的结直肠癌患者200例,通过PCR扩增外周血DNA,经过查找数据库发现TLR4基因启动子区域有rs137853920、ss77136219多态位点,对所有患者随访5年,比较不同手术方式、美国癌症联合委员会(AJCC)分期、分化程度患者的总生存时间(OS)率和疾病无进展时间(PFT)率,分析基因型频率以及单倍体频率对患者生存影响。结果:200例患者生存时间在4~60个月,中位生存时间为54个月,OS率和PFT率在不同手术方式、癌症AJCC分期、分化程度患者间差异均具有统计学意义(P0.05);对生存资料进行多因素的Cox回归分析,结果显示rs137853920基因多态位点基因型AA、AG、GG具有较好的预后(P0.05),而ss77136219基因多态位点基因型GG、GA、AA具有较差预后(P0.05)。rs137853920、ss77136219多态位点共有四个单倍体型分别为AA、AG、GA、GG,频率分别为26.3%、21.7%、38.5%、21.6%,经过Cox多因素分析AG型患者具有较好预后(P0.05),而GG型患者具有较差预后(P0.05)。结论:TLR4基因启动子SNP可以作为结直肠癌临床预后的特异指标。     

牛SNP芯片分型检出率和分型错误率对基因型填充准确率的影响

SNP芯片已被广泛应用于动植物的遗传研究和生产实践,其基因分型的准确性至关重要。但在实际应用中,常有一定数量的基因型因缺失而需要去估计(填充)。此外,由于各种原因,又常常需要在不同芯片的基因型之间相互填充彼此没有的SNP基因型,或从低密度SNP填充到高密度SNP基因型。因此,基因型填充准确率直接影响后续数据分析的准确性和可靠性。为深入了解基因型填充准确率的影响因素,本研究利用20 116头美国荷斯坦牛的50K SNP芯片基因分型数据,在SNP分型检出率与错误率存在相关和没有相关两种情形下,分别评估了上述两个因素对下游基因型填充准确率的影响。当两者不相关时,模拟的SNP分型检出率从100%降低到50%,SNP分型错误率由0%提升到50%。当两者存在相关时,基因分型的检出率和错误率之间的关系是基于一个实际数据中这两个变量之间的线性回归方程来确定,即模拟的SNP分型检出率从100%降低到50%,SNP分型错误率从0%升高到13.35%。最后,采用5折交叉验证的方法评估基因型填充的准确率。结果表明,当原始数据的SNP分型检出率与错误率彼此独立发生时,基因型填充的错误率受原始SNP分型检出率影响不大(P0.05),却随着原始SNP分型错误率的升高而显著提高(P0.01)。当原始数据的SNP分型检出率与错误率存在负相关时,基因型填充的错误率随着原始SNP分型检出率的降低而显著提高(P0.01)。在这两种情形下,建议SNP分型检出率应在90%以上,基因型填充准确率才能不低于98%。该结果可为提升实际的SNP分型和下游数据分析的质控提供参考依据。     

TNFa-308基因启动子多态性与新疆维吾尔族人乙型肝炎易感性的相关性研究

目的：研究TNF-α基因单核苷酸多态性（SNP）308G—A位点与新疆地区维吾尔族人乙型肝炎之间的关系。方法：以聚合酶链式反应－限制性内切酶长度多态性（PCR-RFLP）技术,对120例乙肝患者和120例正常对照者TNF—α基因SNP308多态性位点进行基因分型。结果：SNP308多态性位点G／G基因型和G／A基因型频率在病例组为77％和23％,正常对照组为88％和12％,2组基因型和等位基因频率分布差异有显著性（p〈0．05）。结论：TNF—α基因启动子308多态性位点与新疆维吾尔族人乙肝有明显相关性。     

血清白介素8基因多态性与食管鳞癌根治术后的相关性分析

摘要 目的：探讨与分析血清白细胞介素8（IL-8）基因多态性与食管鳞癌（ESCC）根治术后的相关性。方法：2017年8月到2020年6月选择在本院诊治的食管鳞癌患者98例作为研究对象,检测血清IL-8表达水平。所有患者都给予根治手术治疗,随访患者的预后并进行相关性分析。结果：所有患者术后随访到2021年7月,平均随访时间为25.69±2.58个月,死亡28例,死亡率为28.6 %（死亡组）。两组血清IL-8表达水平表达具有差异（P<0.05）。所有患者的基因型频率均符合Hardy-Weinberg这一平衡法则,表明本文所选取的样本均具有群体代表性。IL-8基因启动子rs4073A/T的AA基因型较死亡组高,TT基因型较死亡组低,两组A、T等位基因频率分布对比有差异（P<0.05）。直线相关性分析显示：IL-8基因启动子rs4073A/T的AA基因型、A等位基因、血清IL-8表达水平与预后死亡率存在相关性（P<0.05）。多因素logistic回归分析显示：IL-8基因启动子rs4073A/T的AA基因型、A等位基因、血清IL-8表达水平为导致患者随访死亡的主要因素（OR=2.051,3.094,P<0.05）。结论：食管鳞癌根治术后患者依然存在一定的死亡率,患者死亡与血清IL-8基因多态性存在相关性,同时多伴随有IL-8的高表达。IL-8基因启动子rs4073A/T的AA基因型、A等位基因、血清IL-8表达水平为导致患者死亡的主要因素。     

