CD28 and autoimmune thrombocytopenic purpura: Thereafter, combined analysis under the codominant model by multivariate logistic regression analysis revealed that the heterozygous genotypes of TIM3 rs10515746 and CD28 rs1980422 played a significant role in increased risk of ITP (OR = 3.509, 95% CI = 1.128–10.914, p = 0.03; OR = 1.788, 95% CI = 1.178–2.713, p = 0.006, respectively, Table 4).