Plasmacytoid dendritic cells have divergent effects on HIV infection of initial target cells and induce a pro-retention phenotype
Tong, O;Duette, G;O'Neil, TR;Royle, CM;Rana, H;Johnson, B;Popovic, N;Dervish, S;Brouwer, MAE;Baharlou, H;Patrick, E;Ctercteko, G;Palmer, S;Lee, E;Hunter, E;Harman, AN;Cunningham, AL;Nasr, N;
PMID: 33872331 | DOI: 10.1371/journal.ppat.1009522
Although HIV infection inhibits interferon responses in its target cells in vitro, interferon signatures can be detected in vivo soon after sexual transmission, mainly attributed to plasmacytoid dendritic cells (pDCs). In this study, we examined the physiological contributions of pDCs to early HIV acquisition using coculture models of pDCs with myeloid DCs, macrophages and the resting central, transitional and effector memory CD4 T cell subsets. pDCs impacted infection in a cell-specific manner. In myeloid cells, HIV infection was decreased via antiviral effects, cell maturation and downregulation of CCR5 expression. In contrast, in resting memory CD4 T cells, pDCs induced a subset-specific increase in intracellular HIV p24 protein expression without any activation or increase in CCR5 expression, as measured by flow cytometry. This increase was due to reactivation rather than enhanced viral spread, as blocking HIV entry via CCR5 did not alter the increased intracellular p24 expression. Furthermore, the load and proportion of cells expressing HIV DNA were restricted in the presence of pDCs while reverse transcriptase and p24 ELISA assays showed no increase in particle associated reverse transcriptase or extracellular p24 production. In addition, pDCs also markedly induced the expression of CD69 on infected CD4 T cells and other markers of CD4 T cell tissue retention. These phenotypic changes showed marked parallels with resident memory CD4 T cells isolated from anogenital tissue using enzymatic digestion. Production of IFNα by pDCs was the main driving factor for all these results. Thus, pDCs may reduce HIV spread during initial mucosal acquisition by inhibiting replication in myeloid cells while reactivating latent virus in resting memory CD4 T cells and retaining them for immune clearance.
Introini A, Boström S, Bradley F, Gibbs A, Glaessgen A, Tjernlund A, Broliden K.
PMID: 28542587 | DOI: 10.1371/journal.ppat.1006402
The most immediate and evident effect of mucosal exposure to semen in vivo is a local release of proinflammatory mediators accompanied by an influx of leukocytes into the female genital mucosa (FGM). The implication of such response in HIV-1 transmission has never been addressed due to limitations of currently available experimental models. Using human tissue explants from the uterine cervix, we developed a system of mucosal exposure to seminal plasma (SP) that supports HIV-1 replication. Treatment of ectocervical explants with SP resulted in the upregulation of inflammatory and growth factors, including IL-6, TNF, CCL5, CCL20, CXCL1, and CXCL8, and IL1A, CSF2, IL7, PTGS2, as evaluated by measuring protein levels in explant conditioned medium (ECM) and gene expression in tissue. SP treatment was also associated with increased recruitment of monocytes and neutrophils, as observed upon incubation of peripheral blood leukocytes with ECM in a transwell system. To evaluate the impact of the SP-mediated response on local susceptibility to HIV-1, we infected ectocervical explants with the CCR5-tropic variant HIV-1BaL either in the presence of SP, or after explant pre-incubation with SP. In both experimental settings SP enhanced virus replication as evaluated by HIV-1 p24gag released in explant culture medium over time, as well as by HIV-1 DNA quantification in explants infected in the presence of SP. These results suggest that a sustained inflammatory response elicited by SP soon after coitus may promote HIV-1 transmission to the FGM. Nevertheless, ectocervical tissue explants did not support the replication of transmitted/founder HIV-1 molecular clones, regardless of SP treatment. Our system offers experimental and analytical advantages over traditional models of HIV-1 transmission for the study of SP immunoregulatory effect on the FGM, and may provide a useful platform to ultimately identify new determinants of HIV-1 infection at this site.
