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1.
Clin Chim Acta ; 564: 119945, 2025 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-39209245

RESUMEN

Acute myeloid leukemia (AML) is a common type of acute leukemia (AL), belonging to malignant tumors of the hematopoietic system with the characteristics of rapid disease development, control with extreme difficulties, easy recurrence, poor prognosis, and incidence rate increasing with age. The traditionally diagnostic standard of French American British (FAB), being based on the morphological examination with high human subjectivity, can no longer meet the demand of clinical diagnosis and treatment of AML. Requirements of objective accuracy and low-dose sample, have become the indispensable method for AML diagnosis and monitoring prognosis. Flow cytometry is a modern technology that can quickly and accurately detect the series, antigen distribution, differentiation stage of AML cells, minimal residual lesions after AML therapy, so as to provide the great significance in guiding clinical diagnosis, hierarchical treatment, and prognosis judgement. This article will systematically elaborate on the application of flow cytometry in the diagnosis and classification of AML, and the detection of minimal residual lesions, thereby providing reference significance for dynamic monitoring and prognostic observation of AML with different immune subtypes of FAB.


Asunto(s)
Citometría de Flujo , Leucemia Mieloide Aguda , Neoplasia Residual , Humanos , Leucemia Mieloide Aguda/diagnóstico , Neoplasia Residual/diagnóstico
2.
Biomaterials ; 313: 122798, 2025 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39244823

RESUMEN

Despite the development of antibody-drug conjugates, the fragment Fab-based drug conjugates offer some unique capabilities in terms of safety, clearance, penetration and others. Current methods for preparing Fab drug conjugates are limited by the availability and stability of Fab proteins, leaving reports on this rare. Here, we found that a single-chain scaffold of Fab enables stabilization of the paired structure and supports high-yield expression in bacteria cytoplasm. Furthermore, we conjugated anti-neoplastic agent SN38 to the C-terminus by sortase A ligation and generated a homogenous Fab conjugate with the drug-to-Fab ratio of 1. The resulting anti-HER2 Fab-SN38 conjugate demonstrated potent and antigen-dependent cell-killing ability with the aid of its special cathepsin-triggered cyclization-promoted release mechanism. In vivo, Fab-SN38 can prevent growths of HER2-positive tumors in athymic mice and be well tolerated to the treatment at 7 mg/kg per dose. Anti-tumor activity, high dose tolerance and penetration advantage observed in this study would merit Fab conjugate investigation in target chemotherapy.


Asunto(s)
Inmunoconjugados , Fragmentos Fab de Inmunoglobulinas , Ratones Desnudos , Receptor ErbB-2 , Animales , Receptor ErbB-2/metabolismo , Fragmentos Fab de Inmunoglobulinas/química , Humanos , Inmunoconjugados/química , Inmunoconjugados/farmacología , Línea Celular Tumoral , Femenino , Ratones , Antineoplásicos/farmacología , Antineoplásicos/química , Ratones Endogámicos BALB C , Sistemas de Liberación de Medicamentos
3.
Am J Med ; 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39265879

RESUMEN

While there has been a decline in the use of digoxin in patients with heart failure and atrial fibrillation, acute and chronic digoxin toxicity remains a significant clinical problem. Digoxin's narrow therapeutic window and nonspecific signs and symptoms of toxicity create clinical challenges and uncertainty around the diagnostic criteria of toxicity and responsive treatment choices for the bedside clinician. A systematic review of published literature on digoxin toxicity (34,587 publications over 6 decades, with 114 meeting inclusion criteria) was performed to develop 33 consensus statements on diagnostic and therapeutic approaches which were then evaluated through a modified Delphi process involving a panel of experts in cardiology, nursing, emergency medicine, and medical toxicology. The results demonstrate agreement about the need to consider time of ingestion and nature of the exposure (i.e. acute, acute-on-chronic, chronic) and the use of digoxin immune Fab for life-threatening exposure to decrease risk of death. While several areas of continued uncertainty were identified, this work offers formalized guidance that may help providers better manage this persistent clinical challenge.

