RESUMO
Importance: Lipoprotein(a) is a causal risk factor for atherosclerotic cardiovascular disease (ASCVD) and calcific aortic stenosis, with no pharmacological treatments approved by regulatory authorities. Objectives: To assess the safety and tolerability of zerlasiran, a short interfering RNA targeting hepatic synthesis of apolipoprotein(a), and effects on serum concentrations of lipoprotein(a). Design, Setting, and Participants: Single- and multiple-dose study in healthy participants and patients with stable ASCVD, respectively, with lipoprotein(a) serum concentrations greater than 150 nmol/L, conducted at 7 research sites in the US, the Netherlands, UK, and Australia between November 18, 2020, and February 8, 2023, with last follow-up on August 23, 2023. Interventions: Participants were randomized to receive (1) a single subcutaneous dose of placebo (n = 8), zerlasiran 300 mg (n = 6) or 600 mg (n = 6); or (2) 2 doses of placebo (n = 9), zerlasiran 200 mg (n = 9) at a 4-week interval or 300 mg (n = 9) or 450 mg (n = 9) at an 8-week interval. Main Outcomes Measures: The primary outcome was safety and tolerability. Secondary outcomes included serum levels of zerlasiran and effects on lipoprotein(a) serum concentrations. Results: Among 37 patients in the multiple-dose group (mean age, 56 [SD, 10.4] years; 15 [42%] women), 36 completed the trial. Among 14 participants with extended follow-up after single doses, 13 completed the trial. There were no serious adverse events. Median baseline lipoprotein(a) concentrations in the multiple-dose group were 288 (IQR, 199-352) nmol/L. Median changes in lipoprotein(a) concentration at 365 days after single doses were 14% (IQR, 13% to 15%) for the placebo group, -30% (IQR, -51% to -18%) for the 300 mg of zerlasiran group, and -29% (IQR, -39% to -7%) for the 600-mg dose group. After 2 doses, maximal median changes in lipoprotein(a) concentration were 19 (IQR, -17 to 28) nmol/L for the placebo group, -258 (IQR, -289 to -188) nmol/L for the 200 mg of zerlasiran group, -310 (IQR, -368 to -274) nmol/L for the 300-mg dose group, and -242 (IQR, -343 to -182) nmol/L for the 450-mg dose group, with maximal median percent change of 7% (IQR, -4% to 21%), -97% (IQR, -98% to -95%), -98% (IQR, -99% to -97%), and -99% (IQR, -99% to -98%), respectively, attenuating to 0.3% (IQR, -2% to 21%), -60% (IQR, -71% to -40%), -90% (IQR, -91% to -74%), and -89% (IQR, -91% to -76%) 201 days after administration. Conclusions: Zerlasiran was well tolerated and reduced lipoprotein(a) concentrations with infrequent administration. Trial Registration: ClinicalTrials.gov Identifier: NCT04606602.
