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1.
Annu Rev Biochem ; 88: 433-459, 2019 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-30917003

RESUMEN

Antibodies are immunoglobulins that play essential roles in immune systems. All antibodies are glycoproteins that carry at least one or more conserved N-linked oligosaccharides (N-glycans) at the Fc domain. Many studies have demonstrated that both the presence and fine structures of the attached glycans can exert a profound impact on the biological functions and therapeutic efficacy of antibodies. However, antibodies usually exist as mixtures of heterogeneous glycoforms that are difficult to separate in pure glycoforms. Recent progress in glycoengineering has provided useful methods that enable production of glycan-defined and site-selectively modified antibodies for functional studies and for improved therapeutic efficacy. This review highlights major approaches in glycoengineering of antibodies with a focus on recent advances in three areas: glycoengineering through glycan biosynthetic pathway manipulation, glycoengineering through in vitro chemoenzymatic glycan remodeling, and glycoengineering of antibodies for site-specific antibody-drug conjugation.


Asunto(s)
Anticuerpos/metabolismo , Ingeniería de Proteínas/métodos , Animales , Anticuerpos/química , Glicoproteínas , Glicosilación , Humanos
2.
Cell ; 167(3): 843-857.e14, 2016 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-27720451

RESUMEN

Glucagon and thyroid hormone (T3) exhibit therapeutic potential for metabolic disease but also exhibit undesired effects. We achieved synergistic effects of these two hormones and mitigation of their adverse effects by engineering chemical conjugates enabling delivery of both activities within one precisely targeted molecule. Coordinated glucagon and T3 actions synergize to correct hyperlipidemia, steatohepatitis, atherosclerosis, glucose intolerance, and obesity in metabolically compromised mice. We demonstrate that each hormonal constituent mutually enriches cellular processes in hepatocytes and adipocytes via enhanced hepatic cholesterol metabolism and white fat browning. Synchronized signaling driven by glucagon and T3 reciprocally minimizes the inherent harmful effects of each hormone. Liver-directed T3 action offsets the diabetogenic liability of glucagon, and glucagon-mediated delivery spares the cardiovascular system from adverse T3 action. Our findings support the therapeutic utility of integrating these hormones into a single molecular entity that offers unique potential for treatment of obesity, type 2 diabetes, and cardiovascular disease.


Asunto(s)
Glucagón/uso terapéutico , Enfermedades Metabólicas/tratamiento farmacológico , Triyodotironina/efectos de los fármacos , Animales , Aterosclerosis/tratamiento farmacológico , Peso Corporal/efectos de los fármacos , Huesos/efectos de los fármacos , Ingeniería Química/métodos , Colesterol/metabolismo , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Modelos Animales de Enfermedad , Combinación de Medicamentos , Sistemas de Liberación de Medicamentos , Sinergismo Farmacológico , Glucagón/efectos adversos , Glucagón/química , Glucagón/farmacología , Hiperglucemia/tratamiento farmacológico , Hígado/efectos de los fármacos , Hígado/metabolismo , Ratones , Terapia Molecular Dirigida , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Obesidad/tratamiento farmacológico , Triyodotironina/efectos adversos , Triyodotironina/química , Triyodotironina/farmacología
3.
Trends Immunol ; 44(10): 826-844, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37704549

RESUMEN

Klebsiella pneumoniae is among the most common antibiotic-resistant pathogens causing nosocomial infections. Additionally, it is a leading cause of neonatal sepsis and childhood mortality across the globe. Despite its clinical importance, we are only beginning to understand how the mammalian adaptive immune system responds to this pathogen. Further, many studies investigating potential K. pneumoniae vaccine candidates or alternative therapies have been launched in recent years. Here, we review the current state of knowledge on the adaptive immune response to K. pneumoniae infections and progress towards developing vaccines and other therapies to combat these infections.


