Covid-19 Interstitial Pneumonia: Histological and Immunohistochemical Features on Cryobiopsies
Respiration; international review of thoracic diseases
Doglioni, C;Ravaglia, C;Chilosi, M;Rossi, G;Dubini, A;Pedica, F;Piciucchi, S;Vizzuso, A;Stella, F;Maitan, S;Agnoletti, V;Puglisi, S;Poletti, G;Sambri, V;Pizzolo, G;Bronte, V;Wells, AU;Poletti, V;
PMID: 33725700 | DOI: 10.1159/000514822
The pathogenetic steps leading to Covid-19 interstitial pneumonia remain to be clarified. Most postmortem studies to date reveal diffuse alveolar damage as the most relevant histologic pattern. Antemortem lung biopsy may however provide more precise data regarding the earlier stages of the disease, providing a basis for novel treatment approaches. To ascertain the morphological and immunohistochemical features of lung samples obtained in patients with moderate Covid-19 pneumonia. Transbronchial lung cryobiopsy was carried out in 12 Covid-19 patients within 20 days of symptom onset. Histopathologic changes included spots of patchy acute lung injury with alveolar type II cell hyperplasia, with no evidence of hyaline membranes. Strong nuclear expression of phosphorylated STAT3 was observed in >50% of AECII. Interalveolar capillaries showed enlarged lumen and were in part arranged in superposed rows. Pulmonary venules were characterized by luminal enlargement, thickened walls, and perivascular CD4+ T-cell infiltration. A strong nuclear expression of phosphorylated STAT3, associated with PD-L1 and IDO expression, was observed in endothelial cells of venules and interstitial capillaries. Alveolar spaces macrophages exhibited a peculiar phenotype (CD68, CD11c, CD14, CD205, CD206, CD123/IL3AR, and PD-L1). Morphologically distinct features were identified in early stages of Covid-19 pneumonia, with epithelial and endothelial cell abnormalities different from either classical interstitial lung diseases or diffuse alveolar damage. Alveolar type II cell hyperplasia was a prominent event in the majority of cases. Inflammatory cells expressed peculiar phenotypes. No evidence of hyaline membranes and endothelial changes characterized by IDO expression might in part explain the compliance and the characteristic pulmonary vasoplegia observed in less-advanced Covid-19 pneumonia.
Myocardial TGFβ2 Is Required for Atrioventricular Cushion Remodeling and Myocardial Development
Journal of Cardiovascular Development and Disease
Bhattacharya, A;Al-Sammarraie, N;Gebere, M;Johnson, J;Eberth, J;Azhar, M;
| DOI: 10.3390/jcdd8030026
Among the three transforming growth factor beta (TGFβ) ligands, TGFβ2 is essential for heart development and is produced by multiple cell types, including myocardium. Heterozygous mutations in TGFB2 in patients of connective tissue disorders result in congenital heart defects and adult valve malformations, including mitral valve prolapse (MVP) with or without regurgitation. Tgfb2 germline knockout fetuses exhibit multiple cardiac defects but the role of myocardial-TGFβ2 in heart development is yet to be elucidated. Here, myocardial Tgfb2 conditional knockout (CKO) embryos were generated by crossing Tgfb2flox mice with Tgfb2+/−; cTntCre mice. Tgfb2flox/− embryos were normal, viable. Cell fate mapping was done using dual-fluorescent mT/mG+/− mice. Cre-mediated Tgfb2 deletion was assessed by genomic PCR. RNAscope in situ hybridization was used to detect the loss of myocardial Tgfb2 expression. Histological, morphometric, immunohistochemical, and in situ hybridization analyses of CKOs and littermate controls at different stages of heart development (E12.5–E18.5) were used to determine the role of myocardium-derived TGFβ2 in atrioventricular (AV) cushion remodeling and myocardial development. CKOs exhibit a thin ventricular myocardium, AV cushion remodeling defects and developed incomplete AV septation defects. The loss of myocardial Tgfb2 resulted in impaired cushion maturation and dysregulated cell death. Phosphorylated SMAD2, a surrogate for TGFβ signaling, was “paradoxically” increased in both AV cushion mesenchyme and ventricular myocardium in the CKOs. Our results indicate that TGFβ2 produced by cardiomyocytes acting as cells autonomously on myocardium and via paracrine signaling on AV cushions are required for heart development.
