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1.
Nat Commun ; 15(1): 4271, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38769289

RESUMEN

T Cell Receptor (TCR) antigen binding underlies a key mechanism of the adaptive immune response yet the vast diversity of TCRs and the complexity of protein interactions limits our ability to build useful low dimensional representations of TCRs. To address the current limitations in TCR analysis we develop a capacity-controlled disentangling variational autoencoder trained using a dataset of approximately 100 million TCR sequences, that we name TCR-VALID. We design TCR-VALID such that the model representations are low-dimensional, continuous, disentangled, and sufficiently informative to provide high-quality TCR sequence de novo generation. We thoroughly quantify these properties of the representations, providing a framework for future protein representation learning in low dimensions. The continuity of TCR-VALID representations allows fast and accurate TCR clustering and is benchmarked against other state-of-the-art TCR clustering tools and pre-trained language models.


Asunto(s)
Receptores de Antígenos de Linfocitos T , Receptores de Antígenos de Linfocitos T/inmunología , Receptores de Antígenos de Linfocitos T/metabolismo , Receptores de Antígenos de Linfocitos T/genética , Humanos , Aprendizaje Profundo , Algoritmos , Análisis por Conglomerados , Biología Computacional/métodos , Secuencia de Aminoácidos
2.
J Immunother Cancer ; 12(3)2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38519055

RESUMEN

BACKGROUND: Patients with relapsed/refractory B-cell non-Hodgkin lymphoma (R/R B-NHL) have a significant need for effective treatment options. Odronextamab is an Fc-silenced, human, CD20×CD3 bispecific antibody that targets CD20-expressing cells via T-cell-mediated cytotoxicity independent of T-cell/major histocompatibility complex interaction. Phase I results in patients with R/R B-NHL demonstrated that odronextamab monotherapy could achieve deep and durable responses with a generally manageable safety profile (ELM-1; NCT02290951). As part of a biomarker analysis of the same study, we investigated potential biomarkers and mechanisms of resistance to odronextamab. METHODS: Patients with R/R B-NHL enrolled in ELM-1 received one time per week doses of intravenous odronextamab for 4×21 day cycles, then doses every 2 weeks thereafter. Patient tumor biopsies were obtained at baseline, on-treatment, and at progression. Immune cell markers were analyzed by immunohistochemistry, flow cytometry, single-cell RNA sequencing, and whole genome sequencing. RESULTS: Baseline tumor biopsies showed that almost all patients had high proportions of B cells that expressed the CD20 target antigen, whereas expression of other B-cell surface antigens (CD19, CD22, CD79b) was more variable. Responses to odronextamab in patients with diffuse large B-cell lymphoma were not related to the relative level of baseline CD20 expression, cell of origin, or high-risk molecular subtype. A potential link was observed between greater tumor programmed cell death-ligand 1 expression and increased likelihood of response to odronextamab. Similarly, a trend was observed between clinical response and increased levels of CD8 T cells and regulatory T cells at baseline. We also identified an on-treatment pharmacodynamic shift in intratumoral immune cell subsets. Finally, loss of CD20 expression through inactivating gene mutations was identified as a potential mechanism of resistance in patients who were treated with odronextamab until progression, as highlighted in two detailed patient cases reported here. CONCLUSIONS: This biomarker analysis expands on clinical findings of odronextamab in patients with R/R B-NHL, providing verification of the suitability of CD20 as a therapeutic target, as well as evidence for potential mechanisms of action and resistance.