Asunto(s)
Infecciones por Klebsiella , Vacunas , Animales , Niño , Humanos , Recién Nacido , Antibacterianos/farmacología , Infecciones por Klebsiella/tratamiento farmacológico , Infecciones por Klebsiella/prevención & control , Klebsiella pneumoniae , Mamíferos
4.
FASEB J ; 38(13): e23759, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38949635

RESUMEN

The epidermal growth factor receptor (EGFR) is an important target for cancer therapies. Many head and neck cancer (HNC) cells have been reported to overexpress EGFR; therefore, anti-EGFR therapies have been attempted in patients with HNC. However, its clinical efficacy is limited owing to the development of drug resistance. In this study, we developed an EGFR-targeting immunotoxin consisting of a clinically proven anti-EGFR IgG (cetuximab; CTX) and a toxin fragment (LR-LO10) derived from Pseudomonas exotoxin A (PE) using a novel site-specific conjugation technology (peptide-directed photo-crosslinking reaction), as an alternative option. The immunotoxin (CTX-LR-LO10) showed specific binding to EGFR and properties of a typical IgG, such as stability, interactions with receptors of immune cells, and pharmacokinetics, and inhibited protein synthesis via modification of elongation factor-2. Treatment of EGFR-positive HNC cells with the immunotoxin resulted in apoptotic cell death and the inhibition of cell migration and invasion. The efficacy of CTX-LR-LO10 was evaluated in xenograft mouse models, and the immunotoxin exhibited much stronger tumor suppression than CTX or LR-LO10. Transcriptome analyses revealed that the immunotoxins elicited immune responses and altered the expression of genes related to its mechanisms of action. These results support the notion that CTX-LR-LO10 may serve as a new therapeutic agent targeting EGFR-positive cancers.


Asunto(s)
ADP Ribosa Transferasas , Receptores ErbB , Exotoxinas , Neoplasias de Cabeza y Cuello , Inmunoglobulina G , Inmunotoxinas , Exotoxina A de Pseudomonas aeruginosa , Factores de Virulencia , Humanos , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/metabolismo , Receptores ErbB/inmunología , Animales , Inmunotoxinas/farmacología , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/inmunología , Neoplasias de Cabeza y Cuello/metabolismo , Ratones , Inmunoglobulina G/farmacología , Línea Celular Tumoral , Exotoxinas/farmacología , Ensayos Antitumor por Modelo de Xenoinjerto , Cetuximab/farmacología , Ratones Desnudos , Toxinas Bacterianas , Apoptosis/efectos de los fármacos , Ratones Endogámicos BALB C , Femenino , Movimiento Celular/efectos de los fármacos , Antineoplásicos/farmacología
5.
CA Cancer J Clin ; 68(2): 116-132, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29194581

RESUMEN

Hodgkin lymphoma (HL) is a unique hematopoietic neoplasm characterized by cancerous Reed-Sternberg cells in an inflammatory background. Patients are commonly diagnosed with HL in their 20s and 30s, and they present with supradiaphragmatic lymphadenopathy, often with systemic B symptoms. Even in advanced-stage disease, HL is highly curable with combination chemotherapy, radiation, or combined-modality treatment. Although the same doxorubicin, bleomycin, vinblastine, and dacarbazine chemotherapeutic regimen has been the mainstay of therapy over the last 30 years, risk-adapted approaches have helped de-escalate therapy in low-risk patients while intensifying treatment for higher risk patients. Even patients who are not cured with initial therapy can often be salvaged with alternate chemotherapy combinations, the novel antibody-drug conjugate brentuximab, or high-dose autologous or allogeneic hematopoietic stem cell transplantation. The programmed death-1 inhibitors nivolumab and pembrolizumab have both demonstrated high response rates and durable remissions in patients with relapsed/refractory HL. Alternate donor sources and reduced-intensity conditioning have made allogeneic hematopoietic stem cell transplantation a viable option for more patients. Future research will look to integrate novel strategies into earlier lines of therapy to improve the HL cure rate and minimize long-term treatment toxicities. CA Cancer J Clin 2018;68:116-132. © 2017 American Cancer Society.


