RESUMO
Genetic variations underlying susceptibility to complex autoimmune and allergic diseases are concentrated within noncoding regulatory elements termed enhancers1. The functions of a large majority of disease-associated enhancers are unknown, in part owing to their distance from the genes they regulate, a lack of understanding of the cell types in which they operate, and our inability to recapitulate the biology of immune diseases in vitro. Here, using shared synteny to guide loss-of-function analysis of homologues of human enhancers in mice, we show that the prominent autoimmune and allergic disease risk locus at chromosome 11q13.52-7 contains a distal enhancer that is functional in CD4+ regulatory T (Treg) cells and required for Treg-mediated suppression of colitis. The enhancer recruits the transcription factors STAT5 and NF-κB to mediate signal-driven expression of Lrrc32, which encodes the protein glycoprotein A repetitions predominant (GARP). Whereas disruption of the Lrrc32 gene results in early lethality, mice lacking the enhancer are viable but lack GARP expression in Foxp3+ Treg cells, which are unable to control colitis in a cell-transfer model of the disease. In human Treg cells, the enhancer forms conformational interactions with the promoter of LRRC32 and enhancer risk variants are associated with reduced histone acetylation and GARP expression. Finally, functional fine-mapping of 11q13.5 using CRISPR-activation (CRISPRa) identifies a CRISPRa-responsive element in the vicinity of risk variant rs11236797 capable of driving GARP expression. These findings provide a mechanistic basis for association of the 11q13.5 risk locus with immune-mediated diseases and identify GARP as a potential target in their therapy.
Assuntos
Cromossomos Humanos Par 11/genética , Colite/genética , Colite/imunologia , Elementos Facilitadores Genéticos/genética , Predisposição Genética para Doença/genética , Linfócitos T Reguladores/imunologia , Acetilação , Alelos , Animais , Cromossomos de Mamíferos/genética , Feminino , Fatores de Transcrição Forkhead/metabolismo , Histonas/metabolismo , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Sintenia/genéticaRESUMO
Prophylactic human papillomavirus (HPV) vaccines are commercially available for prevention of infection with cancerogenic HPV genotypes but are not able to combat pre-existing HPV-associated disease. In this study, we designed a nanomaterial-based therapeutic HPV vaccine, comprising manganese (Mn4+)-doped silica nanoparticles (Mn4+-SNPs) and the viral neoantigen peptide GF001 derived from the HPV16 E7 oncoprotein. We show in mice that Mn4+-SNPs act as self-adjuvants by activating the inflammatory signaling pathway via generation of reactive oxygen species, resulting in immune cell recruitment to the immunization site and dendritic cell maturation. Mn4+-SNPs further serve as Ag carriers by facilitating endo/lysosomal escape via depletion of protons in acidic endocytic compartments and subsequent Ag delivery to the cytosol for cross-presentation. The Mn4+-SNPs+GF001 nanovaccine induced strong E7-specific CD8+ T cell responses, leading to remission of established murine HPV16 E7-expressing solid TC-1 tumors and E7-expressing transgenic skin grafts. This vaccine construct offers a simple and general strategy for therapeutic HPV and potentially other cancer vaccines.
