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1.
Proc Natl Acad Sci U S A ; 119(20): e2111294119, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35537050

RESUMO

To meet the 1.5 °C target, methane (CH4) from ruminants must be reduced by 11 to 30% by 2030 and 24 to 47% by 2050 compared to 2010 levels. A meta-analysis identified strategies to decrease product-based (PB; CH4 per unit meat or milk) and absolute (ABS) enteric CH4 emissions while maintaining or increasing animal productivity (AP; weight gain or milk yield). Next, the potential of different adoption rates of one PB or one ABS strategy to contribute to the 1.5 °C target was estimated. The database included findings from 430 peer-reviewed studies, which reported 98 mitigation strategies that can be classified into three categories: animal and feed management, diet formulation, and rumen manipulation. A random-effects meta-analysis weighted by inverse variance was carried out. Three PB strategies­namely, increasing feeding level, decreasing grass maturity, and decreasing dietary forage-to-concentrate ratio­decreased CH4 per unit meat or milk by on average 12% and increased AP by a median of 17%. Five ABS strategies­namely CH4 inhibitors, tanniferous forages, electron sinks, oils and fats, and oilseeds­decreased daily methane by on average 21%. Globally, only 100% adoption of the most effective PB and ABS strategies can meet the 1.5 °C target by 2030 but not 2050, because mitigation effects are offset by projected increases in CH4 due to increasing milk and meat demand. Notably, by 2030 and 2050, low- and middle-income countries may not meet their contribution to the 1.5 °C target for this same reason, whereas high-income countries could meet their contributions due to only a minor projected increase in enteric CH4 emissions.


Assuntos
Metano , Ruminantes , África , Animais , Países em Desenvolvimento , Europa (Continente) , Aquecimento Global/prevenção & controle , Metano/análise
2.
Cancer Immunol Immunother ; 73(1): 8, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38231344

RESUMO

Bone marrow mesenchymal stromal cells (MSCs) have been described as potent regulators of T-cell function, though whether they could impede the effectiveness of immunotherapy against acute myeloid leukemia (AML) is still under investigation. We examine whether they could interfere with the activity of leukemia-specific clonal cytotoxic T-lymphocytes (CTLs) and chimeric antigen receptor (CAR) T cells, as well as whether the immunomodulatory properties of MSCs could be associated with the induction of T-cell senescence. Co-cultures of leukemia-associated Wilm's tumor protein 1 (WT1) and tyrosine-protein kinase transmembrane receptor 1 (ROR1)-reactive CTLs and of CD123-redirected switchable CAR T cells were prepared in the presence of MSCs and assessed for cytotoxic potential, cytokine secretion, and expansion. T-cell senescence within functional memory sub-compartments was investigated for the senescence-associated phenotype CD28-CD57+ using unmodified peripheral blood mononuclear cells. We describe inhibition of expansion of AML-redirected switchable CAR T cells by MSCs via indoleamine 2,3-dioxygenase 1 (IDO-1) activity, as well as reduction of interferon gamma (IFNγ) and interleukin-2 (IL-2) release. In addition, MSCs interfered with the secretory potential of leukemia-associated WT1- and ROR1-targeting CTL clones, inhibiting the release of IFNγ, tumor necrosis factor alpha, and IL-2. Abrogated T cells were shown to retain their cytolytic activity. Moreover, we demonstrate induction of a CD28loCD27loCD57+KLRG1+ senescent T-cell phenotype by MSCs. In summary, we show that MSCs are potent modulators of anti-leukemic T cells, and targeting their modes of action would likely be beneficial in a combinatorial approach with AML-directed immunotherapy.


Assuntos
Leucemia Mieloide Aguda , Células-Tronco Mesenquimais , Humanos , Medula Óssea , Interleucina-2 , Antígenos CD28 , Leucócitos Mononucleares , Leucemia Mieloide Aguda/terapia , Linfócitos T Citotóxicos , Células Clonais
3.
Chemistry ; 30(32): e202400366, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38506263

