The recent emergence of the SARS-CoV-2 Omicron variant of concern (VOC) containing a heavily mutated spike protein capable of escaping preexisting immunity identifies a continued need for interventional measures. Molnupiravir (MK-4482), an orally administered nucleoside analog, has demonstrated efficacy against earlier SARS-CoV-2 lineages and was recently approved for SARS-CoV-2 infections in high-risk adults. Here we assessed the efficacy of MK-4482 against the earlier Alpha, Beta and Delta VOCs and Omicron in the hamster COVID-19 model. Omicron replication and associated lung disease in vehicle treated hamsters was reduced compared to the earlier VOCs. MK-4482 treatment inhibited virus replication in the lungs of Alpha, Beta and Delta VOC infected hamsters. Importantly, MK-4482 profoundly inhibited virus replication in the upper and lower respiratory tract of hamsters infected with the Omicron VOC. Consistent with its mutagenic mechanism, MK-4482 treatment had a more pronounced inhibitory effect on infectious titers compared to viral RNA genome load. Histopathologic analysis showed that MK-4482 treatment caused a concomitant reduction in the level of lung disease and viral antigen load in infected hamsters across all VOCs examined. Together, our data indicate the potential of MK-4482 as an effective antiviral against known SARS-CoV-2 VOCs, especially Omicron, and likely future SARS-CoV-2 variants.
Kyle Rosenke, Atsushi Okumura, Matthew C. Lewis, Friederike Feldmann, Kimberly Meade-White, William F. Bohler, Amanda J. Griffin, Rebecca Rosenke, Carl Shaia, Michael A. Jarvis, Heinz Feldmann
Understanding the reorganization of neural circuits spared after spinal cord injury in the motor cortex and spinal cord would provide insight for developing therapeutics. Using optogenetic mapping we demonstrate a transhemispheric recruitment of neural circuits in the contralateral cortical M1/M2 area to improve the impaired forelimb function after a cervical 5 right-sided hemisection in mice, a model mimicking the human Brown-Séquard syndrome. This cortical reorganization can be elicited by a selective cortical optogenetic neuromodulation paradigm. Areas of whisker, jaw, and neck, together with the rostral forelimb area, on the motor cortex ipsilateral to the lesion are engaged to control the ipsilesional forelimb in both stimulation and non-stimulation groups at 8 weeks post-injury. However, significant functional benefits are only seen in the stimulation group. Using anterograde tracer, we further reveal a robust sprouting of the intact corticospinal tract in the spinal cord of those animals receiving optogenetic stimulation. The intraspinal cortical spinal axonal sprouting corelates with the forelimb functional recovery. Thus, specific neuromodulation of the cortical neural circuits induces massive neural reorganization both in the motor cortex and spinal cord, constructing an alternative motor pathway in restoring impaired forelimb function.
Wei Wu, Tyler Nguyen, Josue D. Ordaz, Yi Ping Zhang, Nai-Kui Liu, Xinhua Hu, Yuxiang Liu, Xingjie Ping, Qi Han, Xiangbing Wu, Wenrui Qu, Sujuan Gao, Christopher B. Shields, Xiaoming Jin, Xiao-Ming Xu
Tertiary lymphoid structures (TLSs) are transient ectopic lymphoid aggregates whose formation might be caused by chronic inflammation states, such as cancer. However, how TLSs are induced in the tumor microenvironment (TME) and how they affect patient survival are not well understood. We investigated TLS distribution in relation to tumor infiltrating lymphocytes (TILs) and related gene expression in high grade serous ovarian cancer (HGSC) specimens. CXCL13 gene expression correlated with TLS presence and the infiltration of T cells and B cells, and was a favorable prognostic factor for HGSC patients. Coexistence of CD8+ T cells and B-cell lineages in the TME significantly improved the prognosis of HGSC and was correlated with the presence of TLSs. CXCL13 expression was predominantly coincident with CD4+ T cells in TLSs and CD8+ T cells in TILs, and shifted from CD4+ T cells to CD21+ follicular dendritic cells as TLS matured. In a mouse ovarian cancer model, recombinant CXCL13 induced TLSs and enhanced survival by the infiltration of CD8+ T cells. These results suggest that TLS formation was associated with CXCL13-producing CD4+ T cells and that TLSs facilitated the coordinated antitumor response of cellular and humoral immunity in ovarian cancer.
