Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 90
Filtrar
1.
J Endocr Soc ; 8(6): bvae059, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38655100

RESUMO

Context: Genetic analysis of sporadic medullary thyroid carcinoma (MTC) has revealed somatic variants in RET, RAS, and occasionally other genes. However, around 20% of patients with sporadic MTC lack a known genetic driver. Objective: To uncover potential new somatic or germline drivers, we analyze a distinct cohort of patients with sporadic, very early-onset, and aggressive MTC. Methods: Germline and somatic DNA exome sequencing was performed in 19 patients, previously tested negative for germline RET variants. Results: Exome sequencing of 19 germline samples confirmed the absence of RET and identified an NF1 pathogenic variant in 1 patient. Somatic sequencing was successful in 15 tumors revealing RET variants in 80%, predominantly p.Met918Thr, which was associated with disease aggressiveness. In RET-negative tumors, pathogenic variants were found in HRAS and NF1. The NF1 germline and somatic variants were observed in a patient without a prior clinical diagnosis of neurofibromatosis type 1, demonstrating that the loss of heterozygosity of NF1 functions as a potential MTC driver. Somatic copy number alterations analysis revealed chromosomal alterations in 53.3% of tumors, predominantly in RET-positive cases, with losses in chromosomes 9 and 22 being the most prevalent. Conclusion: This study reveals that within a cohort of early-onset nonhereditary MTC, RET remains the major driver gene. In RET-negative tumors, NF1 and RAS are drivers of sporadic MTC. In addition, in young patients without a RET germline mutation, a careful clinical evaluation with a consideration of germline NF1 gene analysis is ideal to exclude Neurofibromatosis type 1 (NF1).

2.
J Toxicol Environ Health B Crit Rev ; 27(2): 73-90, 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38247328

RESUMO

Africanized bees have spread across the Americas since 1956 and consequently resulted in human and animal deaths attributed to massive attacks related to exposure from Argentina to the USA. In Brazil, more than 100,000 accidents were registered in the last 5 years with a total of 303 deaths. To treat such massive attacks, Brazilian researchers developed the first specific antivenom against Africanized honey bee sting exposure. This unique product, the first of its kind in the world, has been safely tested in 20 patients during a Phase 2 clinical trial. To develop the antivenom, a standardized process was undertaken to extract primary venom antigens from the Africanized bees for immunization of serum-producing horses. This process involved extracting, purifying, fractionating, characterizing, and identifying the venom (apitoxin) employing mass spectrometry to generate standardized antigen for hyperimmunization of horses using the major toxins (melittin and its isoforms and phospholipase A2). The current guide describes standardization of the entire production chain of venom antigens in compliance with good manufacturing practices (GMP) required by regulatory agencies. Emphasis is placed upon the welfare of bees and horses during this process, as well as the development of a new biopharmaceutical to ultimately save lives.


Assuntos
Venenos de Abelha , Mordeduras e Picadas de Insetos , Abelhas , Humanos , Animais , Antivenenos/uso terapêutico , Mordeduras e Picadas de Insetos/tratamento farmacológico , Venenos de Abelha/análise , Venenos de Abelha/química , Meliteno/análise , Meliteno/química , Fosfolipases A2 , Antígenos
3.
J Toxicol Environ Health B Crit Rev, v. 27, n. 2, p. 73-90, jan. 2024
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-5250

RESUMO

Africanized bees have spread across the Americas since 1956 and consequently resulted in human and animal deaths attributed to massive attacks related to exposure from Argentina to the USA. In Brazil, more than 100,000 accidents were registered in the last 5 years with a total of 303 deaths. To treat such massive attacks, Brazilian researchers developed the first specific antivenom against Africanized honey bee sting exposure. This unique product, the first of its kind in the world, has been safely tested in 20 patients during a Phase 2 clinical trial. To develop the antivenom, a standardized process was undertaken to extract primary venom antigens from the Africanized bees for immunization of serum-producing horses. This process involved extracting, purifying, fractionating, characterizing, and identifying the venom (apitoxin) employing mass spectrometry to generate standardized antigen for hyperimmunization of horses using the major toxins (melittin and its isoforms and phospholipase A2). The current guide describes standardization of the entire production chain of venom antigens in compliance with good manufacturing practices (GMP) required by regulatory agencies. Emphasis is placed upon the welfare of bees and horses during this process, as well as the development of a new biopharmaceutical to ultimately save lives.