Asunto(s)
Anticuerpos Biespecíficos , Antineoplásicos , Linfoma de Células B Grandes Difuso , Humanos , Antineoplásicos/uso terapéutico , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Linfoma de Células B Grandes Difuso/genética , Resultado del Tratamiento , Anticuerpos Biespecíficos/farmacología , Anticuerpos Biespecíficos/uso terapéutico , Antígenos CD20
3.
Front Big Data ; 6: 1258051, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37915357
4.
Dis Model Mech ; 16(10)2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-37718909

RESUMEN

Sezary syndrome (SS) is a rare, aggressive leukemic variant of cutaneous T-cell lymphoma (CTCL) that lacks adequate therapeutic options and representative small-animal models. Here, we demonstrate that IL-15 is a critical CTCL growth factor. Importantly, an immunodeficient knock-in mouse model genetically engineered to express human IL-15 uniquely supported the growth of SS patient samples relative to conventional immunodeficient mouse strains. SS patient-derived xenograft (PDX) models recapacitated key pathological features of the human disease, including skin infiltration and spread of leukemic cells to the periphery, and maintained the dependence on human IL-15 upon serial in vivo passaging. Detailed molecular characterization of the engrafted cells by single-cell transcriptomic analysis revealed congruent neoplastic gene expression signatures but distinct clonal engraftment patterns. Overall, we document an important dependence of Sezary cell survival and proliferation on IL-15 signaling and the utility of immunodeficient humanized IL-15 mice as hosts for SS - and potentially other T and NK cell-derived hematologic malignancies - PDX model generation. Furthermore, these studies advocate the thorough molecular understanding of the resultant PDX models to maximize their translational impact.


Asunto(s)
Linfoma Cutáneo de Células T , Síndrome de Sézary , Neoplasias Cutáneas , Humanos , Animales , Ratones , Neoplasias Cutáneas/metabolismo , Interleucina-15 , Linfoma Cutáneo de Células T/patología , Síndrome de Sézary/metabolismo , Síndrome de Sézary/patología , Linfocitos/metabolismo , Microambiente Tumoral
5.
Nat Med ; 29(6): 1389-1399, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37322116

RESUMEN

Despite no apparent defects in T cell priming and recruitment to tumors, a large subset of T cell rich tumors fail to respond to immune checkpoint blockade (ICB). We leveraged a neoadjuvant anti-PD-1 trial in patients with hepatocellular carcinoma (HCC), as well as additional samples collected from patients treated off-label, to explore correlates of response to ICB within T cell-rich tumors. We show that ICB response correlated with the clonal expansion of intratumoral CXCL13+CH25H+IL-21+PD-1+CD4+ T helper cells ("CXCL13+ TH") and Granzyme K+ PD-1+ effector-like CD8+ T cells, whereas terminally exhausted CD39hiTOXhiPD-1hiCD8+ T cells dominated in nonresponders. CD4+ and CD8+ T cell clones that expanded post-treatment were found in pretreatment biopsies. Notably, PD-1+TCF-1+ (Progenitor-exhausted) CD8+ T cells shared clones mainly with effector-like cells in responders or terminally exhausted cells in nonresponders, suggesting that local CD8+ T cell differentiation occurs upon ICB. We found that these Progenitor CD8+ T cells interact with CXCL13+ TH within cellular triads around dendritic cells enriched in maturation and regulatory molecules, or "mregDC". These results suggest that discrete intratumoral niches that include mregDC and CXCL13+ TH control the differentiation of tumor-specific Progenitor exhasuted CD8+ T cells following ICB.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamiento farmacológico , Linfocitos T CD8-positivos , Neoplasias Hepáticas/patología , Receptor de Muerte Celular Programada 1 , Linfocitos T Colaboradores-Inductores , Diferenciación Celular , Células Dendríticas/patología
6.
Sci Rep ; 13(1): 8452, 2023 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-37231180

