Abstract-Recent findings suggest that inflammation plays a role in atherosclerosis and its acute complications. Cellular response in infections with Gram-negative bacteria is mediated by bacterial lipopolysaccharide (LPS), which activates monocytes to expression of cytokines, growth factors, and procoagulatory factors via LPS receptor CD14. Endothelial cells and smooth muscle cells are stimulated by a complex of LPS and soluble CD14. In this study, LPS receptor CD14 was analyzed to find genetic variants and check them for an association with coronary artery disease or myocardial infarction (MI). When screening the CD14 gene by single-strand conformation polymorphism analysis, a promoter polymorphism was detected and confirmed as a T-to-C exchange at position Ϫ159. We determined the genotypes of 2228 men who had undergone coronary angiography for diagnostic purposes. Within the total study group there was no significant association of either genotype with MI or coronary artery disease. However, in a subgroup with low coronary risk (normotensive nonsmokers), a relative risk for MI in probands homozygous for the T allele could be evaluated (OR, 1.6; 95% CI, 1.0 to 2.4; PϽ0.05). The association was even stronger in low-risk patients older than 62 years (OR, 3.8; 95% CI, 1.6 to 9.0; PϽ0.01). In conclusion, we describe a new CD14 promoter polymorphism that is associated with MI, especially in older patients with a low atherosclerotic risk profile. (Arterioscler Thromb Vasc Biol. 1999;19:932-938.)Key Words: CD14 Ⅲ genetics Ⅲ coronary disease Ⅲ myocardial infarction Ⅲ risk factors C D14 is a leucine-rich 55-kDa glycoprotein that is expressed in considerable amounts by mature monocytes, macrophages, and activated neutrophil granulocytes. 1 In these cells CD14 is known as a surface marker, being glycosylphosphatidylinositol anchored in the cell membrane (mCD14). 2 In addition, soluble CD14 (sCD14) can be found in serum where 2 major isoforms coexist, differing in molecular weight. 3 CD14 serves as receptor for bacterial lipopolysaccharide (LPS, endotoxin) and mediates cell activation by LPS. 4 The receptor-ligand interaction depends on a serum protein, LPS-binding protein, which complexes LPS and facilitates binding to mCD14 or sCD14. 5 Endothelial cells 6 and smooth muscle cells 7 are activated via sCD14, lacking their own membranous protein and CD14 mRNA. 7 In addition, they are activated indirectly by cytokines from LPSstimulated monocytes. 8 Endotoxin-activated monocytes produce proinflammatory cytokines such as tumor necrosis factor-␣, interleukin-1 and interleukin-6, and growth factors. 9 In stimulated endothelial cells, expression of endothelial leukocyte adhesion molecule-1, 10 intercellular adhesion molecule-1, 11 and vascular cell adhesion molecule-1 12 is induced, accompanying cell adhesion to endothelium. 12 LPS increases the levels of LDL and VLDL and supports the oxidation of LDL; HDL levels are decreased. 13 It stimulates smooth muscle cell proliferation and migration by release of platelet-derived growth f...

The diallelic human platelet alloantigen systems 1-5 have been found to result from single base pair substitutions in the encoding genes of platelet membrane glycoproteins IIIa, Ib, IIb and Ia. This is the basis of DNA methods for determination of platelet alloantigens. In this study, 98 blood donors were typed in the HPA-1, 2, 3 systems and, for the first time, in the HPA-5 system. Serologically obtained data (MAIPA and platelet agglutination) were compared with results from analysis of restriction fragment length polymorphisms (RFLP). Discordances were found in the HPA-2 and 3 systems and can be ascribed to false typing results in both the serological and genomic methods. In the HPA-1, 2 and 5 systems, all samples were typed correctly with RFLP analysis. Serologically, two donors were falsely typed positive with anti-HPA-2b in platelet agglutination and one donor with anti-HPA-3a in MAIPA assay. In the HPA-3 system, another four donors were misinterpreted to be HPA-3a negative in RFLP analysis. Possible technical problems in PCR-RFLP-typing are discussed and another strategy of HPA-1 typing using the restriction enzyme Scr FI is evaluated.

SummaryAlloimmunization against the human platelet alloantigen system Br (HPA-5) is the second most common cause of neonatal alloimmune thrombocytopenia (NAIT) in Caucasian populations. We have recently shown that a single base polymorphism at position 1648 on platelet mRNA coding for GPIa results in an aminoacid substitution at position 505 on the mature GPIa which is associated with the two serological defined Br phenotypes.Since DNA-typing of platelet alloantigens offers possibilities for useful clinical applications, we designed genomic DNA-based restriction fragment length polymorphism (RFLP) typing for Br alloantigens. To establish this technique we analyzed the genomic organization of GPIa adjacent to the polymorphic base. Using the polymerase chain reaction (PCR) of blood cell DNA we have identified two introns (approximately 1.7 and 1.9 kb) flanking a 144 bp coding sequence of the GPIa gene encompassing the polymorphic base 1648. Based on the in- tron sequence, a PCR primer was constructed to amplify a 274 bp fragment which was used for allele-specific RFLP to determine the Br genotypes. The results of RFLP analysis using Mnll endonuclease obtained from 15 donors (2 Br37*, 2 Br^ and 11 Brb/b) correlate perfectly with serological typing by monoclonal antibody-specific immobilization of platelet antigens (MAIPA) assay.

Summary. Alloimmunization against platelet antigens is related to neonatal alloimmune thrombocytopenia and post‐transfusion purpura. Moreover, platelet‐specific alloantibodies, in addition to HLA‐specific antibodies, play a role in the state of refractoriness to platelet transfusions. Most platelet‐specific alloantigens have been assigned to platelet glycoproteins IIb/IIIa, Ib/IX and Ia/IIa. Data on antigen frequencies were first reported for Caucasians, but since then platelet glycoprotein polymorphisms have been reported for other populations, e.g. the Yuk alloantigens in Japanese. As information on the distribution of the recently described alloantigens is incomplete in Caucasians, this study was undertaken to provide reliable data on the PIA, Ko, Bak, Yuk and Br (HPA 1–5) alloantigens, of the ‘low‐frequency’ Sra and Vaa antigens and of the Naka isoantigen. In contrast to the frequencies determined in Oriental populations, all 964 individuals tested in this study were Yuka‐negative and all persons tested (n= 382) had Naka‐isoantigen‐positive platelets. A comparison of typing results shows that the recently described Siba‐alloantigen is identical with the Koa antigen.