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1.
Cancer Immunol Immunother ; 71(8): 1837-1849, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34999916

RESUMEN

Talimogene Laherparepvec (OncoVEXmGMCSF), an oncolytic virus, immune checkpoint inhibitor anti-programmed cell death protein 1 (anti-PD1), and BRAF inhibition (BRAFi), are all clinically approved for treatment of melanoma patients and are effective through diverse mechanisms of action. Individually, these therapies also have an effect on the tumor immune microenvironment (TIME). Evaluating the combination effect of these three therapies on the TIME can help determine when combination therapy is most appropriate for further study. In this study, we use a transgenic murine melanoma model (Tyr::CreER; BRAFCA/+; PTENflox/flox), to evaluate the TIME in response to combinations of BRAFi, anti-PD1, and OncoVEXmGMCSF. We find that mice treated with the triple combination BRAFi + anti-PD1 + OncoVEXmGMCSF have decreased tumor growth compared to BRAFi alone and prolonged survival compared to control. Flow cytometry shows an increase in percent CD8 + /CD3 + cytotoxic T Lymphocytes (CTLs) and a decrease in percent FOXP3 + /CD4 + T regulatory cells (Tregs) in tumors treated with OncoVEXmGMCSF compared to mice not treated with OncoVEXmGMCSF. Immunogenomic analysis at 30d post-treatment shows an increase in Th1 and interferon-related genes in mice receiving OncoVEXmGMCSF + BRAFi. In summary, treatment with combination BRAFi + anti-PD1 + OncoVEXmGMCSF is more effective than any single treatment in controlling tumor growth, and groups receiving OncoVEXmGMCSF had more tumoral infiltration of CTLs and less intratumoral Tregs in the TIME. This study provides rational basis to combine targeted agents, oncolytic viral therapy, and checkpoint inhibitors in the treatment of melanoma.


Asunto(s)
Antineoplásicos , Melanoma , Viroterapia Oncolítica , Virus Oncolíticos , Animales , Antineoplásicos/uso terapéutico , Factores Inmunológicos/uso terapéutico , Inmunoterapia , Melanoma/tratamiento farmacológico , Ratones , Proteínas Proto-Oncogénicas B-raf/genética , Microambiente Tumoral
2.
Eur J Nucl Med Mol Imaging ; 46(11): 2298-2310, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31346755

RESUMEN

PURPOSE: An imaging-based stratification tool is needed to identify melanoma patients who will benefit from anti Programmed Death-1 antibody (anti-PD1). We aimed at identifying biomarkers for survival and response evaluated in lymphoid tissue metabolism in spleen and bone marrow before initiation of therapy. METHODS: This retrospective study included 55 patients from two institutions who underwent 18F-FDG PET/CT before anti-PD1. Parameters extracted were SUVmax, SUVmean, HISUV (SUV-based Heterogeneity Index), TMTV (total metabolic tumor volume), TLG (total lesion glycolysis), BLR (Bone marrow-to-Liver SUVmax ratio), and SLR (Spleen-to-Liver SUVmax ratio). Each parameter was dichotomized using the median as a threshold. Association with survival, best overall response (BOR), and transcriptomic analyses (NanoString assay) were evaluated using Cox prediction models, Wilcoxon tests, and Spearman's correlation, respectively. RESULTS: At 20.7 months median follow-up, 33 patients had responded, and 29 patients died. Median PFS and OS were 11.4 (95%CI 2.7-20.2) and 28.5 (95%CI 13.4-43.8) months. TMTV (>25cm3), SLR (>0.77), and BLR (>0.79) correlated with shorter survival. High TMTV (>25 cm3), SLR (>0.77), and BLR (>0.79) correlated with shorter survival, with TMTV (HR PFS 2.2, p = 0.02, and HR OS 2.5, p = 0.02) and BLR (HR OS 2.3, p = 0.04) remaining significant in a multivariable analysis. Low TMTV and TLG correlated with BOR (p = 0.03). Increased glucose metabolism in bone marrow (BLR) was associated with transcriptomic profiles including regulatory T cell markers (p < 0.05). CONCLUSION: Low tumor burden correlates with survival and objective response while hematopoietic tissue metabolism correlates inversely with survival. These biomarkers should be further evaluated for potential clinical application.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Inmunoterapia , Melanoma/inmunología , Melanoma/terapia , Tomografía de Emisión de Positrones , Receptor de Muerte Celular Programada 1/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Biopsia , Fluorodesoxiglucosa F18 , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad , Metástasis de la Neoplasia , Pronóstico , Estudios Retrospectivos , Transcriptoma , Resultado del Tratamiento , Adulto Joven
3.
J Virol ; 90(18): 8302-13, 2016 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-27384660

