Interleukin-37, T lymphocytes and natural killer cells in immune thrombocytopenic purpura patients

Abstract

Background

Immune thrombocytopenia (ITP) is an acquired autoimmune disorder characterized by isolated thrombocytopenia with platelets count below (100 × 10
9
l).



Aim and objectives
To determine the serum level of interleukin-37 (IL-37) and investigate the relation between its level, T lymphocytes and natural killer cells (NK) in immune thrombocytopenic purpura cases


Patient and methods
The study was a cross-sectional study done on 90 patients who were split up into three groups; the newly diagnosed ITP group, ITP on therapy group, and the control group. For each group, serum IL-37 was measured by ELISA and T-lymphocytes and NK cell subsets was evaluated by flow cytometry.


Results

The treated ITP group had significantly higher platelets lymphocyte ratio (PLR) (103.04 ± 49.45 vs. 18.44 ± 12.45;
P
1< 0.001) in comparison to newly diagnosed ITP group, while the control group had significantly higher PLR (155.23 ± 108.65 vs. 103.04 ± 49.45;
P
2< 0.001) in comparison to the treated ITP group.


There is a significant change among the three groups as regards the level of IL-37. IL-37 had insignificant correlations with other variables in each separate group, except a significant negative connection amongst IL-37 and platelet count in the treated ITP group (r=–0.31,
P
=0.02) and newly diagnosed ITP group (r=–0.43,
P
< 0.001).


Absolute lymphocyte count was higher in the treated group than newly diagnosed cases of ITP, but it is higher in newly diagnosed ITP group in comparison to control group. Moreover, both treated, and newly diagnosed ITP groups had significantly higher cluster of differentiation (CD) CD3
+
ve T lymphocytes (
P
2< 0.001 and
P
3< 0.001) in comparison to the control group. Meanwhile, the control group had significantly higher CD3
–
ve lymphocytes (B and NK cells) (
P
2< 0.001 and
P
3< 0.001) and total NK cells (
P
2< 0.001, and
P
3< 0.001) in comparison to both groups of ITP.



Conclusion
IL-37 levels in the serum, T lymphocytes and NK cells may be important factors in the course of ITP. In the clinical diagnosis of primary ITP, the utilization of the entire peripheral blood absolute lymphocyte count and PLR levels have the potential to result in a more effective detection and diagnosis outcome and considered as simple and nonexpensive parameters. Patients can receive treatment as early as possible with the help of these parameters, which also has a positive influence on the rate of early diagnosis.