MethodsFollowing informed written consent, peripheral blood was drawn from patients with ITP requiring first line steroid treatment registered at University Hospitals Bristol, UK. Of these, 22 demonstrated complete response to steroid treatment with platelet count rising >100 x109/L within 2 weeks of treatment (steroid sensitive, SS) and 10 were refractory to treatment with a platelet count remaining <30x109/L following 2 weeks of treatment (steroid resistant, SR). Blood samples from patients with non-infectious intraocular inflammation (uveitis: an autoimmune condition treated with steroids) were also taken as a control disease cohort (SS n=14, SR n=21). CD4+ T cells were isolated and activated via the T cell receptor with anti-CD3/anti-CD28 T cell activation beads in the presence or absence of the synthetic GC Dexamethasone (Dex). After 96 hours of culture, intracellular cytokine expression of IL-10 and IL-17 was examined by multiparameter flow cytometry.
ResultsCD4+ T cells isolated from clinically SR ITP patients showed higher expression of IL-17 and lower expression of IL-10, resulting in a reduced IL-10:IL-17 ratio when activated with anti-CD3/anti-CD28 beads in the presence of Dex (Figure 1A), compared to clinically SS patients (p=0.0015). Similar results were found in patients with uveitis (aCD3/aCD28+Dex SS vs SR p=0.0044), corroborating this finding (Figure 1B).
ConclusionThese data suggest that CD4+ T cells are important mediators of clinical response to steroid treatment and that the cytokine signature of CD4+ T cells may form the basis of a laboratory biomarker to help predict clinical response to GC treatment for patients with ITP as well as those with other autoimmune conditions. This would aid clinical decisions for patients, potentially maximizing treatment efficacy while minimizing side-effects.
|Title of host publication||Blood|
|Publisher||American Society of Hematology|
|Number of pages||1|
|Publication status||Published - 7 Dec 2017|
- biological markers
- thrombocytopenia due to immune destruction
- inosine triphosphate
- adverse effects