The Primary Research Of Toll-like Receptor-4 And Toll-like Receptor-2 Gene Polymorphisms And Natural Antibody Titers Of ABO Blood Group System Of Healthy Population In Dalian

Background: In recent years natural antibodies have become one of the research hotspots on the field of biology and immunology. Natural antibodies which exist at ABO,MNSs,P and Lewis blood group system are products of immune responses and they are not inherent substances when people are born. Natural antibodies of ABO blood group system have important significance on the fields of clinical blood transfusion,organ transplantation and haemopoietic stem cell transplantation.There are prodigious differences of natural anti-A/B antibody titers in population while the mechanisms of natural antibody formation are not quite definite yet.It is possible that these natural antibodies are generated by the recessive stimulation of substances such as bacterium,pollen grains and dust which may have the same epitopes with A and B antigen of red blood cells.Springer has discovered that antibodies against human B antigen of red blood cells were detected in chickens which hatched out several months ago while there were no antibodies against human B antigen of red blood cells in chickens always in aseptic environment.It is also found that the activity of anti-B antibody enhanced by the stimulation of deactivated bacterium(bacterium coli O86) after infants took them.So we can conclude that some of bacterial composition plays an important role on the mechanism of the generation of natural antibody of ABO blood group system.Toll-like receptors(TLRs) which express at cell membrane are related to the process of microorganism recognition of immune system and have some homologies with drosophila protein.They can identify conservative molecular composition of specific microorganism(pathogen- associated molecular patterns,PAMPs),then they activate signal transduction pathway,induce inflammation reaction and promote the activation of antigen presenting cell,these processes result in the initiation of innate immune responses and acquired immune responses and they can determine the direction of acquired immune responses.Various types of microorganism composition can activate TLRs.TLR4 is the major receptor of lipopolysaccharide(LPS) of gram negative bacterium while TLR2 recognizes composition of cell wall of gram active bacterium, spirochaeta, mycoplasma and yeasts of eumycetes.Recent research have make great progress in the aspects of function and recognition mechanism and association with certain clinical diseases of TLRs.Objective: To research the disparity of antibody titers among anti-B antibody of blood group A, anti-A antibody of blood group B,anti-A antibody of blood group O and anti-B antibody of blood group O. To discuss the association between Toll-like Receptor-4 and Toll-like Receptor-2 Gene Polymorphisms and natural antibody titers of ABO blood group system of healthy population in Dalian.Methods: Detect the IgM anti-A and anti-B antibody titers of 1058 random blood donors(include 329 donors of blood group A,344 donors of blood group B and 385 donors of blood group O) respectively to discriminate the high and low levels of each blood group in this experimentation. Use SPSS16.0 to analyze the disparity of natural antibody titers of each blood group.The polymorphisms of TLR4 gene Asp299Gly and Thr399Ile and TLR2 gene Arg753Glu and Arg677Trp were genotyped in donors with low and high IgM anti-A/B antibody of each blood group by fragment length discrepant allele specific PCR(FLDAS-PCR).Results: The disparity of antibody titers among anti-B antibody of blood group A, anti-A antibody of blood group B and anti-A antibody of blood group O has no statistical significance(P=0.119);The disparity of antibody titers among anti-B antibody of blood group A, anti-A antibody of blood group B and anti-B antibody of blood group O has no statistical significance, too(P=0.153);The antibody titers of anti-A antibody of blood group O and anti-B antibody of blood group O have significant disparity (P=0.000).The mutant genotypes of the TLR4 gene Asp299Gly and Thr399Ile and TLR2 gene Arg753Glu and Arg677Trp were not found in both high and low antibody titers donors of each blood group.Conclusion: The antibody titers of anti-A antibody of blood group O and anti-B antibody of blood group O have significant disparity (P=0.000). The disparity of the other IgM antibody titers of ABO blood group system has no statistical significance.There are no TLRs gene polymorphisms in population of Dalian in China.