Assuntos
Aterosclerose , Lipoproteína(a) , RNA Interferente Pequeno , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Aterosclerose/sangue , Aterosclerose/tratamento farmacológico , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Seguimentos , Injeções Subcutâneas , Internacionalidade , Lipoproteína(a)/antagonistas & inibidores , Lipoproteína(a)/sangue , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/efeitos adversos , RNA Interferente Pequeno/uso terapêutico , Resultado do TratamentoRESUMO
There is ample evidence for the role of the immune system in developing chronic pain following peripheral nerve injury. Especially Toll-like receptors (TLRs) and their associated signaling components and pro-inflammatory cytokines such as IL-1ß, induced after injury, are involved in nociceptive processes and believed to contribute to the manifestation of chronic neuropathic pain states. Whereas the inhibition of the kinase function of IRAK-4, a central kinase downstream of TLRs and IL-1 receptors (IL-1Rs), seems efficacious in various chronic inflammatory and autoimmune models, it's role in regulating chronic neuropathic pain remained elusive to date. Here, we examined whether pharmacological inhibition of IRAK-4 kinase activity using PF-06650833 and BMS-986147, two clinical-stage kinase inhibitors, is effective for controlling persistent pain following nerve injury. Both inhibitors potently inhibited TLR-triggered cytokine release in human peripheral blood mononuclear cell (PBMC) as well as human and rat whole blood cultures. BMS-986147 showing favorable pharmacokinetic (PK) properties, significantly inhibited R848-triggered plasma TNF levels in a rat in vivo cytokine release model after single oral dosing. However, BMS-986147 dose dependently reversed cold allodynia in a rat chronic constriction injury (CCI) model following intrathecal administration only, supporting the notion that central neuro-immune modulation is beneficial for treating chronic neuropathic pain. Although both inhibitors were efficacious in inhibiting IL-1ß- or TLR-triggered cytokine release in rat dorsal root ganglion cultures, only partial efficacy was reached in IL-1ß-stimulated human glial cultures indicating that inhibiting IRAK-4Ì's kinase function might be partially dispensable for human IL-1ß driven neuroinflammation. Overall, our data demonstrate that IRAK-4 inhibitors could provide therapeutic benefit in chronic pain following nerve injury, and the central driver for efficacy in the neuropathic pain model as well as potential side effects of centrally available IRAK-4 inhibitors warrant further investigation to develop effective analgesia for patients in high unmet medical need.
Assuntos
Hiperalgesia/tratamento farmacológico , Neuralgia , Inibidores de Proteínas Quinases/uso terapêutico , Animais , Quinases Associadas a Receptores de Interleucina-1 , Leucócitos Mononucleares , Neuralgia/tratamento farmacológico , Ratos , Ratos Sprague-DawleyRESUMO
Cochabambia Marcuzzi (1985) (Coleoptera: Tenebrionidae) is a junior homonym of Cochabambia Pirán, 1959 (Hemiptera: Heteroptera: Acanthosomatidae). Allotriocochabambia is proposed as a new name for the tenebrionid genus, and as result Allotriocochabambia kulzeri (1985) is proposed as new combination. The placement of Cochabambia Pirán within the Acanthosomatidae is discussed.
Assuntos
Besouros/classificação , Heterópteros/classificação , Animais , Classificação , Especificidade da EspécieRESUMO
Euschistus Dallas is distributed throughout the Western Hemisphere and is composed of 67 species in three subgenera: Euschistomorphus Jensen-Haarup, Lycipta Stl, and the nominate subgenus. Euschistus (Euschistus) includes several economically important species. Due to the lack of a phylogenetic analysis for the subgenus Euschistus, its groupings are based primarily on male genitalia. In this paper, the following Nearctic taxa that were first grouped together by Stl (1872), namely E. ictericus (Linnaeus), E. variolarius (Palisot de Beauvois), E. servus servus (Say), E. servus euschistoides (Vollenhoven), and E. tristigmus tristigmus (Say), are reviewed and redescribed. Several other similar, and probably related, taxa are also included in this study: E. tristigmus luridus (Dallas), E. inflatus Van Duzee, and E. latimarginatus Zimmer. Morphological patterns pertaining to the internal and external male and female genitalia allowed us to formalize the ictericus group to include the above-mentioned species (except E. tristigmus). The morphological overlap between the subspecies and sympatric areas of distribution have led us to consider E. servus euschistoides as a junior synonym of E. servus servus, and to corroborate the synonymy first proposed by Uhler (1861) of E. tristigmus luridus under E. tristigmus tristigmus.
