RESUMEN
Recurrent respiratory papillomatosis (RRP), a rare chronic disease caused primarily by human papillomavirus types 6 and 11, consists of repeated growth of premalignant papillomas in the airway. RRP is characterized by multiple abnormalities in innate and adaptive immunity. Natural killer (NK) cells play important roles in immune surveillance and are part of the innate immune responses that help prevent tumor growth. We identified that papillomas lack classical class I MHC and retain nonclassical class I MHC expression. Moreover, in this study, we have identified and characterized the mechanism that blocks NK cell targeting of papilloma cells. Here, we show for the first time that the PGE2 secreted by papilloma cells directly inhibits NK cells activation/degranulation principally through the PGE2 receptor EP2, and to a lesser extent through EP4 signaling. Thus, papilloma cells have a potent mechanism to block NK cell function that likely supports papilloma cell growth.
Asunto(s)
Papiloma , Infecciones por Papillomavirus , Infecciones del Sistema Respiratorio , Humanos , Dinoprostona/metabolismo , Células Asesinas NaturalesRESUMEN
Human papillomaviruses (HPVs) cause cancers of the uterine cervix, oropharynx, anus, and vulvovaginal tract. Low-risk HPVs, such as HPV6 and 11, can also cause benign mucosal lesions including genital warts, and in patients with recurrent respiratory papillomatosis, lesions in the larynx, and on occasion, in the lungs. However, both high and less tumorigenic HPVs share a striking commonality in manipulating both innate and adaptive immune responses in HPV- infected keratinocytes, the natural host for HPV infection. In addition, immune/inflammatory cell infiltration into the tumor microenvironment influences cancer growth and prognosis, and this process is tightly regulated by different chemokines. Chemokines are small proteins and exert their biological effects by binding with G protein-coupled chemokine receptors (GPCRs) that are found on the surfaces of select target cells. Chemokines are not only involved in the establishment of a pro-tumorigenic microenvironment and organ-directed metastases but also involved in disease progression through enhancing tumor cell growth and proliferation. Therefore, having a solid grasp on chemokines and immune checkpoint modulators can help in the treatment of these cancers. In this review, we discuss the recent advances on the expression patterns and regulation of the main chemokines found in HPV-induced cancers, and their effects on both immune and non-immune cells in these lesions. Importantly, we also present the current knowledge of therapeutic interventions on the expression of specific chemokine and their receptors that have been shown to influence the development and progression of HPV-induced cancers.
Asunto(s)
Neoplasias , Infecciones por Papillomavirus , Femenino , Humanos , Infecciones por Papillomavirus/complicaciones , Quimiocinas , Neoplasias/etiología , Microambiente Tumoral , CarcinogénesisRESUMEN
Oropharyngeal squamous cell cancer (OPC) accounts for 3% of all cancers and greater than 1.5% of all cancer deaths in the United States, with marked treatment-associated morbidity in survivors. More than 80% of OPC is caused by HPV16. Tumors induced by HPV have been linked to impaired immune functions, with most studies focused on the local tumor microenvironment. Fewer studies have characterized the effects of these tumors on systemic responses in OPC, especially innate responses that drive subsequent adaptive responses, potentially creating feed-back loops favorable to the tumor. Here we report that elevated plasma levels of PGE2 are expressed in half of patients with OPC secondary to overexpression of COX-2 by peripheral blood monocytes, and this expression is driven by IL-1α secreted by the tumors. Monocytes from patients are much more sensitive to the stimulation than monocytes from controls, suggesting the possibility of enhanced immune-modulating feed-back loops. Furthermore, control monocytes pre-exposed to PGE2 overexpress COX-2 in response to IL-1α, simulating responses made by monocytes from some OPC patients. Disrupting the PGE2/IL-1α feed-back loop can have potential impact on targeted medical therapies.