RESUMO

Discussed are two picolinate appended bispidine ligands (3,7-diazabicyclo[3.3.1]nonane derivatives) in comparison with an earlier described bis-pyridine derivative, which are all known to strongly bind CuII. The radiopharmacological characterization of the two isomeric bispidine complexes includes quantitative labeling with 64CuII at ambient conditions with high radiochemical purities and yields (molar activities >200 MBq/nmol). Challenge experiments in presence of EDTA, cyclam, human serum and SOD demonstrate high stability and inertness of the 64Cu-bispidine complexes. Biodistribution studies performed in Wistar rats indicate a rapid renal elimination for both 64Cu-labeled chelates. The bispidine ligand with the picolinate group in N7 position was selected for further biological experiments, and its backbone was therefore substituted with a benzyl-NCS group at C9. Two tumor target modules (TMs), targeting prostate stem cell antigen (PSCA), overexpressed in prostate cancer, and the fibroblast activation protein (FAP) in fibrosarcoma, were selected for thiourea coupling with the NCS-functionalized ligand and lysine residues of TMs. Small animal PET experiments on tumor-bearing mice showed specific accumulation of the 64Cu-labeled TMs in PSCA- and FAP-overexpressing tumors (standardized uptake value (SUV) for PC3: 2.7±0.6 and HT1080: 7.2±1.25) with almost no uptake in wild type tumors.


Assuntos
Radioisótopos de Cobre , Imunoconjugados , Ácidos Picolínicos , Ratos Wistar , Ácidos Picolínicos/química , Animais , Ratos , Radioisótopos de Cobre/química , Humanos , Imunoconjugados/química , Imunoconjugados/farmacocinética , Camundongos , Distribuição Tecidual , Compostos Radiofarmacêuticos/química , Ligantes , Masculino , Tomografia por Emissão de Pósitrons , Complexos de Coordenação/química , Compostos Bicíclicos Heterocíclicos com Pontes
4.
Int J Mol Sci ; 25(13)2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-39000348

RESUMO

Although Chimeric Antigen Receptor (CAR) T-cells have shown high efficacy in hematologic malignancies, they can cause severe to life-threatening side effects. To address these safety concerns, we have developed adaptor CAR platforms, like the UniCAR system. The redirection of UniCAR T-cells to target cells relies on a Target Module (TM), containing the E5B9 epitope and a tumor-specific binding moiety. Appropriate UniCAR-T activation thus involves two interactions: between the TM and the CAR T-cell, and the TM and the target cell. Here, we investigate if and how alterations of the amino acid sequence of the E5B9 UniCAR epitope impact the interaction between TMs and the UniCAR. We identify the new epitope E5B9L, for which the monoclonal antibody 5B9 has the greatest affinity. We then integrate the E5B9L peptide in previously established TMs directed to Fibroblast Activation Protein (FAP) and assess if such changes in the UniCAR epitope of the TMs affect UniCAR T-cell potency. Binding properties of the newly generated anti-FAP-E5B9L TMs to UniCAR and their ability to redirect UniCAR T-cells were compared side-by-side with the ones of anti-FAP-E5B9 TMs. Despite a substantial variation in the affinity of the different TMs to the UniCAR, no significant differences were observed in the cytotoxic and cytokine-release profiles of the redirected T-cells. Overall, our work indicates that increasing affinity of the UniCAR to the TM does not play a crucial role in such adaptor CAR system, as it does not significantly impact the potency of the UniCAR T-cells.


Assuntos
Receptores de Antígenos Quiméricos , Linfócitos T , Humanos , Receptores de Antígenos Quiméricos/imunologia , Receptores de Antígenos Quiméricos/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Imunoterapia Adotiva/métodos , Epitopos/imunologia , Linhagem Celular Tumoral , Anticorpos Monoclonais/imunologia
5.
Cancer Immunol Immunother ; 72(9): 2905-2918, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36688995

RESUMO

Chimeric antigen receptor (CAR)-engineered immune effector cells constitute a promising approach for adoptive cancer immunotherapy. Nevertheless, on-target/off-tumor toxicity and immune escape due to antigen loss represent considerable challenges. These may be overcome by adaptor CARs that are selectively triggered by bispecific molecules that crosslink the CAR with a tumor-associated surface antigen. Here, we generated NK cells carrying a first- or second-generation universal CAR (UniCAR) and redirected them to tumor cells with so-called target modules (TMs) which harbor an ErbB2 (HER2)-specific antibody domain for target cell binding and the E5B9 peptide recognized by the UniCAR. To investigate differential effects of the protein design on activity, we developed homodimeric TMs with one, two or three E5B9 peptides per monomer, and binding domains either directly linked or separated by an IgG4 Fc domain. The adaptor molecules were expressed as secreted proteins in Expi293F cells, purified from culture supernatants and their bispecific binding to UniCAR and ErbB2 was confirmed by flow cytometry. In cell killing experiments, all tested TMs redirected NK cell cytotoxicity selectively to ErbB2-positive tumor cells. Nevertheless, we found considerable differences in the extent of specific cell killing depending on TM design and CAR composition, with adaptor proteins carrying two or three E5B9 epitopes being more effective when combined with NK cells expressing the first-generation UniCAR, while the second-generation UniCAR was more active in the presence of TMs with one E5B9 sequence. These results may have important implications for the further development of optimized UniCAR and target module combinations for cancer immunotherapy.


