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Hassan, K.

Publications and source records attributed to Hassan, K..

4 recordsLinked to original sources

Engineering Endogenous T Cell Receptors to Recognize Cancer Neoantigens Using a Hybrid Physics-AI Approach

T cell receptors (TCRs) are critical for immune surveillance and successful adaptive immune response against foreign antigens. TCRs drive this key arm of the immune system through recognition of peptide epitopes presented on MHC complexes. However, they are limited due to their stochastic nature and generation via genetic recombination. In silico design of functional TCRs that target defined peptide epitopes would be of considerable utility but has up until now been unsuccessful. Here, we develop an artificial intelligence (AI)-powered approach using a hybrid physics-based simulation and generative AI that successfully engineers TCRs against defined epitopes presented by MHC-I. We use this approach to design TCRs against two cancer antigens, a HERC1 neoantigen and an immunogenic neoepitope in mutant EGFR. We engineer multiple TCRs against the HERC1 neoantigen which activate T cells in response to exposure to peptide-MHC I and kill cancer cells more effectively than a patient-derived TCR. In addition, we used generative AI to design functional TCRs that target the EGFR T790M neoantigen, engineering greater specificity against the mutant sequence. We present an AI-based approach to TCR design with broad utility for efforts to engineer TCRs and for the development of new cell therapies. One sentence summaryArtificial intelligence-based approach enables the directed engineering of functional TCRs with enhanced features that target cancer neoantigens.

immunology↗

Neurotrophic and immunomodulatory lanostane triterpenoids from wood-inhabiting Basidiomycota

Neurotrophins such as nerve growth factor (ngf) and brain derived neurotrophic factor (bdnf) play important roles in the central nervous system. They are potential therapeutic drugs for treatment of neurodegerative diseases including Alzheimers disease and Parkinsons disease. In this study, we investigated the neurotrophic properties of triterpenes isolated from fruiting bodies of Laetiporus sulphureus and a mycelial culture of Antrodia sp. MUCL 56049. The structures of the isolated compounds were elucidated based on nuclear magnetic resonance (NMR) spectroscopy in combination with high-resolution Electrospray mass spectrometry (HR-ESIMS). The secondary metabolites were tested for neurotrophin (ngf and bdnf) expression levels on human astrocytoma 1321N1 cells. Neurite outgrowth activity using rat pheochromocytoma (PC-12) cells was also determined. Twelve triterpenoids were isolated, of which several potently stimulated the expression of neurotrophic factors namely, ngf (sulphurenic acid, 15-dehydroxytrametenolic acid, fomefficinic acid D and 16-hydroxyeburicoic acid) and bdnf (sulphurenic acid and 15- dehydroxytrametenolic acid), respectively. The triterpenes also potentiated ngf-induced neurite outgrowth in PC-12 cells. This is, to the best of our knowledge, the first report on the compound class of lanostanes in direct relation to bdnf and ngf enhancement. These compounds are widespread in medicinal mushrooms; hence, they appear promising as starting point for development of drugs and mycopharmaceuticals to combat neurodegenerative diseases. Interestingly, they do not show any pronounced cytotoxicity and may therefore be better suited for therapy than many other neurotrophic compounds that were previously reported.

biochemistry↗

Disruption of the surfactant protein A receptor SP-R210L (CD245α/MYO18Aα) alters respiratory function and iron sequestration in alveolar macrophages of aged mice

Previous studies demonstrated that the host defense collectins, surfactant protein A and complement component 1q, modulate tissue-dependent macrophage activation, pathogen clearance, and regulatory macrophage functions through the receptor SP-R210, which consists of two isoforms SP-R210L and SP-R210S. These isoforms are encoded by alternatively spliced mRNAs of the Myo18a MYO18A gene in mice and humans. The present study in conditional transgenic mice revealed novel age-related functions of the SP-R210L isoform in modulating pulmonary mechanics, iron sequestration in alveolar macrophages (AMs), and life-long maintenance of the alveolar macrophage population. Our findings support the novel idea that SP-R210L-deficient AMs undergo bi-directional epigenetic adaptation that results in chronic dysregulation of broncho-alveolar function, immune homeostasis, and maintenance of oncotic balance at the airway-capillary interface. Disruption of SP-R210L increases the risk for development of severe interstitial lung disease during development and aging.

physiology↗

Chitin is present within the Ampullae of Lorenzini of chondrichthyan fishes

ABSTRACTChitin is synthesized by a variety of organisms using enzymes called chitin synthases and was recently discovered in a number of aquatic vertebrates. In our ongoing investigations into the presence of vertebrate chitin, we unexpectedly found evidence of the polysaccharide within the electrosensory organs, known as Ampullae of Lorenzini, of diverse chondrichthyan fishes. Experiments with histochemical reagents, chemical analyses, and enzymatic digestions suggested that chitin is a component of the hydrogel filling the structures. Further, in situ hybridization with a sequence from the little skate (Leucoraja erinacea) revealed that chitin synthase expression is localized to cells inside the organs. Collectively, these findings suggest that chondrichthyan fishes endogenously synthesize chitin and beg further investigation into the function of chitin in the electrosensory system.Competing Interest StatementThe authors have declared no competing interest.View Full Text

molecular biology↗