RESUMEN

UNLABELLED: Cell culture (cc)-derived hepatitis B virus (HBV) can infect differentiated HepaRG cells, but efficient infection requires addition of polyethylene glycol (PEG) during inoculation. Identification of sodium taurocholate cotransporting polypeptide (NTCP) as an HBV receptor enabled ccHBV infection of NTCP reconstituted HepG2 cells, although very little hepatitis B surface antigen (HBsAg) is produced. We found infection by patient serum-derived HBV (sHBV), which required purification of viral particles through ultracentrifugation or PEG precipitation, was PEG independent and much more efficient in HepaRG cells than in HepG2/NTCP cells. In contrast to hepatitis B e antigen (HBeAg), HBsAg was not a reliable marker of productive sHBV infection at early time points. A low HBsAg/HBeAg ratio by ccHBV-infected HepG2/NTCP cells was attributable to dimethyl sulfoxide (DMSO) in culture medium, NTCP overexpression, and HBV genotype D. HepG2/NTCP cells released more viral antigens than HepG2 cells after HBV genome delivery by adeno-associated virus, and stable expression of NTCP in a ccHBV producing cell line increased viral mRNAs, proteins, replicative DNA, and covalently closed circular DNA. NTCP protein expression in HepG2/NTCP cells, despite being driven by the cytomegalovirus promoter, was markedly increased by DMSO treatment. This at least partly explains ability of DMSO to promote ccHBV infection in such cell lines. In conclusion, NTCP appeared inefficient to mediate infection by serum-derived HBV. It could promote HBV RNA transcription while inhibiting HBsAg secretion. Efficient PEG-independent sHBV infection of HepaRG cells permits comparative studies of diverse clinical HBV isolates and will help identify additional factors on virion surface promoting attachment to hepatocytes. IMPORTANCE: Currently in vitro infection with hepatitis B virus (HBV) depends on cell culture-derived HBV inoculated in the presence of polyethylene glycol. We found patient serum-derived HBV could efficiently infect differentiated HepaRG cells independent of polyethylene glycol, which represents a more physiological infection system. Serum-derived HBV has poor infectivity in HepG2 cells reconstituted with sodium taurocholate cotransporting polypeptide (NTCP), the currently accepted HBV receptor. Moreover, HepG2/NTCP cells secreted very little hepatitis B surface antigen after infection with cell culture-derived HBV, which was attributed to NTCP overexpression, genotype D virus, and dimethyl sulfoxide added to culture medium. NTCP could promote HBV RNA transcription, protein expression, and DNA replication in HepG2 cells stably transfected with HBV DNA, while dimethyl sulfoxide could increase NTCP protein level despite transcriptional control by a cytomegalovirus promoter. Therefore, this study revealed several unusual features of NTCP as an HBV receptor and established conditions for efficient serum virus infection in vitro.


Asunto(s)
Virus de la Hepatitis B/fisiología , Hepatocitos/virología , Transportadores de Anión Orgánico Sodio-Dependiente/metabolismo , Receptores Virales/metabolismo , Simportadores/metabolismo , Acoplamiento Viral , Línea Celular , ADN Viral/biosíntesis , Antígenos de la Hepatitis B/biosíntesis , Humanos , ARN Mensajero/biosíntesis , ARN Viral/biosíntesis , Liberación del Virus
4.
EClinicalMedicine ; 51: 101561, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35865740

