RESUMEN
Systemic lupus erythematosus is characterized by hyper-activation of the immune system, multi-organ inflammation, and end-organ damage. Type I interferons (IFN-I) have been strongly implicated a role in disease etiology as has the main IFN-I-producing cell subset, the plasmacytoid dendritic cell (pDC). The B6.Nba2 mouse model develops a lupus-like disease characterized by elevated IFN-I levels and pDC pathogenicity. We have previously shown that pDC ablation prior to disease development in B6.Nba2 mice effectively prevents disease; however, it remains unclear if a similar protection can be seen if pDC ablation is initiated during later disease stages. This is important as Systemic lupus erythematosus patients are rarely diagnosed until disease is well-established and thus preventative treatment is unlikely to take place. Here we show that ablation of pDCs in the B6.Nba2 mouse model must be initiated early in order to effectively block disease development and that sustained reduction in pDC numbers is necessary for sustained effects. Finally, targeting of pDCs have been hypothesized to affect immunity towards infectious agents, in particular virus and intracellular bacteria. We show here that pDC ablation in B6.Nba2 mice does not affect the anti-viral response to encephalomyocarditic virus or a model T-dependent antigen. In summary, pDC ablation does not affect general immunity, but needs to happen early and be sustained to prevent lupus-like disease development in B6.Nba2 mice.
Asunto(s)
Interferón Tipo I , Lupus Eritematoso Sistémico , Ratones , Animales , Células Dendríticas , Modelos Animales de EnfermedadRESUMEN
The use of T-cell engagers (TCEs) to treat solid tumors is challenging, and several have been limited by narrow therapeutic windows due to substantial on-target, off-tumor toxicities due to the expression of low levels of target antigens on healthy tissues. Here, we describe TNB-928B, a fully human TCE that has a bivalent binding arm for folate receptor alpha (FRα) to selectively target FRα overexpressing tumor cells while avoiding the lysis of cells with low levels of FRα expression. The bivalent design of the FRα binding arm confers tumor selectivity due to low-affinity but high-avidity binding to high FRα antigen density cells. TNB-928B induces preferential effector T-cell activation, proliferation, and selective cytotoxic activity on high FRα expressing cells while sparing low FRα expressing cells. In addition, TNB-928B induces minimal cytokine release compared to a positive control TCE containing OKT3. Moreover, TNB-928B exhibits substantial ex vivo tumor cell lysis using endogenous T-cells and robust tumor clearance in vivo, promoting T-cell infiltration and antitumor activity in mouse models of ovarian cancer. TNB-928B exhibits pharmacokinetics similar to conventional antibodies, which are projected to enable favorable administration in humans. TNB-928B is a novel TCE with enhanced safety and specificity for the treatment of ovarian cancer.
Asunto(s)
Anticuerpos Biespecíficos , Neoplasias Ováricas , Animales , Anticuerpos Biespecíficos/uso terapéutico , Carcinoma Epitelial de Ovario , Femenino , Receptor 1 de Folato/metabolismo , Receptor 1 de Folato/uso terapéutico , Humanos , Ratones , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/patología , Linfocitos TRESUMEN
Cluster of differentiation 38 (CD38) is an ecto-enzyme expressed primarily on immune cells that metabolize nicotinamide adenine dinucleotide (NAD+) to adenosine diphosphate ribose or cyclic ADP-ribose and nicotinamide. Other substrates of CD38 include nicotinamide adenine dinucleotide phosphate and nicotinamide mononucleotide, a critical NAD+ precursor in the salvage pathway. NAD+ is an important coenzyme involved in several metabolic pathways and is a required cofactor for the function of sirtuins (SIRTs) and poly (adenosine diphosphate-ribose) polymerases. Declines in NAD+ levels are associated with metabolic and inflammatory diseases, aging, and neurodegenerative disorders. To inhibit CD38 enzyme activity and boost NAD+ levels, we developed TNB-738, an anti-CD38 biparatopic antibody that pairs two non-competing heavy chain-only antibodies in a bispecific format. By simultaneously binding two distinct epitopes on CD38, TNB-738 potently inhibited its enzymatic activity, which in turn boosted intracellular NAD+ levels and SIRT activities. Due to its silenced IgG4 Fc, TNB-738 did not deplete CD38-expressing cells, in contrast to the clinically available anti-CD38 antibodies, daratumumab, and isatuximab. TNB-738 offers numerous advantages compared to other NAD-boosting therapeutics, including