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1.
Hum Gene Ther ; 35(13-14): 425-438, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38251650

RESUMEN

Adeno-associated virus (AAV) vectors represent a novel tool for the delivery of genetic therapeutics and enable the treatment of a wide range of diseases. Success of this new modality is challenged, however, by cases of immune-related toxicities that complicate the clinical management of patients and potentially limit the therapeutic efficacy of AAV gene therapy. While significant progress has been made to manage immune-related liver enzyme elevations following systemic AAV delivery in humans, recent clinical trials utilizing high vector doses have highlighted a new challenge to AAV gene transfer-activation of the complement system. While current in vitro models implicate AAV-specific antibodies in the initiation of the classical complement pathway, evidence from in vivo pre-clinical and clinical studies suggests that the alternative pathway also contributes to complement activation. A convergence of AAV-specific, environmental, and patient-specific factors shaping complement responses likely contributes to differential outcomes seen in clinical trials, from priming of the adaptive immune system to serious adverse events such as hepatotoxicity and thrombotic microangiopathy. Research focused on the interplay of patient-specific and AAV-related factors driving complement activation is needed to understand and identify critical components in the complement cascade to target and devise strategies to mitigate vector-related immune responses.


Asunto(s)
Activación de Complemento , Proteínas del Sistema Complemento , Dependovirus , Terapia Genética , Vectores Genéticos , Dependovirus/genética , Dependovirus/inmunología , Humanos , Vectores Genéticos/genética , Vectores Genéticos/administración & dosificación , Vectores Genéticos/efectos adversos , Terapia Genética/métodos , Terapia Genética/efectos adversos , Proteínas del Sistema Complemento/inmunología , Animales , Técnicas de Transferencia de Gen
2.
Front Immunol ; 13: 999021, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36189251

RESUMEN

AAV gene transfer is a promising treatment for many patients with life-threatening genetic diseases. However, host immune response to the vector poses a significant challenge for the durability and safety of AAV-mediated gene therapy. Here, we characterize the innate immune response to AAV in human whole blood. We identified neutrophils, monocyte-related dendritic cells, and monocytes as the most prevalent cell subsets able to internalize AAV particles, while conventional dendritic cells were the most activated in terms of the CD86 co-stimulatory molecule upregulation. Although low titers (≤1:10) of AAV neutralizing antibodies (NAb) in blood did not have profound effects on the innate immune response to AAV, higher NAb titers (≥1:100) significantly increased pro-inflammatory cytokine/chemokine secretion, vector uptake by antigen presenting cells (APCs) and complement activation. Interestingly, both full and empty viral particles were equally potent in inducing complement activation and cytokine secretion. By using a compstatin-based C3 and C3b inhibitor, APL-9, we demonstrated that complement pathway inhibition lowered CD86 levels on APCs, AAV uptake, and cytokine/chemokine secretion in response to AAV. Together these results suggest that the pre-existing humoral immunity to AAV may contribute to trigger adverse immune responses observed in AAV-based gene therapy, and that blockade of complement pathway may warrant further investigation as a potential strategy for decreasing immunogenicity of AAV-based therapeutics.


Asunto(s)
Dependovirus , Vectores Genéticos , Anticuerpos Neutralizantes , Citocinas/genética , Dependovirus/genética , Vectores Genéticos/genética , Humanos , Inmunidad Humoral
3.
Stem Cell Res ; 53: 102332, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33857832

RESUMEN

When studying patient specific induced pluripotent stem cells (iPS cells) as a disease model, the ideal control is an isogenic line that has corrected the point mutation, instead of iPS cells from siblings or other healthy subjects. However, repairing a point mutation in iPS cells even with the newly developed CRISPR-Cas9 technique remains difficult and time-consuming. Here we report a strategy that makes the Cas9 "knock-in" methodology both hassle-free and error-free. Instead of selecting a Cas9 recognition site close to the point mutation, we chose a site located in the nearest intron. We constructed a donor template with the fragment containing the corrected point mutation as one of the homologous recombination arms flanking a PGK-PuroR cassette. After selection with puromycin, positive clones were identified and further transfected with a CRE vector to remove the PGK-PuroR cassette. Using this methodology, we successfully repaired the point mutation G2019S of the LRRK2 gene in a Parkinson Disease (PD) patient iPS line and the point mutation R329H of the AARS1 gene in a Charcot-Marie-Tooth disease (CMT) patient iPS line. These isogenic iPS lines are ideal as a control in future studies.