4.
Clin Case Rep ; 12(9): e9376, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39219774

RESUMEN

Stone heart syndrome has a complex interaction with digoxin toxicity, where, theoretically, the administration of intravenous calcium can worsen a patient's condition. Research on this subject is conflicting, so it is imperative to approach it cautiously.

5.
Front Pharmacol ; 15: 1427325, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39263566

RESUMEN

Physiologically based pharmacokinetic (PBPK) modelling is an important tool to predict drug disposition in the body. Rabbits play a pivotal role as a highly valued small animal model, particularly in the field of ocular therapeutics, where they serve as a crucial link between preclinical research and clinical applications. In this context, we have developed PBPK models designed specifically for rabbits, with a focus on accurately predicting the pharmacokinetic profiles of protein therapeutics following intravenous administration. Our goal was to comprehend the influence of key physiological factors on systemic disposition of antibodies and their functional derivatives. For the development of the systemic PBPK models, rabbit physiological factors such as gene expression, body weight, neonatal fragment crystallizable receptor (FcRn) binding, target binding, target concentrations, and target turnover rate were meticulously considered. Additionally, key protein parameters, encompassing hydrodynamic radius, binding kinetic constants (KD, koff), internal degradation of the protein-target complex, and renal clearance, were represented in the models. Our final rabbit models demonstrated a robust correlation between predicted and observed serum concentration-time profiles after single intravenous administration in rabbits, covering IgG, Fab, F(ab)2, Fc, and Fc fusion proteins from various publications. These pharmacokinetic simulations offer a promising platform for translating preclinical findings to clinical settings. The presented rabbit intravenous PBPK models lay an important foundation for more specific applications of protein therapeutics in ocular drug development.

6.
Front Immunol ; 15: 1434463, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39281668

RESUMEN

Functionally bivalent non-covalent Fab dimers (Bi-Fabs) specific for the TCR/CD3 complex promote CD3 signaling on T cells. While comparing functional responses to stimulation with Bi-Fab, F(ab')2 or mAb specific for the same CD3 epitope, we observed fratricide requiring anti-CD3 bridging of adjacent T cells. Surprisingly, anti-CD3 Bi-Fab ranked first in fratricide potency, followed by anti-CD3 F(ab')2 and anti-CD3 mAb. Low resolution structural studies revealed anti-CD3 Bi-Fabs and F(ab')2 adopt similar global shapes with CD3-binding sites oriented outward. However, under molecular dynamic simulations, anti-CD3 Bi-Fabs crosslinked CD3 more rigidly than F(ab')2. Furthermore, molecular modelling of Bi-Fab and F(ab')2 binding to CD3 predicted crosslinking of T cell antigen receptors located in opposing plasma membrane domains, a feature fitting with T cell fratricide observed. Thus, increasing rigidity of Fab-CD3 crosslinking between opposing effector-target pairs may result in stronger T cell effector function. These findings could guide improving clinical performance of bi-specific anti-CD3 drugs.


Asunto(s)
Complejo CD3 , Fragmentos Fab de Inmunoglobulinas , Activación de Linfocitos , Linfocitos T , Complejo CD3/inmunología , Complejo CD3/metabolismo , Humanos , Linfocitos T/inmunología , Linfocitos T/metabolismo , Fragmentos Fab de Inmunoglobulinas/inmunología , Fragmentos Fab de Inmunoglobulinas/metabolismo , Fragmentos Fab de Inmunoglobulinas/química , Activación de Linfocitos/inmunología , Animales , Receptores de Antígenos de Linfocitos T/inmunología , Receptores de Antígenos de Linfocitos T/metabolismo , Unión Proteica , Simulación de Dinámica Molecular , Complejo Receptor-CD3 del Antígeno de Linfocito T/inmunología , Complejo Receptor-CD3 del Antígeno de Linfocito T/metabolismo , Ratones , Anticuerpos Monoclonales/inmunología , Transducción de Señal , Sitios de Unión
7.
Artículo en Inglés | MEDLINE | ID: mdl-39129293