small molecules, and supplements, due to its long half-life, specificity, safety profile, and activity. Overall, TNB-738 represents a novel treatment with broad therapeutic potential for metabolic and inflammatory diseases associated with NAD+ deficiencies.Abbreviations: 7-AAD: 7-aminoactinomycin D; ADCC: antibody dependent cell-mediated cytotoxicity; ADCP: antibody dependent cell-mediated phagocytosis; ADPR: adenosine diphosphate ribose; APC: allophycocyanin; cADPR: cyclic ADP-ribose; cDNA: complementary DNA; BSA: bovine serum albumin; CD38: cluster of differentiation 38; CDC: complement dependent cytotoxicity; CFA: Freund's complete adjuvant; CHO: Chinese hamster ovary; CCP4: collaborative computational project, number 4; COOT: crystallographic object-oriented toolkit; DAPI: 4',6-diamidino-2-phenylindole; DNA: deoxyribonucleic acid; DSC: differential scanning calorimetry; 3D: three dimensional; εNAD+: nicotinamide 1,N6-ethenoadenine dinucleotide; ECD: extracellular domain; EGF: epidermal growth factor; FACS: fluorescence activated cell sorting; FcγR: Fc gamma receptors; FITC: fluorescein isothiocyanate; HEK: human embryonic kidney; HEPES: 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid; IgG: immunoglobulin; IFA: incomplete Freund's adjuvant; IFNγ: Interferon gamma; KB: kinetic buffer; kDa: kilodalton; KEGG: kyoto encyclopedia of genes and genomes; LDH: lactate dehydrogenase; M: molar; mM: millimolar; MFI: mean fluorescent intensity; NA: nicotinic acid; NAD: nicotinamide adenine dinucleotide; NADP: nicotinamide adenine dinucleotide phosphate; NAM: nicotinamide; NGS: next-generation sequencing; NHS/EDC: N-Hydroxysuccinimide/ ethyl (dimethylamino propyl) carbodiimide; Ni-NTA: nickel-nitrilotriacetic acid; nL: nanoliter; NK: natural killer; NMN: nicotinamide mononucleotide; OD: optical density; PARP: poly (adenosine diphosphate-ribose) polymerase; PBS: phosphate-buffered saline; PBMC: peripheral blood mononuclear cell; PDB: protein data bank; PE: phycoerythrin; PISA: protein interfaces, surfaces, and assemblies: PK: pharmacokinetics; mol: picomolar; RNA: ribonucleic acid; RLU: relative luminescence units; rpm: rotations per minute; RU: resonance unit; SEC: size exclusion chromatography; SEM: standard error of the mean; SIRT: sirtuins; SPR: surface plasmon resonance; µg: microgram; µM: micromolar; µL: microliter.
Asunto(s)
NAD , Sirtuinas , Adenosina Difosfato Ribosa/química , Adenosina Difosfato Ribosa/metabolismo , Animales , Células CHO , Cricetinae , Cricetulus , ADP-Ribosa Cíclica , Humanos , Inmunoglobulina G , Leucocitos Mononucleares/metabolismo , NAD/química , NAD/metabolismo , NADP , Niacinamida , Mononucleótido de Nicotinamida , RibosaRESUMEN
Systemic lupus erythematosus (SLE) is an autoimmune disorder disproportionally affecting women. A similar sex difference exists in the murine New Zealand Black/White hybrid model (NZBWF1) of SLE with all females, but only 30-40% of males, developing disease within the first year of life. Myeloid-derived suppressor cells (MDSCs) are prominent in NZBWF1 males and while depletion of these cells in males, but not females, promotes disease development, the mechanism of suppression remains unknown. S100a9, expressed by neutrophils and MDSCs, has previously been shown to exert immunosuppressive functions in cancer and inflammation. Here we investigated if S100a9 exerts immunosuppressive functions in NZBWF1 male and female mice. S100a9+/+, S100a9+/- and S100a9-/- NZBWF1 mice were followed for disease development for up to 8 months of age. Serum autoantibody levels, splenomegaly, lymphocyte activation, glomerulonephritis and proteinuria were measured longitudinally or at the time of harvest. In accordance with an immunosuppressive function of MDSCs in male mice, S100a9-deficient male NZBWF1 mice developed accelerated autoimmunity as indicated by increased numbers of differentiated effector B and T cells, elevated serum autoantibody levels, increased immune-complex deposition and renal inflammation, and accelerated development of proteinuria. In contrast, female mice showed either no response to S100a9-deficiency or even a slight reduction in disease symptoms. Furthermore, male, but not female, S100a9-/- NZBWF1 mice displayed an elevated type I interferon-induced gene signature, suggesting that S100a9 may dampen a pathogenic type I interferon signal in male mice. Taken together, S100a9 exerts an immunosuppressive function in male NZBWF1 mice effectively moderating lupus-like disease development via inhibition of type I interferon production, lymphocyte activation, autoantibody production and the development of renal disease.
