Project description:Immune evasion is a hallmark of cancer, and therapies that restore immune surveillance have proven highly effective in cancers with high tumor mutation burden (TMB) (e.g., those with microsatellite instability (MSI)). Whether low TMB cancers, which are largely refractory to immunotherapy, harbor potentially immunogenic neoantigens remains unclear. Here, we show that tumors from all patients with microsatellite stable (MSS) colorectal cancer (CRC) express clonal predicted neoantigens despite low TMB. Unexpectedly, these neoantigens are broadly expressed at lower levels compared to those in MSI CRC. Using a versatile platform for modulating neoantigen expression in CRC organoids and transplantation into the distal colon of mice, we show that low expression precludes productive cross priming and drives immediate T cell dysfunction. Strikingly, experimental or therapeutic rescue of priming rendered T cells capable of controlling tumors with low neoantigen expression. These findings underscore a critical role of neoantigen expression level in immune evasion and therapy response.
Project description:Multi-targeting priming (MTP) for genome-wide gene expression assays provides selective targeting of multiple sequences and counter-selection against undesirable sequences. We demonstrated superior performance of two MTPs compared to oligo-dT microarray profling and RNA tag sequencing the response of Saccharomyces cerevisiae to nitrogen deficiency and profiling Neurospora crassa early sexual development. Priming with MTPs in addition to oligo-dT resulted in higher sensitivity, a greater number of well-measured genes, more genes significantly differentially expressed, and a greater power to detect meager differences. Neurospora crassa mat A FGSC#2489 2 developmental stages and oligo(dT) primers.
Project description:Multi-targeting priming (MTP) for genome-wide gene expression assays provides selective targeting of multiple sequences and counter-selection against undesirable sequences. We demonstrated superior performance of two MTPs compared to oligo-dT microarray profling and RNA tag sequencing the response of Saccharomyces cerevisiae to nitrogen deficiency and profiling Neurospora crassa early sexual development. Priming with MTPs in addition to oligo-dT resulted in higher sensitivity, a greater number of well-measured genes, more genes significantly differentially expressed, and a greater power to detect meager differences. Neurospora crassa mat A FGSC#2489 Three developmental stages and two different primers used for reverse transcription: mycelium oligo(dT) M1 protoperithecia oligo(dT) PP1 perithecia oligo(dT) PT1 mycelium oligo(dT)+ Multi-Targeted Primer [MTP] (M2) protoperithecia oligo(dT)+ MTP (PP2) perithecia oligo(dT)+ MTP (PT2)
Project description:Research on forms of memory in innate immune systems has recently gained momentum with the study of trained immunity in vertebrates and immune priming in invertebrates. Immune priming provides protection against previously encountered pathogens. However, causes and mechanisms of immune priming are still not well understood in most organisms. In this work, we combine RNA sequencing with transmission electron microscopy to investigate the dynamic processes during priming in the gut of a well-established model for oral immune priming, consisting of the host Tribolium castaneum and its entomopathogen Bacillus thuringiensis tenebrionis (Btt). We show that priming with specific, non-infectious pathogen-derived cues causes damage in the gut of T. castaneum larvae, which leads to an early physiological stress response as well as the upregulation of a specific set of immune genes. This response diminishes over time yet enables the gut to upregulate genes known to interfere with Btt virulence when T. castaneum larvae are later exposed to infectious Btt spores. These insights contribute to our understanding of immune priming as a dynamic process where cellular responses in concert with specific gene regulation prepare the gut tissue and thereby enables a more efficient protection against infection. Such work can further help us understand the origin and mechanism of innate immune memory.
Project description:Multi-targeting priming (MTP) for genome-wide gene expression assays provides selective targeting of multiple sequences and counter-selection against undesirable sequences. We demonstrated superior performance of two MTPs compared to oligo-dT microarray profling and RNA tag sequencing the response of Saccharomyces cerevisiae to nitrogen deficiency and profiling Neurospora crassa early sexual development. Priming with MTPs in addition to oligo-dT resulted in higher sensitivity, a greater number of well-measured genes, more genes significantly differentially expressed, and a greater power to detect meager differences.
Project description:This SuperSeries is composed of the following subset Series: GSE22658: Neurospora crassa early sexual development with MTP priming GSE22936: Saccharomyces cerevisiae grown in nitrogen depletion with MTP priming GSE22972: Neurospora crassa early sexual development with oligod(T) priming GSE22992: Saccharomyces cerevisiae grown in nitrogen depletion with oligodT priming Refer to individual Series
Project description:Multi-targeting priming (MTP) for genome-wide gene expression assays provides selective targeting of multiple sequences and counter-selection against undesirable sequences. We demonstrated superior performance of two MTPs compared to oligo-dT microarray profling and RNA tag sequencing the response of Saccharomyces cerevisiae to nitrogen deficiency and profiling Neurospora crassa early sexual development. Priming with MTPs in addition to oligo-dT resulted in higher sensitivity, a greater number of well-measured genes, more genes significantly differentially expressed, and a greater power to detect meager differences.
Project description:Innate immune priming increases an organism’s survival of a second infection after an initial, non-lethal infection. We used Drosophila melanogaster and an insect-derived strain of Enterococcus faecalis to study transcriptional control of priming. In contrast to other pathogens, the enhanced survival in primed animals does not correlate with decreased E. faecalis load. Further analysis shows that primed organisms tolerate, rather than resist infection. Using RNA-seq of immune tissues, we found many genes were upregulated in only primed flies, suggesting a distinct transcriptional program in response to initial and secondary infections. In contrast, few genes continuously express throughout the experiment or more efficiently re-activate upon reinfection. Priming experiments in immune deficient mutants revealed Imd is largely dispensable for responding to a single infection but needed to fully prime. Together, this indicates the fly’s innate immune response is plastic — differing in immune strategy, transcriptional program, and pathway use depending on infection history.