Effect of all-trans retinoic acid [ATRA] on viability, proliferation, activation and lineage-specific transcription factors of CD4+ T cells

All-trans retinoic acid [ATRA], as an active metabolite of vitamin A, has been shown to affect immune cells. This study was performed to evaluate the effect of ATRA on viability, proliferation, activation and lineage-specific transcription factors of CD4+ T cells. CD4+ T cells were separated from heparinized blood of healthy donors and were cultured in conditions, some with, some without ATRA. Viability was assessed by PI flowcytometry and proliferation was measured by MTT assay. CD69 expression was determined by flowcytometry as a measure of cell activation. Lineage-specific transcription factors [FOXP3, RORgammat and T-bet] were examined by intracellular staining and flowcytometry. High doses of ATRA [0.1-1 mM] caused extensive cell death in both PBMCs and CD4+ T cells. Doses of ATRA equal to or lower than 10 microM did not adversely affect cell viability and proliferation in comparison to culture medium without ATRA. Doses of ATRA between 10 microM and InM significantly increased cell activation when compared to culture medium without ATRA. ATRA could increase FOXP3+ and also FOXP3+RORgammat+ T cells while it decreased RORgammat+ and T-bet+ T cells. This study showed that doses of ATRA up to 10 microM are safe when using with CD4+ T cells in terms of cell viability, proliferation and activation. We could also show that ATRA diverts the human immune response in neutral conditions [without adding polarizing cytokines] by increasing FOXP3+ cells and decreasing RORgammat+ cells. ATRA could be regarded as a potential therapy in inflammatory conditions and autoimmunities

Association of HLA class II alleles with childhood asthma and total IgE levels

Asthma is a complex and multifactorial disorder. Several studies have reported association between different HLA- DQB1 and HLA- DRB1 alleles and allergic asthma. The aim of the present study was to investigate the association of HLA-class II alleles and haplotypes, with total serum IgE and the results of the skin prick test in Iranian children with allergic asthma. A total of 112 patients with allergic asthma symptoms [75 males and 37 females] were selected randomly from the pediatric hospital. In some patients total serum IgE and prick test were determined. Data of this study shows that HLA-DRB1*12 significantly increased in asthmatic patients [4.5% vs. 0%, P-value=0.04]. HLA-DQB1*0603 and 0604 alleles were significantly higher in asthmatics than those in normal controls [10% vs. 0%, P-value= 0.0001; and 9.3% vs. 3.7%, P-value= 0.04, respectively]. The statistical significance was relinquished after p value correction for all alleles except for HLA-DQB1*0602 [Pc=0.03] and HLA-DQB1*0603 [Pc=0.0015]. Conversely, HLA-DQB1*0501 and 0602 were decreased in asthmatics compared to normal controls [7.5% vs. 13.5%, P-value= 0.05; and 4% vs. 12.5%, P-value= 0.002, respectively]. The mean of total IgE in patients was 483 IU, and it was significantly high about 1140 IU in asthmatic patients with positive skin prick test to house dust. The most frequent alleles in asthmatic patients with the total IgE>200 IU/mL were HLA-DRB1*11and 1401, HLA-DQA1*0505, HLA-DQB1*0301 and in patients with total IgE<200 IU/mL were HLA-DRB1*0301, 07 and 1301, HLADQA1*0201 and 0301, HLA-DQB1*0201. These data suggests that HLA-DRB1, DQA1 and DQB1 alleles and haplotypes might be implicated in susceptibility to allergy and asthma and serum IgE production. As asthma and atopy are multifactorial disorders, probably HLA genes are involved in the regulation of immune specific responses to common allergen