Cytokine RNA In Situ Hybridization Permits Individualized Molecular Phenotyping in Biopsies of Psoriasis and Atopic Dermatitis
Wang, A;Fogel, A;Murphy, M;Panse, G;McGeary, M;McNiff, J;Bosenberg, M;Vesely, M;Cohen, J;Ko, C;King, B;Damsky, W;
| DOI: 10.1016/j.xjidi.2021.100021
Detection of individual cytokines in routine biopsies from patients with inflammatory skin diseases has the potential to personalize diagnosis and treatment selection, but this approach has been limited by technical feasibility. We evaluate whether a chromogen-based RNA in situ hybridization approach can be used to detect druggable cytokines in psoriasis and atopic dermatitis. A series of psoriasis (n = 20) and atopic dermatitis (n = 26) biopsies were stained using RNA in situ hybridization for IL4, IL12B (IL-12/23 p40), IL13, IL17A, IL17F, IL22, IL23A (IL-23 p19), IL31, and TNF (TNF-α). NOS2 and IFNG, canonical psoriasis biomarkers, were also included. All 20 of the psoriasis cases were positive for IL17A, which tended to be the predominant cytokine, although some cases had relatively higher levels of IL12B, IL17F, or IL23A. The majority of cytokine expression in psoriasis was epidermal. A total of 22 of 26 atopic dermatitis cases were positive for IL13, also at varying levels; a subset of cases had significant IL4, IL22, or IL31 expression. Patterns were validated in independent bulk RNA-sequencing and single-cell RNA-sequencing datasets. Overall, RNA in situ hybridization for cytokines appears highly specific with virtually no background staining and may allow for individualized evaluation of treatment-relevant cytokine targets in biopsies from patients with inflammatory skin disorders.
Scandinavian journal of gastroenterology
James, JP;Nielsen, BS;Langholz, E;Malham, M;Høgdall, E;Riis, LB;
PMID: 37246424 | DOI: 10.1080/00365521.2023.2217313
Tumour necrosis factor-α (TNF) antagonists have improved the management of inflammatory bowel disease (IBD), however, their usage and administration persist to be suboptimal. Here, we examined the relationship between tissue-specific TNF mRNA expression in mucosal biopsies from IBD patients and anti-TNF treatment response.Archived tissue samples from patients with luminal IBD that had all been or were in treatment with anti-TNF were included (18 adults and 24 paediatric patients). Patients were stratified into three groups according to anti-TNF response: responders, primary non-responders (PNR) and secondary loss of response (SLOR). TNF mRNA was detected using RNAscope in situ hybridisation (ISH) and the expression was quantified using image analysis.The ISH analysis showed varying occurrence of TNF mRNA positive cells located in lamina propria and often with increased density in lymphoid follicles (LF). Consequently, expression estimates were obtained in whole tissue areas with and without LF. Significantly higher TNF mRNA expression levels were measured in adults compared to paediatric patients in both the analyses with and without LF (p = .015 and p = .016, respectively). Considering the relation to response, the adult and paediatric patients were evaluated separately. In adults, the TNF expression estimates were higher in PNRs compared to responders with and without LF (p = .017 and p = .024, respectively).Our data indicate that adult PNR have significantly higher TNF mRNA levels than responders. This suggests that higher anti-TNF dose may be considered for IBD patients with high TNF mRNA expression estimates from the start of treatment.
Sasaki, K;Hayamizu, Y;Murakami, R;Toi, M;Iwai, K;
PMID: 37060248 | DOI: 10.1002/1873-3468.14623
Tumor-elicited inflammation confers tumorigenic properties, including cell death resistance, proliferation, or immune evasion. To focus on inflammatory signaling in tumors, we investigated linear ubiquitination, which enhances the nuclear factor-κB signaling pathway and prevents extrinsic programmed cell death under inflammatory environments. Here, we showed that linear ubiquitination was augmented especially in tumor cells around a necrotic core. Linear ubiquitination allowed melanomas to tolerate the hostile tumor microenvironment and to extend a necrosis-containing morphology. Loss of linear ubiquitination resulted in few necrotic lesions and growth regression, further leading to repression of innate anti-PD-1 therapy resistance signatures in melanoma as well as activation of interferon responses and antigen presentation that promote immune-mediated tumor eradication. Collectively, linear ubiquitination promotes tumor-specific tissue remodeling and the ensuing immune evasion.
A RIPK1-regulated inflammatory microglial state in amyotrophic lateral sclerosis
Proceedings of the National Academy of Sciences of the United States of America
Mifflin, L;Hu, Z;Dufort, C;Hession, CC;Walker, AJ;Niu, K;Zhu, H;Liu, N;Liu, JS;Levin, JZ;Stevens, B;Yuan, J;Zou, C;
PMID: 33766915 | DOI: 10.1073/pnas.2025102118
Microglial-derived inflammation has been linked to a broad range of neurodegenerative and neuropsychiatric conditions, including amyotrophic lateral sclerosis (ALS). Using single-cell RNA sequencing, a class of Disease-Associated Microglia (DAMs) have been characterized in neurodegeneration. However, the DAM phenotype alone is insufficient to explain the functional complexity of microglia, particularly with regard to regulating inflammation that is a hallmark of many neurodegenerative diseases. Here, we identify a subclass of microglia in mouse models of ALS which we term RIPK1-Regulated Inflammatory Microglia (RRIMs). RRIMs show significant up-regulation of classical proinflammatory pathways, including increased levels of Tnf and Il1b RNA and protein. We find that RRIMs are highly regulated by TNFα signaling and that the prevalence of these microglia can be suppressed by inhibiting receptor-interacting protein kinase 1 (RIPK1) activity downstream of the TNF receptor 1. These findings help to elucidate a mechanism by which RIPK1 kinase inhibition has been shown to provide therapeutic benefit in mouse models of ALS and may provide an additional biomarker for analysis in ongoing phase 2 clinical trials of RIPK1 inhibitors in ALS.