Asunto(s)
Células Madre Pluripotentes Inducidas , Sistemas CRISPR-Cas/genética , Células Clonales , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Recombinación Homóloga , Humanos , Mutación , Mutación Puntual
4.
Cell Rep ; 17(3): 645-652, 2016 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-27732842

RESUMEN

Aberrant hexanucleotide repeat expansions in C9orf72 are the most common genetic change underlying amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). RNA transcripts containing these expansions undergo repeat-associated non-ATG translation (RAN-T) to form five dipeptide repeat proteins (DPRs). DPRs are found as aggregates throughout the CNS of C9orf72-ALS/FTD patients, and some cause degeneration when expressed in vitro in neuronal cultures and in vivo in animal models. The spread of characteristic disease-related proteins drives the progression of pathology in many neurodegenerative diseases. While DPR toxic mechanisms continue to be investigated, the potential for DPRs to spread has yet to be determined. Using different experimental cell culture platforms, including spinal motor neurons derived from induced pluripotent stem cells from C9orf72-ALS patients, we found evidence for cell-to-cell spreading of DPRs via exosome-dependent and exosome-independent pathways, which may be relevant to disease.


Asunto(s)
Esclerosis Amiotrófica Lateral/metabolismo , Proteína C9orf72/metabolismo , Dipéptidos/química , Demencia Frontotemporal/metabolismo , Secuencias Repetitivas de Aminoácido , Animales , Dipéptidos/metabolismo , Exosomas/metabolismo , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Neuronas Motoras/metabolismo , Neuroglía/metabolismo , Neuronas/metabolismo , Ratas , Médula Espinal/patología
5.
J Immunol ; 194(8): 3784-97, 2015 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-25780041

RESUMEN

How the formation and activity of CD4(+)Foxp3(+) regulatory T cells (Tregs) are shaped by TCR recognition of the diverse array of peptide:MHC complexes that can be generated from self-antigens and/or foreign Ags in vivo remains poorly understood. We show that a self-peptide with low (but not high) stimulatory potency promotes thymic Treg formation and can induce conventional CD4(+) T cells in the periphery to become Tregs that express different levels of the transcription factor Helios according to anatomical location. When Tregs generated in response to this self-peptide subsequently encountered the same peptide derived instead from influenza virus in the lung-draining lymph nodes of infected mice, they proliferated, acquired a T-bet(+)CXCR3(+) phenotype, and suppressed the antiviral effector T cell response in the lungs. However, these self-antigen-selected Tregs were unable to suppress the antiviral immune response based on recognition of the peptide as a self-antigen rather than a viral Ag. Notably, when expressed in a more immunostimulatory form, the self-peptide inhibited the formation of T-bet(+)CXCR3(+) Tregs in response to viral Ag, and Ag-expressing B cells from these mice induced Treg division without upregulation of CXCR3. These studies show that a weakly immunostimulatory self-peptide can induce thymic and peripheral Foxp3(+) Treg formation but is unable to activate self-antigen-selected Tregs to modulate an antiviral immune response. Moreover, a strongly immunostimulatory self-peptide expressed by B cells induced Tregs to proliferate without acquiring an effector phenotype that allows trafficking from the draining lymph node to the lungs and, thereby, prevented the Tregs from suppressing the antiviral immune response.