RESUMEN

BACKGROUND: Angiogenesis is a process that many tumors depend on for growth, development, and metastasis. Vascular endothelial growth factor (VEGF) is one of the major players in tumor angiogenesis in several tumor types, including melanoma. VEGF inhibition is achieved by bevacizumab, a humanized monoclonal antibody that binds with high affinity to VEGF and prevents its function. In order to successfully enable in vivo VEGF expression imaging in a murine melanoma model, we previously labeled bevacizumab with [99mTc]Tc. We observed that this was feasible, but it had prolonged blood circulation and delayed tumor uptake. OBJECTIVE: The aim of this study was to develop a radiolabeled Fab bevacizumab fragment, [99mTc]Tc-HYNICFab( bevacizumab), for non-invasive in vivo VEGF expression molecular imaging. METHODS: Flow cytometry was used to examine VEGF presence in the murine melanoma cell line (B16-F10). Bevacizumab was digested with papain for six hours at 37°C to produce Fab(bevacizumab), which was then conjugated to NHS-HYNIC-Tfa for radiolabeling with [99mTc]Tc. Stability and binding affinity assays were also evaluated. Biodistribution and single photon emission computed tomography/computed tomography (SPECT/CT) were performed at 1, 3, and 6 h (n = 4) after injection of [99mTc]Tc-HYNIC-Fab(Bevacizumab) in normal and B16-F10 tumor-bearing C57Bl/6J mice. RESULTS: Using flow cytometry, it was shown that the B16-F10 murine melanoma cell line has intracellular VEGF expression. Papain incubation resulted in the complete digestion of bevacizumab with good purity and homogeneity. The radiolabeling yield of [99mTc]Tc-HYNIC-Fab(bevacizumab) was 85.00 ± 6.06%, with a specific activity of 291.87 ± 18.84 MBq/mg (n=3), showing in vitro stability. Binding assays demonstrated significant intracellular in vitro VEGF expression. Fast blood clearance and high kidney and tumor uptake were observed in biodistribution and SPECT/CT studies. CONCLUSIONS: We present the development and evaluation of [99mTc]Tc-HYNIC-Fab(bevacizumab), a novel molecular VEGF expression imaging agent that may be used for precision medicine in melanoma and potentially in other VEGF-expressing tumors.

8.
Bioresour Bioprocess ; 11(1): 82, 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39177850

RESUMEN

Bispecific antibodies (bsAbs) hold promises for enhanced therapeutic potential surpassing that of their parental monoclonal antibodies. However, bsAbs pose great challenges in their manufacturing, and one of the common reasons is their susceptibility to aggregation. Building on previous studies demonstrating the functionality and potential manufacturability of Fab-scFv format bsAb, this investigation delved into the impact of environmental factors-such as pH, buffer types, ionic strength, protein concentrations, and temperatures-on its stability and the reversal of its self-associated aggregates. Mildly acidic, low-salt conditions were found optimal, ensuring bsAb stability for 30 days even at elevated temperature of 40 °C. Furthermore, these conditions facilitated the reversal of its self-associated aggregates to monomers during the initial 7-day incubation period. Our findings underscore the robustness and resilience of Fab-scFv format bsAb, further confirming its potential manufacturability despite its current absence as commercial products.

9.
Biomedicines ; 12(8)2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39200362

RESUMEN

Idiopathic normal-pressure hydrocephalus (iNPH) is a clinic-radiological neurological syndrome presenting with cognitive deficits, gait disturbances and urinary incontinence. It often coexists with Alzheimer's disease (AD). Due to the reversible nature of iNPH when promptly treated, a lot of studies have focused on possible biomarkers, among which are cerebrospinal fluid (CSF) biomarkers. The aim of the present study was to determine the rate of beta-amyloid pathology and AD co-pathology by measuring AD CSF biomarkers, namely, amyloid beta with 42 and 40 amino acids (Aß42), the Aß42/Aß40 ratio, total Tau protein (t-Tau) and phosphorylated Tau protein at threonine 181 (p-Tau), in a cohort of iNPH patients, as well as to investigate the possible associations among CSF biomarkers and iNPH neuropsychological profiles. Fifty-three patients with iNPH were included in the present study. CSF Aß42, Aß40, t-Tau and p-Tau were measured in duplicate with double-sandwich ELISA assays. The neuropsychological evaluation consisted of the Mini-Mental State Examination, Frontal Assessment Battery, Five-Word Test and CLOX drawing tests 1 and 2. After statistical analysis, we found that amyloid pathology and AD co-pathology are rather common in iNPH patients and that higher values of t-Tau and p-Tau CSF levels, as well as the existence of the AD CSF profile, are associated with more severe memory impairment in the study patients. In conclusion, our study has confirmed that amyloid pathology and AD-co-pathology are rather common in iNPH patients and that CSF markers of AD pathology and t-Tau are associated with a worse memory decline in these patients.