RESUMEN

Identifying epitopes that T cells respond to is critical for understanding T cell-mediated immunity. Traditional multimer and other single cell assays often require large blood volumes and/or expensive HLA-specific reagents and provide limited phenotypic and functional information. Here, we present the Rapid TCR:Epitope Ranker (RAPTER) assay, a single cell RNA sequencing (scRNA-SEQ) method that uses primary human T cells and antigen presenting cells (APCs) to assess functional T cell reactivity. Using hash-tag oligonucleotide (HTO) coding and T cell activation-induced markers (AIM), RAPTER defines paired epitope specificity and TCR sequence and can include RNA- and protein-level T cell phenotype information. We demonstrate that RAPTER identified specific reactivities to viral and tumor antigens at sensitivities as low as 0.15% of total CD8+ T cells, and deconvoluted low-frequency circulating HPV16-specific T cell clones from a cervical cancer patient. The specificities of TCRs identified by RAPTER for MART1, EBV, and influenza epitopes were functionally confirmed in vitro. In summary, RAPTER identifies low-frequency T cell reactivities using primary cells from low blood volumes, and the resulting paired TCR:ligand information can directly enable immunogenic antigen selection from limited patient samples for vaccine epitope inclusion, antigen-specific TCR tracking, and TCR cloning for further therapeutic development.


Asunto(s)
Linfocitos T CD8-positivos , Epítopos de Linfocito T , Humanos , Receptores de Antígenos de Linfocitos T/genética , Membrana Celular
7.
Commun Biol ; 6(1): 447, 2023 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-37185301

RESUMEN

Efficacy of immune checkpoint inhibitors in cancers can be limited by CD8 T cell dysfunction or HLA-I down-regulation. Tumor control mechanisms independent of CD8/HLA-I axis would overcome these limitations. Here, we report potent CD4 T cell-mediated tumor regression and memory responses in humanized immune system (HIS) mice implanted with HT-29 colorectal tumors. The regressing tumors showed increased CD4 cytotoxic T lymphocyte (CTL) infiltration and enhanced tumor HLA-II expression compared to progressing tumors. The intratumoral CD4 T cell subset associated with tumor regression expressed multiple cytotoxic markers and exhibited clonal expansion. Notably, tumor control was abrogated by depletion of CD4 but not CD8 T cells. CD4 T cells derived from tumor-regressing mice exhibited HLA-II-dependent and tumor-specific killing ex vivo. Taken together, our study demonstrates a critical role of human CD4 CTLs in mediating tumor clearance independent of CD8 T cells and provides a platform to study human anti-tumor immunity in vivo.


Asunto(s)
Neoplasias , Linfocitos T Citotóxicos , Humanos , Ratones , Animales , Linfocitos T CD4-Positivos , Linfocitos T CD8-positivos , Neoplasias/metabolismo
8.
Cell Rep ; 41(10): 111769, 2022 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-36476866

RESUMEN

Monocytes are highly plastic immune cells that modulate antitumor immunity. Therefore, identifying factors that regulate tumor monocyte functions is critical for developing effective immunotherapies. Here, we determine that endogenous cancer cell-derived type I interferons (IFNs) control monocyte functional polarization. Guided by single-cell transcriptomic profiling of human and mouse tumors, we devise a strategy to distinguish and separate immunostimulatory from immunosuppressive tumor monocytes by surface CD88 and Sca-1 expression. Leveraging this approach, we show that cGAS-STING-regulated cancer cell-derived IFNs polarize immunostimulatory monocytes associated with anti-PD-1 immunotherapy response in mice. We also demonstrate that immunosuppressive monocytes convert into immunostimulatory monocytes upon cancer cell-intrinsic cGAS-STING activation. Consistently, we find that human cancer cells can produce type I IFNs that polarize monocytes, and our immunostimulatory monocyte gene signature is enriched in patient tumors that respond to anti-PD-1 immunotherapy. Our work exposes a role for cancer cell-derived IFNs in licensing monocyte functions that influence immunotherapy outcomes.