Asunto(s)
Presentación de Antígeno , Diferenciación Celular/inmunología , Subtipo H1N1 del Virus de la Influenza A/inmunología , Pulmón/inmunología , Infecciones por Orthomyxoviridae/inmunología , Linfocitos T Reguladores/inmunología , Animales , Antígenos Virales/inmunología , Autoantígenos/inmunología , Linfocitos B/inmunología , Linfocitos B/patología , Diferenciación Celular/genética , División Celular/inmunología , Pulmón/patología , Ganglios Linfáticos/inmunología , Ganglios Linfáticos/patología , Ratones , Ratones Endogámicos BALB C , Infecciones por Orthomyxoviridae/patología , Péptidos/inmunología , Receptores de Antígenos de Linfocitos T/inmunología , Proteínas de Dominio T Box/inmunología , Linfocitos T Reguladores/patología
6.
J Immunol ; 192(7): 3043-56, 2014 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-24591372

RESUMEN

Although therapies targeting distinct cellular pathways (e.g., anticytokine versus anti-B cell therapy) have been found to be an effective strategy for at least some patients with inflammatory arthritis, the mechanisms that determine which pathways promote arthritis development are poorly understood. We have used a transgenic mouse model to examine how variations in the CD4(+) T cell response to a surrogate self-peptide can affect the cellular pathways that are required for arthritis development. CD4(+) T cells that are highly reactive with the self-peptide induce inflammatory arthritis that affects male and female mice equally. Arthritis develops by a B cell-independent mechanism, although it can be suppressed by an anti-TNF treatment, which prevented the accumulation of effector CD4(+) Th17 cells in the joints of treated mice. By contrast, arthritis develops with a significant female bias in the context of a more weakly autoreactive CD4(+) T cell response, and B cells play a prominent role in disease pathogenesis. In this setting of lower CD4(+) T cell autoreactivity, B cells promote the formation of autoreactive CD4(+) effector T cells (including Th17 cells), and IL-17 is required for arthritis development. These studies show that the degree of CD4(+) T cell reactivity for a self-peptide can play a prominent role in determining whether distinct cellular pathways can be targeted to prevent the development of inflammatory arthritis.


Asunto(s)
Artritis/inmunología , Autoinmunidad/inmunología , Linfocitos T CD4-Positivos/inmunología , Transducción de Señal/inmunología , Animales , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/farmacología , Artritis/genética , Artritis/prevención & control , Autoinmunidad/genética , Linfocitos B/inmunología , Linfocitos B/metabolismo , Linfocitos T CD4-Positivos/metabolismo , Células Cultivadas , Femenino , Citometría de Flujo , Miembro Anterior/inmunología , Miembro Anterior/metabolismo , Miembro Anterior/patología , Factores de Transcripción Forkhead/inmunología , Factores de Transcripción Forkhead/metabolismo , Miembro Posterior/inmunología , Miembro Posterior/metabolismo , Miembro Posterior/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Ratones Transgénicos , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/inmunología , Receptores de Antígenos de Linfocitos T/metabolismo , Factores Sexuales , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Factor de Necrosis Tumoral alfa/inmunología , Factor de Necrosis Tumoral alfa/metabolismo
7.
Eur J Immunol ; 44(3): 785-93, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24307208

RESUMEN

Autoreactive CD4(+) CD8(-) (CD4SP) thymocytes can be subjected to deletion when they encounter self-peptide during their development, but they can also undergo selection to become CD4SPFoxp3(+) Treg cells. We have analyzed the relationship between these distinct developmental fates using mice in which signals transmitted by the TCR have been attenuated by mutation of a critical tyrosine residue of the adapter protein SLP-76. In mice containing polyclonal TCR repertoires, the mutation caused increased frequencies of CD4SPFoxp3(+) thymocytes. CD4SP thymocytes expressing TCR Vß-chains that are subjected to deletion by endogenous retroviral superantigens were also present at increased frequencies, particularly among Foxp3(+) thymocytes. In transgenic mice in which CD4SP thymocytes expressing an autoreactive TCR undergo both deletion and Treg-cell formation in response to a defined self-peptide, SLP-76 mutation abrogated deletion of autoreactive CD4SP thymocytes. Notably, Foxp3(+) Treg-cell formation still occurred, albeit with a reduced efficiency, and the mutation was also associated with decreased Nur77 expression by the autoreactive CD4SP thymocytes. These studies provide evidence that the strength of the TCR signal can play a direct role in directing the extent of both thymocyte deletion and Treg-cell differentiation, and suggest that distinct TCR signaling thresholds and/or pathways can promote CD4SP thymocyte deletion versus Treg-cell formation.


