The potential association of tumor necrosis factor-βeta (252 G/A) cytokine gene polymorphism with immune thrombocytopenic purpura among Egyptian children

Role of interleukin 4 (IL4) and interleukin 6 (IL6) in the pathogenesis and prognosis of childhood primary immune thrombocytopenia

Immune thrombocytopenia (ITP) is an autoimmune disease characterized by the breakdown of immune tolerance. Impairment of the cellular immunity is primarily evaluated by the levels of the cytokines which can help in predicting the course of ITP. We aimed to assess the levels of IL4 and IL6 in children with ITP and evaluate their role in the pathogenesis and prognosis of this disease. A prospective cohort study was carried on 60 children (15 patients with newly diagnosed ITP, 15 patients with persistent ITP, 15 patients with chronic ITP and 15 healthy children as a control group). Serum IL-4 and serum IL-6 were measured using Human IL-4 and IL-6 ELISA kit in patients and controls. Patients with newly diagnosed and persistent ITP had significantly higher levels of IL4 and IL6 compared to patients with chronic ITP and healthy controls (p < 0.001). The mean serum level of IL4 was 762.0, 741.0, 364.6 and 436.8 pg/ml, and the mean serum level of IL6 was 178.5, 164.4, 57.9 and 88.4 pg/ml for patients with newly diagnosed, persistent, chronic ITP and healthy controls respectively. Serum IL-4 was significantly higher in patients who achieved remission than those who did not improve on first line therapy.

CONCLUSION

Serum IL-4 and IL-6 may have a role in the pathogenesis of primary ITP. IL-4 seems to be a good predictor to treatment response.

WHAT IS KNOWN

• There is a delicate balance of specific cytokine levels in immune thrombocytopenia, which has an important role in the immune system and is known to be deregulated in autoimmune diseases. changes in IL-4 and IL-6 might be involved in the pathogenesis of newly diagnosed ITP in both paediatric and adult patients. • We conducted this research study to measure the serum level of IL-4 and IL-6, in newly diagnosed, persistent and chronic ITP patients and study their relation to disease pathogenesis as well as patient's outcome.

WHAT IS NEW

• We found that IL4 seems to be a good predictor to treatment response and it was a very interesting observation in our study, and to the best of our knowledge, there is no published data about this finding.

Combined tumor necrosis factor-α (-308 G/A) and tumor necrosis factor-β (+ 252 A/G) nucleotide polymorphisms and chronicity in Egyptian children with immune thrombocytopenia

BACKGROUND

Primary immune thrombocytopenia (ITP) is a common autoimmune disorder. Secretion of TNF-α, TNF-β and IFN-γ plays a major role in the pathogenesis of ITP.

OBJECTIVE

This cross-sectional study aimed to detect TNF-α (-308 G/A) and TNF-β (+ 252 A/G) gene polymorphism in a cohort of Egyptian children with chronic ITP (cITP) to clarify their possible association with progression to chronic disease.

METHODS

The study included 80 Egyptian cITP patients and 100 unrelated age- and sex-matched controls. Genotyping was performed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

RESULTS

Patients with TNF-α homozygous (A/A) genotype had significantly higher mean age, longer disease duration and lower platelet counts (p values 0.005, 0.024 and 0.008, respectively). TNF-α wild (G/G) genotype was significantly more frequent among responders (p = 0.049). Complete response was more frequent among wild (A/A) TNF-β genotype patients (p = 0.011), and platelet count was significantly lower among homozygous (G/G) genotype (p = 0.018) patients. Combined polymorphisms were strongly associated with susceptibility to chronic ITP.

CONCLUSION

Homozygosity in either gene might contribute to a worse course of disease, increased severity and poor response to therapy. Patients expressing combined polymorphisms are more prone to progression to chronic disease, severe thrombocytopenia and longer disease duration.

Effect of Cytokine Gene Polymorphisms on Eltrombopag Reactivity in Japanese Patients with Immune Thrombocytopenia

BACKGROUND

Immune thrombocytopenic purpura (ITP) is an autoimmune disease characterized by low platelet counts resulting from antiplatelet autoantibodies. Analysis of polymorphisms in cytokine-encoding genes is important for understanding the pathophysiology of ITP and selecting appropriate treatments. We investigated associations between polymorphisms in cytokine-encoding genes and responses to therapy in Japanese patients with ITP.

METHODS

The participants in this study comprised 153 patients with ITP and 70 healthy controls. We extracted data on sex, age, platelet counts, bleeding symptoms, and therapeutic responses, including those to prednisolone (PSL) and eltrombopag. Genomic DNA was isolated from peripheral blood and polymorphisms in TNF-α, IL-10, TGF-β1, and IFN-γ genes were analyzed using the PCR-SSP method.

RESULTS

Our results showed that the TGF-β1 +869 C/C genotype might be related to ITP in Japanese patients. The IL-10 -592 C/C and A/A, -819 C/C and T/T, and -1082, -819, -592 ATA/ATA genotypes might be associated with reactivity to PSL. Furthermore, the IL-10 -592 C/A -819 C/T genotypes, IL-10 ACC/ATA genotype, and TGF-β1 +869 T/T and T/C genotypes might be linked to the response to eltrombopag.

CONCLUSION

Our results indicate that analysis of polymorphisms in cytokine-encoding genes could aid in understanding PSL and eltrombopag responsiveness in Japanese patients with ITP.