Genetic and environmental interactions contribute to immune variation in rewilded mice.

The relative and synergistic contributions of genetics and environment to interindividual immune response variation remain unclear, despite implications in evolutionary biology and medicine. Here we quantify interactive effects of genotype and environment on immune traits by investigating C57BL/6, 129S1 and PWK/PhJ inbred mice, rewilded in an outdoor enclosure and infected with the parasite Trichuris muris. Whereas cellular composition was shaped by interactions between genotype and environment, cytokine response heterogeneity including IFNγ concentrations was primarily driven by genotype with consequence on worm burden. In addition, we show that other traits, such as expression of CD44, were explained mostly by genetics on T cells, whereas expression of CD44 on B cells was explained more by environment across all strains. Notably, genetic differences under laboratory conditions were decreased following rewilding. These results indicate that nonheritable influences interact with genetic factors to shape immune variation and parasite burden.

Phosphatidylserine vesicles enable efficient en bloc transmission of enteroviruses.

A central paradigm within virology is that each viral particle largely behaves as an independent infectious unit. Here, we demonstrate that clusters of enteroviral particles are packaged within phosphatidylserine (PS) lipid-enriched vesicles that are non-lytically released from cells and provide greater infection efficiency than free single viral particles. We show that vesicular PS lipids are co-factors to the relevant enterovirus receptors in mediating subsequent infectivity and transmission, in particular to primary human macrophages. We demonstrate that clustered packaging of viral particles within vesicles enables multiple viral RNA genomes to be collectively transferred into single cells. This study reveals a novel mode of viral transmission, where enteroviral genomes are transmitted from cell-to-cell en bloc in membrane-bound PS vesicles instead of as single independent genomes. This has implications for facilitating genetic cooperativity among viral quasispecies as well as enhancing viral replication.

The hyphal-specific toxin candidalysin promotes fungal gut commensalism.

The fungus Candida albicans frequently colonizes the human gastrointestinal tract, from which it can disseminate to cause systemic disease. This polymorphic species can transition between growing as single-celled yeast and as multicellular hyphae to adapt to its environment. The current dogma of C. albicans commensalism is that the yeast form is optimal for gut colonization, whereas hyphal cells are detrimental to colonization but critical for virulence1-3. Here, we reveal that this paradigm does not apply to multi-kingdom communities in which a complex interplay between fungal morphology and bacteria dictates C. albicans fitness. Thus, whereas yeast-locked cells outcompete wild-type cells when gut bacteria are absent or depleted by antibiotics, hyphae-competent wild-type cells outcompete yeast-locked cells in hosts with replete bacterial populations. This increased fitness of wild-type cells involves the production of hyphal-specific factors including the toxin candidalysin4,5, which promotes the establishment of colonization. At later time points, adaptive immunity is engaged, and intestinal immunoglobulin A preferentially selects against hyphal cells1,6. Hyphal morphotypes are thus under both positive and negative selective pressures in the gut. Our study further shows that candidalysin has a direct inhibitory effect on bacterial species, including limiting their metabolic output. We therefore propose that C. albicans has evolved hyphal-specific factors, including candidalysin, to better compete with bacterial species in the intestinal niche.

Variable susceptibility of intestinal organoid-derived monolayers to SARS-CoV-2 infection.

Gastrointestinal effects associated with Coronavirus Disease 2019 (COVID-19) are highly variable for reasons that are not understood. In this study, we used intestinal organoid-derived cultures differentiated from primary human specimens as a model to examine interindividual variability. Infection of intestinal organoids derived from different donors with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) resulted in orders of magnitude differences in virus replication in small intestinal and colonic organoid-derived monolayers. Susceptibility to infection correlated with angiotensin I converting enzyme 2 (ACE2) expression level and was independent of donor demographic or clinical features. ACE2 transcript levels in cell culture matched the amount of ACE2 in primary tissue, indicating that this feature of the intestinal epithelium is retained in the organoids. Longitudinal transcriptomics of organoid-derived monolayers identified a delayed yet robust interferon signature, the magnitude of which corresponded to the degree of SARS-CoV-2 infection. Interestingly, virus with the Omicron variant spike (S) protein infected the organoids with the highest infectivity, suggesting increased tropism of the virus for intestinal tissue. These results suggest that heterogeneity in SARS-CoV-2 replication in intestinal tissues results from differences in ACE2 levels, which may underlie variable patient outcomes.