Asunto(s)
Autoantígenos/inmunología , Supresión Clonal/inmunología , Péptidos/inmunología , Receptores de Antígenos de Linfocitos T/metabolismo , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Timocitos/inmunología , Timocitos/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Presentación de Antígeno , Autoantígenos/química , Autoinmunidad , Supresión Clonal/genética , Factores de Transcripción Forkhead/metabolismo , Expresión Génica , Subunidad alfa del Receptor de Interleucina-2/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Transgénicos , Mutación , Péptidos/química , Fenotipo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Receptores de Antígenos de Linfocitos T alfa-beta/metabolismo , Transducción de Señal
8.
J Immunol ; 190(12): 6115-25, 2013 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-23667113

RESUMEN

We examined the formation, participation, and functional specialization of virus-reactive Foxp3(+) regulatory T cells (Tregs) in a mouse model of influenza virus infection. "Natural" Tregs generated intrathymically, based on interactions with a self-peptide, proliferated in response to a homologous viral Ag in the lungs and, to a lesser extent, in the lung-draining mediastinal lymph nodes (medLNs) of virus-infected mice. In contrast, conventional CD4(+) T cells with identical TCR specificity underwent little or no conversion to become "adaptive" Tregs. The virus-reactive Tregs in the medLNs and the lungs of infected mice upregulated a variety of molecules associated with Treg activation, as well as acquired expression of molecules (T-bet, Blimp-1, and IL-10) that confer functional specialization to Tregs. Notably, however, the phenotypes of the T-bet(+) Tregs obtained from these sites were distinct, because Tregs isolated from the lungs expressed significantly higher levels of T-bet, Blimp-1, and IL-10 than did Tregs from the medLNs. Adoptive transfer of Ag-reactive Tregs led to decreased proliferation of antiviral CD4(+) and CD8(+) effector T cells in the lungs of infected hosts, whereas depletion of Tregs had a reciprocal effect. These studies demonstrate that thymically generated Tregs can become activated by a pathogen-derived peptide and acquire discrete T-bet(+) Treg phenotypes while participating in and modulating an antiviral immune response.


Asunto(s)
Activación de Linfocitos/inmunología , Infecciones por Orthomyxoviridae/inmunología , Subgrupos de Linfocitos T/inmunología , Linfocitos T Reguladores/inmunología , Traslado Adoptivo , Animales , Antígenos Virales/inmunología , Diferenciación Celular/inmunología , Citometría de Flujo , Factores de Transcripción Forkhead/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Transgénicos , Orthomyxoviridae/inmunología , Fenotipo , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Subgrupos de Linfocitos T/citología , Linfocitos T Reguladores/citología
9.
J Immunol ; 190(7): 3134-41, 2013 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-23420889

RESUMEN

We have examined mechanisms underlying the formation of pathologic Th17 cells using a transgenic mouse model in which autoreactive CD4(+) T cells recognize influenza virus hemagglutinin (HA) as a ubiquitously expressed self-Ag and induce inflammatory arthritis. The lymph nodes of arthritic mice contain elevated numbers of inflammatory monocytes (iMO) with an enhanced capacity to promote CD4(+) Th17 cell differentiation, and a regional inflammatory response develops in the paw-draining lymph nodes by an IL-17-dependent mechanism. The activation of these Th17-trophic iMO precedes arthritis development and occurs in the context of an autoreactive CD4(+) Th1 cell response. Adoptive transfer of HA-specific CD4(+) T cells into nonarthritic mice expressing HA as a self-Ag similarly led to the formation of Th1 cells and of iMO that could support Th17 cell formation, and, notably, the accumulation of these iMO in the lymph nodes was blocked by IFN-γ neutralization. These studies show that autoreactive CD4(+) Th1 cells directed to a systemically distributed self-Ag can promote the development of a regional Th17 cell inflammatory response by driving the recruitment of Th17-trophic iMO to the lymph nodes.


