Mitochondria Transfer to CD4+ T Cells May Alleviate Rheumatoid Arthritis by Suppressing Pro-Inflammatory Cytokine Production

Abstract

CD4 + T cells contribute to the pathogenesis of autoimmune diseases such as rheumatoid arthritis (RA). These cells infiltrate the joints of RA patients and produce cytokines, including Tumor necrosis factor (TNF)-α, that drive joint inflammation and bone destruction. Although biologic therapeutics targeting T cells and TNF-α have benefited patients suffering from RA, some patients are refractory to these therapies, develop antibodies that neutralize these biologics, or develop undesirable side effects. Recent studies indicate that CD4 + T cell cytokine production is regulated in part by specific metabolic modules, suggesting that immunometabolic pathways could represent a novel therapeutic strategy for T cell-mediated diseases such as RA. Wu et al. (2021) demonstrate that mitochondrial function is impaired in CD4 + T cells from RA patients, leading to reduced levels of various citric acid cycle metabolites (e.g., aspartate) that regulate TNF-α production. Treatment of RA-associated T cells with purified mitochondria was sufficient to restore these metabolic defects, limit production of numerous pro-inflammatory cytokines such as TNF-α and IL-17A, and reduce the development of RA-like disease in a humanized mouse model. These data suggest that T cells can be metabolically “re-engineered” ex vivo with exogenous mitochondria and that this mitochondria transfer approach confers anti-inflammatory properties that may reduce disease severity in RA and possibly other rheumatologic diseases. Increasing our understanding of how intercellular mitochondria transfer occurs may identify novel biological pathways that can be targeted therapeutically or harnessed to support cell engineering.

Role of reactive oxygen species and mitochondrial damage in rheumatoid arthritis and targeted drugs

“…Furthermore, mitochondrial transfer treatment corrects cellular metabolic defects, increases ATP production, and decreases ROS levels. Therefore, mitochondrial transfer has therapeutic potential in regulating immune cell function in RA ( 81 – 83 ).…”

Naringenin ameliorates collagen‐induced arthritis through activating AMPK‐mediated autophagy in macrophages

“…13,14 Ultimately, these pro-inflammatory cytokines interact and promote each other to form a strong inflammatory cascade that induces synovial hyperplasia and enhances histopathological changes in RA. 7,15 The pro-inflammatory factors associated with RA are secreted mainly by activated macrophages present in the articular tissues of RA patients. 16 In addition, the activation of macrophages can also activate osteoclasts, causing pathological absorption and destruction of bone and cartilage.…”

“…In addition, studies have shown that IL‐17 may be a determinant of RA pathogenesis 13,14 . Ultimately, these pro‐inflammatory cytokines interact and promote each other to form a strong inflammatory cascade that induces synovial hyperplasia and enhances histopathological changes in RA 7,15 . The pro‐inflammatory factors associated with RA are secreted mainly by activated macrophages present in the articular tissues of RA patients 16 .…”