4.
Toxins (Basel) ; 15(11)2023 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-37999511

RESUMO

Snakebite envenoming is one of the most significantly neglected tropical diseases in the world. The lack of diagnosis/prognosis methods for snakebite is one of our motivations to develop innovative technological solutions for Brazilian health. The objective of this work was to evaluate the protein and metallic ion composition of Crotalus durissus terrificus, Bothrops jararaca, B. alternatus, B. jararacussu, B. moojeni, B. pauloensis, and Lachesis muta muta snake venoms. Brazilian snake venoms were subjected to the shotgun proteomic approach using mass spectrometry, and metal ion analysis was performed by atomic spectrometry. Shotgun proteomics has shown three abundant toxin classes (PLA2, serine proteases, and metalloproteinases) in all snake venoms, and metallic ions analysis has evidenced that the Cu2+ ion is present exclusively in the L. m. muta venom; Ca2+ and Mg2+ ions have shown a statistical difference between the species of Bothrops and Crotalus genus, whereas the Zn2+ ion presented a statistical difference among all species studied in this work. In addition, Mg2+ ions have shown 42 times more in the C. d. terrificus venom when compared to the average concentration in the other genera. Though metal ions are a minor fraction of snake venoms, several venom toxins depend on them. We believe that these non-protein fractions are capable of assisting in the development of unprecedented diagnostic devices for Brazilian snakebites.


Assuntos
Bothrops , Venenos de Crotalídeos , Mordeduras de Serpentes , Animais , Mordeduras de Serpentes/diagnóstico , Brasil , Proteômica , Venenos de Serpentes , Íons , Venenos de Crotalídeos/química
5.
Cell Mol Biol (Noisy-le-grand) ; 69(7): 19-23, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37715442

RESUMO

Simplexvirus humanalpha1 (HSV-1) affects approximately 67% of the world's population. Here, we sought to use the CRISPR / Cas9 system with the UL39 target, essential for virus replication. The sgRNA sequence was inserted into the plasmid (PX459-UL39). Vero cells were transfected with PX459-UL39, and inhibition of viral replication was assessed 24 and 48 hours later using plaque assays and fluorescence and qPCR. Fluorescence analyses revealed the presence of anti-HSV-1 CRISPR/Cas9 within Vero cells, and qPCR showed that the viral load decreased by> 95% of cells transfected with anti-HSV-1 CRISPR / Cas 9. Our data demonstrate the usefulness of the PX459-UL39 to inhibit HSV-1 infection.


Assuntos
Sistemas CRISPR-Cas , Herpesvirus Humano 1 , Animais , Chlorocebus aethiops , Sistemas CRISPR-Cas/genética , Herpesvirus Humano 1/genética , RNA Guia de Sistemas CRISPR-Cas , Células Vero , Ensaio de Placa Viral , Replicação Viral
6.
Cytotherapy ; 25(12): 1300-1306, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37318395

RESUMO

BACKGROUND AIMS: Amidst the success of cell therapy for the treatment of onco-hematological diseases, the first recently Food and Drug Administration-approved gene therapy product for patients with transfusion-dependent ß-thalassemia (TDT) indicates the feasibility of gene therapy as curative for genetic hematologic disorders. This work analyzed the current-world scenario of clinical trials involving gene therapy for ß-hemoglobinopathies. METHODS: Eighteen trials for patients with sickle cell disease (SCD) and 24 for patients with TDT were analyzed. RESULTS: Most are phase 1 and 2 trials, funded by the industry and are currently recruiting volunteers. Treatment strategies for both diseases are fetal hemoglobin induction (52.4%); addition of wild-type or therapeutic ß-globin gene (38.1%) and correction of mutations (9,5%). Gene editing (52.4%) and gene addition (40.5%) are the two most used techniques. The United States and France are the countries with the greatest number of clinical trials centers for SCD, with 83.1% and 4.2%, respectively. The United States (41.1%), China (26%) and Italy (6.8%) lead TDT trials centers. CONCLUSIONS: Geographic trial concentration indicates the high costs of this technology, logistical issues and social challenges that need to be overcome for gene therapy to reach low- and middle-income countries where SCD and TDT are prevalent and where they most impact the patient's health.