Asunto(s)
Interferón Tipo I , Neoplasias , Humanos , Ratones , Animales , Monocitos
9.
PLoS One ; 17(11): e0277849, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36399461

RESUMEN

Asthma is a polygenic chronic inflammatory respiratory disease devastating the quality of life and state economies. Therefore, utilization of natural products as a therapeutic approach has attained wider consideration for development of novel drugs for asthma management. Bromelain, a mixture of natural bioactive cysteine proteases abundantly found in pineapple stem, has allured attention for its pharmacological activities. However, poor stability in gastric milieu, high dose and immunogenicity associated with prolonged use hinders its oral use. Therefore, need exists to explore alternative route of bromelain administration to achieve its plausible benefits. The present study investigated the preclinical prospects of nasal administration of bromelain on systemic bioavailability, tissue distribution and it's in vivo anti-histaminic, bronchodilator and anti-asthmatic activity in animal models. Pharmacokinetic studies revealed 1.43-fold higher relative bioavailability with faster absorption of bromelain on nasal administration at one-fourth oral dose. The enhanced cellular uptake and localization of bromelain in tissues of lung was observed significantly. Furthermore, faster onset and enhanced antihistaminic, bronchodilator and anti-asthmatic activity on bromelain's nasal administration signified faster absorption and higher in vivo stability of bromelain. Nasal administration significantly achieved decrease in level of oxidative and immunological markers along with restoration of antioxidant enzymes at considerably one-fourth dose administered orally. These findings distinctly manifested that nasal administration could be a substantial and effective route for bromelain delivery with enduring competency in asthma management.


Asunto(s)
Ananas , Bromelaínas , Animales , Bromelaínas/farmacología , Distribución Tisular , Broncodilatadores , Calidad de Vida , Ananas/metabolismo
10.
Lancet Gastroenterol Hepatol ; 7(3): 219-229, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35065058

RESUMEN

BACKGROUND: Surgical resection of early stage hepatocellular carcinoma is standard clinical practice; however, most tumours recur despite surgery, and no perioperative intervention has shown a survival benefit. Neoadjuvant immunotherapy has induced pathological responses in multiple tumour types and might decrease the risk of postoperative recurrence in hepatocellular carcinoma. We aimed to evaluate the clinical activity of neoadjuvant cemiplimab (an anti-PD-1) in patients with resectable hepatocellular carcinoma. METHODS: For this single-arm, open-label, phase 2 trial, patients with resectable hepatocellular carcinoma (stage Ib, II, and IIIb) were enrolled and received two cycles of neoadjuvant cemiplimab 350 mg intravenously every 3 weeks followed by surgical resection. Eligible patients were aged 18 years or older, had confirmed resectable hepatocellular carcinoma, an Eastern Cooperative Oncology Group performance status of 0 or 1, and adequate liver function. Patients were excluded if they had metastatic disease, if the surgery was not expected to be curative, if they had a known additional malignancy requiring active treatment, or if they required systemic steroid treatment or any other immunosuppressive therapy. After resection, patients received an additional eight cycles of cemiplimab 350 mg intravenously every 3 weeks in the adjuvant setting. The primary endpoint was significant tumour necrosis on pathological examination (defined as >70% necrosis of the resected tumour). Secondary endpoints included delay of surgery, the proportion of patients with an overall response, change in CD8+ T-cell density, and adverse events. Tumour necrosis and response were analysed in all patients who received at least one dose of cemiplimab and completed surgical resection; safety and other endpoints were analysed in the intention-to-treat population. Patients underwent pre-treatment biopsies and blood collection throughout treatment. This trial is registered with ClinicalTrials.gov (NCT03916627, Cohort B) and is ongoing. FINDINGS: Between Aug 5, 2019, and Nov 25, 2020, 21 patients were enrolled. All patients received neoadjuvant cemiplimab, and 20 patients underwent successful resection. Of the 20 patients with resected tumours, four (20%) had significant tumour necrosis. Three (15%) of 20 patients had a partial response, and all other patients maintained stable disease. 20 (95%) patients had a treatment-emergent adverse event of any grade during the neoadjuvant treatment period. The most common adverse events of any grade were increased aspartate aminotransferase (in four patients), increased blood creatine phosphokinase (in three), constipation (in three), and fatigue (in three). Seven patients had grade 3 adverse events, including increased blood creatine phosphokinase (in two patients) and hypoalbuminaemia (in one). No grade 4 or 5 events were observed. One patient developed pneumonitis, which led to a delay in surgery by 2 weeks. INTERPRETATION: This report is, to our knowledge, the largest clinical trial of a neoadjuvant anti-PD-1 monotherapy reported to date in hepatocellular carcinoma. The observed pathological responses to cemiplimab in this cohort support the design of larger trials to identify the optimal treatment duration and definitively establish the clinical benefit of preoperative PD-1 blockade in patients with hepatocellular carcinoma. FUNDING: Regeneron Pharmaceuticals.