单羧酸转运蛋白基因SNP 与肝细胞肝癌预后的关联研究

目的:探讨单羧酸转运蛋白基因(monocarboxylate transporter,MCT)单核苷酸多态性(single nucleotide polymorphism,SNPs)与肝细胞肝癌(hepatocellular carcinoma,HCC)根治术患者预后的关系。方法:运用Sequenom i PLEX分型技术对830例原发性HCC患者MCT家族(MCT1、MCT2和MCT4)基因上的8个功能性SNP位点进行基因分型,并分析这些SNP与HCC患者预后的相关性。结果:MCT1基因rs1049434位点和MCT2基因rs995343位点基因型与HCC患者总体生存期及无复发生存期均显著相关(P0.05)。携带MCT1 AT基因型或TT基因型的患者死亡及复发风险均显著低于携带AA基因型的患者(HR=0.72;P=0.042或HR=0.64;P=0.002);携带MCT2 CT基因型或TT基因型的患者死亡及复发风险均显著高于携带CC基因型的患者(HR=1.64;P=0.018或HR=1.52;P=0.026)。而且,MCT1基因rs1049434位点和MCT2基因rs995343位点对HCC预后存在显著的累积效应,携带2个危险基因型的患者死亡及复发风险分别是没有危险基因型患者的2.16倍和2.54倍。此外,携带2个危险基因型的HCC患者在术后行TACE辅助治疗后死亡及复发风险均显著降低(P0.05)。结论:MCT1和MCT2基因上的功能性SNP位点有可能作为HCC根治术后预后评估和TACE辅助治疗反应预测的独立标志物。     

Preoperative mannan-binding lectin pathway and prognosis in colorectal cancer

Purpose: Deficiency of the mannan-binding lectin (MBL) pathway of innate immunity is associated with increased susceptibility to infections. In patients with colorectal cancer (CRC), postoperative infection is associated with poor prognosis. The aim of the present study was to evaluate (1) the relation between the MBL pathway and postoperative infectious complications and survival of patients resected for CRC, and (2) the role of MBL in acute phase response compared to C-reactive protein (CRP). Methods: Preoperative MBL concentration, MBL-associated serine protease (MBL/MASP) activity and CRP were determined in serum from 611 patients and 150 healthy controls. The patients were observed for 8 years. Postoperative infections, recurrence and survival were recorded. Results: The MBL pathway components were increased in the patients compared with the healthy controls (p<0.0001). Low MBL levels were predictive of pneumonia (p=0.01), and pneumonia (n=87) was associated with poor survival (p=0.003; HR=1.5; 95% CI, 1.1 to 1.9). MBL and MBL/MASP activity showed no correlation with CRP (Spearmans =0.02; 95% CI, –0.06 to 0.10). Conclusion: Low preoperative MBL levels are predictive of pneumonia, which is associated with poorer survival. MBL concentration and MBL/MASP activity was not predictive of other postoperative infections or long-term prognosis, and showed no correlation with CRP.     

The Relationship Between Serum Mannose-Binding Lectin Levels and Acute Ischemic Stroke Risk

Complement activation and inflammation have been suggested in the pathogenesis of stroke, mannose-binding lectin (MBL) were found to have roles during the process. The aim of this study was to investigate the relationship between acute ischemic stroke (AIS) and serum MBL levels in Chinese population. From January 1 to June 30 2013, all patients with first-ever AIS were recruited to participate in the study. Serum MBL levels and routine test were examined. The National Institutes of Health Stroke Scale (NIHSS) score was assessed on admission blinded to MBL levels. During the inclusion period, 148 patients with AIS were registered and completed study. The results indicated that the serum MBL levels were significantly (p < 0.0001) higher in acutely ischemic stroke patients as compared to normal controls [1,332; interquartile range (IQR) 996–2,134 μg/L and 897; IQR 678–1,100 μg/L, respectively]. There was a correlation between serum levels of MBL and NIHSS score [r (spearman) = 0.608, p < 0.0001). In multivariate analysis, serum MBL as a continuous variable was associated with an increased risk of AIS, after adjustment for above possible confounders (OR 1.002, 95 % CI 1.001–1.008; p < 0.0001). These results indicated that elevated MBL levels could be considered as an independent stroke risk factor in Chinese population, suggesting a role of MBL and the lectin pathway of complement activation in the pathogenesis of stroke.     

