Effects of metformin on autoimmune immunoglobins and interferon-γ in patients with early diagnosed pemphigus vulgaris: a prospective clinical trial

The management of pemphigus vulgaris (PV) is challenging. This study aimed to evaluate the immunomodulating effects of metformin on PV. The study was conducted in two phases: in the first phase, patients received routine first-line treatment (prednisolone plus azathioprine) for 2 months, then in the second phase, metformin was added to this regimen for another 2 months. After addition of metformin to the first-line medications, significant reductions were seen in serum IgG1 (reduced from 534.92 ± 134.83 mg/dL to 481.58 ± 130.46 mg/dL, P < 0.001), IgG4 (51.83 ± 27.26 mg/dL to 44.50 ± 26.05 mg/dL, P < 0.001) and interferon-γ (277.99 ± 108.71 pg/mL to 45.05 ± 17.080 pg/mL, P = 0.03) concentrations. The suppressant effect of metformin was greatest on IgG4 (coefficient of variation 1.28), the dominant subclass of IgG involved in PV. Metformin could have immunomodulating effects on PV with controlling effects on steroid complications.

HLA-DRB1*01:01, but not HLA-DRB1:1503 or HLA-DRB1*11, is associated with decreased inhibitor risk in Iranian hemophilia A patients

BACKGROUND/OBJECTIVE

Hemophilia A is a genetic disorder through which patients suffer from recurrent bleeding. This can be caused by a defect in human plasma coagulation factor VIII. High incidence of FVIII inhibitors in some severe hemophilia A patients after FVIII therapy is a considerable complication. Determination of good predictive factors can improve the safety of this treatment. HLA-II have been shown as a predictive element for inhibitor development. The goal of this study is to determine the association between HLA-DRB1*15:03, HLA-DRB1*11 and HLA-DRB1*01:01 alleles and FVIII inhibitors in severe hemophilia A patients in Iran.

MATERIALS/METHODS

HLA-DRB1 genotyping was performed using Multiplex sequences Specific Primers (PCR-SSP) in two groups of severe hemophilia A patients comprising 51 and 50 individuals with and without FVIII inhibitors respectively. The levels of inhibitor were determined through Nijmegen-modified Bethesda assay. HLA-DRB1 allele frequencies were compared between groups by using multiple logistic regression models.

RESULTS

HLA-DRB1*01:01 allele frequency was significantly higher in patients without inhibitor OR_adj: 2.7 (95%CI: 1.08, 6.97; P = 0.034). There wasn't any statistically significant difference in HLA-DRB1*11 allele frequency between groups OR_adj: 0.7 (95%CI: 0.27, 1.82; P = 0.47). There was no connection between HLA-DRB1*15:03 and inhibitor development OR_adj: 0.94 (95%CI: 0.38, 2.35; P = 0.94).

CONCLUSION

An association between HLA-DRB1*01:01 and paucity of FVIII inhibitor showed that this allele has probably a protective effect in severe hemophilia A patients in Iran. Determination of the predictive and protective alleles are beneficial in pre-treatment activities and decrease the risk of unsuccessful therapy with FVIII in each population.

Effect of Ramadan fasting on glycemic control in patients with Type 2 diabetes

BACKGROUND

Although Muslim patients with Type 2 diabetes may be exempt from fasting during Ramadan for medical reasons, a high proportion of them fast.

AIM

To investigate the association between Ramadan fasting and glycemic control in patients with Type 2 diabetes.

SUBJECTS AND METHODS

A prospective cohort clinical trial was designed. Eighty-eight patients with Type 2 diabetes (45 male, 43 female, age 51±10 yr) who opted to fast for at least 10 days during the month of Ramadan were recruited. Fasting blood samples were taken at the beginning and end of Ramadan, and 1 month after Ramadan, to assess fasting blood glucose (FBG), fasting insulin, full blood count, glycated hemoglobin (HbA(1c)) and fasting lipid profile. Insulin resistance was estimated using the homeostatic model assessment. Anthropometrics and blood pressure were also measured.

RESULTS

There was a significant deterioration in FBG and HbA(1c) (p=0.002 and p≤0.001, respectively) and significant improvements in HDL and LDL cholesterol and body mass index after Ramadan (p<0.001). Interestingly, HbA(1c) showed a reduction 1 month after Ramadan (9.4±2% at the end of Ramadan vs 8.4±2.5% 1 month after Ramadan; p<0.001).