RESUMEN

Background: Maori, the indigenous people of New Zealand, have traditionally used the kanuka tree as part of their healing system, Rongoa Maori, and the oil from the kanuka tree has demonstratable anti-inflammatory and anti-bacterial properties. This trial investigated the efficacy and safety of a 3% kanuka oil (KO) cream compared to vehicle control (VC) for the topical treatment of eczema. The trial was conducted through a nationwide community pharmacy research network. Methods: This single-blind, parallel-group, randomised, vehicle-controlled trial was undertaken in 11 research trained community pharmacies across New Zealand. Eighty adult participants with self-reported moderate-to-severe eczema, assessed by Patient Orientated Eczema Measure (POEM) were randomised by blinded investigators to apply 3% KO cream or VC topically, twice daily, for six weeks. Randomisation was stratified by site and eczema severity, moderate versus severe. Primary outcome was difference in POEM scores at week six between groups by intention to treat. The study is registered on the Australian New Zealand Clinical Trial Registry (ANZCTR) reference number, ACTRN12618001754235. Findings: Eighty participants were recruited between 17 May 2019 and 10 May 2021 (41 KO group, 39 VC group). Mean POEM score (standard deviation) improved between baseline and week six for KO group, 18·4 (4·4) to 6·8 (5·5), and VC group, 18·7 (4·5) to 9·8 (6·5); mean difference between groups (95% confidence interval) was -3·1 (-6·0 to -0·2), p = 0·036. There were three adverse events reported in the KO group related to the intervention and two in the control group. Interpretation: The KO group had a significant improvement in POEM score compared to VC. Rates of adverse events and withdrawals were similar between groups with no serious adverse events reported. Treatment acceptability was high for both groups across all domains. Our results suggest that in adults with moderate-to-severe eczema, the addition of KO to a daily emollient regimen led to a reduction in POEM score compared to VC. KO may represent an effective, safe, and well tolerated treatment for moderate-to-severe eczema in adults. Funding: Hikurangi Bioactives (Ruatoria, New Zealand) and HoneyLab (Tauranga, New Zealand), supported by a grant from Callaghan Innovation.

5.
Emerg Med Australas ; 32(3): 409-415, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31828975

RESUMEN

OBJECTIVE: We aimed to describe the impact on the single ED serving Dunedin, New Zealand, following the introduction of an electric-scooter (e-scooter) sharing service. METHODS: A retrospective cohort study comparing the number of vehicle related injuries during identical 6-week periods in 2018 and 2019 was performed. A descriptive analysis of the subset of e-scooter related presentations was undertaken. RESULTS: A total of 172 and 228 vehicle related injury presentations were identified in samples from 2018 and 2019, respectively. During the 2018 study period zero e-scooter related ED presentations were identified. In 2019 there were 56 e-scooter related ED presentations (P-value <0.001) representing 54 events. There were 52 car, 21 motorbike and 62 bicycle related presentations during the same 2019 time period. Further descriptive analysis showed the majority of e-scooter presentations were for minor injury. Fractures or dislocations were found in 17 (32%) patients and 14 (26%) patients sustained a head injury, one of which was severe. Isolated minor musculoskeletal injuries were seen in 25 (46%) patients. On average one ED bed was occupied by an e-scooter patient for 2 h and 44 min each day during the 6-week study period in 2019. CONCLUSION: The introduction of an e-scooter sharing service resulted in a new injury hazard. Our study presents the number of e-scooter related ED presentations relative to other vehicles related injury visits and describes the injury patterns associated with e-scooter use which may inform future public policy.


Asunto(s)
Traumatismos Craneocerebrales , Fracturas Óseas , Servicio de Urgencia en Hospital , Humanos , Motocicletas , Estudios Retrospectivos
6.
Clin Nucl Med ; 45(4): 267-275, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32108700

RESUMEN

PURPOSE: Investigate the ability of F-fluorothymidine (FLT) PET combined with CT at 6 weeks to predict treatment response at 12 weeks after treatment with pembrolizumab. METHODS: Five patients with unresectable stage IV melanoma were included in this single-institution pilot study. Patients underwent FLT-PET/CT (baseline and 6 weeks) and CT (baseline and 12 weeks). FLT-PET/CT response and CT response were assessed using PET Response Criteria in Solid Tumors and immune Response Evaluation Criteria in Solid Tumors, respectively. Patients were categorized as responders (complete response, partial response) and nonresponders (stable disease, progressive disease). Agreement between 6-week FLT-PET/CT and 12-week CT was calculated using Cohen kappa's agreement. Eight baseline FLT-PET/CT parameters were extracted: SUVmax, SUVpeak, SUVSD, SUVmean, proliferative tumor volume, total lesion proliferation, bone marrow-to-liver SUVmax ratio, and spleen-to-liver SUVmax ratio. Eight delta-parameters were extracted at 6 weeks by calculating variation in FLT uptake as percentage change from baseline. RESULTS: Agreement between 6-week FLT-PET/CT and 12-week CT was kappa = 0.615, P = 0.025. Three of 5 patients were categorized as responders on CT by immune Response Evaluation Criteria in Solid Tumors. At baseline, responders had a lower mean proliferative tumor volume and a higher bone marrow-to-liver SUVmax ratio. At 6 weeks, responders demonstrated a decrease in tumor volume and tumor proliferation. CONCLUSIONS: Our study illustrates the potential for FLT-PET/CT as an early predictor of response for patients with metastatic melanoma on anti-PD1 immunotherapy. Larger studies are indicated to confirm these findings.


