Biology subjects

Oestreich, K. J.

Publications and source records attributed to Oestreich, K. J..

3 recordsLinked to original sources

bioRxiv2022

Eos promotes TH2 differentiation by propagating the IL-2/STAT5 signaling pathway.

The Ikaros zinc finger transcription factor Eos has been commonly implicated in regulatory T cells to promote their immunosuppressive functions. Paradoxically, a new role is emerging for Eos in promoting pro-inflammatory responses of conventional CD4+ T cells in the dysregulated setting of autoimmunity. Even so, the precise role of Eos in regulating the differentiation and function of healthy effector CD4+ T cell subsets remains unclear. Here, we find that Eos is a positive regulator of CD4+ T helper 2 (TH2) cells--effector T cells implicated in the induction of allergic asthma. Using murine in vitro TH2 cells and an in vivo house dust mite asthma model, we found that Eos-deficient T cells had reduced expression of key TH2 transcription factors, effector cytokines, and differentiation receptors. Mechanistically, among various TH2-polarizing pathways, the IL-2/STAT5 axis and its downstream TH2 gene targets emerged as one of the most significantly downregulated networks in Eos deficiency. Using in vitro TH2 cells and overexpression of Eos zinc-finger-domain mutants, we discovered that Eos forms a novel complex with and supports the tyrosine-phosphorylated signaling activity of STAT5. Overall, these data define a novel regulatory mechanism whereby Eos promotes IL-2/STAT5 activity to facilitate TH2 differentiation.

immunology↗

bioRxiv2022

Aiolos modulates the TFH and CD4-CTL differentiation programs via reciprocal regulation of the Zfp831/TCF-1/Bcl-6 axis and CD25

Effective immunity to influenza virus and other respiratory viruses requires the generation of CD4+ T cell subsets that coordinate multiple aspects of the immune response. These subsets include T follicular helper (TFH) and T helper 1 (TH1) cells, which promote humoral and cell-mediated responses, respectively. A third population, CD4+ cytotoxic T lymphocytes (CD4-CTLs) facilitates clearance of infection via mechanisms normally associated with CD8+ T cells. Here, we identify the transcription factor Aiolos as a regulator of TFH and CD4-CTL responses. We demonstrate that Aiolos deficiency compromises TFH differentiation and antibody production during influenza virus infection. Conversely, we find that CD4+ T cells acquire a cytotoxic-like program in the absence of Aiolos, including increased expression of the CTL-associated transcription factors Eomes and Blimp-1. We further show that while Aiolos positively regulates the TFH transcriptional regulators Zfp831, TCF-1 and Bcl-6, it also directly represses expression of IL-2R and IL-2/STAT5-driven expression of the cytotoxic gene program. Thus, our findings identify Aiolos as a pivotal regulator of TFH and CD4-CTL differentiation and highlight its potential as a target for manipulating CD4+ T cell humoral and cytotoxic responses.

immunology↗

bioRxiv2022

Prime-pull immunization of mice with a BcfA-adjuvanted vaccine elicits mucosal immunity and prevents SARS CoV-2 infection and pathology

Vaccines against SARS-CoV-2 that induce mucosal immunity capable of preventing infection and disease remain urgently needed. We show that intramuscular priming of mice with an alum and BcfA-adjuvanted Spike subunit vaccine, followed by a BcfA-adjuvanted mucosal booster, generated Th17 polarized tissue resident CD4+ T cells, and mucosal and serum antibodies. The serum antibodies efficiently neutralized SARS-CoV-2 and its Delta variant, suggesting cross-protection against a recent variant of concern (VOC). Immunization with this heterologous vaccine prevented weight loss following challenge with mouse-adapted SARS-CoV-2 and reduced viral replication in the nose and lungs. Histopathology showed a strong leukocyte and polymorphonuclear (PMN) cell infiltrate without epithelial damage in mice immunized with BcfA-containing vaccines. In contrast, viral load was not reduced in the upper respiratory tract of IL-17 knockout mice immunized with the same formulation, suggesting that the Th17 polarized T cell responses are critical for protection. We show that vaccines adjuvanted with alum and BcfA, delivered through a heterologous prime-pull regimen, protect against SARS-CoV-2 infection without causing enhanced respiratory disease. SIGNIFICANCEThere remains a need for SARS CoV-2 booster vaccines that generate mucosal immunity and prevent transmission. We show that systemic priming followed by a mucosal booster with a BcfA-adjuvanted subunit vaccine generates neutralizing antibodies and Th17 polarized systemic and tissue-resident immune responses that provide sterilizing immunity against wildtype SARS CoV-2, and a variant of concern. Importantly, in contrast to alum alone, the addition of BcfA prevents respiratory pathology. These results suggest that a BcfA-adjuvanted mucosal booster may elicit mucosal immunity in individuals previously immunized systemically with approved vaccines. This foundational study in mice sets the stage for testing our vaccine regimen in larger animal models as a booster vaccine.

immunology↗