Assuntos
Antígenos de Neoplasias/imunologia , Manganês/imunologia , Nanopartículas/administração & dosagem , Neoplasias/imunologia , Neoplasias/terapia , Dióxido de Silício/imunologia , Adjuvantes Imunológicos/farmacologia , Animais , Linfócitos T CD8-Positivos/imunologia , Vacinas Anticâncer/imunologia , Células Cultivadas , Feminino , Humanos , Imunização/métodos , Imunoterapia/métodos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Papillomaviridae/imunologia , Proteínas E7 de Papillomavirus/imunologia , Infecções por Papillomavirus/imunologia , Vacinas contra Papillomavirus/imunologia , Polimorfismo de Nucleotídeo Único/imunologia , Espécies Reativas de Oxigênio/imunologia , Transdução de Sinais/imunologiaRESUMO
CD4+ regulatory T (Treg) cells, dependent upon the transcription factor Foxp3, contribute to tumour immunosuppression but are also required for immune homeostasis. There is interest in developing therapies that selectively target the immunosuppressive function of Treg cells within tumours without disrupting their systemic anti-inflammatory function. High levels of expression of chemokine (C-C motif) receptor 8 (CCR8) discriminate Treg cells within tumours from those found in systemic lymphoid tissues. It has recently been proposed that disruption of CCR8 function using blocking anti-CCR8 antibodies results in reduced accumulation of Treg cells within tumours and disruption of their immunosuppressive function. Here, using Ccr8-/- mice, we show that CCR8 function is not required for Treg cell accumulation or immunosuppression in the context of syngeneic MC38 colorectal adenocarcinoma and B16 melanoma tumours. We observed high levels of CCR8 expression on tumour-infiltrating Treg cells which were abolished in Ccr8-/- mice. High levels of CCR8 marked cells with high levels of suppressive function. However, whereas systemic ablation of Treg cells resulted in strikingly diminished tumour burden, growth of subcutaneously implanted tumours was unaffected by systemic CCR8 loss. Consistently, we observed minimal impact of systemic CCR8 ablation on the frequency, phenotype and function of tumour-infiltrating Treg cells and conventional T (Tconv) function. These findings suggest that CCR8 is not required for Treg cell accumulation and immunosuppressive function within tumours and that depletion of CCR8+ Treg cells rather than blockade of CCR8 function is a more promising avenue for selective immunotherapy.
Assuntos
Adenocarcinoma/imunologia , Neoplasias Colorretais/imunologia , Linfócitos do Interstício Tumoral/imunologia , Melanoma/imunologia , Receptores CCR8/metabolismo , Neoplasias Cutâneas/imunologia , Linfócitos T Reguladores/imunologia , Animais , Fatores de Transcrição Forkhead/metabolismo , Humanos , Tolerância Imunológica , Melanoma Experimental , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores CCR8/genéticaRESUMO
Batf3 is a transcription factor that impacts the development of CD103+ tissue-resident dendritic cells (DCs). However, whether Batf3 is absolutely required for the development of CD8+ DCs remains controversial. Id2 is required for CD8+ DC development. Here we show that bone marrow chimeric mice with a deletion of Id2 in the CD11c compartment lose the ability to reject a skin graft expressing a non-self protein antigen or mount a delayed hypersensitivity response. In contrast, Batf3-/- mice remained competent for skin graft rejection and delayed hypersensitivity, and retained a CD8+ DC population with markers characteristic of the CD11b+ DC lineage, including CD11b, CD4 and CD172α, as well as the key regulator transcription factor IRF4, but lacked IRF8 expression. CD8+ DCs in Batf3-/- mice took up and cleaved protein antigen and larger particles but were unable to phagocytose dying cells, a characteristic feature to the CD8+ DC lineage. These data clarify a requirement for CD8+ lineage DCs to induce effectors of neo-antigen-driven skin graft rejection, and improve our understanding of DC subtype commitment by demonstrating that in the absence of Batf3 CD8+ DCs can change their fate and become CD11b+ DCs.
Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Antígenos CD8/metabolismo , Células Dendríticas/imunologia , Proteínas Repressoras/metabolismo , Animais , Apresentação de Antígeno/imunologia , Antígenos/metabolismo , Linhagem da Célula , Hipersensibilidade Tardia/imunologia , Hipersensibilidade Tardia/patologia , Fatores Reguladores de Interferon/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fagocitose , Fenótipo , Transplante de PeleRESUMO
Regulatory T cells (Treg) are highly enriched within many tumors and suppress immune responses to cancer. There is intense interest in reprogramming Tregs to contribute to antitumor immunity. OX40 and CD137 are expressed highly on Tregs, activated and memory T cells, and NK cells. In this study, using a novel bispecific antibody targeting mouse OX40 and CD137 (FS120m), we show that OX40/CD137 bispecific agonism induces potent antitumor immunity partially dependent upon IFNγ production by functionally reprogrammed Tregs. Treatment of tumor-bearing animals with OX40/CD137 bispecific agonists reprograms Tregs into both fragile Foxp3+ IFNγ+ Tregs with decreased suppressive function and lineage-instable Foxp3- IFNγ+ ex-Tregs. Treg fragility is partially driven by IFNγ signaling, whereas Treg instability is associated with reduced IL2 responsiveness upon treatment with OX40/CD137 bispecific agonists. Importantly, conditional deletion of Ifng in Foxp3+ Tregs and their progeny partially reverses the antitumor efficacy of OX40/CD137 bispecific agonist therapy, revealing that reprogramming of Tregs into IFNγ-producing cells contributes to the anti-tumor efficacy of OX40/CD137 bispecific agonists. These findings provide insights into mechanisms by which bispecific agonist therapies targeting costimulatory receptors highly expressed by Tregs potentiate antitumor immunity in mouse models. SIGNIFICANCE: The bispecific antibody FS120, an immunotherapy currently being tested in the clinic, partially functions by inducing anti-tumor activity of Tregs, which results in tumor rejection.