Asunto(s)
Enfermedad de Hodgkin/diagnóstico , Enfermedad de Hodgkin/terapia , Protocolos de Quimioterapia Combinada Antineoplásica , Biomarcadores de Tumor/sangre , Terapia Combinada , Diagnóstico Diferencial , Diagnóstico por Imagen , Trasplante de Células Madre Hematopoyéticas , Enfermedad de Hodgkin/mortalidad , Enfermedad de Hodgkin/patología , Humanos , Estadificación de Neoplasias , Pronóstico , Factores de Riesgo , Análisis de Supervivencia , Acondicionamiento Pretrasplante/tendencias
6.
Mol Ther ; 32(6): 1672-1686, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38549377

RESUMEN

Stem cell gene therapy and hematopoietic stem cell transplantation (SCT) require conditioning to ablate the recipient's hematopoietic stem cells (HSCs) and create a niche for gene-corrected/donor HSCs. Conventional conditioning agents are non-specific, leading to off-target toxicities and resulting in significant morbidity and mortality. We developed tissue-specific anti-human CD45 antibody-drug conjugates (ADCs), using rat IgG2b anti-human CD45 antibody clones YTH24.5 and YTH54.12, conjugated to cytotoxic pyrrolobenzodiazepine (PBD) dimer payloads with cleavable (SG3249) or non-cleavable (SG3376) linkers. In vitro, these ADCs internalized to lysosomes for drug release, resulting in potent and specific killing of human CD45+ cells. In humanized NSG mice, the ADCs completely ablated human HSCs without toxicity to non-hematopoietic tissues, enabling successful engraftment of gene-modified autologous and allogeneic human HSCs. The ADCs also delayed leukemia onset and improved survival in CD45+ tumor models. These data provide proof of concept that conditioning with anti-human CD45-PBD ADCs allows engraftment of donor/gene-corrected HSCs with minimal toxicity to non-hematopoietic tissues. Our anti-CD45-PBDs or similar agents could potentially shift the paradigm in transplantation medicine that intensive chemo/radiotherapy is required for HSC engraftment after gene therapy and allogeneic SCT. Targeted conditioning both improve the safety and minimize late effects of these procedures, which would greatly increase their applicability.


Asunto(s)
Benzodiazepinas , Terapia Genética , Trasplante de Células Madre Hematopoyéticas , Inmunoconjugados , Antígenos Comunes de Leucocito , Animales , Humanos , Ratones , Inmunoconjugados/farmacología , Antígenos Comunes de Leucocito/metabolismo , Terapia Genética/métodos , Trasplante de Células Madre Hematopoyéticas/métodos , Benzodiazepinas/farmacología , Benzodiazepinas/química , Células Madre Hematopoyéticas/metabolismo , Células Madre Hematopoyéticas/efectos de los fármacos , Ratas , Acondicionamiento Pretrasplante/métodos , Modelos Animales de Enfermedad , Anticuerpos Monoclonales/farmacología , Pirroles
7.
Proc Natl Acad Sci U S A ; 119(22): e2122595119, 2022 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-35609195

RESUMEN

Despite recent advances in cancer therapy, hard-to-reach, unidentified tumors remain a significant clinical challenge. A promising approach is to treat locatable and accessible tumors locally and stimulate antitumor immunity in situ to exert systemic effects against distant tumors. We hypothesize that a carrier of immunotherapeutics can play a critical role in activating antitumor immunity as an immunoadjuvant and a local retainer of drug combinations. Here, we develop a polyethyleneimine-lithocholic acid conjugate (2E'), which forms a hydrophobic core and cationic surface to codeliver hydrophobic small molecules and anionic nucleic acids and activates antigen-presenting cells via the intrinsic activities of 2E' components. 2E' delivers paclitaxel and small-interfering RNA (siRNA) targeting PD-L1 (or cyclic dinucleotide, [CDN]) to induce the immunogenic death of tumor cells and maintain the immunoactive tumor microenvironment, and further activates dendritic cells and macrophages, leveraging the activities of loaded drugs. A single local administration of 2E' or its combination with paclitaxel and PD-L1­targeting siRNA or CDN induces strong antitumor immunity, resulting in immediate regression of large established tumors, tumor-free survival, an abscopal effect on distant tumors, and resistance to rechallenge and metastasis in multiple models of murine tumors, including CT26 colon carcinoma, B16F10 melanoma, and 4T1 breast cancer. This study supports the finding that local administration of immunotherapeutics, when accompanied by the rationally designed carrier, can effectively protect the host from distant and recurrent diseases.