Asunto(s)
Calgranulina B/genética , Susceptibilidad a Enfermedades , Lupus Eritematoso Sistémico/etiología , Animales , Autoanticuerpos/inmunología , Calgranulina B/metabolismo , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades/inmunología , Expresión Génica , Predisposición Genética a la Enfermedad , Glomerulonefritis/etiología , Glomerulonefritis/metabolismo , Glomerulonefritis/patología , Humanos , Inmunohistoquímica , Inmunofenotipificación , Lupus Eritematoso Sistémico/metabolismo , Lupus Eritematoso Sistémico/patología , Activación de Linfocitos , Linfocitos/inmunología , Linfocitos/metabolismo , Masculino , Ratones , Ratones Noqueados , Infiltración Neutrófila , Factores Sexuales , Bazo/inmunología , Bazo/metabolismo , Bazo/patologíaRESUMEN
BACKGROUND: Therapeutic options currently available for metastatic castration-resistant prostate cancer (mCRPC) do not extend median overall survival >6 months. Therefore, the development of novel and effective therapies for mCRPC represents an urgent medical need. T cell engagers (TCEs) have emerged as a promising approach for the treatment of mCRPC due to their targeted mechanism of action. However, challenges remain in the clinic due to the limited efficacy of TCEs observed thus far in solid tumors as well as the toxicities associated with cytokine release syndrome (CRS) due to the usage of high-affinity anti-CD3 moieties such as OKT3. METHODS: Using genetically engineered transgenic rats (UniRat and OmniFlic) that express fully human IgG antibodies together with an NGS-based antibody discovery pipeline, we developed TNB-585, an anti-CD3xPSMA TCE for the treatment of mCRPC. TNB-585 pairs a tumor-targeting anti-PSMA arm together with a unique, low-affinity anti-CD3 arm in bispecific format. We tested TNB-585 in T cell-redirected cytotoxicity assays against PSMA+ tumor cells in both two-dimensional (2D) cultures and three-dimensional (3D) spheroids as well as against patient-derived prostate tumor cells. Cytokines were measured in culture supernatants to assess the ability of TNB-585 to induce tumor killing with low cytokine release. TNB-585-mediated T cell activation, proliferation, and cytotoxic granule formation were measured to investigate the mechanism of action. Additionally, TNB-585 efficacy was evaluated in vivo against C4-2 tumor-bearing NCG mice. RESULTS: In vitro, TNB-585 induced activation and proliferation of human T cells resulting in the killing of PSMA+ prostate tumor cells in both 2D cultures and 3D spheroids with minimal cytokine release and reduced regulatory T cell activation compared with a positive control antibody that contains the same anti-PSMA arm but a higher affinity anti-CD3 arm (comparable with OKT3). In addition, TNB-585 demonstrated potent efficacy against patient-derived prostate tumors ex vivo and induced immune cell infiltration and dose-dependent tumor regression in vivo. CONCLUSIONS: Our data suggest that TNB-585, with its low-affinity anti-CD3, may be efficacious while inducing a lower incidence and severity of CRS in patients with prostate cancer compared with TCEs that incorporate high-affinity anti-CD3 domains.