Asunto(s)
Artritis Experimental/inmunología , Autoinmunidad , Monocitos/inmunología , Células TH1/inmunología , Células Th17/inmunología , Animales , Autoantígenos/inmunología , Enfermedades Autoinmunes/inmunología , Linfocitos T CD4-Positivos/inmunología , Citocinas/inmunología , Inflamación/inmunología , Interferón gamma/biosíntesis , Activación de Linfocitos/inmunología , Ratones , Ratones Congénicos , Ratones Noqueados
10.
J Immunol ; 188(9): 4171-80, 2012 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-22450809

RESUMEN

CD4(+)CD25(+)Foxp3(+) regulatory T cells (Tregs) are required to restrain the immune system from mounting an autoaggressive systemic inflammatory response, but why their activity can prevent (or allow) organ-specific autoimmunity remains poorly understood. We have examined how TCR specificity contributes to Treg activity using a mouse model of spontaneous autoimmune arthritis, in which CD4(+) T cells expressing a clonotypic TCR induce disease by an IL-17-dependent mechanism. Administration of polyclonal Tregs suppressed Th17 cell formation and prevented arthritis development; notably, Tregs expressing the clonotypic TCR did not. These clonotypic Tregs exerted Ag-specific suppression of effector CD4(+) T cells using the clonotypic TCR in vivo, but failed to mediate bystander suppression and did not prevent Th17 cells using nonclonotypic TCRs from accumulating in joint-draining lymph nodes of arthritic mice. These studies indicate that the availability of Tregs with diverse TCR specificities can be crucial to their activity in autoimmune arthritis.


Asunto(s)
Artritis Experimental/inmunología , Enfermedades Autoinmunes/inmunología , Receptores de Antígenos de Linfocitos T/inmunología , Linfocitos T Reguladores/inmunología , Animales , Artritis Experimental/patología , Enfermedades Autoinmunes/patología , Interleucina-17/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Especificidad de Órganos/inmunología , Linfocitos T Reguladores/patología
11.
Proc Natl Acad Sci U S A ; 108(36): 14890-5, 2011 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-21873239

RESUMEN

CD4(+)CD25(+)Foxp3(+) regulatory T (Treg) cells are generated during thymocyte development and play a crucial role in preventing the immune system from attacking the body's cells and tissues. However, how the formation of these cells is directed by T-cell receptor (TCR) recognition of self-peptide:major histocompatibility complex (MHC) ligands remains poorly understood. We show that an agonist self-peptide with which a TCR is strongly reactive can induce a combination of thymocyte deletion and CD4(+)CD25(+)Foxp3(+) Treg cell formation in vivo. A weakly cross-reactive partial agonist self-peptide could similarly induce thymocyte deletion, but failed to induce Treg cell formation. These studies indicate that CD4(+)CD25(+)Foxp3(+) Treg cell formation can require highly stringent recognition of an agonist self-peptide by developing thymocytes. They also refine the "avidity" model of thymocyte selection by demonstrating that the quality of the signal mediated by agonist self-peptides, rather than the overall intensity of TCR signaling, can be a critical factor in directing autoreactive thymocytes to undergo CD4(+)CD25(+)Foxp3(+) Treg cell formation and/or deletion during their development.


