Soluble Programmed Death 1 (PD-1) Is Decreased in Patients With Immune Thrombocytopenia (ITP)

Abstract

Immune thrombocytopenia (ITP) is an autoimmune disease characterized by dysregulation of T cells. Programmed death (PD) 1 and programmed death 1 ligand 1 (PD-L1) are cosignaling molecules, and the major role of the PD-1 pathway is the inhibition of self-reactive T cells and to protect against autoimmune diseases. We measured levels of serum soluble PD 1 (sPD-1) and serum soluble PD-L1 (sPD-L1) in 67 patients with ITP (24 newly diagnosed ITP [ndITP], 43 chronic ITP [cITP]) and 21 healthy controls (HCs). We determined decreased serum sPD-1 levels both in patients with ndITP and in patients with cITP when compared to HC. Moreover, there was a positive correlation between sPD-1 levels and platelet counts. The sPD-L1 levels were decreased in patients with ndITP when compared to patients with cITP. This is the first study investigating PD-1 signaling pathway in ITP. Decreased sPD-1 levels may have a role in ITP pathogenesis as without the inhibitory regulation of PD-1, sustained activation of T cells may cause inflammatory responses which is the case in ITP.

Numerical and functional defects in CD8+CD28− T‐suppressor lymphocytes from patients with primary immune thrombocytopenia

“…To further explore the reason for the impaired cell-tocell contact regulation, we also investigated the expressions of PDCD1 and ICOS on the CD8 + CD28 À surface using FACS. Although it was reported that PDCD1 mRNA expression in PBMCs and soluble PDCD1 in serum was decreased in ITP patients (Birtas Atesoglu et al, 2016;Zhong et al, 2016), we did not find any difference in PDCD1 expression on CD8 + CD28 À Ts cells between ITP patients and controls. This result suggested that PDCD1 might not be associated with the Ts defect in ITP patients.…”

WITHDRAWN: Decreased plasma sPD-1 level correlates with disease activity in systemic juvenile idiopathic arthritis patients

“…Plenty of studies have demonstrated that sPD-1 and sPD-L1 were involved in autoimmune disease, such as systemic lupus erythematosus (SLE) [13], autoimmune type 1 diabetes [14], Immune thrombocytopenia (ITP) [15] rheumatoid arthritis (RA) [16] and chronic hepatitis B [17], while few was reported on sJIA. Our previous study have reported decreased PD-1 on CD4 + T cell and reduced PD-L1 on mDC (myeloid dendritic cell) in active sJIA patients [18].…”

Soluble immune checkpoint molecules: Serum markers for cancer diagnosis and prognosis

“…Such blockade leads to restoration of T‐cell activity that can lead to enhancement of anti‐tumor immune responses. Although sPD‐1 is found in healthy individuals, its concentration increases in patients with autoimmune diseases . Interestingly, several studies have shown correlation between the levels of sPD‐1 in patient sera and cancer progression.…”

“…Although sPD-1 is found in healthy individuals, its concentration increases in patients with autoimmune diseases. [106][107][108] Interestingly, several studies have shown correlation between the levels of sPD-1 in patient sera and cancer progression. sPD-1 levels correlate with sustained high hepatitis B viral load and increased risk of hepatocellular carcinoma.…”