Assuntos
Neoplasias , Receptores de Antígenos Quiméricos , Humanos , Receptores de Antígenos Quiméricos/genética , Células Matadoras Naturais , Neoplasias/terapia , Imunoterapia Adotiva/métodos , Antígenos de Neoplasias , Linhagem Celular Tumoral , Receptor ErbB-2
6.
Int J Mol Sci ; 24(11)2023 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-37298374

RESUMO

Prostate specific membrane antigen (PSMA) is an excellent target for imaging and treatment of prostate carcinoma (PCa). Unfortunately, not all PCa cells express PSMA. Therefore, alternative theranostic targets are required. The membrane protein prostate stem cell antigen (PSCA) is highly overexpressed in most primary prostate carcinoma (PCa) cells and in metastatic and hormone refractory tumor cells. Moreover, PSCA expression positively correlates with tumor progression. Therefore, it represents a potential alternative theranostic target suitable for imaging and/or radioimmunotherapy. In order to support this working hypothesis, we conjugated our previously described anti-PSCA monoclonal antibody (mAb) 7F5 with the bifunctional chelator CHX-A″-DTPA and subsequently radiolabeled it with the theranostic radionuclide 177Lu. The resulting radiolabeled mAb ([177Lu]Lu-CHX-A″-DTPA-7F5) was characterized both in vitro and in vivo. It showed a high radiochemical purity (>95%) and stability. The labelling did not affect its binding capability. Biodistribution studies showed a high specific tumor uptake compared to most non-targeted tissues in mice bearing PSCA-positive tumors. Accordingly, SPECT/CT images revealed a high tumor-to-background ratios from 16 h to 7 days after administration of [177Lu]Lu-CHX-A″-DTPA-7F5. Consequently, [177Lu]Lu-CHX-A″-DTPA-7F5 represents a promising candidate for imaging and in the future also for radioimmunotherapy.


Assuntos
Carcinoma , Ácido Pentético , Animais , Camundongos , Masculino , Ácido Pentético/química , Distribuição Tecidual , Próstata , Linhagem Celular Tumoral , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais/química , Células-Tronco , Carcinoma/tratamento farmacológico , Lutécio/química
7.
J Dairy Sci ; 105(12): 9297-9326, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36270879

RESUMO

Ruminant livestock are an important source of anthropogenic methane (CH4). Decreasing the emissions of enteric CH4 from ruminant production is strategic to limit the global temperature increase to 1.5°C by 2050. Research in the area of enteric CH4 mitigation has grown exponentially in the last 2 decades, with various strategies for enteric CH4 abatement being investigated: production intensification, dietary manipulation (including supplementation and processing of concentrates and lipids, and management of forage and pastures), rumen manipulation (supplementation of ionophores, 3-nitrooxypropanol, macroalgae, alternative electron acceptors, and phytochemicals), and selection of low-CH4-producing animals. Other enteric CH4 mitigation strategies are at earlier stages of research but rapidly developing. Herein, we discuss and analyze the current status of available enteric CH4 mitigation strategies with an emphasis on opportunities and barriers to their implementation in confined and partial grazing production systems, and in extensive and fully grazing production systems. For each enteric CH4 mitigation strategy, we discuss its effectiveness to decrease total CH4 emissions and emissions on a per animal product basis, safety issues, impacts on the emissions of other greenhouse gases, as well as other economic, regulatory, and societal aspects that are key to implementation. Most research has been conducted with confined animals, and considerably more research is needed to develop, adapt, and evaluate antimethanogenic strategies for grazing systems. In general, few options are currently available for extensive production systems without feed supplementation. Continuous research and development are needed to develop enteric CH4 mitigation strategies that are locally applicable. Information is needed to calculate carbon footprints of interventions on a regional basis to evaluate the impact of mitigation strategies on net greenhouse gas emissions. Economically affordable enteric CH4 mitigation solutions are urgently needed. Successful implementation of safe and effective antimethanogenic strategies will also require delivery mechanisms and adequate technical support for producers, as well as consumer involvement and acceptance. The most appropriate metrics should be used in quantifying the overall climate outcomes associated with mitigation of enteric CH4 emissions. A holistic approach is required, and buy-in is needed at all levels of the supply chain.


