bims-maitce 2026-03-22 papers

Issue of 2026–03–22
two papers selected by
Andy E. Hogan, Maynooth University

J Immunol Res. 2026 ;2026(1): e8201923

Estrogen Induced Regulation of Mucosal-Associated Invariant T Cells in Asthma.

Shubhanshi Trivedi, Samuel E Aamodt, Thomas P Huecksteadt, Elizabeth J Myers, Grace Helen McGee, Jackson G Cacioppo, Jeffrey Aubé, Robert Paine, Daniel T Leung, Kristi J Warren.

Asthma affects over 300 million people worldwide, with increasing rates annually. Males have higher asthma prevalence in adolescence, while females exhibit higher rates in adulthood. Reduced mucosal-associated invariant T (MAIT) cells are found in severe asthmatic airway disease. We hypothesize MAIT cells modulate airway inflammation and are regulated by sex hormones through their cognate hormone receptors. We compared circulating MAIT cells and ex vivo MAIT cell activation with MR-1 ligand in controls and asthmatic individuals. MAIT cells were significantly lower in asthmatic males and females compared to healthy controls. MAIT cells derived from male and female asthma patients exhibited higher levels of estrogen receptors (ERs) than those from sex-matched healthy controls, and ex vivo treatment with estrogen significantly decreased IFN-γ production in asthmatics. Estrogen treatment did not reduce IFN-γ in MAIT cells from healthy individuals. To explore the effect of estrogen on MAIT cells, we used the murine Alternaria alternata challenge model. Adoptive transfer of G-protein coupled ER (GPER-1) antagonist (G36)-treated MAIT cells into Rag1 knockout mice (Rag1-/-) increased A. alternata-induced inflammation compared to those receiving MAIT cells without GPER-1 blockade. These findings suggest GPER-1 as a novel target to reduce airway disease in the asthmatic population.

Keywords: G-protein coupled estrogen receptor (GPER-1); asthma; estrogen (E2); estrogen receptors (ER) α and ERβ; interleukin-2 (IL-2) IL-7 IL-12 IL-15 IL-18; mucosal-associated invariant T (MAIT) cells

DOI: https://doi.org/10.1155/jimr/8201923

J Immunol. 2026 Mar 17. pii: vkag001. [Epub ahead of print]215(3):

Revisiting T cells: Innate actions and emerging links to innate memory response.

Kim A Tran, Maziar Divangahi.

The traditional view of the immune system distinguishes between the innate immune system, which serves as the host's first line of defense against pathogens, and the adaptive immune system, which evolved to manage more complex or recurrent infections. However, the discovery of evolutionarily conserved mechanisms in innate memory cells (trained immunity) has revealed adaptive-like characteristics in innate immune cells, challenging the conventional dogma between innate and adaptive immunity. Simultaneously, growing evidence shows that T cells exhibit innate-like features. In this review, we explore unconventional T cells (γδ cells, natural killer T cells, mucosal-associated invariant T cells) and conventional αβ T cells (virtual memory, memory T cells) to emphasize the broad spectrum of beneficial effects that the adaptive immune system can particularly exert in early host defense strategies, including innate immune memory. These mechanisms confer clear advantages for immune protection and homeostasis, especially during early childhood, and provide a new perspective on canonical immune functions.

Keywords: T cells; innate-like T cells; memory; trained immunity

DOI: https://doi.org/10.1093/jimmun/vkag001