Assuntos
Anemia Falciforme , Hemoglobinopatias , Humanos , Hemoglobinopatias/genética , Hemoglobinopatias/terapia , Anemia Falciforme/genética , Anemia Falciforme/terapia , Terapia Baseada em Transplante de Células e Tecidos , China , Terapia Genética
7.
Rev. Bras. Saúde Mater. Infant. (Online) ; 22(4): 999-1006, Oct.-Dec. 2022. tab
Artigo em Inglês | LILACS | ID: biblio-1422678

RESUMO

Abstract Objectives: evaluate the relationship between family's food and nutrition insecurity (FNI) and the social network of malnourished children. Methods: cross-sectional study with 92 children, included in the economic class D-E. For the analysis of the children's social network, the mothers answered four simple questions. To investigate the FNI, the Brazilian Scale of Food Insecurity was used. The association between variables was analyzed by Poisson regression with robust analysis of variances. Results: 56.5% of the children had a weak social network (<10 individuals), and the prevalence of FNI was 72.8%. An inverse association was observed between children of the daily social network and FNI family (OR=0.94; CI95%=0.89-0.99], p=0.03). The number of individuals in the children's daily social network was negatively associated with the likelihood of FNI. The mother's educational level was also related to FNI (OR=2.20 [CI95%=1.11-4.34]; p=0.02), being the child up to 2.2 times more likely to be in FNI when the mother has less than four years of study. Conclusion: these results suggest that social network is associated with the FNI of malnourished children. Interventions designed to strengthen instrumental and other forms of support among small social networks can improve the health/nutrition of malnourished children with FNI.


Resumo Objetivos: avaliar a relação entre a insegurança alimentar e nutricional (IAN) da família e a rede social de crianças desnutridas. Métodos: estudo transversal com 92 crianças, inseridas na classe econômica D-E. Para a análise da rede social das crianças, as mães responderam quatro perguntas simples. Para investigar a IAN foi utilizada a Escala Brasileira de Insegurança Alimentar. A associação entre as variáveis foi analisada por regressão de Poisson com análise robusta das variâncias. Resultados: 56,5% das crianças apresentaram rede social fraca (<10 indivíduos), e a prevalência de IAN foi de 72,8%. Foi observada uma associação inversa entre rede social diária das crianças e IAN da família (RP=0,94, [IC95%=0,89-0,99]; p=0,03). O número de indivíduos na rede social diária das crianças se associou negativamente com a probabilidade de IAN. O nível de escolaridade materno também estava relacionado com a IAN (RP=2,20 [IC95%=1,11-4,34]; p=0,02), tendo a criança até 2,2 vezes mais probabilidade de estar em IAN quando a mãe apresenta menos de quatro anos de estudo. Conclusão: esses resultados sugerem que a rede social está associada à IAN de crianças desnutridas. Intervenções destinadas a fortalecer maneiras instrumentais e outras formas de apoio entre pequenas redes sociais podem melhorar a saúde/nutrição de crianças desnutridas com IAN.


Assuntos
Humanos , Criança , Transtornos da Nutrição Infantil/epidemiologia , Promoção da Saúde Alimentar e Nutricional , Indicadores Básicos de Saúde , Rede Social , Insegurança Alimentar , Fatores Socioeconômicos , Brasil , Assistência Integral à Saúde , Vulnerabilidade Social
8.
Cancers (Basel) ; 14(22)2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36428671