Asunto(s)
Neoplasias , Ácidos Nucleicos , Línea Celular Tumoral , Humanos , Inmunoterapia , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Ácidos Nucleicos/uso terapéutico , Paclitaxel/uso terapéutico , Polímeros/uso terapéutico
8.
BMC Biol ; 22(1): 66, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38486229

RESUMEN

BACKGROUND: Antibody drug conjugates (ADCs) constitute a promising class of targeted anti-tumor therapeutics that harness the selectivity of monoclonal antibodies with the potency of cytotoxic drugs. ADC development is best suited to initially screening antibody candidates for desired properties that potentiate target cell cytotoxicity. However, validating and producing an optimally designed ADC requires expertise and resources not readily available to certain laboratories. RESULTS: In this study, we propose a novel approach to help streamline the identification of potential ADC candidates by utilizing a granzyme B (GrB)-based antibody fusion protein (AFP) for preliminary screening. GrB is a non-immunogenic serine protease expressed by immune effector cells such as CD8 + T cells that induces apoptotic activity and can be leveraged for targeted cell killing. CONCLUSIONS: Our innovative model allows critical antibody parameters (including target cell binding, internalization, and cytotoxic potential) to be more reliably evaluated in vitro through the creation of an ADC surrogate. Successful incorporation of this AFP could also significantly expand and enhance ADC development pre-clinically, ultimately leading to the accelerated translation of ADC therapies for patients.


Asunto(s)
Antineoplásicos , Inmunoconjugados , Humanos , Inmunoconjugados/farmacología , Inmunoconjugados/química , Granzimas , alfa-Fetoproteínas , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Anticuerpos Monoclonales , Línea Celular Tumoral
9.
Nano Lett ; 24(3): 950-957, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38198622

RESUMEN

Sonodynamic therapy (SDT) was hampered by the sonosensitizers with low bioavailability, tumor accumulation, and therapeutic efficiency. In situ responsive sonosensitizer self-assembly strategy may provide a promising route for cancer sonotheranositics. Herein, an intelligent sonotheranostic peptide-purpurin conjugate (P18-P) is developed that can self-assemble into supramolecular structures via self-aggregation triggered by rich enzyme cathepsin B (CTSB). After intravenous injection, the versatile probe could achieve deep tissue penetration because of the penetration sequence of P18-P. More importantly, CTSB-triggered self-assembly strongly prolonged retention time, amplified photoacoustic imaging signal for sensitive CTSB detection, and boosted reactive oxygen species for advanced SDT, evoking specific CTSB responsive sonotheranostics. This peptide-purpurin conjugate may serve as an efficient sonotheranostic platform for the early diagnosis of CTSB activity and effective cancer therapy.


Asunto(s)
Nanopartículas , Neoplasias , Terapia por Ultrasonido , Humanos , Catepsina B , Terapia por Ultrasonido/métodos , Neoplasias/tratamiento farmacológico , Péptidos/uso terapéutico , Especies Reactivas de Oxígeno , Línea Celular Tumoral , Nanopartículas/química
10.
J Infect Dis ; 230(1): e189-e198, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39052729

RESUMEN

BACKGROUND: Streptococcus pneumoniae serotype 3 remains a problem globally. Malawi introduced 13-valent pneumococcal conjugate vaccine (PCV13) in 2011, but there has been no direct protection against serotype 3 carriage. We explored whether vaccine escape by serotype 3 is due to clonal expansion of a lineage with a competitive advantage. METHODS: The distribution of serotype 3 Global Pneumococcal Sequence Clusters (GPSCs) and sequence types (STs) globally was assessed using sequences from the Global Pneumococcal Sequencing Project. Whole-genome sequences of 135 serotype 3 carriage isolates from Blantyre, Malawi (2015-2019) were analyzed. Comparative analysis of the capsule locus, entire genomes, antimicrobial resistance, and phylogenetic reconstructions were undertaken. Opsonophagocytosis was evaluated using serum samples from vaccinated adults and children. RESULTS: Serotype 3 GPSC10-ST700 isolates were most prominent in Malawi. Compared with the prototypical serotype 3 capsular polysaccharide locus sequence, 6 genes are absent, with retention of capsule polysaccharide biosynthesis. This lineage is characterized by increased antimicrobial resistance and lower susceptibility to opsonophagocytic killing. CONCLUSIONS: A serotype 3 variant in Malawi has genotypic and phenotypic characteristics that could enhance vaccine escape and clonal expansion after post-PCV13 introduction. Genomic surveillance among high-burden populations is essential to improve the effectiveness of next-generation pneumococcal vaccines.