Asunto(s)
Anticuerpos Monoclonales Humanizados/administración & dosificación , Antineoplásicos Inmunológicos/administración & dosificación , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales Humanizados/efectos adversos , Antineoplásicos Inmunológicos/efectos adversos , Aspartato Aminotransferasas/sangre , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/cirugía , Creatina Quinasa/sangre , Femenino , Humanos , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/cirugía , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante
11.
Sci Adv ; 7(20)2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33990328

RESUMEN

T cell receptor (TCR) antigen-specific recognition is essential for the adaptive immune system. However, building a TCR-antigen interaction map has been challenging due to the staggering diversity of TCRs and antigens. Accordingly, highly multiplexed dextramer-TCR binding assays have been recently developed, but the utility of the ensuing large datasets is limited by the lack of robust computational methods for normalization and interpretation. Here, we present a computational framework comprising a novel method, ICON (Integrative COntext-specific Normalization), for identifying reliable TCR-pMHC (peptide-major histocompatibility complex) interactions and a neural network-based classifier TCRAI that outperforms other state-of-the-art methods for TCR-antigen specificity prediction. We further demonstrated that by combining ICON and TCRAI, we are able to discover novel subgroups of TCRs that bind to a given pMHC via different mechanisms. Our framework facilitates the identification and understanding of TCR-antigen-specific interactions for basic immunological research and clinical immune monitoring.


Asunto(s)
Complejo Mayor de Histocompatibilidad , Receptores de Antígenos de Linfocitos T , Antígenos , Antígenos de Histocompatibilidad/metabolismo , Unión Proteica , Receptores de Antígenos de Linfocitos T/metabolismo , Especificidad del Receptor de Antígeno de Linfocitos T
12.
Oncoimmunology ; 9(1): 1758602, 2020 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-32923116

RESUMEN

Clinical observations suggest that responses to cancer immunotherapy are correlated with intra-tumoral T cell receptor (TCR) clonality, tumor mutation burden (TMB) and host HLA genotype, highlighting the importance of host T cell recognition of tumor antigens. However, the dynamic interplay between T cell activation state and changes in TCR repertoire in driving the identification of potential immunodominant antigen(s) remains largely unexplored. Here, we performed single-cell RNA-sequencing on CD8+ tumor-infiltrating T cells (TILs) using the murine colorectal tumor model MC38 to identify unique TCR sequences and validate their tumor reactivity. We found that the majority of clonally expanded TILs are tumor-reactive and their TCR repertoire is unique amongst individual MC38 tumor-bearing mice. Our query identified that multiple expanded TCR clones recognized the retroviral epitope p15E as an immunodominant antigen. In addition, we found that the endogenous retroviral genome encoding for p15E is highly expressed in MC38 tumors, but not in normal tissues, due to epigenetic derepression. Further, we demonstrated that the p15E-specific TILs exhibit an activated phenotype and an increase in frequency upon treatment with anti-41BB and anti-PD-1 combination immunotherapy. Importantly, we showed that although p15E-specific TILs are not required to mount a primary anti-tumor response, they contributed to the development of strong immune memory. Overall our results revealed that endogenous retroviral antigens expressed by tumor cells may represent an important and underappreciated category of tumor antigens that could be readily targeted in the clinic.


Asunto(s)
Retrovirus Endógenos , Neoplasias , Animales , Inmunoterapia , Activación de Linfocitos , Ratones , Neoplasias/terapia , Receptores de Antígenos de Linfocitos T/genética
13.
Am J Cancer Res ; 10(6): 1919-1920, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32642300

RESUMEN

[This corrects the article on p. 1252 in vol. 7, PMID: 28670489.].

