ABSTRACT
Objective To investigate the association between genetic polymorphisms of Dectin-2 and pulmonary cryptococcosis.Methods A total of 134 non-human immunodeficiency virus (HIV)patients with pulmonary cryptococcosis and 464 healthy controls were included in this case control study.The peripheral leucocyte DNA was extracted and genotyping was performed by multiplex SNaPshot technology.The single nucleotide polymorphism (SNP)of rs11045418 located at 5′-flanking locus of Dectin-2 gene was genotyped.Patients without predisposing conditions were compared independently.The differences of gene polymorphism distributions compared between pulmonary patients and healthy control, and between patients without predisposing conditions and healthy control.All data were analyzed withχ2 tests.Results Among the total 134 patients,82 patients had no predisposing factors.Thirty two patients met the proven diagnosis criteria and 102 patients were probable pulmonary cryptococcosis.According to the site of infection, 72 patients had local infection in lungs and 62 patients had disseminated cryptococcosis.Three samples failed in genotyping,one of which was a patient without predisposing factor.Compared with the control group,there was a trend of increasing proportion of heterozygote rs11045418 CT in the 131 pulmonary cryptococcosis patients (59% vs 50%,P =0.069,OR=1.44,95%CI :0.97-2.13),and the heterozygote was significantly increased in 81 patients without predisposing conditions(64% vs 50%,P =0.017,OR= 1 .82,95 %CI :1 .11 -2.95 ).No significant difference of genotype distribution was found between the local and disseminated infection patients.Conclusion Our study shows that rs11045418 CT heterozygote in Dectin-2 is associated with the susceptibility of pulmonary cyrptococcosis among non-HIV-infected Chinese patients,which indicated that the change of Dectin-2 receptor may play a role in the pathogenesis of pulmonary cyrptococcosis.
ABSTRACT
Objective To describe the distributions of FCGR polymorphisms in human immunodeficiency virus (HIV)-uninfected patients with cryptococcosis,and to investigate the association of FCGR polymorphisms with the susceptibility to cryptococcosis.Methods The distributions of the four functional polymorphisms,including FCGR2A 131H/R,FCGR3A 158F/V,FCGR3B NA1/NA2,and FCGR2B 232I/T were compared between 198 cryptococcosis patients and 190 healthy controls.The polymorphisms distribution patterns were also compared between patients with central nervous system (CNS) infection and those without CNS infection.Genotyping of eight single nucleotide polymorphism (SNP) in FCGR were performed by multiplex SNaPshot technology using DNA extracted from blood samples.The comparison between patients and controls was performed by chi square test or Fisher exact test.Results Compared to healthy controls,the frequency of FCGR2B 232I/I increased (65％ vs 53％,x2 =4.27,P=0.039,OR=1.652,95％CI:1.02-2.67) and that of FCGR2B 232I/T decreased (27％ vs 40％,x2 =5.77,P=0.016.OR=0.542,95％CI:0.33-0.90) in patients with cryptococcal meningitis.Among immunocompetent patients,the frequency of FCGR2B 232I/I was also over-presented (69％ vs 53％,x2=4.53,P =0.033,OR=1.958,95％CI:1.05-3.66) and the FCGR2B 232I/T genotype was also less frequently observed (24％ vs 40％,x2=5.14,P=0.023,OR=0.467,95％CI:0.24-0.91) compared to healthy controls.There were 117 cases with CNS infection and 81 non-CNS infection cases.The genotype of FCGR2A 131R/Rwas over-presented (19％ vs 6％,x2 =6.48,P=0.011,OR=3.52,95％CI:1.27-9.73) and the FCGR2B 232I/T genotype was under-presented (27 ％ vs 46 ％,x2 =7.56,P =0.006,OR=0.431,95％CI:0.24-0.79) in patients with CNS infection compared with those without CNS infection.Furthermore,the frequency of FCGR2B 232I/I genotypes increased (69％ vs47％,x2 =5.47,P=0.019,OR=2.479,95％CI:1.15-5.34) and the frequency of FCGR2B 232I/T decreased (24％ vs 51％,x2 =8.66,P=0.003,OR=0.307,95％CI:0.14-0.68) in immunocompetent patients with CNS infection compared with those without CNS infection.Conclusions FCGR2A 131H/R and FCGR2B 232I/T are associated with the susceptibility to cryptococcal CNS infection,which suggests that FcγRⅡA and FcγRⅡB may contribute to the pathogenesis of cryptococcosis.