10.
Protein Pept Lett ; 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39161140

RESUMEN

BACKGROUND: Protein A resins have been widely used for product capture during mAb, bispecific antibody (bsAb), and Fc-fusion protein purification. While Protein A ligands mainly bind the Fc region, many of them can also bind the VH3 domain. During mAb/bsAb purification, certain truncated byproducts may contain the same Fc region as the product but fewer numbers of the VH3 domain. In such a scenario, VH3-binding Protein A resins provide a potential means for byproduct separation based on the difference in VH3-binding valency. As the ligands of different VH3-binding Protein A resins are derived from distinct domains of the native Protein A, it would be interesting to know whether they possess comparable capabilities for separating species with the same Fc region but different numbers of VH3 domain. OBJECTIVE: This study aims to explore the potential of different VH3-binding Protein A resins for separating antibody species with the same Fc region but different numbers of VH3 domain. METHODS: The VH3 Fab was released from a VH3-containing mAb by papain digestion. Post digestion, the released VH3 Fab was purified sequentially using CaptureSelect CH1-XL and MabSelect SuRe affinity chromatography. The purified VH3 Fab was used as the load material to assess the dynamic binding capacity (DBC) of five VH3-binding Protein A resins (i.e., Amshpere A3, Jetted A50, MabCapture C, MabSelect and MabSelect PrismA). The potential of VH3-binding Protein A resins for separating species having the same Fc region but different numbers of VH3 domain was evaluated using an artificial mixture composed of the product and a truncated byproduct, which contained one and zero VH3 domain, respectively (both species contained the same Fc region). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was used to monitor Fab purification and separation of species containing the same Fc region but different numbers of VH3 domain. RESULTS: When loaded with an isolated VH3 Fab, different VH3-binding Protein A resins showed varied DBCs. Nevertheless, when these Protein A resins were used to separate a truncated byproduct, which contained the Fc region only without any VH3 domain, from the product, which included one VH3 domain in addition to the Fc region, they showed comparable capabilities for separating these two species. CONCLUSION: Although different VH3-binding Protein A resins showed varied DBCs towards a VH3 Fab, they exhibited comparable capabilities for separating species with the same Fc region but different numbers of VH3 domain.

11.
Front Immunol ; 15: 1429600, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39185413

RESUMEN

Introduction: N-glycosylation is a post-translational modification that is highly important for the development of monoclonal antibodies (mAbs), as it regulates their biological activity, particularly in terms of immune effector functions. While typically added at the Fc level, approximately 15-25% of circulating antibodies exhibit glycosylation in the Fab domains as well. To the best of our knowledge, cetuximab (Erbitux®) is the only therapeutic antibody presenting Fab glycosylation approved world-wide targeting the epidermal growth factor receptor for the treatment of metastatic-colorectal and head and neck cancers. Additionally, it can trigger antibody-dependent cell cytotoxicity (ADCC), a response that typically is influenced by N-glycosylation at Fc level. However, the role of Fab glycosylation in cetuximab remains poorly understood. Hence, this study aims to investigate the structural role of Fab glycosylation on the conformational behavior of cetuximab. Methods: The study was performed in silico via accelerated molecular dynamics simulations. The commercial cetuximab was compared to its form without Fab glycosylation and structural descriptors were evaluated to establish conformational differences. Results: The results clearly show a correlation between the Fab glycosylation and structural descriptors that may modulate the conformational freedom of the antibody, potentially affecting Fc effector functions, and suggesting a negative role of Fab glycosylation on the interaction with FcγRIIIa. Conclusion: Fab glycosylation of cetuximab is the most critical challenge for biosimilar development, but the differences highlighted in this work with respect to its aglycosylated form can improve the knowledge and represent also a great opportunity to develop novel strategies of biotherapeutics.