Asunto(s)
Anticuerpos Biespecíficos/administración & dosificación , Antígenos de Superficie/inmunología , Complejo CD3/inmunología , Glutamato Carboxipeptidasa II/inmunología , Inmunoglobulina G/genética , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Animales , Anticuerpos Biespecíficos/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Humanos , Macaca fascicularis , Masculino , Ratones , Células PC-3 , Neoplasias de la Próstata Resistentes a la Castración/inmunología , Ratas , Ratas Transgénicas , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
The use of recombinant interleukin-2 (IL-2) as a therapeutic protein has been limited by significant toxicities despite its demonstrated ability to induce durable tumor-regression in cancer patients. The adverse events and limited efficacy of IL-2 treatment are due to the preferential binding of IL-2 to cells that express the high-affinity, trimeric receptor, IL-2Rαßγ such as endothelial cells and T-regulatory cells, respectively. Here, we describe a novel bispecific heavy-chain only antibody which binds to and activates signaling through the heterodimeric IL-2Rßγ receptor complex that is expressed on resting T-cells and NK cells. By avoiding binding to IL-2Rα, this molecule circumvents the preferential T-reg activation of native IL-2, while maintaining the robust stimulatory effects on T-cells and NK-cells in vitro. In vivo studies in both mice and cynomolgus monkeys confirm the molecule's in vivo biological activity, extended pharmacodynamics due to the Fc portion of the molecule, and enhanced safety profile. Together, these results demonstrate that the bispecific antibody is a safe and effective IL-2R agonist that harnesses the benefits of the IL-2 signaling pathway as a potential anti-cancer therapy.
Asunto(s)
Anticuerpos Biespecíficos/farmacología , Antineoplásicos Inmunológicos/farmacología , Subunidad gamma Común de Receptores de Interleucina/agonistas , Subunidad beta del Receptor de Interleucina-2/agonistas , Linfocitos/efectos de los fármacos , Animales , Células CHO , Cricetulus , Evaluación Preclínica de Medicamentos , Células HEK293 , Humanos , Subunidad gamma Común de Receptores de Interleucina/inmunología , Subunidad beta del Receptor de Interleucina-2/inmunología , Macaca fascicularis , Masculino , Ratones Endogámicos BALB CRESUMEN
The therapeutic potential of targeting CD19 in B cell malignancies has garnered attention in the past decade, resulting in the introduction of novel immunotherapy agents. Encouraging clinical data have been reported for T cell-based targeting agents, such as anti-CD19/CD3 bispecific T-cell engager blinatumomab and chimeric antigen receptor (CAR)-T therapies, for acute lymphoblastic leukemia and B cell non-Hodgkin lymphoma (B-NHL). However, clinical use of both blinatumomab and CAR-T therapies has been limited due to unfavorable pharmacokinetics (PK), significant toxicity associated with cytokine release syndrome and neurotoxicity, and manufacturing challenges. We present here a fully human CD19xCD3 bispecific antibody (TNB-486) for the treatment of B-NHL that could address the limitations of the current approved treatments. In the presence of CD19+ target cells and T cells, TNB-486 induces tumor cell lysis with minimal cytokine release, when compared to a positive control. In vivo, TNB-486 clears CD19+ tumor cells in immunocompromised mice in the presence of human peripheral blood mononuclear cells in multiple models. Additionally, the PK of TNB-486 in mice or cynomolgus monkeys is similar to conventional antibodies. This new T cell engaging bispecific antibody targeting CD19 represents a novel therapeutic that induces potent T cell-mediated tumor-cell cytotoxicity uncoupled from high levels of cytokine release, making it an attractive candidate for B-NHL therapy.