Viral reorganization of the secretory pathway generates distinct organelles for RNA replication.

Many RNA viruses remodel intracellular membranes to generate specialized sites for RNA replication. How membranes are remodeled and what properties make them conducive for replication are unknown. Here we show how RNA viruses can manipulate multiple components of the cellular secretory pathway to generate organelles specialized for replication that are distinct in protein and lipid composition from the host cell. Specific viral proteins modulate effector recruitment by Arf1 GTPase and its guanine nucleotide exchange factor GBF1, promoting preferential recruitment of phosphatidylinositol-4-kinase IIIbeta (PI4KIIIbeta) to membranes over coat proteins, yielding uncoated phosphatidylinositol-4-phosphate (PI4P) lipid-enriched organelles. The PI4P-rich lipid microenvironment is essential for both enteroviral and flaviviral RNA replication; PI4KIIIbeta inhibition interferes with this process; and enteroviral RNA polymerases specifically bind PI4P. These findings reveal how RNA viruses can selectively exploit specific elements of the host to form specialized organelles where cellular phosphoinositide lipids are key to regulating viral RNA replication.

Catch and Release of Cytokines Mediated by Tumor Phosphatidylserine Converts Transient Exposure into Long-Lived Inflammation.

Immune cells constantly survey the host for pathogens or tumors and secrete cytokines to alert surrounding cells of these threats. In vivo, activated immune cells secrete cytokines for several hours, yet an acute immune reaction occurs over days. Given these divergent timescales, we addressed how cytokine-responsive cells translate brief cytokine exposure into phenotypic changes that persist over long timescales. We studied melanoma cell responses to transient exposure to the cytokine interferon γ (IFNγ) by combining a systems-scale analysis of gene expression dynamics with computational modeling and experiments. We discovered that IFNγ is captured by phosphatidylserine (PS) on the surface of viable cells both in vitro and in vivo then slowly released to drive long-term transcription of cytokine-response genes. This mechanism introduces an additional function for PS in dynamically regulating inflammation across diverse cancer and primary cell types and has potential to usher in new immunotherapies targeting PS and inflammatory pathways.

An intestinal organoid-based platform that recreates susceptibility to T-cell-mediated tissue injury.

A goal in precision medicine is to use patient-derived material to predict disease course and intervention outcomes. Here, we use mechanistic observations in a preclinical animal model to design an ex vivo platform that recreates genetic susceptibility to T-cell-mediated damage. Intestinal graft-versus-host disease (GVHD) is a life-threatening complication of allogeneic hematopoietic cell transplantation. We found that intestinal GVHD in mice deficient in Atg16L1, an autophagy gene that is polymorphic in humans, is reversed by inhibiting necroptosis. We further show that cocultured allogeneic T cells kill Atg16L1-mutant intestinal organoids from mice, which was associated with an aberrant epithelial interferon signature. Using this information, we demonstrate that pharmacologically inhibiting necroptosis or interferon signaling protects human organoids derived from individuals harboring a common ATG16L1 variant from allogeneic T-cell attack. Our study provides a roadmap for applying findings in animal models to individualized therapy that targets affected tissues.

Diversity-Oriented One-Pot Synthesis to Construct Functionalized Chroman-2-one Derivatives and Other Heterocyclic Compounds.

The asymmetric organocatalyzed diversity-oriented one-pot synthesis has been developed to construct chroman-2-one derivatives and other heterocyclic compounds with excellent efficiency and stereoselectivity. The reactions represent a challenging issue, since it altered the inherent selectivity profiles exhibited by the substrates of 2-hydroxycinnamaldehyde 1 and trans-ß-nitrostyrene 2, which was previously reported as the asymmetric oxa-Michael-Michael cascade to generate chiral chromans. It should be noted that polycyclic O,O-acetal-containing compounds, which are found in numerous natural products and biologically interesting molecules, could also be achieved in good yields with excellent enantioselectivity as a single diastereoisomer with five continuous stereogenic centers.

