Question

1.

Billy continued to remain asymptomatic even though he eventually only had around 30% engrament of his sister's bone marrow stem cells (as judged from the proportions of the T cells). Why is full engraftment is not necessary in patients with IPEX?

2. Why did Billy's diarrhea improve when he was being prepared for transplantation?

3. Intravenous immunoglobulin has been used to treat IPEX . How might that be an effective therapy?

4. The occurrence of colitis in IPEX suggests that Treg cells may be implicated in it's parthenogenesis and that might be used therapeutically in more common forms of colitis. Is there experimental data to support this claim?

5. What other gene mutations can be give rise to a clinical picture similar to IPEX?

Answer 1

1) Immune dysregulation , polyendocrinopathy enteropathy X linked syndrome (IPEX) is an inherited syndrome of early onset systemic autoimmunityand the prototype of immune disregulatory disorder. It caused by mutation in FOXP3 gene encoding a key transcription factor for natural regulatory T cell ( nTreg). Complete donor engrafment in all hematopoietic lineage may not be necessary because the prefrential engrafment of donor Treg cell seems to be sufficient to control the disease.