Asunto(s)
Cetuximab , Fragmentos Fab de Inmunoglobulinas , Simulación de Dinámica Molecular , Cetuximab/inmunología , Glicosilación , Humanos , Fragmentos Fab de Inmunoglobulinas/inmunología , Fragmentos Fab de Inmunoglobulinas/química , Fragmentos Fab de Inmunoglobulinas/metabolismo , Citotoxicidad Celular Dependiente de Anticuerpos/inmunología , Simulación por Computador , Antineoplásicos Inmunológicos/inmunología , Antineoplásicos Inmunológicos/farmacología , Conformación Proteica , Receptores ErbB/inmunología , Receptores ErbB/metabolismo
12.
Pathogens ; 13(8)2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39204225

RESUMEN

Enterobacterales resistant to extended-spectrum cephalosporins (ESC) are a marker of the antimicrobial resistance (AMR) burden. They are infecting humans, but the intestinal microbiota can also be transiently colonized without developing symptoms. Healthy carriage can promote silent dissemination of resistant bacteria, and data on this colonization are often lacking. Between 2021 and 2023, a sampling of healthy Tunisian people was carried out. Fecal samples (n = 256) were plated on selective agar, and all collected isolates were characterized by phenotypic (antibiograms) and genomic (whole-genome sequencing) methods. A total of 26 (26/256, 10.2%) isolates were collected, including 24 Escherichia coli and 2 Klebsiella pneumoniae. In total, 17 isolates (15 E. coli and 2 K. pneumoniae) presented an ESBL phenotype conferred by the blaCTX-M-15 gene, and 9 E. coli isolates presented an AmpC phenotype conferred by the blaDHA-1 gene. K. pneumoniae belonged to ST1564 and ST313, while E. coli belonged to diverse STs including the pandemic ST131 clone. Clonally related ST349 E. coli isolates carrying the blaDHA-1 gene were found in nine individuals. In parallel, four blaCTX-M-15 -positive E. coli isolates carried this ESC-resistance gene on an epidemic plasmid IncF/F-:A-:B53 previously identified in Tunisian pigeons and fish. These findings highlight the spread of genetically diverse ESC-resistant Enterobacterales as well as an epidemic plasmid in Tunisia, emphasizing the need for antimicrobial stewardship to limit the transmission of these resistances in the Tunisian population.

13.
MAbs ; 16(1): 2394230, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39192463

RESUMEN

We previously described an in vitro single-chain fragment (scFv) library platform originally designed to generate antibodies with excellent developability properties. The platform design was based on the use of clinical antibodies as scaffolds into which replicated natural complementarity-determining regions purged of sequence liabilities were inserted, and the use of phage and yeast display to carry out antibody selection. In addition to being developable, antibodies generated using our platform were extremely diverse, with most campaigns yielding sub-nanomolar binders. Here, we describe a platform advancement that incorporates Fab phage display followed by single-chain antibody-binding fragment Fab (scFab) yeast display. The scFab single-gene format provides balanced expression of light and heavy chains, with enhanced conversion to IgG, thereby combining the advantages of scFvs and Fabs. A meticulously engineered, quality-controlled Fab phage library was created using design principles similar to those used to create the scFv library. A diverse panel of binding scFabs, with high conversion efficiency to IgG, was isolated against two targets. This study highlights the compatibility of phage and yeast display with a Fab semi-synthetic library design, offering an efficient approach to generate drug-like antibodies directly, facilitating their conversion to potential therapeutic candidates.