Asunto(s)
Anticuerpos Biespecíficos/farmacología , Anticuerpos Monoclonales Humanizados/farmacología , Antineoplásicos Inmunológicos/farmacología , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD8-positivos/efectos de los fármacos , Citocinas/metabolismo , Citotoxicidad Inmunológica/efectos de los fármacos , Activación de Linfocitos/efectos de los fármacos , Linfoma no Hodgkin/tratamiento farmacológico , Animales , Anticuerpos Biespecíficos/farmacocinética , Anticuerpos Monoclonales Humanizados/farmacocinética , Antígenos CD19/inmunología , Antineoplásicos Inmunológicos/farmacocinética , Complejo CD3/antagonistas & inhibidores , Complejo CD3/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Técnicas de Cocultivo , Humanos , Células K562 , Linfoma no Hodgkin/inmunología , Linfoma no Hodgkin/metabolismo , Macaca fascicularis , Ratones Endogámicos BALB C , Ratones Endogámicos NOD , Ratones SCID , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
B6.Nba2 mice spontaneously develop a lupus-like disease characterized by elevated levels of serum anti-nuclear autoantibody (ANA) immune complexes and constitutive type I interferon (IFNα) production. During disease progression, both plasmacytoid dendritic cells (pDCs) and antibody secreting plasma cells accumulate in spleens of B6.Nba2 mice. Indoleamine 2,3-dioxygenase (IDO) has been suggested to play a role in several autoimmune diseases including in the MRL/lpr model of mouse lupus-like disease; however, it remains unknown if IDO is involved in disease development and/or progression in other spontaneous models. We show here that IDO1 protein and total IDO enzymatic activity are significantly elevated in lupus-prone B6.Nba2 mice relative to B6 controls. IDO1 expression was restricted to PCs and SignR1+ macrophages in both strains, while significantly increased in B6.Nba2-derived SiglecH+ (SigH+) pDCs. Despite this unique expression pattern, neither pharmacologic inhibition of total IDO nor IDO1 gene ablation altered serum autoantibody levels, splenic immune cell activation pattern, or renal inflammation in B6.Nba2 mice. Interestingly, IDO pharmacologic inhibition, but not IDO1 deficiency, resulted in diminished complement factor C'3 fixation to kidney glomeruli, suggesting a possible therapeutic benefit of IDO inhibition in SLE patients with renal involvement.
Asunto(s)
Expresión Génica , Indolamina-Pirrol 2,3,-Dioxigenasa/genética , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Nefritis Lúpica/etiología , Nefritis Lúpica/metabolismo , Animales , Anticuerpos Antinucleares/inmunología , Autoanticuerpos/inmunología , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Activación Enzimática , Indolamina-Pirrol 2,3,-Dioxigenasa/deficiencia , Nefritis Lúpica/patología , Ratones , Ratones Noqueados , Fenotipo , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismoRESUMEN
Financial sustainability of national immunization programmes (NIPs) in the Western Pacific is a growing concern. In the face of decreasing donor support for public immunization programmes, the role of private providers is becoming growingly important in attaining and sustaining programme achievements. Two-thirds of Member States in the Region have engaged the private sector in their immunization programmes, however little is known about the range and type of engagement. A survey was conducted in 2016 to map the scope and characteristics of private provider involvement, in order to inform guidance for decision makers. 14 countries participated, with responses from NIPs, national regulatory agencies, national immunization technical advisory groups (NITAGs), and private providers (defined as any entity other than the government). Findings revealed that most countries have policies and regulations concerning private providers, but 50% of private provider respondents were unaware that such policies are available. In most countries private providers' contribution is limited to less than 10% of the total target population. Private providers in only 6 countries surveyed follow the vaccination schedule recommended by the NIP, with demand by vaccine recipients being the main cause of deviation. A majority (>70%) of private provider respondents believe that clients seeks their services not because of perception of quality, but to access new vaccines unavailable through the NIP. Private providers in all countries received vaccines from the NIP at no cost, for which they only charge clients a service fee. The majority of private providers received training from the NIP, whereas only around 25% of them received training from their own institutions. Private providers from 11 countries share EPI performance data and adverse events following immunization, however, NIPs perceive this data as suboptimal. Private providers have a limited role in decision making processes, such as NITAGs. Further effective engagement of private sector providers has the potential to improve overall efficiency of immunization service delivery.
