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Biology subjects

Kuka, M.

Publications and source records attributed to Kuka, M..

4 recordsLinked to original sources

LSD1 inhibition improves efficacy of adoptive T cell therapy by enhancing CD8+ T cell responsiveness.

The lysine-specific histone demethylase 1A (LSD1) has been described to play a role in antitumor immunity; however, the role of LSD1 in shaping CD8+ T cell (CTL) differentiation and function is not understood. Here, we showed that pharmacological inhibition of LSD1 (LSD1i) in CTL elicited phenotypic and functional alterations of the CTL that led to robust antitumor immunity in the context of adoptive T cell therapy (ACT). In addition, the combination of anti-PDL1 therapy with LSD1i-based ACT resulted in a complete tumor eradication and long-lasting tumor-free survival. This study demonstrated that LSD1i together with anti-PDL1 therapy complement each others deficiencies and produce a better tumor response in a melanoma model, in which both immune and epigenetic therapy alone have shown limited efficacy. Collectively, these results set the translational potential of modulating LSD1 to improve antitumoral responses generated by ACT and anti-PDL1 therapy, which provide a strong rationale for a combination trial of LSD1i and immunotherapy.

immunology↗

A fluorescent reporter model for the visualization and characterization of TDC

TDC are hematopoietic cells that combine dendritic cell (DC) and conventional T cell markers and functional properties. They were identified in secondary lymphoid organs (SLOs) of naive mice as cells expressing CD11c, major histocompatibility molecule (MHC)-II, and the T cell receptor (TCR) {beta} chain. Despite thorough characterization as to their potential functional properties, a physiological role for TDC remains to be determined. Unfortunately, using CD11c as a marker for TDC has the caveat of its upregulation on different cells, including T cells, upon activation. Therefore, a more specific marker is needed to further investigate TDC functions in peripheral organs in different pathological settings. Here we took advantage of Zbtb46-GFP reporter mice to explore the frequency and localization of TDC in peripheral tissues at steady state and upon viral infection. RNA sequencing analysis confirmed that TDC identified with this reporter model have a gene signature that is distinct from conventional T cells and DC. In addition, frequency and total numbers of TDC in the SLOs recapitulated those found using CD11c as a marker. This reporter model allowed for identification of TDC in situ not only in SLOs but also in the liver and lung of naive mice. Interestingly, we found that TDC numbers in the SLOs increased upon viral infection, suggesting that TDC might play a role during viral infections. In conclusion, we propose a visualization strategy that might shed light on the physiological role of TDC in several pathological contexts, including infection and cancer.

immunology↗

The guanine nucleotide exchange factor Rin-like acts as a gatekeeper for T follicular helper cell differentiation via regulating CD28 signaling

T follicular helper (Tfh) cells are essential for the development of germinal center B cells and high-affinity antibody producing B-cells in human and mice. Here, we identify the guanine nucleotide exchange factor (GEF) Rin-like (Rinl) as a negative regulator of Tfh generation. Loss of Rinl leads to an increase of Tfh in aging, upon in vivo immunization and acute LCMV Armstrong infection in mice, and in human CD4+ T cell in vitro cultures. Further, adoptive transfer experiments using WT and Rinl-KO naive CD4+ T cells unraveled T cell-intrinsic functions of Rinl. Mechanistically, Rinl regulates CD28 internalization and signaling, thereby shaping CD4+ T cell activation and differentiation. Thus, our results identify the GEF Rinl as a negative regulator of global Tfh differentiation in an immunological context and species-independent manner, and furthermore connect Rinl with CD28 internalization and signaling pathways in CD4+ T cells, demonstrating for the first-time the importance of endocytic processes for Tfh differentiation. HighlightsO_LIRinl-KO CD4+ T cells show increased Tfh differentiation in a context independent manner C_LIO_LIThe regulation of Tfh differentiation is T cell-intrinsic C_LIO_LIRinl controls CD28 endocytosis and shapes Tfh-specific CD28 signal transduction C_LIO_LIHuman Tfh differentiation is regulated by Rinl C_LI

immunology↗

Controlled administration of aerosolized SARS-CoV-2 to K18-hACE2 transgenic mice uncouples respiratory infection and anosmia from fatal neuroinvasion

The development of a tractable small animal model faithfully reproducing human COVID-19 pathogenesis would arguably meet a pressing need in biomedical research. Thus far, most investigators have used transgenic mice expressing the human ACE2 in epithelial cells (K18-hACE2 transgenic mice) that are intranasally instilled with a liquid SARS-CoV-2 suspension under deep anesthesia. Unfortunately, this experimental approach results in disproportionate high CNS infection leading to fatal encephalitis, which is rarely observed in humans and severely limits this models usefulness. Here, we describe the use of an inhalation tower system that allows exposure of unanesthetized mice to aerosolized virus under controlled conditions. Aerosol exposure of K18-hACE2 transgenic mice to SARS-CoV-2 resulted in robust viral replication in the respiratory tract, anosmia, and airway obstruction, but did not lead to fatal viral neuroinvasion. When compared to intranasal inoculation, aerosol infection resulted in a more pronounced lung pathology including increased immune infiltration, fibrin deposition and a transcriptional signature comparable to that observed in SARS-CoV-2- infected patients. This model may prove useful for studies of viral transmission, disease pathogenesis (including long-term consequences of SARS-CoV-2 infection) and therapeutic interventions.

immunology↗