Abstract: Abstract:Objective To investigate the relevance between plasma content,plasma protein molecular forms and promoter region polymorphisms of mannose binding lectin(MBL) and ischemic cerebrovascular disease (ICVD).Methods The anti-coagulated blood of patients with ICVD (ICVD group,81 cases) and healthy people (control group,60 cases) was collected.The plasma level of MBL was measured by ELISA and the plasma MBL protein oligomeric forms were determined by Western blotting.The promoter region polymorphisms of MBL gene were analyzed by sequence specificprimers PCR (SSP-PCR).  Results  The plasma content of MBL in ICVD group (3 372.18  μg/L±660.90  μg/L)  was higher than that in control group (2 065.29   μg/L±195.67 μg/L) (P<0.01).The bands represented single MBL peptide sub-unit (approximately 36 000) and oligomeric forms (approximately 130 000 and 250 000) were deeper in ICVD group than those in control group.The constituent ratios of haplotype and genotype of MBL promoter region in ICVD group were significantly different from those in control group.There were  significant differences in the frequencies of haplotype HYP and LXP between ICVD patients(50.62%,6.79%) and controls(34.17%,20.83%) (P<0.05).HXP/HYP and HXP/LYQ genotypes were found only in ICVD patients,meanwhile,HXP/LXP and HYP/LXP genotypes only in controls.ICVD patients  had significantly lower frequency of genotype LYQ/LYQ(4.94%) compared with controls (15.00%)(P<0.05).Conclusion The plasma content,plasma protein molecular forms and constituent ratios of haplotype and genotype of MBL promoter region in ICVD patients are all different from those in healthy people,so MBL may be involved in the development and progression of ICVD.

Key words: ischemic cerebrovascular disease, mannose binding lectin, gene promoter , polymorphism, oligomeric forms