Absence of association between mannose-binding lectin gene polymorphisms and HIV-1 infection in a Colombian population

Mannose-binding lectin (MBL) is a calcium-dependent lectin shown to play an important role in innate immunity to infection by activating the classical complement pathway and phagocytosis. In vitro studies have shown that MBL is able to bind to the gp120 HIV-1 surface antigen, and variants of the gene are associated with increased risk of HIV infection among Scandinavians. We investigated the association of genetic MBL variants and HIV-1 infection in 278 Colombian HIV-infected and control individuals. MBL genotype frequencies were similar for both groups, and no association was detected between MBL alleles B, C, and D and susceptibility to HIV-1 infection ( P=1.0). Since there is a well-documented link between the tested MBL alleles and very low MBL serum concentration, these results do not support the hypothesis that MBL levels are a risk factor for HIV-1 infection in Colombia.     

Role of mannose binding lectin gene variants on its protein levels and macrophage phagocytosis with live Mycobacterium tuberculosis in pulmonary tuberculosis

Mannose-binding lectin (MBL) plays an important role in innate immunity. Functional mutant homozygotes of the MBL gene affect the serum MBL levels and have been correlated with disease susceptibility. We have studied the regulatory role of variant MBL genotypes on serum MBL level and macrophage phagocytosis with live Mycobacterium tuberculosis, and the lymphoproliferative response to M. tuberculosis culture filtrate antigen in pulmonary tuberculosis (PTB) patients (n = 48) and normal healthy subjects (NHS) (n = 58). The total serum MBL level was higher in PTB patients than in NHS (P = 0.0085). Patients and NHS with AA genotype (homozygotes of MBL - common alleles) showed a very high serum MBL level, and those with OO genotype (functional mutant homozygotes of MBL - less frequent alleles) showed a very low MBL level (AA vs. OO: NHS, P = 3.3 x 10(-9); PTB, P = 3.1 x 10(-9)). A significantly lower phagocytosis was observed in NHS with AA genotype than in NHS with AO (heterozygotes) genotype (P = 0.046). In PTB patients, no such difference was observed. A negative correlation of macrophage phagocytosis with MBL level was seen in patients and NHS (P = 0.019). Antigen-induced lymphoproliferative response was significantly decreased in PTB patients with AA genotype as compared with NHS with AA genotype (P = 0.036). The present study suggests that AA genotype with its associated higher serum MBL levels plays a regulatory role in immunity to tuberculosis than functional mutant homozygotes (OO genotype) with its associated lower level of MBL.     

Deficiency of functional mannose-binding lectin is not associated with infections in patients with systemic lupus erythematosus

Infection imposes a serious burden on patients with systemic lupus erythematosus (SLE). The increased infection rate in SLE patients has been attributed in part to defects of immune defence. Recently, the lectin pathway of complement activation has also been suggested to play a role in the occurrence of infections in SLE. In previous studies, SLE patients homozygous for mannose-binding lectin (MBL) variant alleles were at an increased risk of acquiring serious infections in comparison with patients who were heterozygous or homozygous for the normal allele. This association suggests a correlation between functional MBL level and occurrence of infections in SLE patients. We therefore investigated the biological activity of MBL and its relationship with the occurrence of infections in patients with SLE. Demographic and clinical data were collected in 103 patients with SLE. Functional MBL serum levels and MBL-induced C4 deposition were measured by enzyme-linked immunosorbent assay using mannan as coat and an MBL- or C4b-specific monoclonal antibody. The complete MBL-dependent pathway activity was determined by using an assay that measures the complete MBL pathway activity in serum, starting with binding of MBL to mannan, and was detected with a specific monoclonal antibody against C5b-9. Charts were systematically reviewed to obtain information on documented infections since diagnosis of SLE. Major infections were defined as infections requiring hospital admission and intravenous administration of antibiotics. In total, 115 infections since diagnosis of lupus, including 42 major infections, were documented in the 103 SLE patients (mean age 41 ± 13 years, mean disease duration 7 ± 4 years). The percentage of SLE patients with severe MBL deficiency was similar to that in 100 healthy controls: 13% versus 14%, respectively. Although deposition of C4 to mannan and MBL pathway activity were reduced in 21% and 43% of 103 SLE patients, respectively, neither functional MBL serum levels nor MBL pathway activity was associated with infections or major infections in regression analyses. In conclusion, SLE patients frequently suffer from infections, but deficiency of functional MBL does not confer additional risk.     