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Ciclooxigenasa 2 , Interleucina-1alfa , Monocitos , Neoplasias Orofaríngeas , Humanos , Ciclooxigenasa 2/metabolismo , Dinoprostona/metabolismo , Monocitos/enzimología , Neoplasias Orofaríngeas/metabolismo , Prostaglandinas E , Microambiente Tumoral , Interleucina-1alfa/metabolismoRESUMEN
IL-36γ, a pro-inflammatory member of the IL-1 cytokine superfamily, can be induced and secreted by normal human foreskin keratinocytes (HFKs) in response to pathogenic stimuli, however, the mechanisms underlying the secretion are unknown. In this study, we demonstrate that stimulation with the TLR3 agonist, poly (I:C), led to a delayed secretion of IL-36γ compared to stimulation with the TLR5 agonist, flagellin, despite equal levels of the cytokine (p = 0.006). IL-36γ was shown to be released from HFKs in its inactive, uncleaved form, based on western blotting. Moreover, recombinant IL-36γ in its activated, cleaved form induced endogenous IL-36γ 10-fold (p = 0.004) and CXCL8 five-fold (p = 0.003) over baseline levels compared to unactivated full-length recombinant IL-36γ. The ratio of LC3b-II/LC3b-I was significantly higher in poly(I:C)-treated cells compared to flagellin-treated and unstimulated controls without a change in SQSTM1/p62 after 24 hours of stimulation (p = 0.043). Under fluorescence microscopy, poly(I:C) led to a two-fold increase at eight hours and four-fold increase at 24 hours in accumulated autophagosomes post-stimulation (p = 0.032). In contrast, autophagosomes were unchanged relative to baseline in response to flagellin. Bafilomycin A1 treatment enhanced poly(I:C)-mediated IL-36γ secretion (p = 0.044) while rapamycin led to a noticeable, but non-significant, increase in flagellin-mediated IL-36γ secretion, indicating that interrupting autophagic flux can alter IL-3γ grelease from HFKs. Finally, we show that, compared to clinically normal laryngeal tissue, there were significantly higher levels of LC3b-II in HPV-infected respiratory papilloma tissue, indicating a higher number of autophagosomes; a signature of disrupted autophagic flux.
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Flagelina , Interleucina-1 , Humanos , Flagelina/farmacología , Interleucina-1/farmacología , Interleucina-1/metabolismo , Receptor Toll-Like 3/metabolismo , Receptor Toll-Like 5 , Proteína Sequestosoma-1 , Queratinocitos/metabolismo , Poli I-C/farmacología , Citocinas , Autofagia , Sirolimus/farmacologíaRESUMEN
BACKGROUND: Allergic and nonallergic adverse reactions have been reported with global coronavirus disease 2019 (COVID-19) vaccination. It was previously hypothesized that polyethylene glycol (PEG) may be responsible for anaphylactic reactions to messenger RNA (mRNA) COVID-19 vaccines. OBJECTIVE: To report the workflow established at our institution, types, and frequency of adverse reactions to mRNA COVID-19 vaccines in patients presenting for allergy evaluation. METHODS: A COVID-19 vaccine adverse reaction registry was established. We used PEG prick skin testing, followed by PEG challenges in selected cases, to ensure PEG tolerance and encourage completion of COVID-19 vaccination series. RESULTS: A total of 113 patients were included. Most vaccine reactions (86.7%) occurred in women. Anaphylaxis occurred only in women, all of which had a history of allergic disease and two-thirds had asthma. Anaphylaxis rate was 40.6 cases per million. None of the anaphylactic cases developed hypotension, required intubation, or required hospital admission. Systemic allergic symptoms, not fulfilling anaphylaxis criteria, were significantly more common in Pfizer-BioNTech than Moderna-vaccinated patients (P = .02). We observed a higher incidence of dermatologic nonurticarial reactions in men (P = .004). Among first-dose reactors, 86.7% received and tolerated the second dose. We observed a high rate of false-positive intradermal skin test results and frequent subjective symptoms with oral PEG challenge. CONCLUSION: Intradermal PEG testing has limited utility in evaluating anaphylaxis to mRNA vaccines. Most severe postvaccination allergic symptoms are not caused by hypersensitivity to PEG. Most people with reaction to the initial mRNA vaccine can be safely revaccinated. Patients with anaphylaxis to COVID-19 vaccines benefit from physician-observed vaccination.