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Antineoplásicos Inmunológicos/uso terapéutico , Melanoma/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Adulto , Anciano , Didesoxinucleósidos , Femenino , Humanos , Masculino , Melanoma/tratamiento farmacológico , Melanoma/patología , Persona de Mediana Edad , Tomografía Computarizada por Tomografía de Emisión de Positrones/normas , Valor Predictivo de las Pruebas , Radiofármacos , Carga Tumoral
7.
Cancer Res ; 80(5): 1078-1087, 2020 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-31948941

RESUMEN

Patients with resected stage II-III melanoma have approximately a 35% chance of death from their disease. A deeper understanding of the tumor immune microenvironment (TIME) is required to stratify patients and identify factors leading to therapy resistance. We previously identified that the melanoma immune profile (MIP), an IFN-based gene signature, and the ratio of CD8+ cytotoxic T lymphocytes (CTL) to CD68+ macrophages both predict disease-specific survival (DSS). Here, we compared primary with metastatic tumors and found that the nuclei of tumor cells were significantly larger in metastases. The CTL/macrophage ratio was significantly different between primary tumors without distant metastatic recurrence (DMR) and metastases. Patients without DMR had higher degrees of clustering between tumor cells and CTLs, and between tumor cells and HLA-DR+ macrophages, but not HLA-DR- macrophages. The HLA-DR- subset coexpressed CD163+CSF1R+ at higher levels than CD68+HLA-DR+ macrophages, consistent with an M2 phenotype. Finally, combined transcriptomic and multiplex data revealed that densities of CD8 and M1 macrophages correlated with their respective cell phenotype signatures. Combination of the MIP signature with the CTL/macrophage ratio stratified patients into three risk groups that were predictive of DSS, highlighting the potential use of combination biomarkers for adjuvant therapy. SIGNIFICANCE: These findings provide a deeper understanding of the tumor immune microenvironment by combining multiple modalities to stratify patients into risk groups, a critical step to improving the management of patients with melanoma.


Asunto(s)
Biomarcadores de Tumor/análisis , Macrófagos/inmunología , Melanoma/mortalidad , Piel/patología , Microambiente Tumoral/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/inmunología , Femenino , Técnica del Anticuerpo Fluorescente , Antígenos HLA-DR/inmunología , Antígenos HLA-DR/metabolismo , Humanos , Estimación de Kaplan-Meier , Macrófagos/metabolismo , Masculino , Melanoma/sangre , Melanoma/genética , Melanoma/inmunología , Persona de Mediana Edad , Estadificación de Neoplasias , Estudios Retrospectivos , Medición de Riesgo/métodos , Piel/inmunología , Linfocitos T Citotóxicos/inmunología , Transcriptoma/inmunología , Microambiente Tumoral/genética , Adulto Joven
8.
Hematol Oncol Clin North Am ; 33(2): 291-299, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30833001

RESUMEN

Immunotherapy has drastically improved the prognosis of many patients with cancer, but it can also lead to severe immune-related adverse events. Biomarkers, which are molecular markers that indicate a patient's disease outcome or a patient's response to treatment, are therefore crucial to helping clinicians weigh the potential benefits of immunotherapy against its potential toxicities. Immunohistochemistry (IHC) has thus far been a powerful technique for discovery and use of biomarkers such as CD8+ tumor-infiltrating lymphocytes. However, IHC has limited reproducibility. Thus, if more IHC-based biomarkers are to reach the clinic, refinement of the technique using multiplexing or automation is key.


