RESUMO
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
RESUMO
Axl is a tyrosine kinase receptor that is commonly overexpressed in many cancers. As such, Axl represents an attractive therapeutic target. The transfer of engineered T cell expressing chimeric antigen receptor (CAR) is an exciting cancer therapeutic approach that shows high efficacy against cancers in clinical trials, especially for B cell malignancies. Furthermore, recently developed synthetic Notch (synNotch) receptor has demonstrated potential in enhancing the specificity of CAR T cell therapy and delivering therapeutic payloads to tumors in an antigen-dependent manner. Therefore, a CAR or synNotch against Axl could be a valuable therapeutic reagent against many cancers. Here, we develop a single-chain variable fragment from a humanized monoclonal antibody against Axl. The scFv is attached to CD3ζ, CD28, and 4-1BB signaling domains to generate an anti-Axl CAR. When introduced into human primary T cells, the anti-Axl CAR can lead to cytokine production and cell killing in response to tumor cells expressing Axl. Moreover, an anti-Axl synNotch generated using the same scFv can be activated with Axl expressing tumor cells. Given the fact that Axl is an important cancer therapeutic target, these receptors could be valuable reagents for developing anti-Axl therapies.
Assuntos
Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Receptores de Antígenos Quiméricos/metabolismo , Receptores Notch/metabolismo , Anticorpos Monoclonais Humanizados , Linhagem Celular Tumoral , Humanos , Imunoterapia Adotiva , Células Jurkat , Células K562 , Engenharia de Proteínas/métodos , Proteínas Proto-Oncogênicas/genética , Receptores Proteína Tirosina Quinases/genética , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos Quiméricos/genética , Receptores Notch/genética , Transdução de Sinais , Anticorpos de Cadeia Única/imunologia , Linfócitos T/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto , Receptor Tirosina Quinase AxlRESUMO
We report on a molecular investigation carried out to ascertain the prevalence of drug-resistant tuberculosis (TB) and the specific gene mutations responsible for resistance to rifampicin (RIF) and/or isoniazid (INH) in Iraq. In total, 110 clinical isolates from category II TB cases from Baghdad (58%) and several Iraqi provinces (42%) were analysed using colorimetric, low-cost and low-density (LCD) microarrays (MYCO-Direct and MYCO-Resist LCD array kits) to identify the point mutations responsible for resistance in Mycobacterium tuberculosis isolates. We found 76 patients (69.1%) had resistant strains, of which 40 (36%) were multidrug-resistant (MDR)-TB. Where mono-resistance was identified, it was found to be predominantly to RIF (83%). The most common mutations were rpoB S531L (50%), inhA C15T (25%) and katG S315T (15%). The most common MDR-TB genotypes were rpoB S531L with inhA C15T (60%) and rpoB S531L with katG S315T (20%). Where phenotypic analysis of clinical isolates was also performed, genotypic data were found to show excellent correlation with phenotypic results. Correlation was found between the MYCO-Resist LCD array and GenoType MTBDRplus for detection of resistance to RIF. Our study shows MDR-TB in 36% of category II TB cases in Baghdad and surrounding Iraqi provinces, which reflects the World Health Organization findings based on phenotypic studies. Diagnosis of TB and MDR-TB using culture-based tests is a significant impediment to global TB control. The LCD arrays investigated herein are easy to use, sensitive and specific molecular tools for TB resistance profiling in resource-limited laboratory settings.