Mechanisms and regulation of IL-22-mediated intestinal epithelial homeostasis and repair
Patnaude, L;Mayo, M;Mario, R;Wu, X;Knight, H;Creamer, K;Wilson, S;Pivorunas, V;Karman, J;Phillips, L;Dunstan, R;Kamath, RV;McRae, B;Terrillon, S;
PMID: 33581125 | DOI: 10.1016/j.lfs.2021.119195
Ulcerative colitis and Crohn's disease, collectively known as inflammatory bowel disease (IBD), are chronic inflammatory disorders of the intestine for which key elements in disease initiation and perpetuation are defects in epithelial barrier integrity. Achieving mucosal healing is essential to ameliorate disease outcome and so new therapies leading to epithelial homeostasis and repair are under investigation. This study was designed to determine the mechanisms by which IL-22 regulates intestinal epithelial cell function. Human intestinal organoids and resections, as well as mice were used to evaluate the effect of IL-22 on stem cell expansion, proliferation and expression of mucus components. IL-22 effect on barrier function was assessed in polarized T-84 cell monolayers. Butyrate co-treatments and organoid co-cultures with immune cells were performed to monitor the impact of microbial-derived metabolites and inflammatory environments on IL-22 responses. IL-22 led to epithelial stem cell expansion, proliferation, barrier dysfunction and anti-microbial peptide production in human and mouse models evaluated. IL-22 also altered the mucus layer by inducing an increase in membrane mucus but a decrease in secreted mucus and goblet cell content. IL-22 had the same effect on anti-microbial peptides and membrane mucus in both healthy and IBD human samples. In contrast, this IL-22-associated epithelial phenotype was different when treatments were performed in presence of butyrate and organoids co-cultured with immune cells. Our data indicate that IL-22 promotes epithelial regeneration, innate defense and membrane mucus production, strongly supporting the potential clinical utility of IL-22 as a mucosal healing therapy in IBD.
Rad-GTPase contributes to heart rate via L-type calcium channel regulation
Journal of molecular and cellular cardiology
Levitan, BM;Ahern, BM;Aloysius, A;Brown, L;Wen, Y;Andres, DA;Satin, J;
PMID: 33556393 | DOI: 10.1016/j.yjmcc.2021.01.005
Sinoatrial node cardiomyocytes (SANcm) possess automatic, rhythmic electrical activity. SAN rate is influenced by autonomic nervous system input, including sympathetic nerve increases of heart rate (HR) via activation of β-adrenergic receptor signaling cascade (β-AR). L-type calcium channel (LTCC) activity contributes to membrane depolarization and is a central target of β-AR signaling. Recent studies revealed that the small G-protein Rad plays a central role in β-adrenergic receptor directed modulation of LTCC. These studies have identified a conserved mechanism in which β-AR stimulation results in PKA-dependent Rad phosphorylation: depletion of Rad from the LTCC complex, which is proposed to relieve the constitutive inhibition of CaV1.2 imposed by Rad association. Here, using a transgenic mouse model permitting conditional cardiomyocyte selective Rad ablation, we examine the contribution of Rad to the control of SANcm LTCC current (ICa,L) and sinus rhythm. Single cell analysis from a recent published database indicates that Rad is expressed in SANcm, and we show that SANcm ICa,L was significantly increased in dispersed SANcm following Rad silencing compared to those from CTRL hearts. Moreover, cRadKO SANcm ICa,L was not further increased with β-AR agonists. We also evaluated heart rhythm in vivo using radiotelemetered ECG recordings in ambulating mice. In vivo, intrinsic HR is significantly elevated in cRadKO. During the sleep phase cRadKO also show elevated HR, and during the active phase there is no significant difference. Rad-deletion had no significant effect on heart rate variability. These results are consistent with Rad governing LTCC function under relatively low sympathetic drive conditions to contribute to slower HR during the diurnal sleep phase HR. In the absence of Rad, the tonic modulated SANcm ICa,L promotes elevated sinus HR. Future novel therapeutics for bradycardia targeting Rad - LTCC can thus elevate HR while retaining βAR responsiveness.