Asunto(s)
Afinidad de Anticuerpos , Fragmentos Fab de Inmunoglobulinas , Biblioteca de Péptidos , Anticuerpos de Cadena Única , Fragmentos Fab de Inmunoglobulinas/genética , Fragmentos Fab de Inmunoglobulinas/inmunología , Fragmentos Fab de Inmunoglobulinas/química , Humanos , Anticuerpos de Cadena Única/genética , Anticuerpos de Cadena Única/inmunología , Anticuerpos de Cadena Única/química , Afinidad de Anticuerpos/inmunología , Técnicas de Visualización de Superficie Celular/métodos , Inmunoglobulina G/genética , Inmunoglobulina G/inmunología , Inmunoglobulina G/química
14.
Int J Biol Macromol ; 275(Pt 2): 133730, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38986973

RESUMEN

The binding of functional groups to antibodies is crucial for disease treatment, diagnosis, and basic scientific research. Traditionally, antibody modifications have focused on the Fc region to maintain antigen-antibody binding activity. However, such modifications may impact critical antibody functions, including immune cell surface receptor activation, cytokine release, and other immune responses. In recent years, modifications targeting the antigen-binding fragment (Fab) region have garnered increasing attention. Precise modifications of the Fab region not only maximize the retention of antigen-antibody binding capacity but also enhance numerous physicochemical properties of antibodies. This paper reviews the chemical, biological, biochemical, and computer-assisted methods for modifying the Fab region of antibodies, discussing their advantages, limitations, recent advances, and future trends.


Asunto(s)
Fragmentos Fab de Inmunoglobulinas , Ingeniería de Proteínas , Fragmentos Fab de Inmunoglobulinas/química , Fragmentos Fab de Inmunoglobulinas/inmunología , Humanos , Ingeniería de Proteínas/métodos , Animales , Anticuerpos/química , Anticuerpos/inmunología
15.
J Rural Med ; 19(3): 186-191, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38975040

RESUMEN

Objective: Identifying the peripheral biomarkers related to the prevention or modification of unhealthy mental conditions in older adults is extremely beneficial. This study aimed to evaluate the serum levels of soluble triggering receptor expressed on myeloid cells 2 (sTREM2), a soluble form of an innate immune receptor expressed on microglia, in older adults living in a rural community, and their association with cognitive function. Materials and Methods: This survey was conducted between November 2016 and September 2017 in Kurokawa-cho, Imari, Saga Prefecture, Japan, among people aged ≥65 years. Blood samples were collected from the participants for serum sTREM2 level analysis using a peptide enzyme immunoassay. The participants underwent cognitive function assessments, including the Mini-Mental State Examination, Clinical Dementia Rating, and Frontal Assessment Battery. Therefore, we examined the association between serum sTREM2 levels and cognitive function. Results: Of the 95 participants, 25 were men and 70 were women with a mean age 78.24 ± 3.85 years and 77.96 ± 5.52 years, respectively. Serum sTREM2 levels were negatively associated with Frontal Assessment Battery scores, even after adjusting for age, sex, years of education, and serum high-sensitivity C-reactive protein levels. Conclusion: Serum sTREM2 levels may be associated with frontal lobe function in adults aged ≥65 years.

16.
Bioanalysis ; 16(15): 791-800, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39041663

RESUMEN

Background: Antisense oligonucleotides (ASOs) have been conjugated to various moieties, such as peptides, antibodies or Fab regions of antibodies, to enhance their delivery to target tissues. The quantitation of free ASO (ASO payload) is critical to characterize its pharmacokinetics/pharmacodynamics (PK/PD) properties and biodistribution after delivery of the peptide/antibody/Fab ASO conjugates.Results: We developed a hybridization-based LC-MS/MS methodology for quantification of free ASO in tissues in the presence of Fab-ASO and ASO with linker (ASO-linker).Conclusion: The developed method was applied to measure accurately the free ASO concentrations in liver and gastrocnemius in mice that were dosed with Fab-ASO. This methodology has also been applied to free ASO bioanalysis for other antibody-ASO and Fab-ASO conjugates in various tissues and plasma/serum samples.


[Box: see text].


