Liver Type 1 innate lymphoid cells (ILCs) comprise conventional natural killer (cNK) cells and ILC1s. The main functions of Type 1 ILCs not only include directly killing target cells but also regulating the local immune microenvironment of the liver through the secretion of cytokines. Uncovering the intricate mechanisms by which transcriptional factors regulate and influence the functions of Type 1 ILCs, particularly within the context of liver tumors, presents a significant opportunity to amplify the effectiveness of immunotherapies against liver malignancies. Using Ncr1-drived conditional knockout mouse model, our study reveals the regulatory role of Prdm1 in shaping the composition and maturation of liver Type 1 ILCs. Notably, Prdm1 regulates the ratio between NK cells and ILC1s, promoting a shift in the balance towards the direction of NK cells. Although Prdm1 did not affect the killing function of cNK cells in an in vivo cytotoxicity model, a significant increase in cancer metastasis was observed in Prdm1 knockout mice. IFN-γ, granzyme B, and perforin secretion decreased significantly in Prdm1 deficient Type 1 ILCs. scRNA sequencing data also provided evidence that Prdm1 sustains functional subsets of liver type 1 ILCs and facilitates communications between Type 1 ILCs and macrophages. The present study unveiled a novel regulatory mechanism of Prdm1 in liver Type 1 ILCs, showing promising potential for developing innovative immune therapy strategies against liver cancer.
Four cellobiohydrolase I (CBHI) glycoforms, namely, CBHI-A, CBHI-B, CBHI-C, and CBHI-D, were purified from the cultured broth of Penicillium decumbens JU-A10. All glycoforms had the same amino acid sequence but displayed different characteristics and biological functions. The effects of the N-glycans of the glycoforms on CBH activity were analyzed using mass spectrum data. Longer N-glycan chains at the Asn-137 of CBHI increased CBH activity. After the N-glycans were removed using site-directed mutagenesis and homologous expression in P. decumbens, the specific CBH activity of the recombinant CBHI without N-glycosylation increased by 65% compared with the wild-type CBHI with the highest specific activity. However, the activity was not stable. Only the N-glycosylation at Asn-137 can improve CBH activity by 40%. rCBHI with N-glycosylation only at Asn-470 exhibited no enzymatic activity. CBH activity was affected whether or not the protein was glycosylated, together with the N-glycosylation site and N-glycan structure. N-Glycosylation not only affects CBH activity but may also bring a new feature to a nonhydrolytic CBHI glycoform (CBHI-A). By supplementing CBHI-A to different commercial cellulase preparations, the glucose yield of lignocellulose hydrolysis increased by >20%. After treatment with a low dose (5 mg/g substrate) of CBHI-A at 50 °C for 7 days, the hydrogen-bond intensity and crystalline degree of cotton fibers decreased by 17 and 34%, respectively. These results may provide new guidelines for cellulase engineering.
Abstract Aldo-keto oxidoreductase (AKR) inhibitors could reverse several cancer cells’ resistance to Cis-platin, but their role in resistance remains unclear. Our RNA-seq results showed de novo NAD biosynthesis-related genes, and NAD(P)H-dependent oxidoreductases were significantly upregulated in Cis-platin-resistant HepG2 hepatic cancer cells (HepG2-RC cells) compared with HepG2 cells. Knockdown of AKR1Cs could increase Cis-platin sensitivity in HepG2-RC cells about two-fold. Interestingly, the AKR1C inhibitor meclofenamic acid could increase Cis-platin sensitivity of HepG2-RC cells about eight-fold, indicating that knockdown of AKR1Cs only partially reversed the resistance. Meanwhile, the amount of total NAD and the ratio of NADH/NAD+ were increased in HepG2-RC cells compared with HepG2 cells. The increased NADH could be explained as a directly operating antioxidant to scavenge radicals induced by Cis-platin. We report here that NADH, which is produced by NAD(P)H-dependent oxidoreductases, plays a key role in the AKR-associated Cis-platin resistance of HepG2 hepatic cancer cells.