Toll-like receptor 5 knock-out mice exhibit a specific low level of anxiety
Brain, behavior, and immunity
Hamieh, AM;Mallaret, G;Meleine, M;Lashermes, A;Roumeau, S;Boudieu, L;Barbier, J;Aissouni, Y;Ardid, D;Gewirtz, AT;Carvalho, FA;Marchand, F;
PMID: 33516921 | DOI: 10.1016/j.bbi.2021.01.020
While toll-like receptors (TLRs), which mediate innate immunity, are known to play an important role in host defense, recent work suggest their involvement in some integrated behaviors, including anxiety, depressive and cognitive functions. Here, we investigated the potential involvement of the flagellin receptor, TLR5, in anxiety, depression and cognitive behaviors using male TLR5 knock-out (KO) mice. We aobserved a specific low level of basal anxiety in TLR5 KO mice with an alteration of the hypothalamo-pituitary axis (HPA) response to acute restraint stress, illustrated by a decrease of both plasma corticosterone level and c-fos expression in the hypothalamic paraventricular nucleus where TLR5 was expressed, compared to WT littermates. However, depression and cognitive-related behaviors were not different between TLR5 KO and WT mice. Nor there were significant changes in the expression of some cytokines (IL-6, IL-10 and TNF-α) and other TLRs (TLR2, TLR3 and TLR4) in the prefrontal cortex, amygdala and hippocampus of TLR5 KO mice compared to WT mice. Moreover, mRNA expression of BDNF and glucocorticoid receptors in the hippocampus and amygdala, respectively, was not different. Finally, acute intracerebroventricular administration of flagellin, a specific TLR5 agonist, or chronic neomycin treatment did not exhibit a significant main effect, only a significant main effect of genotype was observed between TLR5 KO and WT mice. Together, those findings suggest a previously undescribed and specific role of TLR5 in anxiety and open original prospects in our understanding of the brain-gut axis function.
Oncogenic HPV promotes the expression of the long noncoding RNA lnc-FANCI-2 through E7 and YY1
Proceedings of the National Academy of Sciences of the United States of America
Liu, H;Xu, J;Yang, Y;Wang, X;Wu, E;Majerciak, V;Zhang, T;Steenbergen, RDM;Wang, HK;Banerjee, NS;Li, Y;Lu, W;Meyers, C;Zhu, J;Xie, X;Chow, LT;Zheng, ZM;
PMID: 33436409 | DOI: 10.1073/pnas.2014195118
Long noncoding RNAs (lncRNAs) play diverse roles in biological processes, but their expression profiles and functions in cervical carcinogenesis remain unknown. By RNA-sequencing (RNA-seq) analyses of 18 clinical specimens and selective validation by RT-qPCR analyses of 72 clinical samples, we provide evidence that, relative to normal cervical tissues, 194 lncRNAs are differentially regulated in high-risk (HR)-HPV infection along with cervical lesion progression. One such lncRNA, lnc-FANCI-2, is extensively characterized because it is expressed from a genomic locus adjacent to the FANCI gene encoding an important DNA repair factor. Both genes are up-regulated in HPV lesions and in in vitro model systems of HR-HPV18 infection. We observe a moderate reciprocal regulation of lnc-FANCI-2 and FANCI in cervical cancer CaSki cells. In these cells, lnc-FANCI-2 is transcribed from two alternative promoters, alternatively spliced, and polyadenylated at one of two alternative poly(A) sites. About 10 copies of lnc-FANCI-2 per cell are detected preferentially in the cytoplasm. Mechanistically, HR-HPVs, but not low-risk (LR)-HPV oncogenes induce lnc-FANCI-2 in primary and immortalized human keratinocytes. The induction is mediated primarily by E7, and to a lesser extent by E6, mostly independent of p53/E6AP and pRb/E2F. We show that YY1 interacts with an E7 CR3 core motif and transactivates the promoter of lnc-FANCI-2 by binding to two critical YY1-binding motifs. Moreover, HPV18 increases YY1 expression by reducing miR-29a, which targets the 3' untranslated region of YY1 mRNA. These data have provided insights into the mechanisms of how HR-HPV infections contribute to cervical carcinogenesis.
