Increased expression of CD40 and CD401 in acute coronary syndrome patients: association with genetic variants in western Mexican population

Abstract Acute coronary syndrome (ACS) belongs to the clinical entities characterized by obstruction of a coronary artery. In its etiology, inflammation contributes significantly trough the activation of immune cells by co-stimulatory molecules as CD40 and CD40L. The purpose of this work was to explore the changes of mRNA and circulating soluble levels of CD40-CD40L in ACS patients and association with genetic variants in a western Mexican population. 320 ACS patients and 300 individuals with similar age than cases without ischemic cardiopathy were recruited. Genotype determination was made using TaqMan SNP genotyping assays. CD40 and CD40L mRNA expression in whole blood samples were quantified using TaqMan Gene Expression Assays. Soluble levels were measured in plasma by enzyme-linked immunosorbent assay. We did not find evidence of association between on CD40 (rs1883832, rs4810485 and rs11086998) and CD40L (rs3092952 and rs3092920) genetic variants and susceptibility to ACS nor changes in their mRNA expression (p>0.05), although rs1883832 and rs4810485 affected significantly sCD40 circulating levels (p=0.005; p=0.015, respectively). Circulating soluble levels were higher in ACS patients; specifically sCD40L was higher in male patients with unstable angina compared to female patients (p=0.016). Our results showed genetic variants affect soluble levels of CD40 although the CD40 and CD40L polymorphisms are not associated with susceptibility to ACS in western Mexican population. CD40L mRNA expression, sCD40 and sCD40L plasma levels were higher in ACS patients even when they are under pharmacological treatment, which suggests an active role of the CD40-CD40L system in the immunopathogenesis of acute coronary syndrome.