Assuntos
Gases de Efeito Estufa , Metano , Animais , Metano/análise , Biodiversidade , Temperatura , Ruminantes
8.
Int J Mol Sci ; 23(9)2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35563312

RESUMO

Chimeric antigen receptor (CAR)-expressing T-cells are without a doubt a breakthrough therapy for hematological malignancies. Despite their success, clinical experience has revealed several challenges, which include relapse after targeting single antigens such as CD19 in the case of B-cell acute lymphoblastic leukemia (B-ALL), and the occurrence of side effects that could be severe in some cases. Therefore, it became clear that improved safety approaches, and targeting multiple antigens, should be considered to further improve CAR T-cell therapy for B-ALL. In this paper, we address both issues by investigating the use of CD10 as a therapeutic target for B-ALL with our switchable UniCAR system. The UniCAR platform is a modular platform that depends on the presence of two elements to function. These include UniCAR T-cells and the target modules (TMs), which cross-link the T-cells to their respective targets on tumor cells. The TMs function as keys that control the switchability of UniCAR T-cells. Here, we demonstrate that UniCAR T-cells, armed with anti-CD10 TM, can efficiently kill B-ALL cell lines, as well as patient-derived B-ALL blasts, thereby highlighting the exciting possibility for using CD10 as an emerging therapeutic target for B-cell malignancies.


Assuntos
Leucemia de Células B , Leucemia Linfocítica Crônica de Células B , Neprilisina , Antígenos CD19/metabolismo , Humanos , Imunoterapia Adotiva , Leucemia de Células B/metabolismo , Leucemia de Células B/terapia , Leucemia Linfocítica Crônica de Células B/metabolismo , Leucemia Linfocítica Crônica de Células B/terapia , Neprilisina/uso terapêutico , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T
9.
Int J Mol Sci ; 23(14)2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35887271

RESUMO

Radiation of tumor cells can lead to the selection and outgrowth of tumor escape variants. As radioresistant tumor cells are still sensitive to retargeting of T cells, it appears promising to combine radio- with immunotherapy keeping in mind that the radiation of tumors favors the local conditions for immunotherapy. However, radiation of solid tumors will not only hit the tumor cells but also the infiltrated immune cells. Therefore, we wanted to learn how radiation influences the functionality of T cells with respect to retargeting to tumor cells via a conventional bispecific T cell engager (BiTE) and our previously described modular BiTE format UNImAb. T cells were irradiated between 2 and 50 Gy. Low dose radiation of T cells up to about 20 Gy caused an increased release of the cytokines IL-2, TNF and interferon-γ and an improved capability to kill target cells. Although radiation with 50 Gy strongly reduced the function of the T cells, it did not completely abrogate the functionality of the T cells.


Assuntos
Anticorpos Biespecíficos , Neoplasias da Próstata , Humanos , Fatores Imunológicos , Imunoterapia/métodos , Masculino , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/radioterapia , Linfócitos T
10.
Agron Sustain Dev ; 42(5): 101, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36254245

RESUMO

Ways are being sought to reduce the environmental impact of ruminant livestock farming. Integration of trees into farming systems has been advocated as a measure to deliver ecosystem services, inter alia climate regulation and adaptation, water quality regulation, provisioning of fibre, fuel and habitats to support biodiversity. Despite the rapid expansion of cattle farming in the tropics, notably in Latin America, there is little robust evidence on the extent to which trees are able to mitigate the effects of cattle farming in this ecological zone. This article describes a case study conducted on a large, specialised dairy farm in Costa Rica, where two-thirds of the field boundaries are live tree fences. For the first time, this study quantifies the offset potential of trees by estimating rate of carbon sequestration in a silvopastoral system (SPS) in the tropics. It was found that over a 30-month interval, trees sequestered 1.43 Mg C ha-1 year-1 above and below ground. Attributional life cycle assessment (LCA) (cradle to farm gate) was applied to calculate the carbon footprint of milk produced on the farm for the years 2016 to 2018. Trees in live fences offset 21-37% of milk footprints, resulting in residual net footprints of 0.75±0.25 to 0.84±0.26 kg CO2 eq. kg-1 milk. Exclusion of life cycle emissions that may not fall within national emission inventory accounting (e.g. fertiliser manufacture and feed production) increased the mean offset from 27 to 34% of gross milk footprint. Although based on temporally limited data (30 months), our findings indicate that a live fence SPS could play an important role in short- to medium-term climate mitigation from livestock production, buying time for deployment of long-term mitigation and adaptation planning. Supplementary Information: The online version contains supplementary material available at 10.1007/s13593-022-00834-z.