Assuntos
Heterópteros , Animais , Feminino , Genitália Feminina , Masculino , FilogeniaRESUMO
Lipid- and lipoprotein-modifying therapies have expanded substantially in the last 25 years, resulting in reduction in the incidence of major adverse cardiovascular events. However, no specific lipoprotein(a) [Lp(a)]-targeting therapy has yet been shown to reduce cardiovascular disease risk. Many epidemiological and genetic studies have demonstrated that Lp(a) is an important genetically determined causal risk factor for coronary heart disease, aortic valve disease, stroke, heart failure, and peripheral vascular disease. Accordingly, the need for specific Lp(a)-lowering therapy has become a major public health priority. Approximately 20% of the global population (1.4 billion people) have elevated levels of Lp(a) associated with higher cardiovascular risk, though the threshold for determining 'high risk' is debated. Traditional lifestyle approaches to cardiovascular risk reduction are ineffective at lowering Lp(a). To address a lifelong risk factor unmodifiable by non-pharmacological means, Lp(a)-lowering therapy needs to be safe, highly effective, and tolerable for a patient population who will likely require several decades of treatment. N-acetylgalactosamine-conjugated gene silencing therapeutics, such as small interfering RNA (siRNA) and antisense oligonucleotide targeting LPA, are ideally suited for this application, offering a highly tissue- and target transcript-specific approach with the potential for safe and durable Lp(a) lowering with as few as three or four doses per year. In this review, we evaluate the causal role of Lp(a) across the cardiovascular disease spectrum, examine the role of established lipid-modifying therapies in lowering Lp(a), and focus on the anticipated role for siRNA therapeutics in treating and preventing Lp(a)-related disease.
Assuntos
Doenças Cardiovasculares , Lipoproteína(a) , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/prevenção & controle , Humanos , Lipoproteína(a)/genética , Lipoproteína(a)/metabolismo , Interferência de RNA , RNA Interferente Pequeno/efeitos adversos , RNA Interferente Pequeno/genética , Fatores de RiscoRESUMO
BACKGROUND AND AIMS: The LPA gene encodes apolipoprotein (a), a key component of Lp(a), a potent risk factor for cardiovascular disease with no specific pharmacotherapy. Here we describe the pharmacological data for SLN360, a GalNAc-conjugated siRNA targeting LPA, designed to address this unmet medical need. METHODS: SLN360 was tested in vitro for LPA knockdown in primary hepatocytes. Healthy cynomolgus monkeys received single or multiple subcutaneous doses of the SLN360 sequence ranging from 0.1 to 9.0 mg/kg to determine the pharmacokinetic and pharmacodynamic effects. Liver mRNA and serum biomarker analyses were performed. RESULTS: In vitro, the SLN360 sequence potently reduces LPA mRNA in primary cynomolgus and human hepatocytes, while no effect was observed on the expression of APOB or PLG. In vivo, SLN360 exposure peaks 2 h after subcutaneous injection with near full elimination by 24 h. Specific LPA mRNA reduction (up to 91% 2 weeks after dosing) was observed with only the 3 mg/kg group showing appreciable return to baseline (40%). No consistent dose- or time-dependent effect on the expression of APOB, PLG or a panel of sensitive markers of liver lipid accumulation was observed. Potent (up to 95%) and long lasting (≥9 weeks) serum Lp(a) reduction was observed, peaking in all active groups at day 21. The minimally effective dose was determined to be 0.3 mg/kg with an ED50 of 0.6 mg/kg. CONCLUSIONS: SLN360 induces a sustained reduction in serum Lp(a) levels in cynomolgus monkeys following subcutaneous dosing. SLN360 has potential to address the unmet need of Lp(a) reduction in cardiovascular diseases.