Effects of Vitamin D Supplementation on a Diet‐induced Obesity Model: Cognitive Behavior
Kozlova, E;Denys, M;Carabelli, B;Bishay, A;
| DOI: 10.1096/fasebj.2021.35.S1.02887
Obesity is a disease that affects 1/3 of the US population that could lead to several comorbidities. Obesity induces cognitive and behavioral impairment. Low plasma vitamin D levels are associated with increased body mass index (BMI). Therefore, vitamin D supplementation has shown benefits in BMI, glucose homeostasis and cognitive/behavioral function; however, contradictory data exists in animal models and remains poorly studied. Obesity in males increases 5.7-fold the risk for severe complications and death due to SARSCoV-2. Brain RAS activity, especially activation of the Angiotensin II receptor (AT1R), has been implicated in cognitive impairment and may participate in persistent neurological symptoms seen in 1 in 3 severe COVID-19 cases, i.e., disorientation, inattention and ataxia. Supplementation with Vitamin D (VitD), known to ameliorate respiratory infections and thromboembolism, may protect against COVID symptoms by increasing ACE2 and Masr expression. To generate a diet-induced obesity (DIO) model, C57Bl6/J male mice (7 wks of age) were randomly assigned to 3 groups (n=10/group) and were fed ad libitum with a) chow diet (CD), b) lard-based high-fat diet (HFD, 60% fat; D12492; Research diet, New Brunswick, NJ), or c) HFD supplemented with vitamin D (60% fat plus 15,000 IU/kg diet, HVitD). Behavioral and metabolic endpoints were measured starting at 7 wks on diet. The HFD diet was effective in generating DIO vs CD despite equivalent food intake consumption on a kcal-basis. Body composition analysis (EchoMRI) showed increased fat mass in HFD and HVitD when compared to CD. Contrary to our hypothesis, ip glucose (0.25 mg/kg) caused greater glucose intolerance in HVitD relative to HFD at 15 (P
Richer, G;Goossens, E;Baert, Y;
| DOI: 10.1093/humrep/deac107.084/44305947/deac107.084
Study question: Can our newly developed testicular organoid (TO) growth platform advance the robustness of murine TOs? Summary answer: The platform resulted in more consistent TO histology. Moreover, improved germ cell survival was observed after a two-week culture with numbers comparable to fresh samples. What is known already: Organ cultures have traditionally been used for invitro spermatogenesis (IVS) in rodents because they best preserve the testicular architecture which is pivotal in achieving IVS. However, organ cultures do not offer the ability to access and manipulate single cells, making it an inefficient model for mechanistic studies. Organoids made from testicular cell suspensions offer these features. Although TO cultures can result in organoids with compartmentalized testicular architecture, histological heterogeneity between individual TOs limits reproducibility of the results, offering unreliable readouts. Moreover, germ cell loss is characteristic during the reorganization phase. Study design, size, duration: Here, we tested a new TO growth platform. Firstly, the focus was put on improving germ cell survival in TOs during tubulogenesis in the first two weeks of culture. For this, four different growth media (A-D), supplemented with other combinations or concentrations of growth factors, were compared. Next, five cell seeding densities (I-V) were tested for their ability to recreate the testicular architecture in TOs in the selected culture media. Participants/materials, setting, methods: Testicular cells from 5 days old C57BL/6J mice were grown in our TO platform with alpha-MEM-based medium, previously found to support TO generation in mice (medium A). Three additional conditions were tested in their ability to improve germ cell survival during tubulogenesis (B-D). Finally, the ideal cell density (I-V) was determined based on histological resemblance to native tissue: one tubule-like structure and surrounding interstitium. Cellular reorganization and germ cell maintenance were characterized by (immuno)histochemistry. Main results and the role of chance: During short-term cultures of 2 weeks, testicular cells self-assembled and compacted into organoids in our platform. Interestingly, media B and D resulted in the highest amount of germ cells (p < 0.05), comparable to the fresh control. Particularly TOs cultured in medium D also exhibited the largest surface area, indicative for better in-vitro growth. Finally, TOs that were cultured in condition D had the best histology when grown at cell density IV and V (p < 0.05). Limitations, reasons for caution: Candidate factors have to be tested in their ability to elevate the meiotic blockage of germ cells typically observed in organ culture, but also in TOs. Finally, results obtained with rodents remain to be confirmed in further human studies. Wider implications of the findings: . The opportunities TOs offer to manipulate cells (genetic modification, inclusion and exclusion) are essential for the study of male infertility and the search for potential therapies. Moreover, they permit high-throughput screening of chemicals, thereby substantially reducing the number of animals for the high demanding reproductive toxicity and drug discovery studies.