11.
J Immunol ; 202(6): 1735-1746, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30728213

RESUMO

Long-term survival of adoptively transferred chimeric Ag receptor (CAR) T cells is often limited. Transplantation of hematopoietic stem cells (HSCs) transduced to express CARs could help to overcome this problem as CAR-armed HSCs can continuously deliver CAR+ multicell lineages (e.g., T cells, NK cells). In dependence on the CAR construct, a variable extent of tonic signaling in CAR T cells was reported; thus, effects of CAR-mediated tonic signaling on the hematopoiesis of CAR-armed HSCs is unclear. To assess the effects of tonic signaling, two CAR constructs were established and analyzed 1) a signaling CAR inducing a solid Ag-independent tonic signaling termed CAR-28/ζ and 2) a nonstimulating control CAR construct lacking intracellular signaling domains termed CAR-Stop. Bone marrow cells from immunocompetent mice were isolated, purified for HSC-containing Lin-cKit+ cells or the Lin-cKit+ Sca-1+ subpopulation (Lin-Sca-1+cKit+), and transduced with both CAR constructs. Subsequently, modified bone marrow cells were transferred into irradiated mice, in which they successfully engrafted and differentiated into hematopoietic progenitors. HSCs expressing the CAR-Stop sustained normal hematopoiesis. In contrast, expression of the CAR-28/ζ led to elimination of mature CAR+ T and B cells, suggesting that the CAR-mediated tonic signaling mimics autorecognition via the newly recombined immune receptors in the developing lymphocytes.


Assuntos
Células-Tronco Hematopoéticas/metabolismo , Ativação Linfocitária/fisiologia , Linfopoese/fisiologia , Receptores de Antígenos Quiméricos/metabolismo , Transdução de Sinais/fisiologia , Transferência Adotiva , Animais , Diferenciação Celular/fisiologia , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Camundongos , Camundongos Endogâmicos C57BL
12.
Int J Mol Sci ; 22(21)2021 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-34769474

RESUMO

The anti-La mab 312B, which was established by hybridoma technology from human-La transgenic mice after adoptive transfer of anti-human La T cells, immunoprecipitates both native eukaryotic human and murine La protein. Therefore, it represents a true anti-La autoantibody. During maturation, the anti-La mab 312B acquired somatic hypermutations (SHMs) which resulted in the replacement of four aa in the complementarity determining regions (CDR) and seven aa in the framework regions. The recombinant derivative of the anti-La mab 312B in which all the SHMs were corrected to the germline sequence failed to recognize the La antigen. We therefore wanted to learn which SHM(s) is (are) responsible for anti-La autoreactivity. Humanization of the 312B ab by grafting its CDR regions to a human Ig backbone confirms that the CDR sequences are mainly responsible for anti-La autoreactivity. Finally, we identified that a single amino acid replacement (D > Y) in the germline sequence of the CDR3 region of the heavy chain of the anti-La mab 312B is sufficient for anti-La autoreactivity.


Assuntos
Anticorpos Antinucleares/genética , Autoanticorpos/genética , Hipermutação Somática de Imunoglobulina/genética , Sequência de Aminoácidos , Aminoácidos/genética , Aminoácidos/metabolismo , Anticorpos Antinucleares/imunologia , Anticorpos Antinucleares/metabolismo , Autoanticorpos/química , Autoanticorpos/imunologia , Autoanticorpos/metabolismo , Autoimunidade/genética , Regiões Determinantes de Complementaridade/genética , Regiões Determinantes de Complementaridade/imunologia , Regiões Determinantes de Complementaridade/metabolismo , Epitopos/genética , Epitopos/imunologia , Células HeLa , Humanos , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/metabolismo , Análise de Sequência de Proteína
13.
Int J Mol Sci ; 22(3)2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33530489

RESUMO

Since the first description of nuclear autoantigens in the late 1960s and early 1970s, researchers, including ourselves, have found it difficult to establish monoclonal antibodies (mabs) against nuclear antigens, including the La/SS-B (Sjögrens' syndrome associated antigen B) autoantigen. To date, only a few anti-La mabs have been derived by conventional hybridoma technology; however, those anti-La mabs were not bona fide autoantibodies as they recognize either human La specific, cryptic, or post-translationally modified epitopes which are not accessible on native mouse La protein. Herein, we present a series of novel murine anti-La mabs including truly autoreactive ones. These mabs were elicited from a human La transgenic animal through adoptive transfer of T cells from non-transgenic mice immunized with human La antigen. Detailed epitope and paratope analyses experimentally confirm the hypothesis that somatic hypermutations that occur during T cell dependent maturation can lead to autoreactivity to the nuclear La/SS-B autoantigen.