Asunto(s)
Cápsulas Bacterianas , Filogenia , Infecciones Neumocócicas , Vacunas Neumococicas , Serogrupo , Streptococcus pneumoniae , Humanos , Vacunas Neumococicas/inmunología , Vacunas Neumococicas/administración & dosificación , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/inmunología , Streptococcus pneumoniae/clasificación , Infecciones Neumocócicas/prevención & control , Infecciones Neumocócicas/microbiología , Infecciones Neumocócicas/inmunología , Cápsulas Bacterianas/inmunología , Cápsulas Bacterianas/genética , Malaui , Adulto , Secuenciación Completa del Genoma , Preescolar , Niño , Vacunas Conjugadas/inmunología , Masculino , Genoma Bacteriano , Femenino , Adulto Joven , Lactante , Genotipo , Portador Sano/microbiología
11.
J Infect Dis ; 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38498565

RESUMEN

BACKGROUND: In 2022-2023, 15- and 20-valent pneumococcal conjugate vaccines (PCV15/PCV20) were recommended for infants. We aimed to estimate the incidence of outpatient visits and antibiotic prescriptions in U.S. children (≤17 years) from 2016-2019 for acute otitis media, pneumonia, and sinusitis associated with PCV15- and PCV20-additional (non-PCV13) serotypes to quantify PCV15/20 potential impacts. METHODS: We estimated the incidence of PCV15/20-additional serotype-attributable visits and antibiotic prescriptions as the product of all-cause incidence rates, derived from national healthcare surveys and MarketScan databases, and PCV15/20-additional serotype-attributable fractions. We estimated serotype-specific attributable fractions using modified vaccine-probe approaches incorporating incidence changes post-PCV13 and ratios of PCV13 versus PCV15/20 serotype frequencies, estimated through meta-analyses. RESULTS: Per 1000 children annually, PCV15-additional serotypes accounted for an estimated 2.7 (95% confidence interval 1.8-3.9) visits and 2.4 (1.6-3.4) antibiotic prescriptions. PCV20-additional serotypes resulted in 15.0 (11.2-20.4) visits and 13.2 (9.9-18.0) antibiotic prescriptions annually per 1,000 children. PCV15/20-additional serotypes account for 0.4% (0.2-0.6%) and 2.1% (1.5-3.0%) of pediatric outpatient antibiotic use. CONCLUSIONS: Compared with PCV15-additional serotypes, PCV20-additional serotypes account for >5 times the burden of visits and antibiotic prescriptions. Higher-valency PCVs, especially PCV20, may contribute to preventing pediatric pneumococcal respiratory infections and antibiotic use.

12.
J Infect Dis ; 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39101606

RESUMEN

BACKGROUND: Pneumococcal carriage is associated with increased acquisition and duration of SARS-CoV-2 infection among adults. While pneumococcal conjugate vaccines (PCVs) prevent carriage of vaccine-serotype pneumococci, their potential impact on COVID-19 related outcomes remains poorly understood in populations with prevalent immunity against SARS-CoV-2. METHODS: We undertook a retrospective cohort study of adults aged ≥65 years in the Kaiser Permanente Southern California (KPSC) healthcare system who had received ≥2 COVID-19 vaccine doses, comparing risk of SARS-CoV-2 infection between 1 January, 2021 and 31 December, 2022 among recipients and non-recipients of PCV13. We estimated adjusted hazard ratios via Cox proportional hazards models, employing multiple strategies to mitigate bias from differential test-seeking behavior. RESULTS: The adjusted hazard ratio (aHR) of confirmed SARS-CoV-2 infection comparing PCV13 recipients to non-recipients was 0.92 (95% confidence interval: 0.90-0.95), corresponding to prevention of 3.9 (2.6-5.3) infections per 100 person-years. Following receipt of 2, 3, and ≥4 COVID-19 vaccine doses, aHRs were 0.85 (0.81-0.89), 0.94 (0.90-0.97), and 0.99 (0.93-1.04), respectively. The aHR for persons who had not received COVID-19 vaccination in the preceding 6 months was 0.90 (0.86-0.93), versus 0.94 (0.91-0.98) within 6 months after receipt of any dose. Similarly, the aHR was 0.92 (0.89-0.94) for persons without history of documented SARS-CoV-2 infection, versus 1.00 (0.90-1.12) for persons with documented prior infection. CONCLUSIONS: Among older adults who had received ≥2 COVID-19 vaccine doses, PCV13 was associated with modest protection against SARS-CoV-2 infection. Protective effects of PCV13 were greater among individuals expected to have weaker immune protection against SARS-CoV-2 infection.