Assuntos
Doenças Cardiovasculares , Hiperlipidemias , Apolipoproteínas A , Apolipoproteínas B , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/genética , Humanos , Lipoproteína(a) , RNA Mensageiro , RNA Interferente Pequeno/genéticaRESUMO
In depth studies of the use of electron transfer reactions as a means to control the self-assembly of diblock copolymers with an electroactive metalloblock are reported. Specifically, the redox-triggered self-assembly of a series of polystyrene-block-polyferrocenylsilane (PS-b-PFS) diblock copolymers in dichloromethane solution is described. In the case of the amorphous polystyrene(n)-b-poly(ferrocenylphenylmethylsilane)(m) diblock copolymers (PS(n)-b-PFMPS(m): n = 548, m = 73; n = 71, m = 165; where n and m are the number-averaged degrees of polymerization), spherical micelles with an oxidized PFS core and a PS corona were formed upon oxidation of more than 50% of the ferrocenyl units by [N(C(6)H(4)Br-4)(3)][SbX(6)] (X = Cl, F). Analogous block copolymers containing a poly(ferrocenylethylmethylsilane) (PFEMS) metalloblock, which has a lower glass transition temperature, behaved similarly. However, in contrast, on replacement of the amorphous metallopolymer blocks by semicrystalline poly(ferrocenyldimethylsilane) (PFDMS) segments, a change in the observed morphology was detected with the formation of ribbon-like micelles upon oxidation of PS(535)-b-PFDMS(103) above the same threshold value. Again the coronas consisted of fully solvated PS and the core consisted of partially to fully oxidized PFS associated with the counteranions. When oxidation was performed with [N(C(6)H(4)Br-4)(3)][SbF(6)], reduction of the cores of the spherical or ribbon-like micelles with [Co(η-C(5)Me(5))(2)] enabled full recovery of the neutral chains and no significant chain scission was detected.
RESUMO
PURPOSE: In order to address cell dose limitations associated with the use of cord blood hematopoietic stem cell (HSC) transplantation, we explored the effect of bone marrow stroma-derived heparan sulfate (HS) on the ex vivo expansion of HSCs. METHODS: Heparan sulfate was isolated and purified from the conditioned media of human bone marrow stromal cells and used for the expansion of cord blood-derived CD34(+) cells in the presence of a cocktail of cytokines. RESULTS: The number of myeloid lineage-committed progenitor cells was increased at low dosage of HS as illustrated by an increase in the total number of colony-forming cells (CFC) and colonies of erythroid (BFU-E) and granulocyte-macrophage (CFU-GM) precursors. Notably, the stroma-derived HS did not alter the growth of CD34(+) HSCs or negatively affect the levels of various HSC phenotypic markers after expansion. CONCLUSIONS: This study shows that HS secreted into solution by stromal cells has the capacity to support hematopoietic cytokines in the maintenance and expansion of HSCs. The incorporation of stroma-derived HS as a reagent may improve the efficacy of cord blood HSC transplantation by enhancing the number of committed cells and accelerating the rate of engraftment.
Assuntos
Sangue Fetal/citologia , Sangue Fetal/efeitos dos fármacos , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Heparitina Sulfato/farmacologia , Células da Medula Óssea/química , Contagem de Células , Técnicas de Cultura de Células/métodos , Células Cultivadas , Transplante de Células-Tronco de Sangue do Cordão Umbilical/métodos , Meios de Cultivo Condicionados , Glicosaminoglicanos/química , Glicosaminoglicanos/isolamento & purificação , Glicosaminoglicanos/farmacologia , Células Progenitoras de Granulócitos e Macrófagos/citologia , Células Progenitoras de Granulócitos e Macrófagos/efeitos dos fármacos , Heparitina Sulfato/química , Heparitina Sulfato/isolamento & purificação , Humanos , Células Progenitoras de Megacariócitos e Eritrócitos/citologia , Células Progenitoras de Megacariócitos e Eritrócitos/efeitos dos fármacos , Células-Tronco , Células Estromais/químicaRESUMO
Using high surface area nanostructured electrodes in organic photovoltaic (OPV) devices is a route to enhanced power conversion efficiency. In this paper, indium tin oxide (ITO) and hybrid ITO/SiO(2) nanopillars are employed as three-dimensional high surface area transparent electrodes in OPVs. The nanopillar arrays are fabricated via glancing angle deposition (GLAD) and electrochemically modified with nanofibrous PEDOT:PSS (poly(3,4-ethylenedioxythiophene):poly(p-styrenesulfonate)). The structures are found to have increased surface area as characterized by porosimetry. When applied as anodes in polymer/fullerene OPVs (architecture: commercial ITO/GLAD ITO/PEDOT:PSS/P3HT:PCBM/Al, where P3HT is 2,5-diyl-poly(3-hexylthiophene) and PCBM is [6,6]-phenyl-C(61)-butyric acid methyl ester), the air-processed solar cells incorporating high surface area, PEDOT:PSS-modified ITO nanoelectrode arrays operate with improved performance relative to devices processed identically on unstructured, commercial ITO substrates. The resulting power conversion efficiency is 2.2% which is a third greater than for devices prepared on commercial ITO. To further refine the structure, insulating SiO(2) caps are added above the GLAD ITO nanopillars to produce a hybrid ITO/SiO(2) nanoelectrode. OPV devices based on this system show reduced electrical shorting and series resistance, and as a consequence, a further improved power conversion efficiency of 2.5% is recorded.