14.
Commun Biol ; 3(1): 355, 2020 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-32641748

RESUMEN

The endogenous anti-tumor responses are limited in part by the absence of tumor-reactive T cells, an inevitable consequence of thymic central tolerance mechanisms ensuring prevention of autoimmunity. Here we show that tumor rejection induced by immune checkpoint blockade is significantly enhanced in Aire-deficient mice, the epitome of central tolerance breakdown. The observed synergy in tumor rejection extended to different tumor models, was accompanied by increased numbers of activated T cells expressing high levels of Gzma, Gzmb, Perforin, Cxcr3, and increased intratumoural levels of Cxcl9 and Cxcl10 compared to wild-type mice. Consistent with Aire's central role in T cell repertoire selection, single cell TCR sequencing unveiled expansion of several clones with high tumor reactivity. The data suggest that breakdown in central tolerance synergizes with immune checkpoint blockade in enhancing anti-tumor immunity and may serve as a model to unmask novel anti-tumor therapies including anti-tumor TCRs, normally purged during central tolerance.


Asunto(s)
Inhibidores de Puntos de Control Inmunológico/inmunología , Tolerancia Inmunológica/inmunología , Neoplasias Experimentales/inmunología , Poliendocrinopatías Autoinmunes/inmunología , Factores de Transcripción/deficiencia , Animales , Linfocitos T CD8-positivos/inmunología , Melanoma Experimental/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Trasplante de Neoplasias , Linfocitos T/inmunología , Escape del Tumor/inmunología , Proteína AIRE
15.
Tumour Biol ; 42(4): 1010428320914477, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32342732

RESUMEN

Triple-negative breast cancers are the most aggressive subtypes with poor prognosis due to lack of targeted cancer therapy. Recently, we reported an association of A-kinase anchor protein 4 expression with various clinico-pathological parameters of breast cancer patients. In this context, we examined the effect of knockdown of A-kinase anchor protein 4 on cell cycle, apoptosis, cellular proliferation, colony formation, migration, and invasion in triple-negative breast cancer cells. We also examined the synergistic cytotoxic effect of paclitaxel on A-kinase anchor protein 4 downregulated triple-negative breast cancer cells. Knockdown of A-kinase anchor protein 4 resulted in significant reduction in cellular growth and migratory abilities. Interestingly, we also observed enhanced cell death in A-kinase anchor protein 4 downregulated cells treated with paclitaxel. Knockdown of A-kinase anchor protein 4 in cell cycle resulted in G0/G1 phase arrest. Knockdown of A-kinase anchor protein 4 also led to increased reactive oxygen species generation as a result of upregulation of NOXA and CHOP. In addition, levels of cyclins, cyclin-dependent kinases, anti-apoptotic molecules, and mesenchymal markers were reduced in A-kinase anchor protein 4 downregulated cells. Moreover, downregulation of A-kinase anchor protein 4 also caused tumor growth reduction in in vivo studies. These data together suggest that A-kinase anchor protein 4 downregulation inhibits various malignant properties and enhances the cytotoxic effect of paclitaxel, and this combinatorial approach could be useful for triple-negative breast cancer treatment.


Asunto(s)
Proteínas de Anclaje a la Quinasa A/deficiencia , Neoplasias de la Mama Triple Negativas/genética , Proteínas de Anclaje a la Quinasa A/genética , Proteínas de Anclaje a la Quinasa A/metabolismo , Animales , Apoptosis/efectos de los fármacos , Apoptosis/genética , Biomarcadores , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Modelos Animales de Enfermedad , Femenino , Técnicas de Silenciamiento del Gen , Silenciador del Gen , Humanos , Inmunofenotipificación , Ratones , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/genética , Paclitaxel/farmacología , Especies Reactivas de Oxígeno/metabolismo , Neoplasias de la Mama Triple Negativas/metabolismo , Neoplasias de la Mama Triple Negativas/patología , Ensayos Antitumor por Modelo de Xenoinjerto
16.
J Indian Soc Periodontol ; 24(2): 182-185, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32189849