Asunto(s)
Antígenos de Histocompatibilidad/inmunología , Modelos Inmunológicos , Péptidos/inmunología , Receptores de Antígenos de Linfocitos T/inmunología , Linfocitos T Reguladores/inmunología , Timo/inmunología , Animales , Ratones , Ratones Endogámicos BALB C , Linfocitos T Reguladores/citología , Timo/citología
12.
J Allergy Clin Immunol ; 124(4): 724-30.e4, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19767084

RESUMEN

BACKGROUND: Aspirin-exacerbated respiratory disease is characterized by asthma, nasal polyps, and intolerance to aspirin with overexpression of leukotriene (LT) C(4) synthase and cysteinyl leukotriene receptors. Through an unknown mechanism, aspirin desensitization is an effective treatment. OBJECTIVE: We hypothesized that aspirin desensitization blocks IL-4-induced expression of these LT activities through inhibition of signal transducer and activator of transcription 6 (STAT6)-mediated transcription. METHODS: Nuclear extracts were derived from THP-1 and normal human monocytes resting and cocultured with aspirin before IL-4 stimulation. Quantitative PCRs were conducted. Electrophoretic mobility shift assays were performed by using oligomers for STAT6 sites within the LT receptor and synthase promoters. Western blots of nuclear extracts were probed by using anti-phospho-STAT6 antibodies. RESULTS: Upregulation of LT receptor mRNA by IL-4 was negated by aspirin and ketorolac but not by sodium salicylate. The STAT6 site in the LT receptor and synthase promoters was confirmed by using mobility shift assays by competing with unlabeled STAT6 consensus probes and supershifts with anti-STAT6 antibodies. Aspirin and ketorolac decreased the IL-4-inducible expression of nuclear STAT6 observed in mobility shift assays and Western hybridization. CONCLUSION: The LT receptor and synthase promoters have STAT6-binding sites that are engaged by IL-4-induced nuclear extracts and inhibited by aspirin. Assuming that normal monocytes behave like monocytes from patients with aspirin-exacerbated respiratory disease, inhibition of IL-4-STAT6 might explain a mechanism in aspirin desensitization daily treatment, resulting in downregulation of production and responsiveness to cysteinyl leukotrienes. This biologic activity of aspirin likely reflects COX inhibition because it was shared with ketorolac but not sodium salicylate.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Aspirina/farmacología , Asma/inmunología , Desensibilización Inmunológica , Hipersensibilidad a las Drogas/inmunología , Factor de Transcripción STAT6/metabolismo , Antiinflamatorios no Esteroideos/efectos adversos , Aspirina/efectos adversos , Línea Celular , Ciclooxigenasa 2/efectos de los fármacos , Ciclooxigenasa 2/metabolismo , Expresión Génica/efectos de los fármacos , Expresión Génica/fisiología , Glutatión Transferasa , Humanos , Interleucina-4/farmacología , Oxidorreductasas Intramoleculares/antagonistas & inhibidores , Oxidorreductasas Intramoleculares/metabolismo , Ketorolaco/farmacología , Monocitos/efectos de los fármacos , Monocitos/inmunología , Monocitos/metabolismo , Prostaglandina-E Sintasas , Receptores de Leucotrienos/efectos de los fármacos , Receptores de Leucotrienos/metabolismo , Factor de Transcripción STAT6/antagonistas & inhibidores , Factor de Transcripción STAT6/genética , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Salicilato de Sodio/farmacología , Regulación hacia Arriba/efectos de los fármacos , Regulación hacia Arriba/fisiología
13.
Diabetes ; 57(1): 199-208, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17940120