CONCLUSION

Results from this study showed that fasting during Ramadan deteriorated the glycemic control in Type 2 diabetes patients. This was more evident in patients using oral hypoglycemic medication than diet- controlled patients. However, Ramadan fasting had small positive effects on lipid profile and body weight.

The polymorphism of human leucocyte antigen-G gene in a healthy population of Iran

Human leucocyte antigen-G (HLA-G) is a non-classical HLA class I molecule that unlike the classical HLA, has low polymorphism. This molecule, initially, found on invasive trophoblast cells and is postulated to have mediatory role in maternal-fetal interface. So far 43 alleles of HLA-G gene have been found. Studies on alleles of HLA-G gene could be useful in understanding the genetic variants of HLA-G alleles in Iranian population. The goal of this research was to determine the polymorphism of HLA-G gene in a healthy population of Iran. Genomic DNA was isolated from the whole blood of 102 randomly selected, healthy, unrelated Iranian individuals using salting-out technique followed by polymerase chain reaction (PCR) amplification of the exons 2 and 3 of HLA-G gene. For the performance of PCR-restriction fragment length polymorphism method, the PCR products were digested with several restriction enzymes and the resulted fragments were analysed using gel electrophoresis. The obtained results indicated nine alleles of HLA-G in Iranian individuals including G*01011 (4%), G*01012 (29.86%), G*01013 (10.8%), G*01015 (1.47%), G*01017 (1.96%), G*01018 (2.45%), G*01041 (29.4%), G*01043 (1.96%) and the null allele G* 0105N (18.1%). According to this study, in the Iranian subjects the most incident alleles were G*01012 and G*01041. The results for the frequency of G*01012 showed some similarity with Caucasians (36.3%).

Association of aplastic anaemia and Fanconi's disease with HLA-DRB1 alleles

One of the most fascinating areas of research within the field of histocompatibility at present time concerns an observation that a major human histocompatibility system, human leucocyte antigen (HLA), is deeply involved in the development of a great number of diseases. Major histocompatibility complex is the most polymorphic system in the genome of different species. Recognition of HLA alleles could be useful in transplantation and disease studies. Genetic construct of HLA DRB1 was studied in Iranian normal populations and patients with aplastic anaemia and Fanconi's disease. DNA was extracted from the whole blood of 466 normal, 35 aplastic anaemia and 10 Fanconi's individuals. Then DRB1 gene polymorphism was studied by polymerase chain reaction-sequence-specific primer method. The HLA DRB1 gene analysis showed increase of DRB1*07 in aplastic anaemia patients compared to normal population (P = 0.02). According to this study, the frequency of DRB1*07 in normal individuals was 8.3, and in aplastic anaemia patients, 15.7%. Additionally, the frequency of DRB1*04 in normal, aplastic anaemia and Fanconi's individuals was 10, 5.7 and 20%, respectively. Our results of investigation showed correlation between some HLA alleles with the studied diseases. We reported the frequency of various DR types in aplastic and Fanconi's patients. This study could imply the possible role of HLA-DRB1*07 in the incidence of aplastic anaemia. Moreover, the frequency of DRB1*04, DRB1*03 and DRB1*15 alleles showed intermediate correlation with Fanconi's anaemia.

Human antibodies from phage libraries: neutralizing activity against human immunodeficiency virus type 1 equally improved after expression as Fab and IgG in mammalian cells

Human antibodies against HIV-1 have been sought to study neutralization events on the molecular level, and for possible use in passive immune intervention. The development of phage display techniques has opened the possibility of rapidly generating human monoclonal antibodies with desired specificities. We and others have isolated human HIV-1 neutralizing antibody fragments using this technique. Bacterial expression of isolated clones does, however, differ broadly both in expression levels and functional activity. In addition, intact IgG cannot be expressed in bacteria. By transferring the genes of isolated Fab clones to a mammalian expression system we could perform a comparison of functional activity between Fab expressed in bacterial and mammalian cells, as well as Fab and whole IgG. Fab fragments expressed in mammalian cells showed increased virus neutralizing activity compared to the same Fab clones expressed in Escherichia coli, underlining the inefficiency of procaryotic expression. No difference in HIV-1 neutralizing capacity was detected between monovalent (Fab) and divalent (whole antibody) reagents expressed in CHO cells. Thus, bivalency does not always confer improved neutralization efficacy.