To investigate the distribution characteristics and linkage disequilibrium of T cell immunoglobulin domain and mucin domain protein 4 (TIM4) promoter polymorphisms in asthma patients of Chinese Han population, the promoter region of TIM4 was re-sequenced by PCR-sequencing, and linkage disequilibrium was analyzed by SHEsis software. Four single nucleotide polymor- phisms (SNPs) in the promoter region of TIM4 were detected, including two new SNPs (at positions -1609, -153) and two reported SNPs (rs6874202, rs6882076). The frequency distribution of rs6882076 was different among different races (P<0.05). In addition, linkage disequilibrium among the SNPs of the promoter region of TIM4 was found and GGTG was the predominant haplotype. There were four SNPs in the promoter region of TIM4 in asthma patients of Chinese Han population, which were in linkage disequilibrium.
T cell immunoglobulin mucin (TIM) family plays a key role in regulating immune re-sponses.In this study,the interactions of human TIM family with apoptotic cells were evaluated in order to provide a foundation for further study on the roles of human TIM genes in apoptosis.Nine kinds of pEGFP-N1 eukaryotic expression vectors containing different lengths of the three members of human TIM genes for the expression of TIM-EGFP and the vectors for the expression of TIM-Fc fusion pro-teins were constructed.It was found that human TIM proteins could recognize and bind to apoptotic cells directly,but not to viable cells.The interactions of sTIM-1-EGFP,sTIM-3-EGFP and sTIM-4-EGFP with apoptotic cells were blocked by TIM-1-Ig,TIM-3-Ig and TIM-4-Ig fusion proteins respectively.In addition,human TIM proteins mediated the recognition of apoptotic cells and bound to apoptotic cells directly via the IgV domains.In conclusion,the TIM family may play a key role in the regulation of apoptosis.Our data also suggest that human TIM proteins probably serve as novel proteins for the detection of the early cellular apoptosis.