RESUMEN

OBJECTIVE: 12/15-lipoxygenase (12/15-LO), one of a family of fatty acid oxidoreductase enzymes, reacts with polyenoic fatty acids to produce proinflammatory lipids. 12/15-LO is expressed in macrophages and pancreatic beta-cells. It enhances interleukin 12 production by macrophages, and several of its products induce apoptosis of beta-cells at nanomolar concentrations in vitro. We had previously demonstrated a role for 12/15-LO in beta-cell damage in the streptozotocin model of diabetes. Since the gene encoding 12/15-LO (gene designation Alox15) lies within the Idd4 diabetes susceptibility interval in NOD mice, we hypothesized that 12/15-LO is also a key regulator of diabetes susceptibility in the NOD mouse. RESEARCH DESIGN AND METHODS: We developed NOD mice carrying an inactivated 12/15-LO locus (NOD-Alox15(null)) using a "speed congenic" protocol, and the mice were monitored for development of insulitis and diabetes. RESULTS: NOD mice deficient in 12/15-LO develop diabetes at a markedly reduced rate compared with NOD mice (2.5 vs. >60% in females by 30 weeks). Nondiabetic female NOD-Alox15(null) mice demonstrate improved glucose tolerance, as well as significantly reduced severity of insulitis and improved beta-cell mass, when compared with age-matched nondiabetic NOD females. Disease resistance is associated with decreased numbers of islet-infiltrating activated macrophages at 4 weeks of age in NOD-Alox15(null) mice, preceding the development of insulitis. Subsequently, islet-associated infiltrates are characterized by decreased numbers of CD4(+) T cells and increased Foxp3(+) cells. CONCLUSIONS: These results suggest an important role for 12/15-LO in conferring susceptibility to autoimmune diabetes in NOD mice through its effects on macrophage recruitment or activation.


Asunto(s)
Araquidonato 12-Lipooxigenasa/genética , Araquidonato 15-Lipooxigenasa/genética , Diabetes Mellitus Tipo 1/prevención & control , Animales , Araquidonato 12-Lipooxigenasa/deficiencia , Araquidonato 15-Lipooxigenasa/deficiencia , Mapeo Cromosómico , ADN/genética , ADN/aislamiento & purificación , Cartilla de ADN , Predisposición Genética a la Enfermedad , Genoma , Glucosuria/genética , Hígado/enzimología , Activación de Macrófagos/genética , Ratones , Ratones Endogámicos NOD , Eliminación de Secuencia , Cola (estructura animal)
14.
Am J Rhinol ; 22(6): 568-81, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19178793

RESUMEN

BACKGROUND: Recent literature has indicated the feasibility of microarray analysis in the characterization of chronic sinusitis. We hypothesized that previously unexplored inflammatory mechanisms would be involved in the pathophysiology of noneosinophilic chronic rhinosinusitis with nasal polyps (NE-CRSwNP) and that this technology could be used to identify the gene expression of these novel and previously known mediators. METHODS: Patients with CRSwNP failing medical therapy were prospectively enrolled and NP tissue was removed at time of surgery. NE-CRSwNP was diagnosed based on clinical parameters including absence of allergic disease and confirmed with histopathology showing lack of eosinophilic infiltration. Messenger RNA (mRNA) transcripts extracted from study and control patients were then subjected to microarray analysis using Affymatrix based chips. Validation of findings was then confirmed via quantitative reverse transcription polymerase chain reaction (qRT-PCR). RESULTS: Microarray analysis revealed activation of pathways involved in antigen presentation, cellular movement, hematopoiesis, carcinogenesis, apoptosis, and cell signaling. Previously unexplored genes of interest were identified and their differential regulation was validated via qRT-PCR. Our data showed up-regulation of innate inflammation genes (IL-6, IL-8, and monocyte chemoattractant protein 1), hypoxia-induced inflammation 1alpha, and fibrosis (tenascin) and lack of up-regulation of genes associated with allergic, eosinophilic inflammation (IL-4 and IL-13). Additionally, the genes for CXCL1 and autocrine motility factor receptor were novelly identified to be up-regulated. CONCLUSION: This study explores the utility of gene microarray technology in identifying unexplored targets of immune dysregulation in NE-CRSwNP. Furthermore, the data characterize the immunologic profile of NE-CRSwNP as it differs from other forms of CRSwNP, in particular, those known to be associated with eosinophilic inflammation.


Asunto(s)
Análisis por Micromatrices , Pólipos Nasales/complicaciones , Sinusitis/genética , Transcripción Genética , Enfermedad Crónica , Humanos , Estudios Prospectivos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Rinitis/genética
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