Assuntos
Anticorpos Biespecíficos , Interferon gama , Receptores OX40 , Linfócitos T Reguladores , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral , Animais , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Receptores OX40/agonistas , Receptores OX40/imunologia , Camundongos , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/agonistas , Interferon gama/metabolismo , Anticorpos Biespecíficos/farmacologia , Anticorpos Biespecíficos/uso terapêutico , Camundongos Endogâmicos C57BL , Humanos , Linhagem Celular Tumoral , FemininoRESUMO
Natural killer (NK) cells are critical to immune surveillance against infections and cancer. Their role in immune surveillance requires that NK cells are present within tissues in a quiescent state. Mechanisms by which NK cells remain quiescent in tissues are incompletely elucidated. The transcriptional repressor BACH2 plays a critical role within the adaptive immune system, but its function within innate lymphocytes has been unclear. Here, we show that BACH2 acts as an intrinsic negative regulator of NK cell maturation and function. BACH2 is expressed within developing and mature NK cells and promotes the maintenance of immature NK cells by restricting their maturation in the presence of weak stimulatory signals. Loss of BACH2 within NK cells results in accumulation of activated NK cells with unrestrained cytotoxic function within tissues, which mediate augmented immune surveillance to pulmonary cancer metastasis. These findings establish a critical function of BACH2 as a global negative regulator of innate cytotoxic function and tumor immune surveillance by NK cells.
Assuntos
Antineoplásicos , Neoplasias , Fatores de Transcrição de Zíper de Leucina Básica/genética , Humanos , Imunidade Inata , Células Matadoras NaturaisRESUMO
Whereas effector CD4+ and CD8+ T cells promote immune activation and can drive clearance of infections and cancer, CD4+ regulatory T (Treg) cells suppress their function, contributing to both immune homeostasis and cancer immunosuppression. The transcription factor BACH2 functions as a pervasive regulator of T cell differentiation, promoting development of CD4+ Treg cells and suppressing the effector functions of multiple effector T cell (Teff) lineages. Here, we report the development of a stable cell-based bioluminescence assay of the transcription factor activity of BACH2. Tetracycline-inducible BACH2 expression resulted in suppression of phorbol 12-myristate 13-acetate (PMA)/ionomycin-driven activation of a luciferase reporter containing BACH2/AP-1 target sequences from the mouse Ifng + 18k enhancer. BACH2 expression repressed the luciferase signal in a dose-dependent manner but this activity was abolished at high levels of AP-1 signalling, suggesting contextual regulation of AP-1 driven gene expression by BACH2. Finally, using the reporter assay developed, we find that the histone deacetylase 3 (HDAC3)-selective inhibitor, RGFP966, inhibits BACH2-mediated repression of signal-driven luciferase expression. In addition to enabling mechanistic studies, this cell-based reporter may enable identification of small molecule agonists or antagonists of BACH2 function for drug development.
Assuntos
Acrilamidas/farmacologia , Fatores de Transcrição de Zíper de Leucina Básica/genética , Medições Luminescentes/métodos , Fenilenodiaminas/farmacologia , Acetato de Tetradecanoilforbol/análogos & derivados , Fator de Transcrição AP-1/genética , Animais , Diferenciação Celular , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Células Jurkat , Luciferases/genética , Luciferases/metabolismo , Camundongos , Tetraciclina/farmacologia , Acetato de Tetradecanoilforbol/farmacologiaRESUMO
Regulatory T (Treg) cell populations are composed of functionally quiescent resting Treg (rTreg) cells which differentiate into activated Treg (aTreg) cells upon antigen stimulation. How rTreg cells remain quiescent despite chronic exposure to cognate self- and foreign antigens is unclear. The transcription factor BACH2 is critical for early Treg lineage specification, but its function following lineage commitment is unresolved. Here, we show that BACH2 is repurposed following Treg lineage commitment and promotes the quiescence and long-term maintenance of rTreg cells. Bach2 is highly expressed in rTreg cells but is down-regulated in aTreg cells and during inflammation. In rTreg cells, BACH2 binds to enhancers of genes involved in aTreg differentiation and represses their TCR-driven induction by competing with AP-1 factors for DNA binding. This function promotes rTreg cell quiescence and long-term maintenance and is required for immune homeostasis and durable immunosuppression in cancer. Thus, BACH2 supports a "division of labor" between quiescent rTreg cells and their activated progeny in Treg maintenance and function, respectively.
Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Ciclo Celular , Homeostase , Terapia de Imunossupressão , Neoplasias/imunologia , Neoplasias/patologia , Linfócitos T Reguladores/imunologia , Animais , Fatores de Transcrição de Zíper de Leucina Básica/deficiência , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Linhagem Celular Tumoral , Linhagem da Célula , Citocinas/metabolismo , Regulação para Baixo , Fatores de Transcrição Forkhead/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Inflamação/patologia , Integrases/metabolismo , Camundongos Endogâmicos C57BL , Neoplasias/genética , Fenótipo , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T Reguladores/citologia , Fator de Transcrição AP-1/metabolismoRESUMO
In a low inflammatory skin environment, Langerhans cells (LCs) - but not dermal dendritic cells (dDCs) - contribute to the pivotal process of tolerance induction. Thus LCs are a target for specific-tolerance therapies. LCs reside just below the stratum corneum, within the skin's viable epidermis. One way to precisely deliver immunotherapies to LCs while remaining minimally invasive is with a skin delivery device such as a microprojection arrays (MPA). Today's MPAs currently achieve rapid delivery (e.g. within minutes of application), but are focussed primarily at delivery of therapeutics to the dermis, deeper within the skin. Indeed, no MPA currently delivers specifically to the epidermal LCs of mouse skin. Without any convenient, pre-clinical device available, advancement of LC-targeted therapies has been limited. In this study, we designed and tested a novel MPA that delivers ovalbumin to the mouse epidermis (eMPA) while maintaining a low, local inflammatory response (as defined by low erythema after 24â¯h). In comparison to available dermal-targeted MPAs (dMPA), only eMPAs with larger projection tip surface areas achieved shallow epidermal penetration at a low application energy. The eMPA characterised here induced significantly less erythema after 24â¯h (pâ¯=â¯0.0004), less epidermal swelling after 72â¯h (pâ¯<â¯0.0001) and 52% less epidermal cell death than the dMPA. Despite these differences in skin inflammation, the eMPA and dMPA promoted similar levels of LC migration out of the skin. However, only the eMPA promoted LCs to migrate with a low MHC II expression and in the absence of dDC migration. Implementing this more mouse-appropriate and low-inflammatory eMPA device to deliver potential immunotherapeutics could improve the practicality and cell-specific targeting of such therapeutics in the pre-clinical stage. Leading to more opportunities for LC-targeted therapeutics such as for allergy immunotherapy and asthma.