Masayo Ukita, Junzo Hamanishi, Hiroyuki Yoshitomi, Koji Yamanoi, Shiro Takamatsu, Akihiko Ueda, Haruka Suzuki, Yuko Hosoe, Yoko Furutake, Mana Taki, Kaoru Abiko, Ken Yamaguchi, Hidekatsu Nakai, Tsukasa Baba, Noriomi Matsumura, Akihiko Yoshizawa, Hideki Ueno, Masaki Mandai
Nontuberculous mycobacteria (NTM) are an increasingly common cause of respiratory infection in people with cystic fibrosis (PwCF). Relative to those with no history of NTM infection (CF-NTMNEG), PwCF and a history of NTM infection (CF-NTMPOS) are more likely to develop severe lung disease and experience complications over the course of treatment. In other mycobacterial infections (e.g. tuberculosis), an overexuberant immune response causes pathology and compromises organ function; however, since the immune profiles of CF-NTMPOS and CF-NTMNEG airways are largely unexplored, it is unknown which if any immune responses distinguish these cohorts or concentrate in damaged tissues. Here we evaluated lung lobe-specific immune profiles of three cohorts (CF-NTMPOS, CF-NTMNEG, and non-CF adults) and found that CF-NTMPOS airways are distinguished by a hyper-inflammatory cytokine profile. Importantly, the CF-NTMPOS airway immune profile was dominated by B cells, classical macrophages and the cytokines which support their accumulation. These and other immunological differences between cohorts, including the near absence of NK cells and complement pathway members, were enriched in the most damaged lung lobes. The implications of these findings for our understanding of lung disease in PwCF are discussed, as are how they may inform the development of host-directed therapies to improve NTM disease treatment.
Don Hayes, Jr., Rajni Kant Shukla, Yizi Cheng, Emrah Gecili, Marlena R. Merling, Rhonda D. Szczesniak, Assem G Ziady, Jason C. Woods, Luanne Hall-Stoodley, Namal P.M. Liyanage, Richard T. Robinson
We have previously demonstrated that active immunization with the apolipoprotein B-100 (ApoB-100) peptide P210 reduces experimental atherosclerosis. To advance this immunization strategy to future clinical testing, we explored the possibility of delivering P210 as an antigen using nanoparticles, given this approach has now been used clinically. To that end, we first charactered the responses of T cells to P210 using PBMCs from human subjects with atherosclerotic cardiovascular disease (ASCVD). We then investigated the use of P210 in self-assembling peptide amphiphile micelles (P210-PAM) as a vaccine formulation to reduce atherosclerosis in ApoE-/- mice and its potential mechanisms of action. We also generated and characterized a humanized mouse model with chimeric HLA-A*02:01/Kb in ApoE-/- background to test the efficacy of P210-PAM immunization as a bridge for future clinical testing. P210 provoked T cell activation and memory response in PBMCs of human subjects with ASCVD. Dendritic cell uptake of P210-PAM and its co-staining with MHC-I molecules supported its use as a vaccine formulation. In ApoE-/- mice, immunization with P210-PAM dampened P210-specific CD4+ T cell proliferative response and CD8+ T cell cytolytic response, modulated macrophage phenotype, and significantly reduced aortic atherosclerosis. Potential clinical relevance of P210-PAM immunization was demonstrated by reduced atherosclerosis in the humanized ApoE-/- mouse model expressing chimeric HLA-A*02:01/Kb. Taken together, our data supports the experimental and translational use of P210-PAM as a potential vaccine candidate against human ASCVD.