Asunto(s)
Biomarcadores de Tumor , Linfocitos T CD8-positivos/inmunología , Inmunoterapia , Linfocitos Infiltrantes de Tumor/inmunología , Neoplasias , Biomarcadores de Tumor/inmunología , Biomarcadores de Tumor/metabolismo , Humanos , Inmunohistoquímica , Neoplasias/diagnóstico , Neoplasias/inmunología , Neoplasias/metabolismo , Neoplasias/terapia , Pronóstico
9.
Clin Cancer Res ; 25(8): 2494-2502, 2019 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-30647081

RESUMEN

PURPOSE: Biomarkers are needed to stratify patients with stage II-III melanoma for clinical trials of adjuvant therapy because, while immunotherapy is protective, it also confers the risk of severe toxicity. We previously defined and validated a 53-immune gene melanoma immune profile (MIP) predictive both of distant metastatic recurrence and of disease-specific survival (DSS). Here, we test MIP on a third independent population. EXPERIMENTAL DESIGN: A retrospective cohort of 78 patients with stage II-III primary melanoma was analyzed using the NanoString assay to measure expression of 53 target genes, and MIP score was calculated. Statistical analysis correlating MIP with DSS, overall survival, distant metastatic recurrence, and distant metastasis-free interval was performed using ROC curves, Kaplan-Meier curves, and standard univariable and multivariable Cox proportional hazards models. RESULTS: MIP significantly distinguished patients with distant metastatic recurrence from those without distant metastatic recurrence using ROC curve analysis (AUC = 0.695; P = 0.008). We defined high- and low-risk groups based on the cutoff defined by this ROC curve and find that MIP correlates with both DSS and overall survival by ROC curve analysis (AUC = 0.719; P = 0.004 and AUC = 0.698; P = 0.004, respectively). Univariable Cox regression reveals that a high-risk MIP score correlates with DSS (P = 0.015; HR = 3.2). CONCLUSIONS: MIP identifies patients with low risk of death from melanoma and may constitute a clinical tool to stratify patients with stage II-III melanoma for enrollment in clinical trials.


Asunto(s)
Biomarcadores de Tumor , Susceptibilidad a Enfermedades , Inmunidad/genética , Melanoma/diagnóstico , Melanoma/etiología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Perfilación de la Expresión Génica , Humanos , Masculino , Melanoma/mortalidad , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Especies Reactivas de Oxígeno , Estudios Retrospectivos , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/etiología , Neoplasias Cutáneas/mortalidad , Adulto Joven , Melanoma Cutáneo Maligno
10.
PLoS One ; 11(11): e0165227, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27802297

RESUMEN

We previously isolated AF20, a murine monoclonal antibody that recognizes a cell surface glycoprotein of approximately 90-110 kDa. The AF20 antigen is specifically expressed in human hepatoma and colon cancer cell lines, and thus could serve as a cancer biomarker. To uncover the molecular identity of the AF20 antigen, a combination of ion-exchange chromatography, immunoprecipitation, and SDS-polyacrylamide gel electrophoresis was employed to purify the AF20 antigen followed by trypsin digestion and mass spectrometry. Surprisingly, three host proteins were thus purified from human hepatoma and colon cancer cell lines: transferrin receptor 1 (TFR1), heat shock protein 90 (HSP90), and Na+/K+ ATPase or Mg++ ATPase. Co-immunoprecipitation followed by Western blot analysis confirmed interaction among the three proteins. However, only the cDNA encoding TFR1 conferred strong cell surface staining by the AF20 antibody following its transient transfection into a cell line lacking endogenous AF20. In support of the molecular identity of AF20 as TFR1, diferric but not iron-free transferrin could prevent AF20 antigen-antibody interaction during immunoprecipitation. Moreover, very similar patterns of AF20 and TFR1 overexpression was documented in colon cancer tissues. In conclusion, AF20 is glycosylated TFR1. This finding could explain the molecular structure of AF20, its cell surface localization, as well as overexpression in cancer cells. Glycosylated TFR1 should serve as a usefulness target for anti-cancer therapy, or a vehicle for delivery of anti-tumor drugs with high affinity and specificity. The biological significance of the complex formation between TFR1, HSP90, and/or transporting ATPase warrants further investigation.