Assuntos
Derme/química , Portadores de Fármacos/química , Epiderme/efeitos dos fármacos , Inflamação/prevenção & controle , Células de Langerhans/metabolismo , Ovalbumina/química , Animais , Movimento Celular , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Células Epidérmicas/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Modelos Teóricos , Ovalbumina/administração & dosagem , Cimento de Policarboxilato/química , Silício/química , Pele , Adesivo TransdérmicoRESUMO
"High-risk" human papillomaviruses (HPV) infect keratinocytes of squamous epithelia. The HPV16E7 protein induces epithelial hyperplasia by binding Rb family proteins and disrupting cell cycle termination. Murine skin expressing HPV16E7 as a transgene from a keratin 14 promoter (K14.E7) demonstrates epithelial hyperplasia, dysfunctional antigen presenting cells, ineffective antigen presentation by keratinocytes, and production of immunoregulatory cytokines. Furthermore, grafted K14.E7 skin is not rejected from immunocompetent non-transgenic recipient animals. To establish the contributions of E7, of E7-Rb interaction and of epithelial hyperplasia to altered local skin immunity, K14.E7 skin was compared with skin from K14.E7 mice heterozygous for a mutant Rb unable to bind E7 (K14.E7xRbΔL/ΔL mice), that have normoplastic epithelium. Previously, we demonstrated that E7-speicfic T cells do not accumulate in K14.E7xRbΔL/ΔL skin grafts. Here, we further show that K14.E7xRbΔL/ΔL skin, like K14.E7 skin, is not rejected by immunocompetent non-transgenic animals. There were fewer CD11b+ antigen presenting cells in skin draining lymph nodes from animals recipient of K14.E7xRbΔL/ΔL grafts, when compared with animals receiving K14.E7 grafts or K5mOVA grafts. Maturation of migratory DCs derived from K14.E7xRbΔL/ΔL grafts found in the draining lymph nodes is significantly lower than that of K14.E7 grafts. Surprisingly, K14.E7xRbΔL/ΔL keratinocytes, unlike K14.E7 keratinocytes, are susceptible to E7 directed CTL-mediated lysis in vitro. We conclude that E7-Rb interaction and its associated epithelial hyperplasia partially contribute to the suppressive local immune responses in area affected by HPV16E7 expression.
Assuntos
Células Apresentadoras de Antígenos/imunologia , Epiderme/patologia , Papillomavirus Humano 16/imunologia , Proteínas E7 de Papillomavirus/imunologia , Infecções por Papillomavirus/imunologia , Proteínas de Ligação a Retinoblastoma/metabolismo , Proteína do Retinoblastoma/metabolismo , Animais , Células Apresentadoras de Antígenos/metabolismo , Modelos Animais de Doenças , Epiderme/imunologia , Epiderme/transplante , Feminino , Papillomavirus Humano 16/genética , Humanos , Hiperplasia/imunologia , Hiperplasia/patologia , Queratinócitos/imunologia , Queratinócitos/metabolismo , Linfonodos/citologia , Linfonodos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas E7 de Papillomavirus/genética , Proteínas E7 de Papillomavirus/metabolismo , Infecções por Papillomavirus/patologia , Ligação Proteica/genética , Ligação Proteica/imunologia , Proteínas de Ligação a Retinoblastoma/genética , Proteínas de Ligação a Retinoblastoma/imunologia , Proteína do Retinoblastoma/genética , Proteína do Retinoblastoma/imunologiaRESUMO
Chemokines and their receptors play an important role in the recruitment, activation and differentiation of immune cells. The chemokine receptor, CXCR3, and its ligands, CXCL9, CXCL10, and CXCL11 are key immune chemoattractants during interferon-induced inflammatory responses. Inflammation of the skin resulting from infections or autoimmune disease drives expression of CXCL9/10/11 and the subsequent recruitment of effector, CXCR3+ T cells from the circulation. The relative contributions of the different CXCR3 chemokines and the three variant isoforms of CXCR3 (CXCR3A, CXCR3B, CXCR3alt) to the inflammatory process in human skin requires further investigation. In skin cancers, the CXCR3 receptor can play a dual role whereby expression on tumor cells can lead to cancer metastasis to systemic sites while receptor expression on immune cells can frequently promote anti-tumor immune responses. This review will discuss the biology of CXCR3 and its associated ligands with particular emphasis on the skin during inflammation and carcinogenesis.
RESUMO
Chemokines regulate tissue immunity by recruiting specific subsets of immune cells. Mice expressing the E7 protein of human papilloma virus 16 as a transgene from a keratin 14 promoter (K14.E7) show increased epidermal and dermal lymphocytic infiltrates, epidermal hyperplasia, and suppressed local immunity. Here, we show that CXCL9 and CXCL10 are overexpressed in non-hematopoietic cells in skin of K14.E7 mice when compared with non-transgenic animals, and recruit CXCR3+ lymphocytes to the hyperplastic skin. Overexpression of CXCL9 and CXCL10 is not observed in E7 transgenic mice with mutated Rb gene whose protein product cannot interact with E7 (K14.E7xRbΔL/ΔL) and in consequence lack hyperplastic epithelium. CXCR3+ T cells are preferentially recruited by CXCL9 and CXCL10 in supernatants of K14.E7 but not K14.E7xRbΔL/ΔL skin cultures in vitro. CXCR3 signalling promotes infiltration of a subset of effector T lymphocytes that enables donor lymphocyte deficient, E7-expressing skin graft rejection. Taken together, this suggests that recruitment of CXCR3+ T cells can be an important factor in the rejection of precancerous skin epithelium providing they can overcome local immunosuppressive mechanisms driven by skin-resident lymphocytes.