RESUMEN

Combined endodontic periodontal lesion is one of the most challenging dental conditions as making a definite diagnosis and henceforth treatment plan is a daunting task. The prognosis of complex lesion involving both endodontic and periodontic components is complex, but success rate can be improved with regenerative therapies. However, there is paucity of literature regarding its effectiveness in the clinical scenario as only few case reports have been documented in literature for the use of platelet-rich derivatives in regenerative osseous surgery requiring both endodontic and periodontal treatment. We are hereby presenting three cases requiring both endo and perio treatment. The first two cases involve mandibular first molar and maxillary first molar, respectively. The third case involves maxillary central incisor. In all the cases, first, endodontic treatment was initiated, then open flap curettage along with alloplastic bone substitutes was done. Platelet-rich fibrin and platelet-rich plasma were used along with. Three of the treated cases showed significant improvement radiographically and clinically. There was gain in clinical attachment, reduction in probing depth, and radiographic bone fill. Autologous platelet-rich derivative can be used in combination with alloplastic bone substitute for the management of endo-perio cases. Further long-term studies are needed to explore the clinical effectiveness of platelet-rich derivatives and predicting the probability of success of periodontal therapy.

17.
J Pharm Biomed Anal ; 174: 711-717, 2019 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-31288194

RESUMEN

Duranta erecta L.is a valuable herb used in traditional system of medicine in India and China for the treatment of malaria and abscesses. The presence of phenylethanoid (e.g., acteoside as major bioactive) in addition to iridoid and flavonoids glycosides are mainly responsible for reported pharmacological properties. Although D. erecta is widely used in many Asian countries, the quality assurance of raw herb and its derived products are still in question, due to the lack of validated protocol. Current Indian guidelines for quality assurance of phytopharmaceutical product demands accurate determination of minimum four chemicals. Moreover, there is no chromatographic method to simultaneously analyse acteoside, isoacteoside, durantoside I, quercetin, and methylapigenin-7-O-ß-D-glucopyranuronate in D. erecta. The present study establishes a systematic approach for the quality evaluation of D. erecta with efficient and validated UPLC-PDA method that simultaneously analyses the five bioactive marker chemicals in D. erecta. A fast, sensitive, and reliable ultraperformance liquid chromatography-photodiode array (UPLC-PDA) method was developed for the quantification five marker compounds-acteoside, isoacteoside, durantoside-I, quercetin, and methylapigenin-7-O-ß-D-glucopyranuronate in D. erecta. The optimized UPLC conditions on Reverse phase column Phenomenex Luna® (C18, 2.5µm, 2.0×100mm)) and binary gradient elution resulted in best separation for all five targeted phytoconstituents. Validation characteristics viz. linearity (r2 >0.999), accuracy (%RSD<2.0), precision (%RSD, 1.62-2.59), recovery (99-101%), and sensitivity (LOD- 0.27-0.40µg mL-1; LOQ- 0.90-1.35µgmL-1) were satisfying the ICH criteria. Uncertainty in the measurement was also estimated using method validation data and other sources to fulfil the technical requirement of ISO 17025:2017. It is the first validated method that provides the simultaneous and accurate analysis of five bioactive phytoconstituents of D. erecta in short time with defined traceability and accuracy profile. Further, it delivers a holistic quality analysis of raw medicinal herb and its preparation.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Medicamentos Herbarios Chinos/análisis , Flavonoles/análisis , Glicósidos/análisis , Iridoides/análisis , Alcohol Feniletílico/análisis , Calibración , Glucósidos/análisis , India , Límite de Detección , Modelos Lineales , Fenoles/análisis , Extractos Vegetales/análisis , Reproducibilidad de los Resultados , Incertidumbre
18.
Pharmaceutics ; 11(4)2019 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-30987266

