Evaluation of cytokine genetic polymorphism in patients with common variable immunodeficiency

Uvod: Česta varijabilna imunodeficijencija (CVID) je bolest heterogene kliničke slike koju odlikuju poremećena diferencijacija i maturacija B-ćelija uz nedovoljnu produkciju antitela. Pripada grupi retkih bolesti sa procenjenom prevalencijom od 1:25000 do 1:50000, ali je ujedno najčešća klinički relevantna primarna imunodeficijencija. Početak i tok bolesti su veoma varijabilni. U kliničkoj slici dominiraju ponavljane bakterijske infekcije, uz brojne inflamatorne, limfoproliferativne i autoimunske poremećaje, kod približno polovine pacijenata. Sporadični oblici CVID se najverovatnije nasleđuju poligeno, ali je opisano više monogenskih uzročnih mutacija koje se javljaju u malom procentu prevashodno familijarnih oblika CVID. Opisani su brojni imunološki poremećaji, ali uzrok nastanka bolesti je još uvek nepoznat. Nekoliko istraživača je pretpostavilo da poremećaj u produkciji citokina, među kojima su i TNF, IL-10, IL-6 i IFN-gama, ima ulogu u etiopatogenezi poremećaja. Ciljevi istraživanja: Testirati hipotezu da genski polimorfizmi TNF (−308G/A), IFNG (+874T/A), IL10 (−1082G/A, −819T/C i −592A/C), i IL6 (−174G/C) doprinose sklonosti ka javljanju CVID ili posebnih kliničkih manifestacija bolesti. Ispitati distribucije alela i genotipova polimorfizama u genima IL-10, IL-6 u populaciji zdravih ljudi u Srbiji i uporediti ih sa objavljenim podacima za druge populacije. Ispitati produkciju TNF, IL-10, IL-6 i IFN-gama kod pacijenata sa CVID u odnosu na zdrave kontrole, kao i korelaciju genotipa pacijenata sa nivoima citokina. Pacijenti i metode: Trideset pet pacijenata sa CVID genotipizirani su pomoću Taqman eseja radi analize izabranih polimorfizama u TNF, IL6, IL10, i IFNG, kao i 250 zdravih kontrola za polimorfizme u genima IL6 i IL10 za koje nisu postojali podaci u zdravoj populaciji Srbije. Za ispitivanje slaganja distribucija dobijenih frekvencija genotipova u populaciji sa očekivanim vrednostima po Hardy-Weinberg ravnoteži, primenjivan je 2 test. Genotipsko-fenotipska korelacija je vršena tako što su pacijenti podeljeni u tri klinička fenotipa: bronhiektazije, splenomegalija i autoimunske bolesti...Introduction: Common Variable Immunodeficiency (CVID) is a heterogeneous disease characterized by impaired B cell differentiation and maturation accompanied with the defective antibody production. It is a rare disease, with estimated prevalence 1 in 25000 to 1 in 50000, but also the most common clinically relevant primary immunodeficiency. Age of onset and course of the disease are highly variable. Recurrent bacterial infections are dominant in clinical presentation, with inflammatory, lymphoproliferative and autoimmune disorders present in almost half of the patients. Sporadic CVID has putative polygenic inheritance, but several monogenic mutations are found in small percentage of patients, mostly in familiar cases of CVID. Plethora of immunological abnormalities is described, but the cause of the disorder is still unknown. Several investigators addressed the possibility that disturbed cytokine production of TNF, IL-6, IFN-gamma and IL-10, among a variety of others, may be implicated in CVID. Aims of the investigation: The aim of this study was to test the hypothesis that gene polymorphisms involving TNF (−308G/A), IFNG (+874T/A), IL10 (−1082G/A, −819T/C and −592A/C), and IL6 (−174G/C) cytokine genes might contribute to susceptibility to CVID or its clinical manifestations. In addition, we wanted to determine allele and genotype frequencies in the polymorphisms of the genes coding IL-10 and IL-6 in healthy Serbian population in order to compare them with the same data from other populations. Besides, the aim was to investigate TNF, IL-10, IL-6 and IFN-gamma cytokine production in the CVID patients related to healthy persons in control group, as well as to correlate the genotype of the patients with the cytokine production. Patients and methods: Thirty five patients with CVID were genotyped for indicated single nucleotide polymorphisms (SNP) in TNF, IL6, IFNG and IL10 using TaqMan-based assays, as well as 250 healthy controls for the SNPs in IL6 and IL10 which were unknown in healthy Serbian population. Hardy-Weinberg equilibrium for obtained data were tested using 2 test. In order to perform genotype-phenotype correlation, all patients were divided into three groups of distinct clinical phenotypes: bronchiectasis, splenomegaly and autoimmune diseases..