Synergetic and antagonistic effects of combined calcitriol and interferon-β treatment on cytokine production by stimulated PBMCs

Background: We evaluated the effects of calcitriol and interferon-β on in vitro PBMC cytokine production from a cohort of 22 healthy adults not on medication.

Methods: PBMCs were incubated with calcitriol and/or 100 or 400 IU interferon-β or nothing, followed by stimulation with concanavalin A.

Results: When combined, calcitriol and interferon-β appeared to potentiate the effects of one another on reducing IL-6. Calcitriol significantly reduced the production of IL-2, IL-4, IL-6, and IFN-γ, while interferon-β significantly reduced production of IL-6 and TNF-α, and increased IL-10.

Discussion: This is the first study to evaluate the effects of combined calcitriol and interferon-β on cytokine production in PBMCs in vitro, demonstrating novel synergetic effects.