Asunto(s)
Programas de Inmunización/métodos , Vacunación/métodos , Humanos , Inmunización/métodos , Inmunización/estadística & datos numéricos , Programas de Inmunización/estadística & datos numéricos , Sector Privado , Vacunación/estadística & datos numéricos , Vacunas/uso terapéuticoRESUMEN
We created a novel transgenic rat that expresses human antibodies comprising a diverse repertoire of heavy chains with a single common rearranged kappa light chain (IgKV3-15-JK1). This fixed light chain animal, called OmniFlic, presents a unique system for human therapeutic antibody discovery and a model to study heavy chain repertoire diversity in the context of a constant light chain. The purpose of this study was to analyze heavy chain variable gene usage, clonotype diversity, and to describe the sequence characteristics of antigen-specific monoclonal antibodies (mAbs) isolated from immunized OmniFlic animals. Using next-generation sequencing antibody repertoire analysis, we measured heavy chain variable gene usage and the diversity of clonotypes present in the lymph node germinal centers of 75 OmniFlic rats immunized with 9 different protein antigens. Furthermore, we expressed 2,560 unique heavy chain sequences sampled from a diverse set of clonotypes as fixed light chain antibody proteins and measured their binding to antigen by ELISA. Finally, we measured patterns and overall levels of somatic hypermutation in the full B-cell repertoire and in the 2,560 mAbs tested for binding. The results demonstrate that OmniFlic animals produce an abundance of antigen-specific antibodies with heavy chain clonotype diversity that is similar to what has been described with unrestricted light chain use in mammals. In addition, we show that sequence-based discovery is a highly effective and efficient way to identify a large number of diverse monoclonal antibodies to a protein target of interest.
Asunto(s)
Anticuerpos Monoclonales/inmunología , Descubrimiento de Drogas/métodos , Genes de las Cadenas Pesadas de las Inmunoglobulinas/genética , Genes de las Cadenas Ligeras de las Inmunoglobulinas/genética , Cadenas kappa de Inmunoglobulina/inmunología , Animales , Anticuerpos Monoclonales/genética , Anticuerpos Monoclonales/uso terapéutico , Antígenos/administración & dosificación , Antígenos/inmunología , Linfocitos B/inmunología , Centro Germinal/citología , Centro Germinal/inmunología , Secuenciación de Nucleótidos de Alto Rendimiento , Cadenas Pesadas de Inmunoglobulina/genética , Cadenas Pesadas de Inmunoglobulina/inmunología , Cadenas kappa de Inmunoglobulina/genética , Modelos Animales , Ratas , Ratas Sprague-Dawley , Ratas TransgénicasRESUMEN
Heavy chain-only antibodies (HCAbs) do not associate with light chains and their VH regions are functional as single domains, forming the smallest active antibody fragment. These VH regions are ideal building blocks for a variety of antibody-based biologics because they tolerate fusion to other molecules and may also be attached in series to construct multispecific antibodies without the need for protein engineering to ensure proper heavy and light chain pairing. Production of human HCAbs has been impeded by the fact that natural human VH regions require light chain association and display poor biophysical characteristics when expressed in the absence of light chains. Here, we present an innovative platform for the rapid development of diverse sets of human HCAbs that have been selected in vivo. Our unique approach combines antibody repertoire analysis with immunization of transgenic rats, called UniRats, that produce chimeric HCAbs with fully human VH domains in response to an antigen challenge. UniRats express HCAbs from large transgenic loci representing the entire productive human heavy chain V(D)J repertoire, mount robust immune responses to a wide array of antigens, exhibit diverse V gene usage and generate large panels of stable, high affinity, antigen-specific molecules.
Asunto(s)
Anticuerpos/química , Anticuerpos/inmunología , Cadenas Pesadas de Inmunoglobulina/genética , Cadenas Pesadas de Inmunoglobulina/inmunología , Ingeniería de Proteínas/métodos , Animales , Afinidad de Anticuerpos , Antígenos/inmunología , Linfocitos B/inmunología , Células CHO , Cricetulus , Cristalografía , Citometría de Flujo , Sitios Genéticos , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Inmunización , Cadenas Ligeras de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/inmunología , Estructura Secundaria de Proteína , Ratas , Ratas Transgénicas , Anticuerpos de Dominio Único/químicaRESUMEN
Patients with systemic lupus erythematosus (SLE) often have elevated levels of type I interferon (IFN, particularly IFNα), a cytokine that can drive many of the symptoms associated with this autoimmune disorder. Additionally, the presence of autoantibody-secreting plasma cells contributes to the systemic inflammation observed in SLE and IFNα supports the survival of these cells. Current therapies for SLE are limited to broad immunosuppression or B cell-targeting antibody-mediated depletion strategies, which do not eliminate autoantibody-secreting plasma cells. Recent clinical trials testing the efficacy of IFNα neutralization in SLE have delivered disappointing results, with primary endpoints not being met or with minimal improvements, while studies evaluating antibody therapy targeting the type I IFN receptor was more successful and is currently being tested in phase III clinical studies. As many studies have supported the idea that plasmacytoid dendritic cells (pDCs) are the main source of IFNα in SLE, specifically targeting pDCs in SLE represents a new therapeutic option. Murine models suggest pDC ablation effectively ameliorates or reduces lupus-like disease development in spontaneous models of lupus and pre-clinical and phase I clinical trials support the safety of such a therapy in humans. Here we review animal studies and the current status of clinical trials targeting IFNα, type I interferon receptor and pDCs in SLE.