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Anafilaxia , Vacunas contra la COVID-19/efectos adversos , COVID-19 , Vacilación a la Vacunación , Anafilaxia/etiología , COVID-19/prevención & control , Femenino , Humanos , Masculino , Polietilenglicoles/efectos adversos , Pruebas Cutáneas , Vacunas Sintéticas/efectos adversos , Vacunas de ARNm/efectos adversosRESUMEN
Whereas large-scale statistical analyses can robustly identify disease-gene relationships, they do not accurately capture genotype-phenotype correlations or disease mechanisms. We use multiple lines of independent evidence to show that different variant types in a single gene, SATB1, cause clinically overlapping but distinct neurodevelopmental disorders. Clinical evaluation of 42 individuals carrying SATB1 variants identified overt genotype-phenotype relationships, associated with different pathophysiological mechanisms, established by functional assays. Missense variants in the CUT1 and CUT2 DNA-binding domains result in stronger chromatin binding, increased transcriptional repression, and a severe phenotype. In contrast, variants predicted to result in haploinsufficiency are associated with a milder clinical presentation. A similarly mild phenotype is observed for individuals with premature protein truncating variants that escape nonsense-mediated decay, which are transcriptionally active but mislocalized in the cell. Our results suggest that in-depth mutation-specific genotype-phenotype studies are essential to capture full disease complexity and to explain phenotypic variability.
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Proteínas de Unión a la Región de Fijación a la Matriz/genética , Mutación , Trastornos del Neurodesarrollo/genética , Cromatina/metabolismo , Femenino , Estudios de Asociación Genética , Haploinsuficiencia , Humanos , Masculino , Proteínas de Unión a la Región de Fijación a la Matriz/química , Proteínas de Unión a la Región de Fijación a la Matriz/metabolismo , Modelos Moleculares , Mutación Missense , Unión Proteica , Dominios Proteicos , Transcripción GenéticaRESUMEN
PURPOSE: To evaluate the safety and tolerability of subcutaneous IgPro20 (Hizentra®, CSL Behring, King of Prussia, PA, USA) administered at high infusion parameters (> 25 mL and > 25 mL/h per injection site) in patients with primary immunodeficiency. METHODS: The Hizentra® Label Optimization (HILO) study was an open-label, parallel-arm, non-randomized study (NCT03033745) of IgPro20 using a forced upward titration design for infusion parameters. Patients experienced with pump-assisted IgPro20 infusions received weekly IgPro20 infusions at a stable dose in the Pump-Assisted Volume Cohort (N = 15; 25-50 mL per injection site) and in the Pump-Assisted Flow Rate Cohort (N = 18; 25-100 mL/h per injection site). Responder rates (percentage of patients who successfully completed ≥ 75% of planned infusions), safety outcomes, and serum immunoglobulin G (IgG) trough levels were evaluated. RESULTS: Responder rates were 86.7% (13/15, 25 mL) and 73.3% (11/15, 40 and 50 mL) in the Volume Cohort, and 77.8% (14/18, 25 and 50 mL/h), 66.7% (12/18, 75 mL/h), and 61.1% (11/18, 100 mL/h) in the Flow Rate Cohort. Infusion compliance was ≥ 90% in all patients in the Volume Cohort and in 83.3% of patients in the Flow Rate Cohort. The number of injection sites (Volume Cohort) and the infusion duration (Flow Rate Cohort) decreased with increasing infusion parameters. The rate of treatment-emergent adverse events per infusion was low (0.138 [Volume Cohort] and 0.216 [Flow Rate Cohort]). Serum IgG levels remained stable during the study. CONCLUSION: Pump-assisted IgPro20 infusions are feasible at 50 mL and 100 mL/h per injection site in treatment-experienced patients, which may result in fewer injection sites and shorter infusion times. TRIAL REGISTRATION: NCT03033745 ; registered January 27, 2017.
Asunto(s)
Inmunoglobulina G/administración & dosificación , Inmunoglobulina G/efectos adversos , Síndromes de Inmunodeficiencia/inmunología , Síndromes de Inmunodeficiencia/terapia , Enfermedades de Inmunodeficiencia Primaria/inmunología , Enfermedades de Inmunodeficiencia Primaria/terapia , Adulto , Anciano , Estudios de Cohortes , Femenino , Humanos , Inmunoglobulina G/inmunología , Inmunoglobulinas Intravenosas/efectos adversos , Bombas de Infusión/efectos adversos , Infusiones Subcutáneas/efectos adversos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
PURPOSE: Newborn screening (NBS) quantifies T cell receptor excision circles (TREC) and identifies infants with T cell lymphopenia (TCL). This study elucidates the demographics, laboratory characteristics, genetics, and clinical outcomes following live viral vaccine administration of term infants with transient or persistent idiopathic TCL. METHODS: A single-center retrospective analysis was performed from September 2010 through June 2018. Laboratory variables were compared with Mann-Whitney tests. Correlations between initial TREC levels and T cell counts were determined by Spearman tests. RESULTS: Twenty-two transient and 21 persistent TCL infants were identified. Males comprised 68% of the transient and 52% of the persistent TCL cohorts. Whites comprised 23% of the transient and 29% of the persistent cohorts. Median initial TREC levels did not differ (66 vs. 60 TRECs/µL of blood, P = 0.58). The transient cohort had higher median initial CD3+ (2135 vs. 1169 cells/µL, P < 0.001), CD4+ (1460 vs. 866 cells/µL, P < 0.001), and CD8+ (538 vs. 277 cells/µL, P < 0.001) counts. The median age of resolution for the transient cohort was 38 days. Genetic testing revealed 2 genes of interest which warrant further study and several variants of uncertain significance in immunology-related genes in the persistent cohort. 19 transient and 14 persistent subjects received the initial rotavirus and/or MMRV immunization. No adverse reactions to live viral vaccines were reported in either cohort. CONCLUSION: Transient and persistent TCL infants differ by demographic, laboratory, and clinical characteristics. Select transient and persistent TCL patients may safely receive live attenuated viral vaccines, but larger confirmatory studies are needed.