Assuntos
Autoantígenos/imunologia , Autoimunidade/genética , Linfócitos B/imunologia , Linfócitos B/metabolismo , Comunicação Celular/imunologia , Ribonucleoproteínas/imunologia , Hipermutação Somática de Imunoglobulina , Linfócitos T/imunologia , Células 3T3 , Transferência Adotiva , Sequência de Aminoácidos , Animais , Especificidade de Anticorpos/genética , Autoanticorpos/química , Autoanticorpos/genética , Autoanticorpos/imunologia , Autoantígenos/química , Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , Doenças Autoimunes/metabolismo , Modelos Animais de Doenças , Mapeamento de Epitopos , Epitopos/química , Epitopos/imunologia , Imunofluorescência , Células Germinativas/metabolismo , Humanos , Imunização , Camundongos , Camundongos Transgênicos , Modelos Moleculares , Conformação Proteica , Ribonucleoproteínas/química , Linfócitos T/metabolismo , Antígeno SS-B
14.
Int J Mol Sci ; 22(18)2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34575862

RESUMO

Decades ago, we and many other groups showed a nucleo-cytoplasmic translocation of La protein in cultured cells. This shuttling of La protein was seen after UV irradiation, virus infections, hydrogen peroxide exposure and the Fenton reaction based on iron or copper ions. All of these conditions are somehow related to oxidative stress. Unfortunately, these harsh conditions could also cause an artificial release of La protein. Even until today, the shuttling and the cytoplasmic function of La/SS-B is controversially discussed. Moreover, the driving mechanism for the shuttling of La protein remains unclear. Recently, we showed that La protein undergoes redox-dependent conformational changes. Moreover, we developed anti-La monoclonal antibodies (anti-La mAbs), which are specific for either the reduced form of La protein or the oxidized form. Using these tools, here we show that redox-dependent conformational changes are the driving force for the shuttling of La protein. Moreover, we show that translocation of La protein to the cytoplasm can be triggered in a ligand/receptor-dependent manner under physiological conditions. We show that ligands of toll-like receptors lead to a redox-dependent shuttling of La protein. The shuttling of La protein depends on the redox status of the respective cell type. Endothelial cells are usually resistant to the shuttling of La protein, while dendritic cells are highly sensitive. However, the deprivation of intracellular reducing agents in endothelial cells makes endothelial cells sensitive to a redox-dependent shuttling of La protein.


Assuntos
Transporte Ativo do Núcleo Celular , Autoantígenos/química , Núcleo Celular/metabolismo , Oxigênio/química , Ribonucleoproteínas/química , Anticorpos Monoclonais/química , Citoplasma/metabolismo , Epitopos/química , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Humanos , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/metabolismo , Óxido Nítrico/metabolismo , Oxirredução , Conformação Proteica , Transdução de Sinais , Síndrome de Sjogren/imunologia , Síndrome de Sjogren/metabolismo , Raios Ultravioleta , Antígeno SS-B
15.
Int J Mol Sci ; 22(7)2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33806091

RESUMO

According to the literature, the autoantigen La is involved in Cap-independent translation. It was proposed that one prerequisite for this function is the formation of a protein dimer. However, structural analyses argue against La protein dimers. Noteworthy to mention, these structural analyses were performed under reducing conditions. Here we describe that La protein can undergo redox-dependent structural changes. The oxidized form of La protein can form dimers, oligomers and even polymers stabilized by disulfide bridges. The primary sequence of La protein contains three cysteine residues. Only after mutation of all three cysteine residues to alanine La protein becomes insensitive to oxidation, indicating that all three cysteines are involved in redox-dependent structural changes. Biophysical analyses of the secondary structure of La protein support the redox-dependent conformational changes. Moreover, we identified monoclonal anti-La antibodies (anti-La mAbs) that react with either the reduced or oxidized form of La protein. Differential reactivities to the reduced and oxidized form of La protein were also found in anti-La sera of autoimmune patients.