RESUMO

Chimeric Antigen Receptor (CAR)-T cell immunotherapy revolutionized cancer treatment and consists of the genetic modification of T lymphocytes with a CAR gene, aiming to increase their ability to recognize and kill antigen-specific tumor cells. The dynamics of CAR-T cell responses in patients present multiphasic kinetics with distribution, expansion, contraction, and persistence phases. The characteristics and duration of each phase depend on the tumor type, the infused product, and patient-specific characteristics. We present a mathematical model that describes the multiphasic CAR-T cell dynamics resulting from the interplay between CAR-T and tumor cells, considering patient and product heterogeneities. The CAR-T cell population is divided into functional (distributed and effector), memory, and exhausted CAR-T cell phenotypes. The model is able to describe the diversity of CAR-T cell dynamical behaviors in different patients and hematological cancers as well as their therapy outcomes. Our results indicate that the joint assessment of the area under the concentration-time curve in the first 28 days and the corresponding fraction of non-exhausted CAR-T cells may be considered a potential marker to classify therapy responses. Overall, the analysis of different CAR-T cell phenotypes can be a key aspect for a better understanding of the whole CAR-T cell dynamics.

9.
Toxins (Basel) ; 14(9)2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36136550

RESUMO

The clinical manifestations of Bothrops atrox envenoming involve local and systemic changes, among which edema requires substantial attention due to its ability to progress to compartmental syndromes and sometimes cause tissue loss and amputations. However, the impact of edema on the poisoned body's system has not been explored. Thus, the present study aimed to explore the systemic pathological and inflammatory events that are altered by intraplantar injection of B. atrox venom in a mouse model through hematologic, lipidic, and shotgun proteomics analysis. Plasma samples collected showed a greater abundance of proteins related to complement, coagulation, lipid system, platelet and neutrophil degranulation, and pathways related to cell death and ischemic tolerance. Interestingly, some proteins, in particular, Prdx2 (peroxiredoxin 2), Hba (hemoglobin subunit alpha), and F9 (Factor IX), increased according to the amount of venom injected. Our findings support that B. atrox venom activates multiple blood systems that are involved in thromboinflammation, an observation that may have implications for the pathophysiological progression of envenomations. Furthermore, we report for the first time a potential role of Prdx2, Hba, and F9 as potential markers of the severity of edema/inflammation in mice caused by B. atrox.


Assuntos
Bothrops , Venenos de Crotalídeos , Trombose , Animais , Venenos de Crotalídeos/toxicidade , Edema/induzido quimicamente , Fator IX , Subunidades de Hemoglobina , Inflamação , Lipídeos , Camundongos , Peroxirredoxinas , Plasma , Proteoma , Tromboinflamação
11.
Cancers (Basel) ; 14(11)2022 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35681646

RESUMO

In this systematic review, we foresee what could be the approved scenario in the next few years for CAR-T cell therapies directed against hematological and solid tumor malignancies. China and the USA are the leading regions in numbers of clinical studies involving CAR-T. Hematological antigens CD19 and BCMA are the most targeted, followed by mesothelin, GPC3, CEA, MUC1, HER2, and EGFR for solid tumors. Most CAR constructs are second-generation, although third and fourth generations are being largely explored. Moreover, the benefit of combining CAR-T treatment with immune checkpoint inhibitors and other drugs is also being assessed. Data regarding product formulation and administration, such as cell phenotype, transfection technique, and cell dosage, are scarce and could not be retrieved. Better tracking of trials' status and results on the ClinicalTrials.gov database should aid in a more concise and general view of the ongoing clinical trials involving CAR-T cell therapy.

12.
Cancers (Basel) ; 14(3)2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35158901

RESUMO

In this manuscript, we use an exactly solvable stochastic binary model for the regulation of gene expression to analyze the dynamics of response to a treatment aiming to modulate the number of transcripts of a master regulatory switching gene. The challenge is to combine multiple processes with different time scales to control the treatment response by a switching gene in an unavoidable noisy environment. To establish biologically relevant timescales for the parameters of the model, we select the RKIP gene and two non-specific drugs already known for changing RKIP levels in cancer cells. We demonstrate the usefulness of our method simulating three treatment scenarios aiming to reestablish RKIP gene expression dynamics toward a pre-cancerous state: (1) to increase the promoter's ON state duration; (2) to increase the mRNAs' synthesis rate; and (3) to increase both rates. We show that the pre-treatment kinetic rates of ON and OFF promoter switching speeds and mRNA synthesis and degradation will affect the heterogeneity and time for treatment response. Hence, we present a strategy for reaching increased average mRNA levels with diminished heterogeneity while reducing drug dosage by simultaneously targeting multiple kinetic rates that effectively represent the chemical processes underlying the regulation of gene expression. The decrease in heterogeneity of treatment response by a target gene helps to lower the chances of emergence of resistance. Our approach may be useful for inferring kinetic constants related to the expression of antimetastatic genes or oncogenes and for the design of multi-drug therapeutic strategies targeting the processes underpinning the expression of master regulatory genes.