Asunto(s)
Oligonucleótidos Antisentido , Espectrometría de Masas en Tándem , Espectrometría de Masas en Tándem/métodos , Animales , Oligonucleótidos Antisentido/farmacocinética , Oligonucleótidos Antisentido/química , Ratones , Cromatografía Liquida/métodos , Distribución Tisular , Hígado/metabolismo , Anticuerpos/inmunología , Cromatografía Líquida con Espectrometría de Masas
17.
Int J Mol Sci ; 25(12)2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38928061

RESUMEN

We review the importance of monocytic differentiation and differentiation induction in non-APL (acute promyelocytic leukemia) variants of acute myeloid leukemia (AML), a malignancy characterized by proliferation of immature myeloid cells. Even though the cellular differentiation block is a fundamental characteristic, the AML cells can show limited signs of differentiation. According to the French-American-British (FAB-M4/M5 subset) and the World Health Organization (WHO) 2016 classifications, monocytic differentiation is characterized by morphological signs and the expression of specific molecular markers involved in cellular communication and adhesion. Furthermore, monocytic FAB-M4/M5 patients are heterogeneous with regards to cytogenetic and molecular genetic abnormalities, and monocytic differentiation does not have any major prognostic impact for these patients when receiving conventional intensive cytotoxic therapy. In contrast, FAB-M4/M5 patients have decreased susceptibility to the Bcl-2 inhibitor venetoclax, and this seems to be due to common molecular characteristics involving mitochondrial regulation of the cellular metabolism and survival, including decreased dependency on Bcl-2 compared to other AML patients. Thus, the susceptibility to Bcl-2 inhibition does not only depend on general resistance/susceptibility mechanisms known from conventional AML therapy but also specific mechanisms involving the molecular target itself or the molecular context of the target. AML cell differentiation status is also associated with susceptibility to other targeted therapies (e.g., CDK2/4/6 and bromodomain inhibition), and differentiation induction seems to be a part of the antileukemic effect for several targeted anti-AML therapies. Differentiation-associated molecular mechanisms may thus become important in the future implementation of targeted therapies in human AML.


Asunto(s)
Diferenciación Celular , Resistencia a Antineoplásicos , Leucemia Mieloide Aguda , Mitocondrias , Monocitos , Humanos , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patología , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/genética , Mitocondrias/metabolismo , Monocitos/metabolismo , Monocitos/patología , Resistencia a Antineoplásicos/genética , Terapia Molecular Dirigida , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico
18.
Anal Chim Acta ; 1315: 342760, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38879206

RESUMEN

Mycotoxins are commonly found in food materials and severely threaten human health. Antibodies play a key role as a part of immunological techniques in detecting mycotoxins. Therefore, highly specific antibodies and detection techniques against mycotoxins need to be developed for advancements in medical research. In this study, we presented a novel strategy for quickly screening highly specific antigen-binding fragment (Fab) antibodies based on yeast surface display (YSD) and detecting small-molecule compounds based on a YSD biosensor. We constructed a yeast surface display Deoxynivalenol (DON)-Fab library with 105 cfu/mL with a galactose-inducible bidirectional promoter. By conducting efficient magnetic-activated cell sorting and fluorescence-activated cell sorting (MACS/FACS), four kinds of DON-selective yeasts were screened. As Fab@YSD C4# showed high sensitivity, we used it to build a one-pot Fab@YSD chemiluminescence biosensor with DON-BSA@Biotin and Streptavidin-alkaline phosphatase (SA-ALP). This method showed a low operational threshold (LOD = 0.166 pg/mL) and a high population range (linear range = 0.001-132.111 ng/mL) within 40 min, which facilitated the detection of DON with high specificity and better recovery in real samples (wheat, corn, flour, and cornmeal). Our results suggested that the Fab@YSD chemiluminescence biosensor is an inexpensive, reproducible, user-friendly, and sensitive method for detecting DON and may be used to quickly detect other small-molecule contaminants in food items.