Asunto(s)
Adenosina Trifosfatasas/metabolismo , Antígenos de Neoplasias/metabolismo , Transporte Biológico/fisiología , Proteínas HSP90 de Choque Térmico/metabolismo , Receptores de Transferrina/metabolismo , Animales , Células COS , Carcinoma Hepatocelular/metabolismo , Línea Celular , Línea Celular Tumoral , Chlorocebus aethiops , Neoplasias del Colon/metabolismo , Glicosilación , Células Hep G2 , Humanos , Hierro/metabolismo , Neoplasias Hepáticas/metabolismo , Ratones , Células 3T3 NIH , Unión Proteica/fisiología , Transferrina/metabolismo
11.
Int Immunopharmacol ; 4(9): 1209-15, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15251116

RESUMEN

Glucans are microbial cell wall carbohydrates that are shed into the circulation of patients with infections. Glucans are immunomodulatory and have structures that are influenced by bacterial or fungal species and growth conditions. We developed a method to covalently label carbohydrates with a fluorophore on the reducing terminus, and used the method to study the pharmacokinetics following intravenous administration of three highly purified and characterized glucans (glucan phosphate, laminarin and scleroglucan) that varied according to molecular size, branching frequency and solution conformation. Elimination half-life was longer (3.8+/-0.8 vs. 2.6+/-0.2 and 3.1+/-0.6 h) and volume of distribution lower (350+/-88 ml/kg vs. 540+/-146 and 612+/-154 ml/kg) for glucan phosphate than for laminarin and scleroglucan. Clearance was lower for glucan phosphate (42+/-6 ml/kg h) than for laminarin (103+/-17 ml/kg h) and scleroglucan (117+/-19 ml/kg h). Since plasma levels at steady state are inversely related to clearance, these differences suggest that pharmacokinetics could favor higher blood levels of glucans with certain physicochemical properties.


Asunto(s)
beta-Glucanos/farmacocinética , Animales , Área Bajo la Curva , Glucanos/administración & dosificación , Glucanos/química , Glucanos/farmacocinética , Semivida , Inyecciones Intravenosas , Prueba de Limulus , Modelos Lineales , Masculino , Polisacáridos/administración & dosificación , Polisacáridos/química , Polisacáridos/farmacocinética , Ratas , Ratas Sprague-Dawley , beta-Glucanos/administración & dosificación , beta-Glucanos/química
12.
J Pharmacol Exp Ther ; 314(3): 1079-86, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15976018

RESUMEN

Glucans are immunomodulatory carbohydrates found in the cell walls of fungi and certain bacteria. We examined the pharmacokinetics of three water-soluble glucans (glucan phosphate, laminarin, and scleroglucan) after oral administration of 1 mg/kg doses in rats. Maximum plasma concentrations for glucan phosphate occurred at 4 h. In contrast, laminarin and scleroglucan showed two plasma peaks between 0.5 and 12 h. At 24 h, 27 +/- 3% of the glucan phosphate and 20 +/- 7% of the laminarin remained in the serum. Scleroglucan was rapidly absorbed and eliminated. The liver did not significantly contribute to the clearance of plasma glucan. Biological effects were further studied in mice. Following oral administration of 1 mg, glucans were bound and internalized by intestinal epithelial cells and gut-associated lymphoid tissue (GALT) cells. Internalization of glucan by intestinal epithelial cells was not Dectin-dependent. GALT expression of Dectin-1 and toll-like receptor (TLR) 2, but not TLR4, increased following oral administration of glucan. Oral glucan increased systemic levels of interleukin (IL)-12 (151 +/- 15%) in mice. Oral glucan administration also increased survival in mice challenged with Staphylococcus aureus or Candida albicans. These data demonstrate that orally administered water-soluble glucans translocate from the gastrointestinal (GI) tract into the systemic circulation. The glucans are bound by GI epithelial and GALT cells, and they modulate the expression of pattern recognition receptors in the GALT, increase IL-12 expression, and induce protection against infectious challenge.


Asunto(s)
Glucanos/farmacología , Inmunidad Innata/efectos de los fármacos , Absorción Intestinal , Administración Oral , Animales , Disponibilidad Biológica , Candidiasis/inmunología , Citocinas/biosíntesis , Glucanos/administración & dosificación , Glucanos/farmacocinética , Lectinas Tipo C , Masculino , Proteínas de la Membrana/análisis , Proteínas de la Membrana/fisiología , Ratones , Ratones Endogámicos ICR , Proteínas del Tejido Nervioso/análisis , Proteínas del Tejido Nervioso/fisiología , Ganglios Linfáticos Agregados/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores Inmunológicos/análisis , Infecciones Estafilocócicas/inmunología , Receptor Toll-Like 2
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