The following is a summary of “Azathioprine therapy induces selective NK cell depletion and IFN-γ deficiency predisposing to herpesvirus reactivation,” published in the JANUARY 2023 issue of Allergy & Immunology by Ingelfinger, et al.

For those with chronic inflammatory disorders such myasthenia gravis or organ transplant recipients, azathioprine is a commonly recommended medication. By blocking intracellular purine production and lowering the amount of circulating B and T lymphocytes, azathioprine has immunosuppressive effects. However, case studies showed that there was a higher chance of developing severe infections with azathioprine therapy, even when lymphocyte levels are regularly checked. For a study, researchers intended to thoroughly examine the underlying immunological dysfunction caused by azathioprine usage and therapy-related patient concerns.

To identify the precise effects of azathioprine usage on the systemic immunological signature, single-cell mass and spectral flow cytometry were used to examine peripheral blood leukocytes. Two separate cohorts of individuals with myasthenia gravis who were receiving therapy had their clinical characteristics examined.

Selectively causing substantial CD56^dimCD16⁺ natural killer cell depletion and concurrent IFN-γ deficiency, azathioprine treatment. A unique constriction of classical T₊1 cells with azathioprine therapy was identified by cytokine profiling. Additionally, we noticed that individuals with myasthenia gravis who were on azathioprine experienced endogenous latent herpesvirus reactivation more frequently than those who weren’t; the higher frequency was confirmed in a separate cohort of patients.

The findings emphasized the potential for adverse events to arise during azathioprine medication and implied that natural killer cell monitoring may be useful in clinical practice.

Reference: jacionline.org/article/S0091-6749(22)01187-3/fulltext