The Effect of Systemic Lupus Erythematosus Over the Physiologic Inhibition of 1,25(OH)2D on Monocyte-Tissue Factor (CD142) Expression
Kusworini Handono *
Department of Clinical Pathology, Medical Faculty, Brawijaya University, Saiful Anwar General Hospital Malang, Indonesia.
Intanwati Sherly
Department of Clinical Pathology, Medical Faculty, Brawijaya University, Saiful Anwar General Hospital Malang, Indonesia.
T. Endharti Agustina
Department of Parasitology, Medical Faculty, Brawijaya University, Saiful Anwar General Hospital Malang, Indonesia.
*Author to whom correspondence should be addressed.
Abstract
Background and Aims: Systemic Lupus Erythematosus is a systemic autoimmune disease with increased risk of thrombosis through the induction of tissue factor (TF) expression, the principal initiator of coagulation. Despite its correlation with some autoimmune diseases, including SLE; vitamin D also correlates well with thrombotic events in SLE or non SLE patients. Vitamin D is an immunomodulator that might have an anti-thrombotic effect by down-regulating TF expression in an vitro model of healthy subjects. Therefore, we studied the effect of metabolite active form of vitamin D [1,25(OH)2D] on monocyte-TF (CD142) expression of SLE patients.
Methods: Monocyte culture were obtained from 6 Indonesian SLE patients and 3 age- and sex- matched, healthy Indonesian participants to evaluate the effect of various concentrations of 1,25(OH)2D on monocyte-TF expression in LPS-induced monocytes. The monocyte-TF (CD142) expression was then analyzed by flow cytometry using Monoclonal Anti-human Coagulation Factor III/TF (CD142)-Phycoerythrin and FITC anti-human CD14.
Results: In vitro model of monocyte culture from SLE patients revealed that 1,25(OH)2D showed no inhibitory effects of monocyte-TF expression (p = .275). Higher or lower doses of 1,25(OH)2D did not correlate with high or low CD142 expression in monocyte culture of SLE patients(r=.1, p=.322).
Conclusion: In vitro study of SLE patients showed that 1,25(OH)2D has no inhibitory effect on TF expression. Ten nM 1,25(OH)2D seemed to be the optimal concentration for suppressing LPS-induced monocyte-TF expression in healthy groups but not in SLE groups.
The different characteristics of monocytes, VDR polymorphism, and the need of higher concentration of vitamin D were the best explanation so far for the different effects in monocyte culture of SLE patients.
Keywords: Systemic lupus erythematosus, thrombosis, tissue factor, vitamin D (1,25(OH)2D).