Gumbs, SBH;Kübler, R;Gharu, L;Schipper, PJ;Borst, AL;Snijders, GJLJ;Ormel, PR;van Berlekom, AB;Wensing, AMJ;de Witte, LD;Nijhuis, M;
PMID: 35138593 | DOI: 10.1007/s13365-021-01049-w
HIV persistence in the CNS despite antiretroviral therapy may cause neurological disorders and poses a critical challenge for HIV cure. Understanding the pathobiology of HIV-infected microglia, the main viral CNS reservoir, is imperative. Here, we provide a comprehensive comparison of human microglial culture models: cultured primary microglia (pMG), microglial cell lines, monocyte-derived microglia (MDMi), stem cell-derived microglia (iPSC-MG), and microglia grown in 3D cerebral organoids (oMG) as potential model systems to advance HIV research on microglia. Functional characterization revealed phagocytic capabilities and responsiveness to LPS across all models. Microglial transcriptome profiles of uncultured pMG showed the highest similarity to cultured pMG and oMG, followed by iPSC-MG and then MDMi. Direct comparison of HIV infection showed a striking difference, with high levels of viral replication in cultured pMG and MDMi and relatively low levels in oMG resembling HIV infection observed in post-mortem biopsies, while the SV40 and HMC3 cell lines did not support HIV infection. Altogether, based on transcriptional similarities to uncultured pMG and susceptibility to HIV infection, MDMi may serve as a first screening tool, whereas oMG, cultured pMG, and iPSC-MG provide more representative microglial culture models for HIV research. The use of current human microglial cell lines (SV40, HMC3) is not recommended.
Human anogenital monocyte-derived dendritic cells and langerin+cDC2 are major HIV target cells
Rhodes, JW;Botting, RA;Bertram, KM;Vine, EE;Rana, H;Baharlou, H;Vegh, P;O'Neil, TR;Ashhurst, AS;Fletcher, J;Parnell, GP;Graham, JD;Nasr, N;Lim, JJK;Barnouti, L;Haertsch, P;Gosselink, MP;Di Re, A;Reza, F;Ctercteko, G;Jenkins, GJ;Brooks, AJ;Patrick, E;Byrne, SN;Hunter, E;Haniffa, MA;Cunningham, AL;Harman, AN;
PMID: 33846309 | DOI: 10.1038/s41467-021-22375-x
Tissue mononuclear phagocytes (MNP) are specialised in pathogen detection and antigen presentation. As such they deliver HIV to its primary target cells; CD4 T cells. Most MNP HIV transmission studies have focused on epithelial MNPs. However, as mucosal trauma and inflammation are now known to be strongly associated with HIV transmission, here we examine the role of sub-epithelial MNPs which are present in a diverse array of subsets. We show that HIV can penetrate the epithelial surface to interact with sub-epithelial resident MNPs in anogenital explants and define the full array of subsets that are present in the human anogenital and colorectal tissues that HIV may encounter during sexual transmission. In doing so we identify two subsets that preferentially take up HIV, become infected and transmit the virus to CD4 T cells; CD14+CD1c+ monocyte-derived dendritic cells and langerin-expressing conventional dendritic cells 2 (cDC2).
Investigative Ophthalmology & Visual Science
Oikawa, K;Kiland, J;Mathu, V;Torne, O;
METHODS : Retinal, optic nerve head (ONH) and distal optic nerve (ON) tissues from 8 juvenile 10-12 week-old cats (4 males and 4 females) with feline congenital glaucoma (FCG) and 5 age-matched normal control cats (3 males and 2 females) were used. Data for weekly intraocular pressure (IOP) and optic nerve axon counts were available for all subjects. Protein and gene expression in tissue cryosections were examined by immunofluorescence labeling (IF) and RNAscope in situ hybridization (ISH), respectively. Retinal tissue was IF labeled for myeloid cell marker, IBA-1 and flat-mounted. ISH for markers of infiltrating monocytes/macrophages (_CCR2_) and proinflammatory cytokines (_IL1A_, _C1QA_, _TNF_) was performed. Microglia were identified by IF of homeostatic microglial marker, P2RY12. Microscopy images wereanalyzed using Image J, QuPath and Imaris. Two-tailed unpaired t-test or Mann-Whitney test or ANOVA were used for between-group comparisons (p