13.
J Infect Dis ; 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38462672

RESUMEN

BACKGROUND: In addition to preventing pneumococcal disease, emerging evidence indicates that pneumococcal conjugate vaccines (PCVs) might indirectly reduce viral respiratory tract infections (RTI) by affecting pneumococcal-viral interactions. METHODS: We performed a systematic review of interventional and observational studies published during 2000-2022 on vaccine efficacy/adjusted effectiveness (VE) and overall effect of PCV7, PCV9, PCV10, or PCV13 against viral RTI. RESULTS: Sixteen of 1671 records identified were included. Thirteen publications described effects of PCVs against viral RTIs in children. VE against influenza ranged between 41-86% (n=4), except for the 2010-2011 influenza season. In a randomized controlled trial, PCV9 displayed efficacy against any viral RTI, human seasonal coronavirus, parainfluenza, and human metapneumovirus. Data in adults were limited (n=3). PCV13 VE ranged between 4-25% against viral lower RTI, 32-35% against COVID-19 outcomes, 24-51% against human seasonal coronavirus, and 13-36% against influenza A lower RTI, with some 95%CI spanning zero. No protection was found against adenovirus or rhinovirus in children or adults. CONCLUSIONS: PCVs were associated with protection against some viral RTI, with the strongest evidence for influenza in children. Limited evidence for adults was generally consistent with pediatric data. Restricting public health evaluations to confirmed pneumococcal outcomes may underestimate the full impact of PCVs.

14.
J Infect Dis ; 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38502711

RESUMEN

BACKGROUND: Pneumococcal conjugate vaccines (PCVs) provide strong direct protection in children, while limited data are available on their indirect effect on mortality among older age groups. This multi-country study aimed to assess the population-level impact of pediatric PCVs on all-cause pneumonia mortality among ≥5 years of age, and invasive pneumococcal disease (IPD) cases in Chile. METHODS: Demographic and mortality data from Argentina, Brazil, Chile, Colombia, and Mexico were collected considering the ≥ 5-year-old population, from 2000-2019, with 1,795,789 deaths due to all-cause pneumonia. IPD cases in Chile were also evaluated. Time series models were employed to evaluate changes in all-cause pneumonia deaths during the post-vaccination period, with other causes of death used as synthetic controls for unrelated temporal trends. RESULTS: No significant change in death rates due to all-cause pneumonia was detected following PCV introduction among most age groups and countries. The proportion of IPD cases caused by vaccine serotypes decreased from 29% (2012) to 6% (2022) among ≥65 years in Chile. DISCUSSION: While an effect of PCV against pneumonia deaths (a broad clinical definition that may not be specific enough to measure indirect effects) was not detected, evidence of indirect PCV impact was observed among vaccine-type-specific IPD cases.

15.
Q Rev Biophys ; 55: e5, 2022 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-35570679

RESUMEN

Lipid-DNA conjugates have emerged as highly useful tools to modify the cell membranes. These conjugates generally consist of a lipid anchor for membrane modification and a functional DNA nanostructure for membrane analysis or regulation. There are several unique properties of these lipid-DNA conjugates, especially including their programmability, fast and efficient membrane insertion, and precise sequence-specific assembly. These unique properties have enabled a broad range of biophysical applications on live cell membranes. In this review, we will mainly focus on recent tremendous progress, especially during the past three years, in regulating the biophysical features of these lipid-DNA conjugates and their key applications in studying cell membrane biophysics. Some insights into the current challenges and future directions of this interdisciplinary field have also been provided.