13.
J Proteomics ; 253: 104464, 2022 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-34954398

RESUMO

Bothrops spp. is responsible for about 70% of snakebites in Brazil, causing a diverse and complex pathophysiological condition. Bothrops leucurus is the main species of medical relevance found in the Atlantic coast in the Brazilian Northeast region. The pathophysiological effects involved B. leucurus snakebite as well as the organism's reaction in response to this envenoming, it has not been explored yet. Thus, edema was induced in mice paw using 1.2, 2.5, and 5.0 µg of B. leucurus venom, the percentage of edema was measured 30 min after injection and the blood plasma was collected and analyzed by shotgun proteomic strategy. We identified 80 common plasma proteins with differential abundance among the experimental groups and we can understand the early aspects of this snake envenomation, regardless of the suggestive severity of an ophidian accident. The results showed B. leucurus venom triggers a thromboinflammation scenario where family's proteins of the Serpins, Apolipoproteins, Complement factors and Component subunits, Cathepsins, Kinases, Oxidoreductases, Proteases inhibitors, Proteases, Collagens, Growth factors are related to inflammation, complement and coagulation systems, modulators platelets and neutrophils, lipid and retinoid metabolism, oxidative stress and tissue repair. Our findings set precedents for future studies in the area of early diagnosis and/or treatment of snakebites. SIGNIFICANCE: The physiopathological effects that the snake venoms can cause have been investigated through classical and reductionist tools, which allowed, so far, the identification of action mechanisms of individual components associated with specific tissue damage. The currently incomplete limitations of this knowledge must be expanded through new approaches, such as proteomics, which may represent a big leap in understanding the venom-modulated pathological process. The exploration of the complete protein set that suffer modifications by the simultaneous action of multiple toxins, provides a map of the establishment of physiopathological phenotypes, which favors the identification of multiple toxin targets, that may or may not act in synergy, as well as favoring the discovery of biomarkers and therapeutic targets for manifestations that are not neutralized by the antivenom.


Assuntos
Bothrops , Venenos de Crotalídeos , Mordeduras de Serpentes , Trombose , Animais , Antivenenos/metabolismo , Bothrops/metabolismo , Venenos de Crotalídeos/toxicidade , Inflamação , Camundongos , Plasma/metabolismo , Proteoma , Proteômica , Venenos de Serpentes/toxicidade
14.
Oral Dis ; 28 Suppl 2: 2391-2399, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33853205

RESUMO

OBJECTIVE: To evaluate whether the coronavirus disease 2019 has increased anxiety, depression, and distress levels in head and neck cancer (HNC) patients undergoing radiotherapy (RT). METHODS: In this cross-sectional study, RT-HNC patients were surveyed using the Hospital Anxiety and Depression Scale (HADS) for anxiety and depression and the distress thermometer (DT) for distress. HADS scores were compared with data pre-COVID-19. Additionally, we evaluated the COVID-19 impact on daily routines, treatment, and cancer care through a questionnaire. RESULTS: Fifty patients were included. The HADS mean score and estimated rates were 4.34 (±4.06)/22% for anxiety and 5.08 (±4.82)/22% for depression; in comparison, our historical control had 4.04 (±3.59)/20% for anxiety (p = .79) and 4.03 (±3.62)/17% for depression (p = .49). Mean DT score was 3.68 (±2.77). Responders were aware of COVID-19, afraid of having medical complications, believed it was life-threatening, did not miss appointments, believed their treatment was not impacted, and felt safe at the hospital amid the pandemic. CONCLUSION: This study suggests that anxiety, depression, and distress levels found in RT-HNC patients did not increase during the pandemic. Patients were afraid of being infected by COVID-19; however, they complied with their cancer treatment.