Asunto(s)
Linfopenia/epidemiología , Linfocitos T , Recuento de Linfocito CD4 , Susceptibilidad a Enfermedades , Femenino , Humanos , Recién Nacido , Recuento de Linfocitos , Linfopenia/diagnóstico , Linfopenia/etiología , Masculino , Tamizaje Neonatal , New York/epidemiología , Vigilancia en Salud Pública , Estudios Retrospectivos , Vacunación , Vacunas Virales/administración & dosificación , Vacunas Virales/inmunologíaRESUMEN
PURPOSE: To evaluate the safety and tolerability of IgPro20 manual push (also known as rapid push) infusions at flow rates of 0.5-2.0 mL/min. METHODS: Patients with primary immunodeficiency (PID) with previous experience administering IgPro20 (Hizentra®, CSL Behring, King of Prussia, PA, USA) were enrolled in the Hizentra® Label Optimization (HILO) study (NCT03033745) and assigned to Pump-assisted Volume Cohort, Pump-assisted Flow Rate Cohort, or Manual Push Flow Rate Cohort; this report describes the latter. Patients administered IgPro20 via manual push at 0.5, 1.0, and 2.0 mL/min/site for 4 weeks each. Responder rates (percentage of patients who completed a predefined minimum number of infusions), safety outcomes, and serum immunoglobulin G (IgG) trough levels were evaluated. RESULTS: Sixteen patients were treated; 2 patients (12.5%) discontinued at the 1.0-mL/min level (unrelated to treatment). Responder rates were 100%, 100%, and 87.5% at 0.5-, 1.0-, and 2.0-mL/min flow rates, respectively. Mean weekly infusion duration decreased from 103-108 to 23-28 min at the 0.5- and 2.0-mL/min flow rates, respectively. Rates of treatment-related treatment-emergent adverse events (TEAEs) per infusion were 0.023, 0.082, and 0.025 for the 0.5-, 1.0-, and 2.0-mL/min flow rates, respectively. Most TEAEs were mild local reactions and tolerability (infusions without severe local reactions/total infusions) was 100% across flow rate levels. Serum IgG levels (mean [SD]) were similar at study start (9.36 [2.53] g/L) and end (9.58 [2.12] g/L). CONCLUSIONS: Subcutaneous IgPro20 manual push infusions at flow rates up to 2.0 mL/min were well tolerated and reduced infusion time in treatment-experienced patients with PID. TRIAL REGISTRATION: NCT03033745.