Intercellular Transmission of Viral Populations with Vesicles.

A common paradigm holds that during cell-to-cell transmission, viruses behave as lone soldiers. Recently, we discovered not only that enteroviruses are transmitted via vesicles as populations of viral particles but also that this type of transmission enhances their infection efficiency (Y. H. Chen et al., Cell 160: 619-630, 2015). This mechanism could be advantageous for the overall fitness of the viral population, promoting genetic interplay by enabling viral quasispecies to collectively infect a susceptible host cell. Here, we discuss these findings in the context of viral pathogenesis and also propose that this novel type of vesicular transmission is widespread among different virus families and includes populations of both viral particles and naked viral genomes.

An interaction between glutathione and the capsid is required for the morphogenesis of C-cluster enteroviruses.

Glutathione (GSH) is the most abundant cellular thiol playing an essential role in preserving a reduced cellular environment. Cellular GSH levels can be efficiently reduced by the GSH biosynthesis inhibitor, L-buthionine sulfoximine (BSO). The aim of our study was to determine the role of GSH in the growth of two C-cluster enteroviruses, poliovirus type 1 (PV1) and coxsackievirus A20 (CAV20). Our results show that the growth of both PV1 and CAV20 is strongly inhibited by BSO and can be partially reversed by the addition of GSH. BSO has no effect on viral protein synthesis or RNA replication but it strikingly reduces the accumulation of 14S pentamers in infected cells. GSH-pull down assays show that GSH directly interacts with capsid precursors and mature virus made in the absence of BSO whereas capsid precursors produced under GSH-depletion do not bind to GSH. In particular, the loss of binding of GSH may debilitate the stability of 14S pentamers, resulting in their failure to assemble into mature virus. Immunofluorescence cell imaging demonstrated that GSH-depletion did not affect the localization of viral capsid proteins to the replication complex. PV1 BSO resistant (BSOr) mutants evolved readily during passaging of the virus in the presence of BSO. Structural analyses revealed that the BSOr mutations, mapping to VP1 and VP3 capsid proteins, are primarily located at protomer/protomer interfaces. BSOr mutations might, in place of GSH, aid the stability of 14S particles that is required for virion maturation. Our observation that BSOr mutants are more heat resistant and need less GSH than wt virus to be protected from heat inactivation suggests that they possess a more stable capsid. We propose that the role of GSH during enterovirus morphogenesis is to stabilize capsid structures by direct interaction with capsid proteins both during and after the formation of mature virus particles.

From racemic precursors to fully stereocontrolled products: one-pot synthesis of chiral α-amino lactones and lactams.

Substituted racemic lactols or cyclic hemiaminals were directly used as nucleophiles in enamine-based asymmetric amination reactions to access enantioenriched α-amino lactones or lactams via a one-pot sequence. The desired products, which are very important building blocks in organic synthesis but difficult to be prepared in the optically enriched form, could be afforded with two stereogenic centers in high yields with excellent enantioselectivities. Moreover, starting from the racemic precursors and catalyzed by the enantiomeric pair of the catalyst, all possible stereoisomeric products were discretely provided only after simple column chromatography. Additionally, this protocol provides facile access to several novel bicyclic carbamates, and such drug-like heterocyclic compounds should be potentially useful in medicinal chemistry.

[Relief of urinary retention after radical hysterectomy for cervical cancer patients by acupressure: a randomized controlled trial].