RESUMEN
OBJECTIVE: Patients with systemic lupus erythematosus (SLE) often present with elevated levels of interferon-α (IFNα) in serum. Plasmacytoid dendritic cells (pDCs) have been suggested to be the primary source of IFNα in SLE due to their capacity to produce high levels of IFNα. During viral infection, a subset of pDCs expressing sialic acid-binding immunoglobulin-type lectin H (Siglec H) produces the majority of pDC-derived IFNα. The aim of this study was to provide evidence that Siglec H-positive pDCs are pathogenic in the IFNα-dependent B6.Nba2 mouse model of lupus. METHODS: B6.Nba2 blood dendritic cell antigen 2 (BDCA-2)-diphtheria toxin receptor (DTR)-transgenic (Tg) mice were treated intraperitoneally with DT 3 times weekly starting at 4 weeks or 12 weeks of age and analyzed at 12 weeks and 18 weeks of age, respectively. Lupus-like disease development was measured by the presence of elevated levels of autoantibodies in serum (as determined by enzyme-linked immunosorbent assay), increased expression of IFN-inducible genes (as determined by real-time reverse transcription-polymerase chain reaction), increased IgG immune complex deposition in kidney glomeruli (as determined by immunofluorescence staining), spontaneous lymphocyte activation, and differentiation of B cells into antibody-producing plasma cells (as determined by flow cytometry). RESULTS: B6.Nba2 mice in which Siglec H-positive pDCs were depleted for 6-8 weeks displayed reduced levels of IFNα-induced gene transcripts and decreased anti-chromatin autoantibody levels in serum, and significantly fewer activated splenic T cells and B cells, germinal center B cells, follicular helper T cells, and splenic plasma cells. In 18-week-old mice, IgG immune complex deposition in kidney glomeruli was similarly reduced. CONCLUSION: The development of lupus-like disease in congenic B6.Nba2 mice depends on Siglec H-positive pDCs. We suggest that depletion of Siglec H-positive pDCs represents a novel cellular target in SLE.
Asunto(s)
Autoanticuerpos/sangre , Células Dendríticas/metabolismo , Lupus Eritematoso Sistémico/inmunología , Lectinas Similares a la Inmunoglobulina de Unión a Ácido Siálico/metabolismo , Bazo/inmunología , Animales , Autoanticuerpos/inmunología , Linfocitos B/inmunología , Cromatina/inmunología , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Centro Germinal/inmunología , Interferón-alfa/metabolismo , Lupus Eritematoso Sistémico/metabolismo , Activación de Linfocitos , Ratones , Bazo/metabolismo , Linfocitos T/inmunologíaRESUMEN
The dynamic world of healthcare requires continuous review of practice to ensure that patient care aligns with current evidence and best practice. Superficial subcutaneous lidocaine injection has been an order option at London Health Sciences Centre-University Hospital (LHSC-UH) for use in post-percutaneous coronary intervention (PCI) prior to femoral artery sheath removal (FASR). The purpose of administering lidocaine is to reduce pain during FASR, subsequently enhancing the patient's experience. A critical appraisal was performed by the Continuous Quality Improvement-Cardiac Care Council (CQI-CCC) at LHSC-UH, evaluating the effectiveness of superficial subcutaneous lidocaine for use in patients undergoing FASR. This paper details the process followed to evaluate this practice and reports on the subsequent findings and recommendations. A literature review, a retrospective chart audit, a blinded online survey and peer hospital polling were compiled, and a summary of findings was shared with the cardiac interventionists, with subsequent polling. No significant evidence for pain reduction was identified when lidocaine injections were administered prior to FASR. As such, a unanimous decision was reached to remove lidocaine from the LHSC Coronary Angioplasty Clinical Pathway order form.