Asunto(s)
Inmunoglobulina G/administración & dosificación , Enfermedades de Inmunodeficiencia Primaria/tratamiento farmacológico , Adolescente , Adulto , Anciano , Manejo de la Enfermedad , Monitoreo de Drogas , Femenino , Humanos , Inmunoglobulina G/efectos adversos , Bombas de Infusión , Infusiones Subcutáneas , Inyecciones Subcutáneas , Masculino , Persona de Mediana Edad , Cooperación del Paciente , Enfermedades de Inmunodeficiencia Primaria/diagnóstico , Enfermedades de Inmunodeficiencia Primaria/etiología , Resultado del Tratamiento , Adulto JovenRESUMEN
The micromilieu within respiratory papillomas supports persistent human papillomavirus (HPV) infection and disease recurrence in patients with recurrent respiratory papillomatosis (RRP). These patients show polarized (TH2-/Treg) adaptive immunity in papillomas and blood, enriched immature Langerhans cell (iLC) numbers, and overexpression of cyclooxygenase-2/prostaglandin E2 (PGE2) in the upper airway. Blood monocyte-derived, and tissue-derived iLCs from RRP patients and controls were now studied to more fully understand innate immune dysregulation in RRP. Patients' monocytes generated fewer iLCs than controls, due to a reduced fraction of classical monocytes that generated most but not all the iLCs. Prostaglandin E2, which was elevated in RRP plasma, reduced monocyte-iLC differentiation from controls to the levels of RRP patients, but had no effect on subsequent iLC maturation. Cytokine/chemokine responses by iLCs from papillomas, foreskin, and abdominal skin differed significantly. Freshly derived tissue iLCs expressed low CCL-1 and high CCL-20 mRNAs and were unresponsive to IL-36γ stimulation. Papilloma iLCs uniquely expressed IL-36γ at baseline and expressed CCL1 when cultured overnight outside their immunosuppressive microenvironment without additional stimulation. We conclude that monocyte/iLC innate immunity is impaired in RRP, in part due to increased PGE2 exposure in vivo. The immunosuppressive papilloma microenvironment likely alters iLC responses, and vice versa, supporting TH2-like/Treg HPV-specific adaptive immunity in RRP.
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Alphapapillomavirus/fisiología , Células de Langerhans/inmunología , Infecciones por Papillomavirus/inmunología , Infecciones del Sistema Respiratorio/inmunología , Piel/virología , Linfocitos T Reguladores/inmunología , Células Th2/inmunología , Diferenciación Celular , Células Cultivadas , Citocinas/metabolismo , Humanos , Tolerancia Inmunológica , Inmunidad Innata , Recurrencia Local de Neoplasia , Lesiones Precancerosas , Piel/patología , Microambiente TumoralRESUMEN
Juvenile-onset recurrent respiratory papillomatosis (JRRP) is a rare and debilitating childhood disease that presents with recurrent growth of papillomas in the upper airway. Two common human papillomaviruses (HPVs), HPV-6 and -11, are implicated in most cases, but it is still not understood why only a small proportion of children develop JRRP following exposure to these common viruses. We report 2 siblings with a syndromic form of JRRP associated with mild dermatologic abnormalities. Whole-exome sequencing of the patients revealed a private homozygous mutation in NLRP1, encoding Nucleotide-Binding Domain Leucine-Rich Repeat Family Pyrin Domain-Containing 1. We find the NLRP1 mutant allele to be gain of function (GOF) for inflammasome activation, as demonstrated by the induction of inflammasome complex oligomerization and IL-1ß secretion in an overexpression system. Moreover, patient-derived keratinocytes secrete elevated levels of IL-1ß at baseline. Finally, both patients displayed elevated levels of inflammasome-induced cytokines in the serum. Six NLRP1 GOF mutations have previously been described to underlie 3 allelic Mendelian diseases with differing phenotypes and modes of inheritance. Our results demonstrate that an autosomal recessive, syndromic form of JRRP can be associated with an NLRP1 GOF mutation.
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Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Reguladoras de la Apoptosis/genética , Mutación con Ganancia de Función , Homocigoto , Infecciones por Papillomavirus/genética , Infecciones por Papillomavirus/patología , Infecciones del Sistema Respiratorio/genética , Infecciones del Sistema Respiratorio/patología , Preescolar , Citocinas/metabolismo , Femenino , Humanos , Lactante , Inflamasomas , Queratinocitos/citología , Queratinocitos/inmunología , Queratinocitos/metabolismo , Masculino , Proteínas NLR , Linaje , Hermanos , SíndromeAsunto(s)
Antineoplásicos Inmunológicos/uso terapéutico , Síndromes de Inmunodeficiencia/terapia , Linfoma/terapia , Enfermedades de Inmunodeficiencia Primaria/terapia , Rituximab/uso terapéutico , Sinusitis/terapia , Humanos , Síndromes de Inmunodeficiencia/inmunología , Linfoma/inmunología , Enfermedades de Inmunodeficiencia Primaria/inmunología , Calidad de Vida , Sinusitis/inmunologíaRESUMEN
Secondary hypogammaglobulinemia is a common development in patients treated with immunomodulatory agents for autoimmune, connective tissue, and malignant diseases. It has been observed in the medical management of patients undergoing hematopoietic stem cell and solid organ transplantation. Some patients have preexisting immunodeficiency associated with these illnesses; immunosuppressive treatment magnifies their immune defect. This article reviews immunosuppressive medications, including biological treatments that cause secondary hypogammaglobulinemia. It summarizes risk factors for rituximab-induced hypogammaglobulinemia, such as preexisting low immunoglobulin G levels, CD19 levels, host factors, and additive effect of all immunomodulatory drugs used. The evaluation and management of secondary hypogammaglobulinemia are discussed.