HLA class II allele and haplotype frequencies in Iranian patients with leukemia

Previous studies demonstrated significant differences in a number of HLA allele frequencies in leukemia patients and normal subjects. In this study, we have analyzed HLA class II alleles and haplotypes in 110 leukemia patients [60 acute myelogenous leukemia "AML", 50 chronic myelogenous leukemia"CML"] and 180 unrelated normal subjects. Blood samples were collected from all of the patients and control subjects. DNA was extracted by salting out method and HLA typing was performed using PCR-SSP method. Significant positive association with AML was obtained for HLA-DRB1*11allele [35% vs. 24.7%, P=0.033]. Two alleles including HLA-DRB4 and-DQB1*0303 were significantly less frequent in AML patients than in controls. HLA-DQB1*0303 allele was never observed in CML patients compared with allele frequency in controls [4.2%]. According to haplotype analysis, HLA-DRB1*0101/DQA1*0104/-DQB1*0501 frequencies were significantly higher and-DRB1*16/-DQA1*01021/-DQB1*0501 frequencies were significantly lower in CML patients than in controls .In conclusion it is suggested that HLA-DRB1*16 allele and HLA-DRB1*15/-DQA1*0103/-DQB1*06011 and-DRB1*16/-DQA1*01021/-DQB1*0501 haplotypes predispose individuals to AML and HLA-DRB4 allele predispose to CML. Future studies are needed to confirm these results and establish the role of these associations in AML and CML

Th1 and Th2 cytokine gene polymorphism in Iranian patients with chronic myelogenous leukemia

Bakground: lt has been hypothesized that genetic factors other than histocompatibility disparity may play a role in predisposition to developing Chronic Myelogenous Leukemia [CML]. In this regard, Thl and Th2 cytokines and their gene polymorphism seems to be important. Overall expression and secretion of cytokines is dependent, at least in part, on genetic polymorphism [nucleotide variations] within the promoter region or other regulatory sequences of cytokine genes. The majority of polymorphisms described are single nucleotide polymorphism [SNPs]. The objective of this study was to analyze the genetic profile of Thl and Th2 cytokines in 30 Iranian patients with CML and 40 healthy subjects

Methods: In the patients and control subjects, the allelic and genotype frequencies were determined for the cytokine genes. All typing were performed by PCR-SSP assay. Allele and genotype frequencies were calculated and compared with those of normal controls

Results: The results showed that the most frequent alleles in our patients were TGF-3 TG/TG, IL-4 T at position -1089, C at position -590, T at position -33 and IL-10 A at position -1082. Whereas the following alleles - TGF-3 CG/CG and IL-10 C at position -592 - were seen in much lower frequencies

Conclusion: In conclusion, it could be suggested that the frequency of high producing TGF-3 alleles and low producing IL-4 and IL-10 alleles in the CML patients is higher than the normal subjects

Evaluation of Anti- HLA Class I antibodies in chronic rejection of kidney transplantation

Studies have shown that patients who do not produce donor specific and / or panel reactive anti-HLA antibodies have a longer graft survival. The purpose of this study was to evaluate the posttransplant humoral immune response towards HLA-class I antigens and the measurement of the serum creatinine levels which are used in monitoring posttransplant function of kidney. Serum samples from 132 renal transplant recipients were screened for preformed anti-HLA class I panel reactive antibodies [PRA] by means of microlymphocytotoxicity assay. The results revealed the presence of PRA in 26 [19.7%] out of 132 transplanted patients. Graft function was evaluated by measurement of serum creatinine levels which revealed the mean of 1.75 mg/di [SD: 1.08]. Because of clinical significance of presence of different PRA amounts [>10%, > 20% and >50% of panel reactivity] in patients, correlation with kidney function status was analyzed. The obtained data highlighted a higher presence of serum creatinine levels in PRA-positive patients compared to negative patients [P<0.01]. These results [and further studies for class II, ...] can be used to implement new therapeutic strategies to curtail post transplant alloantibodies production and better allografts survival

Interferon-gamma gene polymorphism in Iranian patients with multiple sclerosis

Interferon- gamma [IFN- gamma] is an important immune regulator and inflammatory cytokine which is implicated in the pathogenesis of multiple sclerosis [MS]. A single nucleotide polymorphism, T to A, at position +874 in the first intron has previously been shown. This polymorphism is associated with IFN- gamma production level. To study the effect of this polymorphism on susceptibility to multiple sclerosis, we screened genomic DNA samples from clinically definite MS patients and their unaffected first-degree relatives as controls, using sequence-specific primers [PCR-SSP]. The results indicated that MS patients showed a lower TT [21.2% vs. 30.3%] and higher AA [21.2% vs. 12.1%] genotypes compared to controls, although there were statistically no differences in the IFN- gamma genotype distribution between these two groups. Thus, our data indicate that there is no association between IFN- gamma +874 polymorphism and MS susceptibility or severity of the disease