Assuntos
COVID-19 , Neoplasias de Cabeça e Pescoço , Humanos , Estudos Transversais , Depressão/epidemiologia , Ansiedade , Inquéritos e Questionários , Neoplasias de Cabeça e Pescoço/complicações , Neoplasias de Cabeça e Pescoço/terapia , Estresse Psicológico
15.
Mol Ther Oncolytics ; 23: 239-253, 2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34761104

RESUMO

Several onco-virotherapy candidates have been developed and clinically evaluated for the treatment of cancer, and several are approved for clinical use. In this systematic review we explored the clinical impact of onco-virotherapy compared to other cancer therapies by analyzing factors such as trial design, patient background, therapy design, delivery strategies, and study outcomes. For this purpose, we retrieved clinical studies from three platforms: ClinicalTrials.gov, PubMed, and EMBASE. We found that most studies were performed in patients with advanced and metastatic tumors, using a broad range of genetically engineered vectors and mainly administered intratumorally. Therapeutic safety was the most frequently assessed outcome, while relatively few studies focused on immunological antitumor responses. Moreover, only 59 out of 896 clinical studies were randomized controlled trials reporting comparative data. This systemic review thus reveals the need of more, and better controlled, clinical studies to increase our understanding on the application of onco-virotherapy either as a single treatment or in combination with other cancer immunotherapies.

16.
Genes (Basel) ; 12(7)2021 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-34209776

RESUMO

Abnormal long non-coding RNAs (lncRNAs) expression has been documented to have oncogene or tumor suppressor functions in the development and progression of cancer, emerging as promising independent biomarkers for molecular cancer stratification and patients' prognosis. Examining the relationship between lncRNAs and the survival rates in malignancies creates new scenarios for precision medicine and targeted therapy. Breast cancer (BRCA) is a heterogeneous malignancy. Despite advances in its molecular classification, there are still gaps to explain in its multifaceted presentations and a substantial lack of biomarkers that can better predict patients' prognosis in response to different therapeutic strategies. Here, we performed a re-analysis of gene expression data generated using cDNA microarrays in a previous study of our group, aiming to identify differentially expressed lncRNAs (DELncRNAs) with a potential predictive value for response to treatment with taxanes in breast cancer patients. Results revealed 157 DELncRNAs (90 up- and 67 down-regulated). We validated these new biomarkers as having prognostic and predictive value for breast cancer using in silico analysis in public databases. Data from TCGA showed that compared to normal tissue, MIAT was up-regulated, while KCNQ1OT1, LOC100270804, and FLJ10038 were down-regulated in breast tumor tissues. KCNQ1OT1, LOC100270804, and FLJ10038 median levels were found to be significantly higher in the luminal subtype. The ROC plotter platform results showed that reduced expression of these three DElncRNAs was associated with breast cancer patients who did not respond to taxane treatment. Kaplan-Meier survival analysis revealed that a lower expression of the selected lncRNAs was significantly associated with worse relapse-free survival (RFS) in breast cancer patients. Further validation of the expression of these DELncRNAs might be helpful to better tailor breast cancer prognosis and treatment.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Resistencia a Medicamentos Antineoplásicos , RNA Longo não Codificante/genética , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Docetaxel/uso terapêutico , Feminino , Humanos , RNA Longo não Codificante/metabolismo , Análise de Sobrevida , Transcriptoma
17.
Cancers (Basel) ; 13(12)2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34208323