Asunto(s)
Técnicas Biosensibles , Tricotecenos , Tricotecenos/análisis , Técnicas Biosensibles/métodos , Saccharomyces cerevisiae , Contaminación de Alimentos/análisis , Fragmentos Fab de Inmunoglobulinas/química , Fragmentos Fab de Inmunoglobulinas/inmunología , Límite de Detección , Triticum/química , Triticum/microbiología , Zea mays/química , Zea mays/microbiología , Harina/análisis
19.
Int J Mol Sci ; 25(12)2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38928395

RESUMEN

Antibodies that can selectively remove rogue proteins in the brain are an obvious choice to treat neurodegenerative disorders (NDs), but after decades of efforts, only two antibodies to treat Alzheimer's disease are approved, dozens are in the testing phase, and one was withdrawn, and the other halted, likely due to efficacy issues. However, these outcomes should have been evident since these antibodies cannot enter the brain sufficiently due to the blood-brain barrier (BBB) protectant. However, all products can be rejuvenated by binding them with transferrin, preferably as smaller fragments. This model can be tested quickly and at a low cost and should be applied to bapineuzumab, solanezumab, crenezumab, gantenerumab, aducanumab, lecanemab, donanemab, cinpanemab, and gantenerumab, and their fragments. This paper demonstrates that conjugating with transferrin does not alter the binding to brain proteins such as amyloid-ß (Aß) and α-synuclein. We also present a selection of conjugate designs that will allow cleavage upon entering the brain to prevent their exocytosis while keeping the fragments connected to enable optimal binding to proteins. The identified products can be readily tested and returned to patients with the lowest regulatory cost and delays. These engineered antibodies can be manufactured by recombinant engineering, preferably by mRNA technology, as a more affordable solution to meet the dire need to treat neurodegenerative disorders effectively.


Asunto(s)
Enfermedades Neurodegenerativas , Ingeniería de Proteínas , Humanos , Enfermedades Neurodegenerativas/tratamiento farmacológico , Enfermedades Neurodegenerativas/metabolismo , Ingeniería de Proteínas/métodos , Transferrina/metabolismo , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/efectos de los fármacos , Péptidos beta-Amiloides/metabolismo , Péptidos beta-Amiloides/inmunología , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales/farmacología , Animales , alfa-Sinucleína/inmunología , alfa-Sinucleína/metabolismo , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Encéfalo/metabolismo , Encéfalo/patología
20.
Metabolomics ; 20(3): 63, 2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38796596

RESUMEN

INTRODUCTION: Fighter pilots must support the effects of many stressors, including physical and psychological exertion, circadian disturbance, jet lag, and environmental stress. Despite the rigorous selection of military pilots, those factors predispose to failures in physiological compensatory mechanisms and metabolic flexibility. OBJECTIVES: We compared through NMR-based metabolomics the metabolic profile of Brazilian F5 fighter pilots with different flight experiences vs. the control group of non-pilots. We hypothesized that combat pilots have metabolic flexibility associated with combat flight time. METHODS: We evaluated for the first time 34 Brazilian fighter pilots from Santa Cruz Air Base (Rio de Janeiro, RJ) allocated into three groups: pilots with lower total accumulated flight experience < 1,100 h (PC1, n = 7); pilots with higher total accumulated flight experience ≥ 1,100 h (PC2, n = 6); military non-pilots (CONT, n = 21). Data collection included anthropometric measurements, total blood count, lipidogram, markers of oxidative stress, and serum NMR-based metabolomics. RESULTS: In comparison with controls (p < 0.05), pilots exhibited decreased levels of white blood cells (-13%), neutrophils (-15%), lymphocytes (-20%), alfa-glucose (-13%), lactate (-26%), glutamine (-11%), histidine (-20%), and tyrosine (-11%), but higher isobutyrate (+ 10%) concentrations. Significant correlations were found between lactate vs. amino acids in CONT (r = 0.55-0.68, p < 0.001), and vs. glutamine in PC2 (r = 0.94, p = 0.01). CONCLUSION: Fighter pilots with lower experience showed a dysregulation in immune-metabolic function in comparison with controls, which seemed to be counteracted by the accumulation of flight hours. Those findings might have implications for the health preservation and operational training of fighter pilots.


Asunto(s)
Personal Militar , Pilotos , Humanos , Brasil , Masculino , Adulto , Metabolómica/métodos , Metaboloma/fisiología , Estrés Oxidativo/fisiología , Espectroscopía de Resonancia Magnética/métodos , Medicina Aeroespacial
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