RESUMO
A new genus, Graziasternum gen. nov., with two new species, Graziasternum graziae sp. nov. and Graziasternum joceliae sp. nov. are described. According to external thoracic and genital structures, this new genus is considered to be the closest extant relative known to the genus Placosternum Amyot Serville. Discussion of its possible phylogenetic position based on structure comparison, with the discussion on the importance of the characteristics of the thoracic sterna, the genital structures with other genera or groups of genera that share similar structures is given. Additionally, the two new species are keyed and illustrated.
Assuntos
Heterópteros , Distribuição Animal , Animais , Bornéu , Hemípteros , Heterópteros/classificação , FilogeniaRESUMO
The species of Pentatomidae known to occur north of Mexico, comprising 223 species in 68 genera, are enumerated with taxonomic notes and updated and annotated distributions. Included in this update are 126 new state records reported for 62 pentatomid species in 30 genera. The copious annotations in these distributions and attendant bibliography serve as an extensive compilation of overlooked references that might contain distributional records for other insect, especially heteropteran, species.
Assuntos
Heterópteros , Animais , MéxicoRESUMO
The new Neotropical hyaliodine Colimacoris joceliae Kim Jung, sp. nov., is described from Panama. Morphological information, including a description and diagnosis of the new species is presented with photographs. A key for the identification of the species of Colimacoris is also provided.
Assuntos
Heterópteros , Animais , Heterópteros/anatomia & histologia , Heterópteros/classificação , Panamá , Especificidade da EspécieRESUMO
Two new species of Tingidae are described from Panama: Acanthotingis deltoides sp. nov. and Stephanitis joceliae sp. nov. Descriptions and diagnosis for both Acanthotingis Monte and Stephanitis Stål are provided, and a key is given for the separation of the two known species of Acanthotingis. This is the first record of both genera from Panama. A checklist of all Neotropical species of both genera is presented.
Assuntos
Heterópteros , Animais , Heterópteros/anatomia & histologia , Heterópteros/classificação , Panamá , Especificidade da EspécieRESUMO
The genus Acrophyma Bergroth currently contains two species, the Andean A. cumingii (Westwood) and the Neotropical A. bicallosa (Stål). The examination of types and new material revealed that among the Neotropical species the Brazilian population differs from the Colombian, and the first one belongs to a new species in this group. A morphological analysis of the genus indicated the Neotropical species are different from the Andean species. According to the current most used generic characters in acanthosomatids, Neotropical species should be placed in a new genus. This is also supported by biogeographical relationships. New distributional records for the species of this group are provided.