Asunto(s)
ADN , Nanoestructuras , Biofisica , Membrana Celular , ADN/química , Lípidos , Nanoestructuras/química
16.
Med Res Rev ; 2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38704826

RESUMEN

The development of peptide drugs has made tremendous progress in the past few decades because of the advancements in modification chemistry and analytical technologies. The novel-designed peptide drugs have been modified through various biochemical methods with improved diagnostic, therapeutic, and drug-delivery strategies. Researchers found it a helping hand to overcome the inherent limitations of peptides and bring continued advancements in their applications. Furthermore, the emergence of peptide-drug conjugates (PDCs)-utilizes target-oriented peptide moieties as a vehicle for cytotoxic payloads via conjugation with cleavable chemical agents, resulting in the key foundation of the new era of targeted peptide drugs. This review summarizes the various classifications of peptide drugs, suitable chemical modification strategies to improve the ADME (adsorption, distribution, metabolism, and excretion) features of peptide drugs, and recent (2015-early 2024) progress/achievements in peptide-based drug delivery systems as well as their fruitful implication in preclinical and clinical studies. Furthermore, we also summarized the brief description of other types of PDCs, including peptide-MOF conjugates and peptide-UCNP conjugates. The principal aim is to provide scattered and diversified knowledge in one place and to help researchers understand the pinching knots in the science of PDC development and progress toward a bright future of novel peptide drugs.

17.
Am J Physiol Cell Physiol ; 327(2): C362-C371, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38912730

RESUMEN

This review provides a rationale for using the Food and Drug Administration (FDA)-approved antibody-drug conjugates (ADCs) for implementing as therapy in recurrent refractory germ cell tumors similar to their position in the treatment of other types of chemoresistant solid tumors. Germ cell tumors (GCTs) originate from germ cells; they most frequently develop in ovaries or in the testes, while being the most common type of malignancy in young men. GCTs are very sensitive to cisplatin-based chemotherapy, but therapeutic resistance occurs in a considerable number of cases, which is associated with disease recurrence and poor patient prognosis. ADCs are a novel type of targeted antitumor agents that combine tumor antigen-specific monoclonal antibodies with chemically linked chemotherapeutic drugs (payload) exerting a cytotoxic effect. Several FDA-approved ADCs use as targeting moieties the antigens that are also detected in the GCTs, offering a benefit of this type of targeted therapy even for patients with relapsed/refractory testicular GCTs (rrTGCT) unresponsive to standard chemotherapy.


Asunto(s)
Resistencia a Antineoplásicos , Inmunoconjugados , Recurrencia Local de Neoplasia , Neoplasias de Células Germinales y Embrionarias , Humanos , Neoplasias de Células Germinales y Embrionarias/tratamiento farmacológico , Neoplasias de Células Germinales y Embrionarias/inmunología , Neoplasias de Células Germinales y Embrionarias/patología , Inmunoconjugados/uso terapéutico , Inmunoconjugados/farmacología , Resistencia a Antineoplásicos/efectos de los fármacos , Recurrencia Local de Neoplasia/tratamiento farmacológico , Neoplasias Testiculares/tratamiento farmacológico , Neoplasias Testiculares/patología , Masculino , Antineoplásicos/uso terapéutico , Animales , Antineoplásicos Inmunológicos/uso terapéutico , Antineoplásicos Inmunológicos/farmacología
18.
Infect Immun ; 92(3): e0042723, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38391207

RESUMEN

To address the problem of increased antimicrobial resistance, we developed a glycoconjugate vaccine comprised of O-polysaccharides (OPS) of the four most prevalent serotypes of Klebsiella pneumoniae (KP) linked to recombinant flagellin types A and B (rFlaA and rFlaB) of Pseudomonas aeruginosa (PA). Flagellin is the major subunit of the flagellar filament. Flagella A and B, essential virulence factors for PA, are glycosylated with different glycans. We previously reported that while both rFlaA and rFlaB were highly immunogenic, only the rFlaB antisera reduced PA motility and protected mice from lethal PA infection in a mouse model of thermal injury. Since recombinant flagellin is not glycosylated, we examined the possibility that the glycan on native FlaA (nFlaA) might be critical to functional immune responses. We compared the ability of nFlaA to that of native, deglycosylated FlaA (dnFlaA) to induce functionally active antisera. O glycan was removed from nFlaA with trifluoromethanesulfonic acid. Despite the similar high-titered anti-FlaA antibody levels elicited by nFlaA, rFlaA, and dnFlaA, only the nFlaA antisera inhibited PA motility and protected mice following lethal intraperitoneal bacterial challenge. Both the protective efficacy and carrier protein function of nFlaA were retained when conjugated to KP O1 OPS. We conclude that unlike the case with FlaB O glycan, the FlaA glycan is an important epitope for the induction of functionally active anti-FlaA antibodies.