Activation of GABAergic Neurons in the Rostromedial Tegmental Nucleus and Other Brainstem Regions Promotes Sedation and Facilitates Sevoflurane Anesthesia in Mice
Vlasov, K;Pei, J;Nehs, CJ;Guidera, JA;Zhang, ER;Kenny, JD;Houle, TT;Brenner, GJ;Taylor, NE;Solt, K;
PMID: 33560660 | DOI: 10.1213/ANE.0000000000005387
Many general anesthetics potentiate gamma-aminobutyric acid (GABA) A receptors but their neuroanatomic sites of action are less clear. GABAergic neurons in the rostromedial tegmental nucleus (RMTg) send inhibitory projections to multiple arousal-promoting nuclei, but the role of these neurons in modulating consciousness is unknown. In this study, designer receptors exclusively activated by designer drugs (DREADDs) were targeted to RMTg GABAergic neurons of Vgat-ires-Cre mice. DREADDs expression was found in the RMTg and other brainstem regions. Activation of these neurons decreased movement and exploratory behavior, impaired motor coordination, induced electroencephalogram (EEG) oscillations resembling nonrapid eye movement (NREM) sleep without loss of righting and reduced the dose requirement for sevoflurane-induced unconsciousness. These results suggest that GABAergic neurons in the RMTg and other brainstem regions promote sedation and facilitate sevoflurane-induced unconsciousness.
Olson, ND;Wagner, J;Dwarshuis, N;Miga, KH;Sedlazeck, FJ;Salit, M;Zook, JM;
PMID: 37059810 | DOI: 10.1038/s41576-023-00590-0
Genetic variant calling from DNA sequencing has enabled understanding of germline variation in hundreds of thousands of humans. Sequencing technologies and variant-calling methods have advanced rapidly, routinely providing reliable variant calls in most of the human genome. We describe how advances in long reads, deep learning, de novo assembly and pangenomes have expanded access to variant calls in increasingly challenging, repetitive genomic regions, including medically relevant regions, and how new benchmark sets and benchmarking methods illuminate their strengths and limitations. Finally, we explore the possible future of more complete characterization of human genome variation in light of the recent completion of a telomere-to-telomere human genome reference assembly and human pangenomes, and we consider the innovations needed to benchmark their newly accessible repetitive regions and complex variants.
Seminars in immunopathology
Glasson, Y;Chépeaux, LA;Dumé, AS;Lafont, V;Faget, J;Bonnefoy, N;Michaud, HA;
PMID: 36598557 | DOI: 10.1007/s00281-022-00978-w
Solid tumors have a dynamic ecosystem in which malignant and non-malignant (endothelial, stromal, and immune) cell types constantly interact. Importantly, the abundance, localization, and functional orientation of each cell component within the tumor microenvironment vary significantly over time and in response to treatment. Such intratumoral heterogeneity influences the tumor course and its sensitivity to treatments. Recently, high-dimensional imaging mass cytometry (IMC) has been developed to explore the tumor ecosystem at the single-cell level. In the last years, several studies demonstrated that IMC is a powerful tool to decipher the tumor complexity. In this review, we summarize the potential of this technology and how it may be useful for cancer research (from preclinical to clinical studies).
Ellinghaus, P;Neureiter, D;Nogai, H;Stintzing, S;Ocker, M;
PMID: 36231142 | DOI: 10.3390/cells11193180
Inhibitors of fibroblast growth factor receptor (FGFR) signaling have been investigated in various human cancer diseases. Recently, the first compounds received FDA approval in biomarker-selected patient populations. Different approaches and technologies have been applied in clinical trials, ranging from protein (immunohistochemistry) to mRNA expression (e.g., RNA in situ hybridization) and to detection of various DNA alterations (e.g., copy number variations, mutations, gene fusions). We review, here, the advantages and limitations of the different technologies and discuss the importance of tissue and disease context in identifying the best predictive biomarker for FGFR targeting therapies.