OBJECTIVE: To study whether acupressure could relieve urinary retention after radical hysterectomy in cervical cancer patients. METHODS: A randomized controlled prospective double-blinded trial was carried out in 107 urinary retention patients undergoing grade III radical hysterectomy. They were assigned to Group A (positive acupoints, 40 cases), Group B (negative acupoints, 32 cases) , and Group C (with no acupoints, 35 cases). All patients received protective 115 000 potassium permanganate sitz bath, 15 - 20 min each time, 3 times per day. Patients in Group A received acupressure at positive points [liniao point and Qihai (RN6)] combined points by syndrome typing [Guanyuan (RN4) , Zhongji (RN3) , Shenshu (BL23) , Zusanli (ST36), Sanyinjiao (SP6), and Taixi (K13)]. Patients in Group B received negative acupressure at sham-acupoints (for adjusting gastrointestinal functions). Patients in Group C only received conventional sitz bath. All medication was performed 3 times per day, 7 days as one therapeutic course, 21 days in total. The residual urine volume was detected. The recovery time for bladder function was recorded. The average residual urine volume was also recorded at day 7, 14, and 21. RESULTS: Compared with Group B and C, the time for ureter retention was shortened for mild and severe CKD patients in Group A (P <0. 01). The residual urine volume was also lessened for mild and severe CKD patients in Group A at day 7, 14, and 21 (P <0.01). CONCLUSION: Cervical cancer patients could relieve urinary retention by self-acupressure after radical hysterectomy.

Pure NOTES transvaginal appendectomy with gasless laparoscopy.

BACKGROUND: The vagina is the most widely used approach to natural orifice transluminal endoscopic surgery. However, a gas leak can significantly affect transvaginal operations during pneumoperitoneum laparoscopy. We tried to establish the proper technique for transvaginal appendectomy under gasless laparoscopy. MATERIALS AND METHODS: Five patients with chronic appendicitis were selected to receive gasless laparoscopic transvaginal appendectomy with concurrent vaginal hysterectomy. An abdominal wall-lifting device was applied after removal of the uterus, and the appendix was removed transvaginally. Clinical data such as operative duration, bleeding volume, morbidity, and hospital stay duration were analyzed. RESULTS: All procedures were performed successfully, without intraoperative or major postoperative complications. The appendectomy portion of the procedure took approximately 20-30 minutes, with minimal blood loss. All patients were discharged, scar-free, 3 d after surgery. CONCLUSIONS: Transvaginal appendectomy with gasless laparoscopy after vaginal hysterectomy appears to be a feasible and safe modification of established techniques, with acceptable outcomes.

Transvaginal laparoscopic appendectomy simultaneously with vaginal hysterectomy: initial experience of 10 cases.

BACKGROUND: Natural orifice transluminal endoscopic surgery (NOTES) involves the introduction of instruments through a natural orifice into the peritoneal cavity to perform surgical interventions. The vagina is the most widely used approach to NOTES. We report the utilization of the vaginal opening at the time of vaginal hysterectomy as a natural orifice for laparoscopic appendectomy. MATERIAL AND METHODS: We reviewed cases of 10 patients with chronic appendicitis who underwent transvaginal laparoscopic appendectomy simultaneously with vaginal hysterectomy. A laparoscopic approach was established after removal of the uterus, and the appendix was removed transvaginally. Among the 10 cases, 5 were conducted under gasless laparoscopy by using a simple abdominal wall-lifting instrument. RESULTS: All procedures were performed successfully without intraoperative or major postoperative complications. The appendectomy portion of the procedure took approximately 21 minutes to 34 minutes. All patients were discharged less than 4 days after surgery, without external scars. CONCLUSIONS: Transvaginal appendectomy with rigid laparoscopic instruments following vaginal hysterectomy appears to be a feasible and safe modification of established techniques, with acceptable outcomes.

Silencing Cofilin-1 blocks PDGF-induced proliferation in eutopic endometrium of endometriosis patients.

Platelet-derived growth factor (PDGF) is well known to induce proliferation in variety of cells. The aim of this study was to investigate whether there is a correlation between the expression of Cofilin-1 (CFL1) and the proliferation of eutopic endometrium stromal cells (ESC) in response to PDGF stimulation. Results show that PDGF induced the expression of CFL1 in ESC and promoted proliferation of ESC significantly in a time- or dose-dependent manner. After silencing CFL1, the effect of PDGF on promoting ESC proliferation was significantly decreased. These data demonstrate that PDGF can induce CFL1 expression in ESC. Silencing CFL1 blocks PDGF-induced proliferation in ESC.