Deficiency of functional mannose-binding lectin is not associated with infections in patients with systemic lupus erythematosus

Infection imposes a serious burden on patients with systemic lupus erythematosus (SLE). The increased infection rate in SLE patients has been attributed in part to defects of immune defence. Recently, the lectin pathway of complement activation has also been suggested to play a role in the occurrence of infections in SLE. In previous studies, SLE patients homozygous for mannose-binding lectin (MBL) variant alleles were at an increased risk of acquiring serious infections in comparison with patients who were heterozygous or homozygous for the normal allele. This association suggests a correlation between functional MBL level and occurrence of infections in SLE patients. We therefore investigated the biological activity of MBL and its relationship with the occurrence of infections in patients with SLE. Demographic and clinical data were collected in 103 patients with SLE. Functional MBL serum levels and MBL-induced C4 deposition were measured by enzyme-linked immunosorbent assay using mannan as coat and an MBL- or C4b-specific monoclonal antibody. The complete MBL-dependent pathway activity was determined by using an assay that measures the complete MBL pathway activity in serum, starting with binding of MBL to mannan, and was detected with a specific monoclonal antibody against C5b-9. Charts were systematically reviewed to obtain information on documented infections since diagnosis of SLE. Major infections were defined as infections requiring hospital admission and intravenous administration of antibiotics. In total, 115 infections since diagnosis of lupus, including 42 major infections, were documented in the 103 SLE patients (mean age 41 +/- 13 years, mean disease duration 7 +/- 4 years). The percentage of SLE patients with severe MBL deficiency was similar to that in 100 healthy controls: 13% versus 14%, respectively. Although deposition of C4 to mannan and MBL pathway activity were reduced in 21% and 43% of 103 SLE patients, respectively, neither functional MBL serum levels nor MBL pathway activity was associated with infections or major infections in regression analyses. In conclusion, SLE patients frequently suffer from infections, but deficiency of functional MBL does not confer additional risk.     

系统性红斑狼疮患者血清MBL水平变化及其临床意义

目的：研究系统性红斑狼疮（SLE）患者外周血中甘露糖结合凝集素（MBL）水平与SLE的临床表现、经典的血清学指标及疾病活动性指数的相关性。方法：应用固相酶联免疫吸附（ELISA）法检测54例（其中活动期39例、缓解期15例）SLE患者和45名健康志愿者外周血MBL水平,同时检测SLE患者外周血抗dsDNA抗体、C3补体、白细胞计数及循环免疫复合物（CICs）水平,并记录SLE患者主要临床症状（肾脏系统受累、神经系统受累、严重感染等）,疾病活动度用SLEDAI记分。结果：系统性红斑狼疮患者外周血MBL水平显著低于健康志愿者（P〈0．01）;特别是活动期SLE患者血清MBL水平明显降低,与缓解组比较差别具有统计学意义（P〈0．01）;SLE患者血清MBL水平与SLEDAI、抗dsDNA抗体、CICs水平呈负相关,与白细胞计数及C3补体水平呈正相关;并发严重感染的SLE患者组血清MBL水平显著低于无受累组（P〈0．01）。结论：SLE患者血清MBL水平明显降低,血清MBL水平与SLEDAI、抗dsDNA抗体、C3水平、CIC水平、白细胞水平之间明显相关,血清MBL水平较低的患者更易发生比较严重的感染,血清MBL水平可能是SLE潜在生物学标记。     

Characterization of an equine mannose-binding lectin and its roles in disease

The mannose-binding lectin (MBL), a pattern recognition serum protein, participates in the innate immune system of mammals as an opsonin. In humans, MBL plays a key role in first-line host defense against infection during the lag period prior to the development of a specific immune response. MBL also activates complement via the lectin pathway that requires a MBL-associated serine protease-2 (MASP-2). Homologues of human MBL (hMBL) have been identified in a variety of mammals, fish, and primitive animals such as ascidians. In this study, we report that equine MBL (eMBL) has properties that are similar to hMBL. In addition, we found low levels of MBL:MASP activity in sick horses compared to healthy horses. These results suggest that eMBL is involved in the immune response of the horse and that low MBL:MASP activity could be used to monitor immune function and clinical outcome.