Assuntos
Autoantígenos/química , Oxirredução , Ribonucleoproteínas/química , Síndrome de Sjogren/imunologia , Anticorpos Antinucleares , Autoanticorpos/imunologia , Autoimunidade , Citocinas/metabolismo , Dissulfetos/química , Epitopos/química , Humanos , Lúpus Eritematoso Sistêmico/imunologia , Oxigênio/química , Polímeros/química , Multimerização Proteica , Estrutura Secundária de Proteína , RNA/química , Proteínas de Ligação a RNA/imunologia , Proteínas Recombinantes/química , Temperatura , Antígeno SS-B
16.
Trop Anim Health Prod ; 54(1): 15, 2021 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-34905115

RESUMO

The study reviewed carbon footprint (CF) analyses for milk production in Latin America from cradle to farm gate. The objective was to estimate (1) the effect of feeding management (zero-grazing, semi-confinement, and pasture), (2) cattle system (specialized dairy vs. dual-purpose), and (3) region (tropical vs. temperate) on milk production (kg/cow/day) and CF (kg CO2eq/kg fat and protein corrected milk (FPCM)). A systematic literature review was conducted, and for the final analysis, a total of 32 individual CF (from 11 studies) were used. Studies included in the final analysis allowed to calculate CF per kg FPCM, included upstream emissions calculations, and used the IPCC's tier 2 approach for enteric methane emissions. The range of the CF observed in the region was from 1.54 to 3.57 kg CO2eq/kg FPCM. Feeding management had a significant effect on milk production, but not on CF. Zero-grazing compared with pasture systems had a 140% greater milk production (20.1 vs. 8.4 kg milk/cow/day), but numerically greater CF for pasture systems (2.6 vs. 1.7 kg CO2eq/kg FPCM). Compared with specialized dairy cattle, dual-purpose cattle produced less milk (P < 0.001) and higher CF (P < 0.05). Compared with temperate regions, tropical region systems produced less milk and higher CF. In conclusion, in Latin America, the cattle system and region have a significant impact on CF, whereas the feeding management (zero-grazing, semi-confinement, and pasture) does not impact the CF of milk produced.


Assuntos
Pegada de Carbono , Indústria de Laticínios , Animais , Bovinos , Dieta , Feminino , Lactação , América Latina , Metano/análise , Leite/química
17.
Biol Blood Marrow Transplant ; 26(4): 691-697, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31730919

RESUMO

Radioimmunotherapy (RIT) has the potential to reduce the incidence of relapse after allogeneic hematopoietic cell transplantation (allo-HCT) in patients with advanced-stage multiple myeloma (MM). In this study, we evaluated the efficacy of RIT in combination with chemotherapy-based reduced-intensity conditioning (RIC). RIT was based on the coupling of an anti-CD66 antibody to the beta emitter 188-rhenium (188-re) for targeted bone marrow irradiation. Between 2012 and 2018, 30 patients with MM, most of them heavily pretreated with various therapies including proteasome inhibitors, immunomodulatory drugs, anti-CD38 antibodies, and autologous hematopoietic cell transplantation (auto-HCT), were treated with a RIT-RIC combination before allo-HCT. In addition to a fludarabine plus melphalan- or treosulfan-based RIC, a median dose of 18.1 Gy (interquartile range [IQR], 14.6 to 24.1 Gy) was applied to the bone marrow. After a median duration of follow-up for surviving patients of 2.1 years (IQR, 1.3 to 3.0 years), the 2-year progression-free survival and overall survival rates were 43% (95% confidence interval [CI], 26% to 73%) and 55% (95% CI, 38% to 79%), respectively. The 2-year nonrelapse mortality and cumulative incidence of progression were 17% (95% CI, 3% to 30%) and 46% (95% CI, 25% to 67%), respectively. Renal toxicity and mucositis were the most frequent extramedullary side effects. In conclusion, the addition of RIT to RIC was safe and feasible and resulted in promising outcomes compared with those previously reported for RIC-based allo-HCT without the addition of RIT in patients with relapsed/refractory MM. Nevertheless, despite the addition of RIT, relapse after allo-HCT remained a major determinant of therapeutic failure. Therefore, the development of novel RIT strategies (eg, dual targeting strategies or combinations with adapter chimeric antigen receptor T cell-based therapies) is needed.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Mieloma Múltiplo , Humanos , Mieloma Múltiplo/terapia , Recidiva Local de Neoplasia , Radioimunoterapia , Condicionamento Pré-Transplante , Transplante Homólogo
18.
J Dairy Sci ; 103(7): 6706-6715, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32448577