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Agammaglobulinemia/complicaciones , Agammaglobulinemia/terapia , Factores Inmunológicos/efectos adversos , Trasplante de Órganos/efectos adversos , Agammaglobulinemia/etiología , Terapia Biológica/efectos adversos , Terapia Biológica/métodos , Manejo de la Enfermedad , Humanos , Inmunidad Humoral , Factores Inmunológicos/uso terapéutico , Inmunosupresores/efectos adversos , Neoplasias/complicaciones , Neoplasias/terapia , Factores de RiesgoRESUMEN
BACKGROUND: Stratified human keratinocytes (SHKs) are an essential part of mucosal innate immune response that modulates adaptive immunity to microbes encountered in the environment. The importance of these SHKs in mucosal integrity and development has been well characterized, however their regulatory immunologic role at different mucosal sites, has not. In this study we compared the immune gene expression of SHKs from five different anatomical sites before and after HPV16 transfection using microarray analyses. METHODS: Individual pools of human keratinocytes from foreskin, cervix, vagina, gingiva, and tonsils (HFKs, HCKs, HVKs, HGKs and HTLKs) were prepared. Organotypic (raft) cultures were established for both normal and HPV16 immortalized HFKs, HCKs, HVKs, HGKs and HTLKs lines which stably maintained episomal HPV16 DNA. Microarray analysis was carried out using the HumanHT-12 V4 gene chip (Illumina). Immune gene expression profiles were obtained by global gene chip (GeneSifter) and Ingenuity pathway analysis (IPA) for each individual site, with or without HPV16 transfection. RESULTS: We examined site specific innate immune response gene expression in SHKs from all five different anatomical sites before and after HPV16 transfection. We observed marked differences in SHK immune gene repertoires within and between mucosal tracts before HPV 16 infection. In addition, we observed additional changes in SHKs immune gene repertoire patterns when these SHKs were productively transfected with HPV16. Some immune response genes were similarly expressed by SHKs from different sites. However, there was also variable expression of non-immune response genes, such as keratin genes, by the different SHKs. CONCLUSIONS: Our results suggest that keratinocytes from different anatomical sites are likely hard wired in their innate immune responses, and that these immune responses are unique depending on the anatomical site from which the SHKs were derived. These observations may help explain why select HPV types predominate at different mucosal sites, cause persistent infection at these sites, and on occasion, lead to HPV induced malignant and benign tumor development.
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Papillomavirus Humano 16/genética , Queratinocitos/inmunología , Transcriptoma/inmunología , Cuello del Útero , Femenino , Prepucio , Encía , Humanos , Inmunidad Innata , Masculino , Análisis por Micromatrices , Tonsila Palatina , Infecciones por Papillomavirus/genética , Infecciones por Papillomavirus/inmunología , Transducción de Señal , Transfección , VaginaRESUMEN
The epithelium is part of an integrated immune system where cytokines, toll-like receptors and their ligands, and extracellular vesicles play a crucial role in initiating an innate immune response. IL-36γ is a pro-inflammatory member of the IL-1 family that is mainly expressed by epithelial cells, but regulation of its expression and release are only beginning to be understood. Previous studies reported that IL-36γ is abundant in recurrent respiratory papillomatosis, a rare but devastating disease caused by human papillomaviruses (HPV) types 6 and 11, in which papillomas recurrently grow in and block the airway. Despite the overexpression of IL-36γ, papilloma tissues show no evidence of inflammation, possibly due to suppression of its release by HPVs. We have used primary human foreskin keratinocytes as a model to study IL-36γ regulation in normal epithelial cells. Low doses of poly(I:C) mediate expression and release of IL-36γ without inducing the cell death reported by those using high doses. PKR, an enzyme required for inflammasome activation, does not contribute to controlled release of IL36γ. The keratinocytes secrete IL-36γ in two forms, soluble and in extracellular vesicles. We conclude that there are two separately regulated pathways for the controlled secretion of IL-36γ from keratinocytes, which could contribute to the modulation of both local and systemic immune responses to viruses and other pathogens.