engineering-chimeric-antigen-receptor-natural-killer-cells-targeting

Engineering Chimeric Antigen Receptor-Natural Killer Cells Targeting Fungal Infections Using the Non-viral Sleeping Beauty Transposon System

Chimeric antigen receptor (CAR)-based cell therapies have shown impressive efficacy in the treatment of hematological malignancies. Recently, these ...

Universitätsklinikum Würzburg

Pulmonary mucosal immune response is critical for preventing opportunistic Aspergillus fumigatus infections. Although fungus-specific CD4 T cells in blood are described to reflect the actual host-pathogen interaction status, little is known about Aspergillus-specific pulmonary T-cell responses. Here, we exploit the domestic pig as human-relevant large animal model and introduce antigen-specific T-cell enrichment in pigs to address Aspergillus-specific T cells in the lung compared to peripheral blood. In healthy, environmentally Aspergillus-exposed pigs, the fungus-specific T cells are detectable in blood in similar frequencies as observed in healthy humans and exhibit a Th1 phenotype. Exposing pigs to 10 cfu/m conidia induces a long-lasting accumulation of Aspergillus-specific Th1 cells locally in the lung and also systemically. Temporary immunosuppression during Aspergillus-exposure showed a drastic reduction in the lung-infiltrating antifungal T-cell responses more than 2 weeks after abrogation of the suppressive treatment. This was reflected in blood, but to a much lesser extent. In conclusion, by using the human-relevant large animal model the pig, this study highlights that the blood clearly reflects the mucosal fungal-specific T-cell reactivity in environmentally exposed as well as experimentally exposed healthy pigs. But, immunosuppression significantly impacts the mucosal site in contrast to the initial systemic immune response.

The domestic pig as human-relevant large animal model to study adaptive antifungal immune responses against airborne Aspergillus fumigatus.

The COVID-19 pandemic has resulted in large numbers of patients requiring critical care management. With the established association between severe respiratory virus infection and invasive pulmonary aspergillosis (7.6% for COVID-19-associated pulmonary aspergillosis (CAPA)), the pandemic places a significant number of patients at potential risk from secondary invasive fungal disease. We described a case of CAPA with substantial supporting mycological evidence, highlighting the need to employ strategic diagnostic algorithms and weighted definitions to improve the accuracy in diagnosing CAPA.

A Clinical Case of COVID-19-Associated Pulmonary Aspergillosis (CAPA), Illustrating the Challenges in Diagnosis (Despite Overwhelming Mycological Evidence).

 is a ubiquitous mold that can cause severe infections in immunocompromised patients, typically manifesting as invasive pulmonary aspergillosis (IPA). Adaptive and innate immune cells that respond to  are present in the endogenous repertoire of patients with IPA but are infrequent and cannot be consistently isolated and expanded for adoptive immunotherapy. Therefore, we gene-engineered -specific chimeric antigen receptor (Af-CAR) T cells and demonstrate their ability to confer antifungal reactivity in preclinical models in vitro and in vivo. We generated a CAR targeting domain AB90-E8 that recognizes a conserved protein antigen in the cell wall of  hyphae. T cells expressing the Af-CAR recognized  strains and clinical isolates and exerted a direct antifungal effect against  hyphae. In particular, CD8 Af-CAR T cells released perforin and granzyme B and damaged  hyphae. CD8 and CD4 Af-CAR T cells produced cytokines that activated macrophages to potentiate the antifungal effect. In an in vivo model of IPA in immunodeficient mice, CD8 Af-CAR T cells localized to the site of infection, engaged innate immune cells, and reduced fungal burden in the lung. Adoptive transfer of CD8 Af-CAR T cells conferred greater antifungal efficacy compared to CD4 Af-CAR T cells and an improvement in overall survival. Together, our study illustrates the potential of gene-engineered T cells to treat aggressive infectious diseases that are difficult to control with conventional antimicrobial therapy and support the clinical development of Af-CAR T cell therapy to treat IPA.

Michelle Seif

Medizinische Klinik und Poliklinik II und Lehrstuhl für Zelluläre Immuntherapie,
Medizinische Klinik und Poliklinik II,
Medizinische Klinik und Poliklinik II und Lehrstuhl für Zelluläre Immuntherapie, Medizinische Klinik und Poliklinik II

Universitätsklinikum Würzburg

Engineering Chimeric Antigen Receptor-Natural Killer Cells Targeting Fungal Infections Using the Non-viral Sleeping Beauty Transposon System