Assuntos
Heterópteros , Distribuição Animal , Animais , Hemípteros , Heterópteros/classificaçãoRESUMO
Plastics have long been an environmental contaminant of concern as both large-scale plastic debris and as micro- and nano-plastics with demonstrated wide-scale ubiquity. Research in the past decade has focused on the potential toxicological risks posed by microplastics, as well as their unique fate and transport brought on by their colloidal nature. These efforts have been slowed by the lack of analytical techniques with sufficient sensitivity and selectivity to adequately detect and characterize these contaminants in environmental and biological matrices. To improve analytical analyses, microplastic tracers are developed with recognizable isotopic, metallic, or fluorescent signatures capable of being identified amidst a complex background. Here we describe the synthesis, characterization, and application of a novel synthetic copolymer nanoplastic based on polystyrene (PS) and poly(2-vinylpyridine) (P2VP) intercalated with gold, platinum or palladium nanoparticles that can be capped with different polymeric shells meant to mimic the intended microplastic. In this work, particles with PS and polymethylmethacrylate (PMMA) shells are used to examine the behavior of microplastic particles in estuarine sediment and coastal waters. The micro- and nanoplastic tracers, with sizes between 300 and 500 nm in diameter, were characterized using multiple physical, chemical, and colloidal analysis techniques. The metallic signatures of the tracers allow for quantification by both bulk and single-particle inductively-coupled plasma mass spectrometry (ICP-MS and spICP-MS, respectively). As a demonstration of environmental applicability, the tracers were equilibrated with sediment collected from Bellingham Bay, WA, United States to determine the degree to which microplastics bind and sink in an estuary based of grain size and organic carbon parameters. In these experiments, between 80 and 95% of particles were found to associate with the sediment, demonstrative of estuaries being a major anticipated sink for these contaminants. These materials show considerable promise in their versatility, potential for multiplexing, and utility in studying micro- and nano-plastic transport in real-world environments.
RESUMO
The glancing angle deposition (GLAD) technique is used to fabricate nanostructured thin films with high surface area. Quantifying this property is important for optimizing GLAD-based device performance. Our group has used high-sensitivity krypton gas adsorption and the complementary technique of cyclic voltammetry to measure surface area as a function of deposition angle, thickness, and morphological characteristics for several metal oxide thin films. In this work, we studied amorphous titanium dioxide (TiO(2)), amorphous silicon dioxide (SiO(2)), and polycrystalline indium tin oxide (ITO) nanostructures with vertical and helical post morphologies over a range of oblique deposition angles from 0 to 86 degrees. Krypton gas sorption isotherms, evaluated using the Brunauer-Emmettt-Teller (BET) method, revealed maximum surface area enhancements of 880 +/- 110, 980 +/- 125, and 210 +/- 30 times the footprint area (equivalently 300 +/- 40, 570 +/- 70, and 50 +/- 6 m(2) g(-1)) for vertical posts TiO(2), SiO(2), and ITO. We also applied the cyclic voltammetry technique to these ITO films and observed the same overall trends as seen with the BET method. In addition, we applied the BET method to the measurement of helical films and found that the surface area trend was shifted with respect to that of vertical post films. This revealed the important influence of the substrate rotation rate and film morphology on surface properties. Finally, we showed that the surface area scales linearly with film thickness, with slopes of 730 +/- 35 to 235 +/- 10 m(2) m(-2) microm(-1) found for titania vertical post films deposited at angles from 70 to 85 degrees. This characterization effort will allow for the optimization of solar, photonic, and sensing devices fabricated from thin metal oxide films using GLAD.
RESUMO
Sibaria Stål is a genus of Pentatomidae occurring exclusively in the Neotropical region. Since its description, little information has been added to the knowledge of the taxon. The hypothesis of monophyly of Sibaria was recently supported by a phylogenetic analysis based on morphological and molecular data. The purpose of this study is to provide a review of Sibaria, redescribe the valid species, and describe a new species. The genus includes four species: S. andicola Breddin, S. armata (Dallas), S. englemani Rolston, and S. amazonica sp. nov.. Diagnoses, macrophotographs (habitus, external and internal genitalia), an identification key, and distribution records of the species are also provided.