Assuntos
Quimiocina CXCL10/imunologia , Quimiocina CXCL9/imunologia , Vigilância Imunológica/imunologia , Proteínas E7 de Papillomavirus/imunologia , Linfócitos T/imunologia , Animais , Movimento Celular/imunologia , Quimiocina CXCL10/metabolismo , Quimiocina CXCL9/metabolismo , Modelos Animais de Doenças , Feminino , Rejeição de Enxerto/imunologia , Papillomavirus Humano 16/imunologia , Hiperplasia/imunologia , Queratina-14/genética , Linfócitos do Interstício Tumoral/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas E7 de Papillomavirus/genética , Infecções por Papillomavirus/imunologia , Infecções por Papillomavirus/terapia , Infecções por Papillomavirus/virologia , Regiões Promotoras Genéticas/genética , Receptores CXCR3/imunologia , Receptores CXCR3/metabolismo , Pele/citologia , Pele/imunologia , Pele/patologia , Transplante de Pele/efeitos adversos , Linfócitos T/metabolismo , Técnicas de Cultura de Tecidos , Evasão Tumoral/imunologia , Neoplasias do Colo do Útero/imunologia , Neoplasias do Colo do Útero/terapia , Neoplasias do Colo do Útero/virologia , Displasia do Colo do Útero/imunologia , Displasia do Colo do Útero/terapia , Displasia do Colo do Útero/virologiaRESUMO
Human papillomavirus (HPV) 16 E7 (E7) protein expression in skin promotes epithelial hyperproliferation and transformation to malignancy. Grafts of murine skin expressing E7 protein as a transgene in keratinocytes are not rejected from immunocompetent recipients, whereas grafts expressing ovalbumin (OVA), with or without coexpression of E7 protein, are promptly rejected, demonstrating that E7-associated non-antigen-specific local immunosuppression is not a major determinant of lack of rejection of E7 transgenic skin. To determine whether failure of rejection of E7 skin grafts is due to failure to attract E7-specific effector T cells, E7- and OVA-specific effector CD8+ T cells, activated in vitro, were transferred to animals bearing E7 transgenic skin grafts. Three days after T cell transfer, E7-specific T cells were present in significantly greater numbers than OVA-specific T cells in the grafted skin on animals bearing recently placed or healed E7 grafts, without graft rejection, and also in the ear skin of E7 transgenic animals, without obvious pathology. E7 and OVA-specific T cells were present in lesser numbers in healed E7 grafts than in recently placed grafts and in lesser numbers in recently placed E7 transgenic epidermal grafts without E7-associated hyperproliferation, derived from E7 transgenic mice with a mutated retinoblastoma gene. These data demonstrate that effector T cells are to some extent attracted to E7 transgenic skin specifically by E7 expression, but in large measure non-specifically by the epithelial proliferation associated with E7 expression, and by the local inflammation produced by grafting. Failure of E7 graft rejection was observed despite trafficking of E7-specific effector T cells to E7-expressing epithelium, a finding of consequence for immunotherapy of HPV 16 E7-associated human cancers.
RESUMO
A validated animal model would assist with research on the immunological consequences of the chronic expression of stress keratins KRT6, KRT16, and KRT17, as observed in human pre-malignant hyperproliferative epithelium. Here we examine keratin gene expression profile in skin from mice expressing the E7 oncoprotein of HPV16 (K14E7) demonstrating persistently hyperproliferative epithelium, in nontransgenic mouse skin, and in hyperproliferative actinic keratosis lesions from human skin. We demonstrate that K14E7 mouse skin overexpresses stress keratins in a similar manner to human actinic keratoses, that overexpression is a consequence of epithelial hyperproliferation induced by E7, and that overexpression further increases in response to injury. As stress keratins modify local immunity and epithelial cell function and differentiation, the K14E7 mouse model should permit study of how continued overexpression of stress keratins impacts on epithelial tumor development and on local innate and adaptive immunity.