RESUMEN

While melanoma remains a challenge for oncologists, possibilities are being continuously explored to fight resistant metastatic melanoma more effectively. Eugenol is reported to inhibit survivin protein in breast cancer cells. Survivin is also overexpressed by melanoma cells, and is known to impart resistance to them against chemotherapy-induced apoptosis. To be able to fight resistant melanoma, we formulated hyaluronic acid (HA)-coated liposomes loaded with an effective combination of anti-melanoma agents (Dacarbazine and Eugenol), using a solvent injection method. Quality-by-Design (QbD) was applied to optimize and obtain a final formulation with the desired quality attributes, and within an acceptable size range. The optimized formulation was then subjected to performance analysis in cell lines. Coated-Dacarbazine Eugenol Liposomes were found to possess 95.08% cytotoxicity at a dacarbazine concentration of 0.5 µg/mL, while Dacarbazine Solution showed only 10.20% cytotoxicity at the same concentration. The number of late apoptotic cells was also found to be much higher (45.16% vs. 8.43%). Furthermore, migration assay and proliferation study also revealed significantly higher inhibition of cell migration and proliferation by Coated-Dacarbazine Eugenol Liposomes, signifying its potential against metastasis. Thus, surface-functionalized dacarbazine- and eugenol-loaded liposomes hold great promise against resistant and aggressive metastatic melanoma, with much less unwanted cytotoxicity and reduced doses of the chemotherapeutic agent.

19.
World J Plast Surg ; 8(1): 12-17, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30873357

RESUMEN

BACKGROUND: Gingival recession is a frequent issue encountered by both the clinician and the patient. This study was aimed to assess the predictability of the free gingival graft as a single step procedure in terms of root coverage and aesthetics in Miller Class I and II mandibular gingival recession. METHODS: Ten patients (4 males, 6 females) aged 25-30 years with a total of 12 mandibular sites having Miller class I and II recession were selected. All recession sites were treated with single step free gingival graft procedure. Clinical parameters like recession depth, recession width, width of attached gingiva, probing depth and clinical attachment level were recorded at baseline, 6 and 9 months. Visual analog score at 1, 6 and 9 months postoperatively was provided. RESULTS: There was a reduction in mean recession depth from 3.66±1.20 to 0.91±0.99 mm suggesting coverage of 82% over a period of 9 months. There was statistically significant gain in clinical attachment level and width of attached gingiva. Aesthetically, it was acceptable by patients as measured by visual analog scores. CONCLUSION: Free gingival graft as a single step procedure is acceptable in terms of root coverage and aesthetics.

20.
Pancreas ; 48(3): 387-395, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30768576

RESUMEN

OBJECTIVES: Patients with chronic pancreatitis (CP) are at increased risk of low bone mineral density (BMD), although the prevalence of low BMD in patients with CP in the United States is lacking. We aimed to determine the prevalence of low BMD and identify potential risk factors, including hypogonadism and use of opioid medications, in subjects with CP in the United States. METHODS: This was a prospective, observational study. Subjects with CP underwent dual-energy x-ray absorptiometry scan. Blood was assayed for vitamin D, sex hormones, and a metabolic panel. History was obtained for fractures, menopause, hypogonadal symptoms, and opioid medication doses. Low BMD was defined by both World Health Organization and the International Society for Clinical Densitometry criteria. RESULTS: Depending on criteria used, 37% to 55% of our cohort had low BMD. Subjects with low and normal BMD had similar vitamin D levels. Hypogonadism was present in 27% of nonmenopausal subjects and was associated with reduced lumbar spine BMD in subjects 30 years or older. CONCLUSIONS: Patients with CP are at increased risk of low BMD, which is likely multifactorial. Hypogonadism, possibly related to opioid pain medications, may be an independent risk factor for low BMD in CP.


Asunto(s)
Densidad Ósea , Hipogonadismo/epidemiología , Pancreatitis Crónica/epidemiología , Vitamina D/sangre , Absorciometría de Fotón , Adulto , Comorbilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , Factores de Riesgo , Estados Unidos/epidemiología
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