Kuang-Yuh Chyu, Xiaoning Zhao, Jianchang Zhou, Paul C. Dimayuga, Nicole W.M. Lio, Bojan Cercek, Noah T. Trac, Eun Ji Chung, Prediman K. Shah
Rearrangements that drive ectopic MEF2C expression have recurrently been found in human early thymocyte progenitor acute lymphoblastic leukemia (ETP-ALL) patients. Here we show high levels of MEF2C expression in ETP-ALL patients. Using both in vivo and in vitro models of ETP-ALL, we demonstrate that elevated MEF2C expression blocks NOTCH-induced T cell differentiation while promoting a B-lineage program. MEF2C activates a B cell transcriptional program in addition to RUNX1, GATA3 and LMO2, upregulates the IL7R and boosts cell survival by upregulation of BCL2. MEF2C and the Notch pathway therefore demarcate opposite regulators of B- or T-lineage choices, respectively. Enforced MEF2C expression in mouse or human progenitor cells effectively blocks early T cell differentiation and promotes the development of bi-phenotypic lymphoid tumors that co-express CD3 and CD19, resembling human mixed phenotype acute leukemia (MPAL). SIK inhibitors impair MEF2C activity and alleviate the T cell development block. Importantly, this sensitizes cells to prednisolone treatment. Therefore, SIK inhibiting compounds such as dasatinib are potentially a valuable addition to standard chemotherapy for human ETP-ALL.
Kirsten Canté-Barrett, Mariska T. Meijer, Valentina Cordo', Rico Hagelaar, Wentao Yang, Jiyang Yu, Willem K. Smits, Marloes E. Nulle, Joris P. Jansen, Rob Pieters, Jun J. Yang, Jody J. Haigh, Steven Goossens, Jules P.P. Meijerink
People living with multiple sclerosis (MS) experience episodic central nervous system (CNS) white matter lesions instigated by autoreactive T cells. With age, MS patients show evidence of grey matter demyelination and experience devastating non-remitting symptomology. What drives progression is unclear and has been hampered by the lack of suitable animal models. Here we show that passive experimental autoimmune encephalomyelitis (EAE) induced by an adoptive transfer of young Th17 cells induces a non-remitting clinical phenotype that is associated with persistent leptomeningeal inflammation and cortical pathology in old, but not young SJL/J mice. While the quantity and quality of T cells did not differ in the brains of old vs young EAE mice, an increase in neutrophils and a decrease in B cells was observed in the brains of old mice. Neutrophils were also found in the leptomeninges of a subset of progressive MS patient brains that showed evidence of leptomeningeal inflammation and subpial cortical demyelination. Taken together, our data show that while Th17 cells initiate CNS inflammation, subsequent clinical symptoms and grey matter pathology are dictated by age and associated with other immune cells such as neutrophils.
Michelle Zuo, Naomi M Fettig, Louis-Philippe Bernier, Elisabeth Pössnecker, Shoshana Spring, Annie Pu, Xianjie I. Ma, Dennis S.W. Lee, Lesley A. Ward, Anshu Sharma, Jens Kuhle, John G. Sled, Anne-Katrin Pröbstel, Brian A. MacVicar, Lisa C. Osborne, Jennifer L. Gommerman, Valeria Ramaglia
Faecalibacterium prausnitzii (F. prausnitzii), a dominant bacterium of the human microbiota, is decreased in patients with inflammatory bowel diseases (IBD) and exhibits anti-inflammatory effects. In human, colonic lamina propria contains IL-10-secreting, Foxp3-negative regulatory T cells (Treg) characterized by a double expression of CD4 and CD8α (DP8α) and a specificity for F. prausnitzii. This Treg subset is decreased in IBD. The in vivo effect of DP8α cells has not been evaluated yet. Here, using a humanized model of NOD.Prkcscid IL2rγ-/- (NSG) immunodeficient mouse strain that expresses the human leucocyte antigen D-related allele HLA-DR*0401 but not murine class II (NSG-Ab° DR4) molecules, we demonstrated a protective effect of a HLA-DR*0401-restricted DP8α Treg clone combined with F. prausnitzii administration in a colitis model. In a cohort of patients with IBD, we showed an independent association between the frequency of circulating DP8α cells and disease activity. Finally, we pointed out a positive correlation between F. prausnitzii-specific DP8α Tregs and the amount of F. prausnitzii in fecal microbiota in healthy individuals and patients with ileal Crohn’s disease.