Asunto(s)
Flagelina , Pseudomonas aeruginosa , Ratones , Animales , Flagelina/metabolismo , Anticuerpos , Klebsiella pneumoniae , Polisacáridos , Flagelos/metabolismo , Sueros Inmunes
19.
Clin Infect Dis ; 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39140767

RESUMEN

BACKGROUND: In mid-2018, the Australian childhood 13-valent pneumococcal conjugate vaccine schedule changed from 3+0 to 2+1, moving the third dose to 12 months of age, to address increasing breakthrough cases of invasive pneumococcal disease (IPD), predominantly in children aged >12 months. This study assessed the impact of this change using national IPD surveillance data. METHODS: Pre- and postschedule change 3-dose 13-valent pneumococcal conjugate vaccine breakthrough cases were compared by age group, serotype, and clinical syndrome. Annual rates of breakthrough cases were calculated (per 100 000) using respective birth cohort sizes and 3-dose vaccine coverage. Using time-series modelling, observed IPD rates in children aged <12 years were compared to that expected if the 3+0 schedule were continued. FINDINGS: Over 2012-2022, rate of 3-dose breakthrough cases in children aged >12 months was 2.8 per 100 000 (n = 557; 11 birth cohorts). Serotype 3 replaced 19A as predominant breakthrough serotype (respectively, 24% and 65% in 2013 to 60% and 20% in 2022) followed by 19F. In breakthrough cases, the most frequent clinical phenotype was bacteremic pneumonia (69%), with meningitis accounting for 3%-4%. In cohorts eligible for 2+1 versus 3+0 schedules, rate of breakthrough cases was lower for all vaccine serotypes, except type 3 (incidence rate ratio, 0.50 [95% confidence interval, .28-.84] and 1.12 [0.71-1.76], respectively). Observed compared to expected IPD was 51.7% lower (95% confidence interval, -60.9 to -40.7%) for vaccine serotypes, but the change for nonvaccine types was not significant 12% (-9.6 to 39.7). INTERPRETATIONS: The 2+1 schedule is likely superior to 3+0 for overall IPD control, a finding that may be worth consideration for other countries considering or using 3+0 PCV schedules.

20.
Lab Invest ; 104(7): 102073, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38718982

RESUMEN

The glycans form a unique complex on the surface of cancer cells and play a pivotal role in tumor progression, impacting proliferation, invasion, and metastasis. TRA-1-60 is a glycan that was identified as a critical marker for the establishment of fully reprogrammed inducible pluripotent stem cells. Its expression has been detected in multiple cancer tissues, including embryonal carcinoma, prostate cancer, and pancreatic cancer, but the biological and pathological characterization of TRA-1-60-expressing tumor cells remains unclear within various types of malignancies. Here, we report the biological characteristics of TRA-1-60-expressing gastric cancer cells, especially those with its cell surface expression, and the therapeutic significance of targeting TRA-1-60. The cells with cell membrane expression of TRA-1-60 were mainly observed in the invasive area of patient gastric cancer tissues and correlated with advanced stages of the disease based on histopathological and clinicopathological analyses. In vitro analysis using a scirrhous gastric adenocarcinoma line, HSC-58, which highly expresses TRA-1-60 on its plasma membrane, revealed increased stress-resistant mechanisms, supported by the upregulation of glutathione synthetase and NCF-1 (p47phox) via lipid-ROS regulatory pathways, as detected by RNA-seq analysis followed by oxidative stress gene profiling. Our in vivo therapeutic study using the TRA-1-60-targeting antibody-drug conjugate, namely, Bstrongomab-conjugated monomethyl auristatin E, showed robust efficacy in a mouse model of peritoneal carcinomatosis induced by intraperitoneal xenograft of HSC-58, by markedly reducing massive tumor ascites. Thus, targeting the specific cell surface glycan, TRA-1-60, shows a significant therapeutic impact in advanced-stage gastric cancers.


Asunto(s)
Adenocarcinoma , Polisacáridos , Neoplasias Gástricas , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patología , Humanos , Animales , Línea Celular Tumoral , Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Ratones , Polisacáridos/metabolismo , Masculino , Femenino , Ratones Desnudos
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