Assuntos
Heterópteros , Animais , FilogeniaRESUMO
Multipotent mesenchymal stem cells (MSCs), first identified in the bone marrow, have subsequently been found in many other tissues, including fat, cartilage, muscle, and bone. Adipose tissue has been identified as an alternative to bone marrow as a source for the isolation of MSCs, as it is neither limited in volume nor as invasive in the harvesting. This study compares the multipotentiality of bone marrow-derived mesenchymal stem cells (BMSCs) with that of adipose-derived mesenchymal stem cells (AMSCs) from 12 age- and sex-matched donors. Phenotypically, the cells are very similar, with only three surface markers, CD106, CD146, and HLA-ABC, differentially expressed in the BMSCs. Although colony-forming units-fibroblastic numbers in BMSCs were higher than in AMSCs, the expression of multiple stem cell-related genes, like that of fibroblast growth factor 2 (FGF2), the Wnt pathway effectors FRAT1 and frizzled 1, and other self-renewal markers, was greater in AMSCs. Furthermore, AMSCs displayed enhanced osteogenic and adipogenic potential, whereas BMSCs formed chondrocytes more readily than AMSCs. However, by removing the effects of proliferation from the experiment, AMSCs no longer out-performed BMSCs in their ability to undergo osteogenic and adipogenic differentiation. Inhibition of the FGF2/fibroblast growth factor receptor 1 signaling pathway demonstrated that FGF2 is required for the proliferation of both AMSCs and BMSCs, yet blocking FGF2 signaling had no direct effect on osteogenic differentiation. Disclosure of potential conflicts of interest is found at the end of this article.
Assuntos
Tecido Adiposo/citologia , Fator 2 de Crescimento de Fibroblastos/farmacologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Pluripotentes/citologia , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/fisiologia , Adulto , Células da Medula Óssea/citologia , Células da Medula Óssea/fisiologia , Técnicas de Cultura de Células , Diferenciação Celular , Ensaio de Unidades Formadoras de Colônias , DNA/análise , DNA/genética , Citometria de Fluxo , Regulação da Expressão Gênica , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/fisiologia , Osteogênese/fisiologia , Células-Tronco Pluripotentes/efeitos dos fármacos , Células-Tronco Pluripotentes/fisiologia , Reação em Cadeia da PolimeraseRESUMO
Zanolimumab is a human IgG1 antibody against CD4, which is in clinical development for the treatment of cutaneous and nodal T-cell lymphomas. Here, we report on its mechanisms of action. Zanolimumab was found to inhibit CD4+ T cells by combining signaling inhibition with the induction of Fc-dependent effector mechanisms. First, T-cell receptor (TCR) signal transduction is inhibited by zanolimumab through a fast, dual mechanism, which is activated within minutes. Ligation of CD4 by zanolimumab effectively inhibits early TCR signaling events but, interestingly, activates signaling through the CD4-associated tyrosine kinase p56lck. An uncoupling of p56lck from the TCR by anti-CD4 allows the kinase to transmit direct inhibitory signals via the inhibitory adaptor molecules Dok-1 and SHIP-1. Second, CD4+ T cells are killed by induction of antibody-dependent cell-mediated cytotoxicity, to which CD45RO+ cells are more sensitive than CD45RA+ cells. Finally, zanolimumab induces down-modulation of CD4 from cell surfaces via a slow Fc-dependent mechanism. In conclusion, zanolimumab rapidly inhibits T-cell signaling via a dual mechanism of action combined with potent Fc-dependent lysis of CD4+ T cells and may act long-term by down-regulating CD4.
Assuntos
Anticorpos Monoclonais/farmacologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfoma Cutâneo de Células T/imunologia , Linfoma Cutâneo de Células T/terapia , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Citotoxicidade Celular Dependente de Anticorpos , Complexo CD3/imunologia , Antígenos CD4/biossíntese , Antígenos CD4/genética , Antígenos CD4/imunologia , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/imunologia , Método Duplo-Cego , Regulação para Baixo , Humanos , Inositol Polifosfato 5-Fosfatases , Ativação Linfocitária/efeitos dos fármacos , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/metabolismo , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases , Monoéster Fosfórico Hidrolases/metabolismo , Fosforilação , Psoríase/imunologia , Psoríase/terapia , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
The aeptine Mariomella singularis gen. et sp. nov. is described and illustrated from Western Australia. With this new addition, the Aeptini diversity increases to 21 species in nine genera.