Sothea Touch, Emmanuelle Godefroy, Nathalie Rolhion, Camille Danne, Cyriane Oeuvray, Marjolène Straube, Chloé Galbert, Loïc Brot, Iria Alonso Salgueiro, Sead Chadi, Tatiana Ledent, Jean-Marc Chatel, Philippe Langella, Francine Jotereau, Frédéric Altare, Harry Sokol
Recent studies highlighted the clinicopathologic importance of tumor microenvironment (TME) in delineating molecular attributes and therapeutic potentials. However, the overall TME cell-infiltration landscape in non-squamous NSCLC have not been comprehensively recognized. In this study, we employed consensus non-negative matrix factorization (NMF) molecular subtyping to determine the TME cell infiltration patterns and identified three TME clusters (TME-C1, -C2, -C3) characterized by distinct clinicopathologic features, infiltrating cells, and biological processes. Proteomics analyses revealed that cGAS-STING immune signaling mediated protein and phosphorylation level were significantly upregulated in inflamed-related TME-C2 clusters. The TMEsig-score extracted from the TME-related signature divided NSCLC patients into high- and low-score subgroups, where a high score was associated with favorable prognosis and immune infiltration. Genomic landscape revealed that patients with low TMEsig-score harbored greater somatic copy number alternations and higher mutation frequency of driver genes involving STK11, KEAP1 and SMARCA4 et al. Drug sensitivity analyses suggested that tumors with high TMEsig-score were responsible for favorable clinical response to immune check-point inhibitors (ICI) treatment. In summary, this study highlights that comprehensive recognizing of the TME cell infiltration landscape will contribute to enhance our understanding of TME immune regulation and promote effectiveness of precision biotherapy strategies.
Hao Chen, Tongchao Zhang, Yuan Zhang, Hao Wu, Zhen Fang, Yang Liu, Yang Chen, Zhe Wang, Shengtao Jia, Xingzhao Ji, Liang Shang, Fengying Du, Jin Liu, Ming Lu, Wei Chong
Studies have demonstrated the phenotypic heterogeneity of vascular endothelial cells (ECs) within a vascular bed; however, little is known about how distinct endothelial subpopulations in a particular organ respond to an inflammatory stimulus. We performed single cell RNA-sequencing of 35,973 lung ECs obtained during the baseline state as well as post-injury time points following inflammatory lung injury induced by lipopolysaccharide. Seurat clustering and gene expression pathway analysis identified two major subpopulations in the lung microvascular endothelium, a subpopulation enriched for expression of immune response genes such as major histocompatibility complex genes (immuneEC) and another defined by increased expression of vascular development genes such as Sox17 (devEC). The presence of immuneEC and devEC subpopulations was also observed in non-human primate lungs infected with SARS-CoV-2 and murine lungs infected with H1N1 influenza virus. Following the peak of inflammatory injury, we observed the emergence of a proliferative lung EC subpopulation. Overexpression of Sox17 prevented inflammatory activation in ECs. Thus, there appears to be a” division of labor” within the lung microvascular endothelium with some ECs showing propensity for inflammatory signaling and others for endothelial regeneration. These results provide underpinnings for the development of targeted therapies to limit inflammatory lung injury and promote regeneration.
Lianghui Zhang, Shang Gao, Zachary White, Yang Dai, Asrar B. Malik, Jalees Rehman
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