RESUMO

Immunotherapy has gained great momentum with chimeric antigen receptor T cell (CAR-T) therapy, in which patient's T lymphocytes are genetically manipulated to recognize tumor-specific antigens, increasing tumor elimination efficiency. In recent years, CAR-T cell immunotherapy for hematological malignancies achieved a great response rate in patients and is a very promising therapy for several other malignancies. Each new CAR design requires a preclinical proof-of-concept experiment using immunodeficient mouse models. The absence of a functional immune system in these mice makes them simple and suitable for use as mathematical models. In this work, we develop a three-population mathematical model to describe tumor response to CAR-T cell immunotherapy in immunodeficient mouse models, encompassing interactions between a non-solid tumor and CAR-T cells (effector and long-term memory). We account for several phenomena, such as tumor-induced immunosuppression, memory pool formation, and conversion of memory into effector CAR-T cells in the presence of new tumor cells. Individual donor and tumor specificities are considered uncertainties in the model parameters. Our model is able to reproduce several CAR-T cell immunotherapy scenarios, with different CAR receptors and tumor targets reported in the literature. We found that therapy effectiveness mostly depends on specific parameters such as the differentiation of effector to memory CAR-T cells, CAR-T cytotoxic capacity, tumor growth rate, and tumor-induced immunosuppression. In summary, our model can contribute to reducing and optimizing the number of in vivo experiments with in silico tests to select specific scenarios that could be tested in experimental research. Such an in silico laboratory is an easy-to-run open-source simulator, built on a Shiny R-based platform called CARTmath. It contains the results of this manuscript as examples and documentation. The developed model together with the CARTmath platform have potential use in assessing different CAR-T cell immunotherapy protocols and its associated efficacy, becoming an accessory for in silico trials.

18.
Crit Rev Immunol ; 41(1): 69-76, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33822525

RESUMO

Chimeric antigen receptor T (CAR-T) cells are proving their value in hematological cancers such as B cell acute lymphoid leukemia (B-ALL). This success is in great part due to the chosen target antigen, the lineage marker CD19, that is expressed by leukemia blasts and B lymphocytes, which are not crucial. For solid tumors, the challenge is greater because antigen expression is highly heterogeneous within the tumor and even an efficient CAR-T strategy would not kill all tumor cells. Also, many antigens are shared between solid tumors and healthy cells, causing off-target cell lysis and dangerous collateral damage. New antigen sources are emerging as targets, such as viruses, endogenous viruses, and immune checkpoint molecules. New technologies are in search of the ideal target, with antigen combinations the leading candidates.


Assuntos
Receptores de Antígenos Quiméricos , Antígenos CD19 , Antígenos de Neoplasias , Humanos , Imunoterapia Adotiva , Receptores de Antígenos de Linfócitos T , Receptores de Antígenos Quiméricos/genética , Linfócitos T
19.
J Toxicol Environ Health B Crit Rev ; 24(1): 30-50, 2021 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-33308037

RESUMO

One of the factors responsible for lack of reproducible findings may be attributed to the raw material used. To date, there are no apparent studies examining reproducibility using venoms for the development of new toxin-based drugs with respect to regulatory agencies' policies. For this reason, protocols were implemented to produce animal toxins with quality, traceability, and strict compliance with Good Manufacturing Practices. This required validation of the production chain from the arrival of the animal to the vivarium, followed by handling, housing, as well as compliance with respect to extraction, freeze-drying, and, finally, storage protocols, aimed at generating compounds to serve as candidate molecules applicable in clinical trials. Currently, to produce quality snake venoms to support reproductive studies, the Center for the Study of Venoms and Venomous Animals (CEVAP) from São Paulo State University (UNESP), São Paulo, Brazil has 449 microchipped snakes through rigid and standardized operating procedures for safety, health, and welfare of animals. Snakes were frequently subjected to vet clinical examination, anthelmintic, and antiparasitic treatment. Venom milk used to destroy prey was collected from each animal in individual plastic microtubes to avoid contamination and for traceability. In addition, venoms were submitted to microbiological, and biochemical toxicological analyses. It is noteworthy that investigators are responsible for caring, maintaining, and manipulating snakes and ensuring their health in captivity. This review aimed to contribute to the pharmaceutical industry the experimental experience and entire snake venom production chain required to generate quality products for therapeutic human consumption.


Assuntos
Produtos Biológicos/uso terapêutico , Indústria Farmacêutica/normas , Venenos de Serpentes/uso terapêutico , Animais , Produtos Biológicos/normas , Brasil , Desenvolvimento de Medicamentos/legislação & jurisprudência , Desenvolvimento de Medicamentos/normas , Humanos , Reprodutibilidade dos Testes , Serpentes
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...