Asunto(s)
Anestesia Local/enfermería , Angioplastia Coronaria con Balón/instrumentación , Angioplastia Coronaria con Balón/enfermería , Remoción de Dispositivos/enfermería , Arteria Femoral , Lidocaína , Humanos , Dimensión del Dolor/enfermería , Guías de Práctica Clínica como AsuntoRESUMEN
Act1 is a negative regulator of B-cell activation factor of the TNF family (BAFF) and CD40L-induced signaling. BALB/C mice lacking Act1 develop systemic autoimmunity resembling systemic lupus erythematosus (SLE) and Sjögren's syndrome (SjS). SLE and SjS are characterized by anti-nuclear IgG autoantibody (ANA-IgG) production and inflammation of peripheral tissues. As autoantibody production can occur in a T-cell dependent or T-cell independent manner, we investigated the role of T-cell help during Act1-mediated autoimmunity. Act1-deficiency was bred onto C57Bl/6 (B6.Act1(-/-) ) mice and B6.TCRß(-/-) TCRδ(-/-) Act1(-/-) (TKO) mice were generated. While TCRß/δ-sufficient B6.Act1(-/-) mice developed splenomegaly and lymphadenopathy, hypergammaglobulinemia, elevated levels of ANA-IgG, and kidney pathology, TKO mice failed to develop any such signs of disease. Neither B6.Act1(-/-) nor TKO mice developed SjS-like disease, suggesting that epigenetic interactions on the BALB/C background are responsible for this phenotype in BALB/C.Act1(-/-) mice. Interestingly, BAFF-driven transitional B-cell abnormalities, previously reported in BALB/C.Act1(-/-) mice, were intact in B6.Act1(-/-) mice and largely independent of T cells. In conclusion, T cells are necessary for the development of SLE-like disease in B6.Act1(-/-) mice, but not BAFF-driven transitional B-cell differentiation.
Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/deficiencia , Proteínas Adaptadoras Transductoras de Señales/inmunología , Autoinmunidad/inmunología , Factor Activador de Células B/inmunología , Inmunoglobulina M/inmunología , Lupus Eritematoso Sistémico/inmunología , Linfocitos T/inmunología , Proteínas Adaptadoras Transductoras de Señales/genética , Animales , Especificidad de Anticuerpos , Autoanticuerpos/sangre , Autoanticuerpos/inmunología , Autoinmunidad/genética , Factor Activador de Células B/sangre , Factor Activador de Células B/genética , Femenino , Citometría de Flujo , Inmunohistoquímica , Lupus Eritematoso Sistémico/genética , Enfermedades Linfáticas/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , Transducción de Señal , Esplenomegalia/inmunología , Estadísticas no Paramétricas , Linfocitos T/citologíaRESUMEN
Tanner stage indices have been frequently used in research studies to characterize the level of sexual maturation among adolescents. The Cooperative Study of Sickle Cell Disease (CSSCD) is a large multi-center study in which the assessment of Tanner stage indices has been performed to describe delays in sexual maturation and correlates of delays. Rigorous training, however, in rating Tanner stages was not provided for the clinicians in the study. Data from the CSSCD were analyzed to characterize the reliability of the assessment of sexual maturation in this study, and demonstrate the potential for increasing the reliability by more careful training. In lieu of a gold standard, a maximum likelihood algorithm was employed to examine the longitudinal consistency of Tanner stage assessments. Based on the assumption that the underlying process of sexual maturation is progressive, models were developed that allowed one to estimate jointly the incidence distribution for the attainment of Tanner stages and the error rates of assessment. Estimated false-positive rates for assessing the attainment of Tanner stages from the CSSCD ranged from 2% to 19%. Estimated false-negative rates ranged from 1% to 18%. The occurrence of these errors was found not to vary markedly with the subject's age. Error rates of this magnitude can introduce considerable bias to the estimation of the distribution of Tanner stages and result in serious losses in relative efficiency. While the validity of Tanner stage indices can be demonstrated from study data, the loss in statistical efficiency and power associated with the study error rates was severe. This underscores the utility of careful training in pubertal rating for research studies.