Single-cell protein (SCP) production in the methylotrophic yeast Pichia pastoris has the potential to achieve a sustainable protein supply. However, improving the methanol fermentation efficiency and reducing carbon loss has been a long-standing challenge with far-reaching scientific and practical implications. Here, comparative transcriptomics revealed that PAS_0305, a gene directly associated with cell wall thickness under methanol stress, can be used as a target for unlocking cell wall sensors. Intracellular trehalose accumulation confirmed that cell wall sensors were activated after knocking out PAS_0305, which resulted in increased cell wall permeability. Genome-wide signal perturbations were transduced through the HOG module and the CWI pathway, which was confirmed to connected by Pbs2-Mkk. As a consequence of CWI pathway activation, ΔPAS_0305 elicited a rescue response of cell wall remodeling by increasing the β-1,3-glucan content and decreasing the chitin/mannose content. Remarkably, perturbations in global stress signals led to a fine-tuning of the metabolic network of ΔPAS_0305, resulting in a superior phenotype with highest crude protein and methanol conversion rate of 67.21% and 0.46 gDCW/g. Further genome-scale metabolic models were constructed to validate the experimental results, confirming that unlocking cell wall sensors resulted in maximized flux from methanol towards SCP and effectively addressing the issue of carbon loss in methanol fermentation. This work sheds new light on the potential of manipulating cellular signaling pathways to optimize metabolic networks and achieve exceptional phenotypic characteristics, providing new strategies for constructing versatile cell factories in P. pastoris.
Abstract Multiple studies have confirmed the occurrence of second tumors as a rare incidence of CAR-T therapy, but one of the complications that does warrant in-depth exploration. According, given the relatively small number of reported second tumor types thus far, additional comprehensive occurrence and characterization of a new second tumor type after CAR-T therapy remains essential for understanding the risk of potential tumors with this therapy, as well as for defining the role of immune microenvironment in malignant transformation. In this article, a new second tumor type CMML was identified in a patient who had received CD19 CAR-T therapy for DLBCL. The immune microenvironment of both the pre- and post-treatment of secondary CMML and primary CMML were deeply profiled by ScRNA-seq. Our results demonstrated an enhanced inflammatory cytokines, chemokines, and immunosuppression state of monocytes/macrophages, which may inhibit the cytotoxicity of T/NKs in secondary CMML. In contrast, the cytotoxicity of T/NKs were enhanced in secondary CMML after treatment. Collectively, our results highlight a new type of second tumor, CMML after CAR-T therapy and provide a framework for defining the immune microenvironment of second tumor occurrence after CAR-T therapy. Our results also provide a rationale for targeting macrophages to strengthen CMML treatment.
Abstract Lignocellulosic biomass is an abundant renewable feedstock, but its complex structure of lignocellulose poses barriers to its enzymatic hydrolysis and fermentation. Fungi possess diverse lignocellulolytic enzyme systems that synergistically deconstruct lignocellulose into soluble sugars for fermentation. This review elucidates recent advances in understanding the molecular mechanisms underpinning fungal degradation of lignocellulose. We analyze major enzyme classes tailored by fungi to depolymerize cellulose, hemicellulose, and lignin. Highlighted are the concerted actions and intimate partnerships between these biomass‐degrading enzymes. Current challenges impeding large‐scale implementation of enzymatic hydrolysis are discussed, along with emerging biotechnological opportunities. Advanced pretreatments, high‐throughput enzyme engineering platforms, and machine learning or artificial intelligence‐guided lignocellulolytic enzyme cocktail optimization represent promising ways to improve hydrolytic efficiencies. Elucidating the coordinated interplay and regulation of fungal lignocellulolytic machinery can facilitate optimization of fungal biotechnology platforms. Harnessing the efficiency of fungal biomass deconstruction promises to enhance the development of biorefinery processes for sustainable bioenergy.