Asymmetric iminium ion-catalyzed conjugate addition of 2-hydroxycinnamaldehydes and 2-oxocarboxylic esters: synthesis of chiral polysubstituted bridged bicyclic ketals.

A highly regio-, chemo-, and stereoselective cascade process initiated by enantioselective iminium-catalyzed conjugate addition of 2-hydroxycinnamaldehydes and 2-oxocarboxylic esters is presented. Normal cinnamaldehydes are not reactive under the same reaction conditions. Bridged bicyclic ketals rather than acetals bearing stereocenters on both the bridge carbon and bridgehead ketal carbon are synthesized.

Antimicrobial overproduction sustains intestinal inflammation by inhibiting Enterococcus colonization.

Loss of antimicrobial proteins such as REG3 family members compromises the integrity of the intestinal barrier. Here, we demonstrate that overproduction of REG3 proteins can also be detrimental by reducing a protective species in the microbiota. Patients with inflammatory bowel disease (IBD) experiencing flares displayed heightened levels of secreted REG3 proteins that mediated depletion of Enterococcus faecium ( Efm ) from the gut microbiota. Efm inoculation of mice ameliorated intestinal inflammation through activation of the innate immune receptor NOD2, which was associated with the bacterial DL-endopeptidase SagA. Microbiota sensing by NOD2 in myeloid cells mediated IL-1ß secretion and increased the proportion of IL-22-producing CD4 + T helper cells and innate lymphoid cells. Finally, Efm was unable to protect mice carrying a NOD2 gene variant commonly found in IBD patients. Our findings demonstrate that inflammation self-perpetuates by causing aberrant antimicrobial activity that disrupts symbiotic relationships with gut microbes.

Antimicrobial overproduction sustains intestinal inflammation by inhibiting Enterococcus colonization.

Loss of antimicrobial proteins such as REG3 family members compromises the integrity of the intestinal barrier. Here, we demonstrate that overproduction of REG3 proteins can also be detrimental by reducing a protective species in the microbiota. Patients with inflammatory bowel disease (IBD) experiencing flares displayed heightened levels of secreted REG3 proteins that mediated depletion of Enterococcus faecium (Efm) from the gut microbiota. Efm inoculation of mice ameliorated intestinal inflammation through activation of the innate immune receptor NOD2, which was associated with the bacterial DL-endopeptidase SagA that generates NOD2-stimulating muropeptides. NOD2 activation in myeloid cells induced interleukin-1ß (IL-1ß) secretion to increase the proportion of IL-22-producing CD4+ T helper cells and innate lymphoid cells that promote tissue repair. Finally, Efm was unable to protect mice carrying a NOD2 gene variant commonly found in IBD patients. Our findings demonstrate that inflammation self-perpetuates by causing aberrant antimicrobial activity that disrupts symbiotic relationships with gut microbes.

Genetic and Environmental interactions contribute to immune variation in rewilded mice.

The relative and synergistic contributions of genetics and environment to inter-individual immune response variation remain unclear, despite its implications for understanding both evolutionary biology and medicine. Here, we quantify interactive effects of genotype and environment on immune traits by investigating three inbred mouse strains rewilded in an outdoor enclosure and infected with the parasite, Trichuris muris. Whereas cytokine response heterogeneity was primarily driven by genotype, cellular composition heterogeneity was shaped by interactions between genotype and environment. Notably, genetic differences under laboratory conditions can be decreased following rewilding, and variation in T cell markers are more driven by genetics, whereas B cell markers are driven more by environment. Importantly, variation in worm burden is associated with measures of immune variation, as well as genetics and environment. These results indicate that nonheritable influences interact with genetic factors to shape immune variation, with synergistic impacts on the deployment and evolution of defense mechanisms.