RESUMO

Agriculture is the largest source of ammonia (NH3) emissions. As NH3 is an indirect greenhouse gas, NH3 measurements are crucial to improving greenhouse gas emission inventory estimates. Moreover, NH3 emissions have wider implications for environmental and human health. Only a few studies have measured NH3 emissions from pastures in the tropics and subtropics and none has compared emissions to inventory estimates. The objectives of this study were to (1) measure NH3 emissions from dairy pastures in tropical and subtropical regions; (2) calculate NH3 emissions factors (EF) for each campaign; and (3) compare measured EF with those based on the 2006 Intergovernmental Panel on Climate Change (IPCC) Tier 1, 2019 Refinement to the 2006 IPCC Tier 1, and the European Monitoring and Evaluation Programme/European Environmental Agency (EMPE/EEA) Tier 2 inventory estimates. Pasture NH3 emissions were measured on 3 dairy farms in Costa Rica. On each dairy, NH3 emissions were measured twice during the wet season and once during the dry season using a micrometeorological integrated horizontal-flux mass-balance method. Emissions were measured from excreta (dung and urine) deposited by grazing cattle and the subsequent application of organic (slurry) or synthetic fertilizer (ammonium nitrate or urea). Measured EF for all campaigns [from grazing cattle excreta and any subsequent slurry or fertilizer application; 4.9 ± 0.9% of applied nitrogen (mean ± SE)] were similar to those of the EMEP/EEA Tier 2 approach (6.1 ± 0.9%; mean ± SE) and 4 times lower than 2006 IPCC and 2019 Refinement to 2006 IPCC Tier 1 default estimates (17.7 ± 1.4 and 18.2 ± 0.9%, respectively; mean ± SE). Measured EF for excreta deposited on pasture and excreta both deposited on pasture and slurry application [3.9 ± 2.1 and 4.2 ± 2.1% (mean ± 95% CI), respectively] were 5 times lower than default EF assumed by 2006 IPCC and 2019 Refinement to 2006 IPCC methodology (both 20 and 21%, respectively), whereas EMEP/EAA estimates were similar [6.0 and 4.6 ± 0.3% (mean ± 95% CI), respectively]. This suggests an overestimation of EF from excreta deposited on pasture and slurry applications in tropical and subtropical regions by IPCC methodologies. Furthermore, rainfall, which is not included as a parameter in the current EMEP/EEA Tier 2 methodology, appeared to reduce NH3 emissions, suggesting that accounting for this in the inventory methodologies could improve inventory estimates.


Assuntos
Amônia/análise , Bovinos/metabolismo , Indústria de Laticínios , Monitoramento Ambiental , Gases de Efeito Estufa/análise , Agricultura , Animais , Mudança Climática , Costa Rica , Fertilizantes/análise , Nitrogênio/análise , Estações do Ano , Clima Tropical
19.
Br J Haematol ; 186(5): 735-740, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31119728

RESUMO

Combinatory therapeutic approaches of different targeted therapies in acute myeloid leukaemia are currently under preclinical/early clinical investigation. To enhance anti-tumour effects, we combined the tyrosine kinase inhibitor (TKI) midostaurin and T-cell mediated immunotherapy directed against CD33. Clinically relevant concentrations of midostaurin abrogated T-cell mediated cytotoxicity both after activation with bispecific antibodies and chimeric antigen receptor T cells. This information is of relevance for clinicians exploring T-cell mediated immunotherapy in early clinical trials. Given the profound inhibition of T-cell functionality and anti-tumour activity, we recommend specific FLT3 TKIs for further clinical testing of combinatory approaches with T-cell based immunotherapy.


Assuntos
Antineoplásicos/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico/metabolismo , Estaurosporina/análogos & derivados , Antineoplásicos/farmacologia , Humanos , Leucemia Mieloide Aguda/patologia , Estaurosporina/farmacologia , Estaurosporina/uso terapêutico
20.
Cancer Immunol Immunother ; 68(10): 1713-1719, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31542798

RESUMO

The clinical application of immune effector cells genetically modified to express chimeric antigen receptors (CARs) has shown impressive results including complete remissions of certain malignant hematological diseases. However, their application can also cause severe side effects such as cytokine release syndrome (CRS) or tumor lysis syndrome (TLS). One limitation of currently applied CAR T cells is their lack of regulation. Especially, an emergency shutdown of CAR T cells in case of life-threatening side effects is missing. Moreover, targeting of tumor-associated antigens (TAAs) that are not only expressed on tumor cells but also on vital tissues requires the possibility of a switch allowing to repeatedly turn the activity of CAR T cells on and off. Here we summarize the development of a modular CAR variant termed universal CAR (UniCAR) system that promises to overcome these limitations of conventional CARs.


Assuntos
Imunoterapia Adotiva/métodos , Receptores de Antígenos Quiméricos/imunologia , Linfócitos T/imunologia , Humanos , Imunoterapia Adotiva/efeitos adversos , Neoplasias/terapia
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