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2.
BMC Cancer ; 23(1): 1070, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37932661

RESUMO

BACKGROUND: Colorectal cancer is a common malignant tumour. Invasive growth and distant metastasis are the main characteristics of its malignant biological behaviour, and they are also the primary factors leading to death in colon cancer patients. Atovaquone is an antimalarial drug, and its anticancer effect has recently been demonstrated in several cancer models in vitro and in vivo, but it has not been examined in the treatment of colorectal cancer. METHODS: To elucidate the effect of atovaquone on colorectal cancer. We used RNA transcriptome sequencing, RT‒PCR and Western blot experiments to examine the expression of NF-κB (p-P65), EMT-related proteins and related inflammatory factors (IL1B, IL6, CCL20, CCL2, CXCL8, CXCL6, IL6ST, FAS, IL10 and IL1A). The effect of atovaquone on colorectal cancer metastasis was validated using an animal model of lung metastases. We further used transcriptome sequencing, the GCBI bioinformatics database and the STRING database to predict relevant target proteins. Furthermore, pathological sections were collected from relevant cases for immunohistochemical verification. RESULTS: This study showed that atovaquone could inhibit colorectal cancer metastasis and invasion in vivo and in vitro, inhibit the expression of E-cadherin protein, and promote the protein expression of N-cadherin, vimentin, ZEB1, Snail and Slug. Atovaquone could inhibit EMT by inhibiting NF-κB (p-P65) and related inflammatory factors. Further bioinformatics analysis and verification showed that PDGFRß was one of the targets of atovaquone. CONCLUSION: In summary, atovaquone can inhibit the expression of NF-κB (p-P65) and related inflammatory factors by inhibiting the protein expression of p-PDGFRß, thereby inhibiting colorectal cancer metastasis. Atovaquone may be a promising drug for the treatment of colorectal cancer metastasis.


Assuntos
Neoplasias Colorretais , NF-kappa B , Animais , Humanos , NF-kappa B/metabolismo , Atovaquona/farmacologia , Atovaquona/uso terapêutico , Linhagem Celular Tumoral , Transdução de Sinais , Neoplasias Colorretais/patologia , Transição Epitelial-Mesenquimal , Movimento Celular
3.
Langenbecks Arch Surg ; 408(1): 186, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37160767

RESUMO

PURPOSE: Anastomotic leakage (AL) is one of the severe complications after rectal surgery, and anastomotic ischemia is one of the main factors. This prospective in vivo pilot study aimed to evaluate the effectiveness of Sidestream Dark Field (SDF) imaging in quantitative assessment of anastomotic microcirculation and to analyze its correlation with AL. METHODS: Thirty-three patients with rectal cancer who underwent laparoscopic low anterior resection from 2019 to 2020 were enrolled. Microcirculation was measured by SDF imaging at the descending colon, the mesocolon transection line (MTL), and 1 cm and 2 cm distal to the MTL. Anastomotic microcirculation was measured at the stapler anvil edge before anastomosis. Quantitative perfusion-related parameters were as follows: microcirculation flow index (MFI), perfused vessel density (PVD), proportion of perfused vessels (PPV), and total vessel density (TVD). RESULTS: All patients obtained stable microcirculation images. Functional microcirculation parameters (MFI, PPV, PVD) decreased successively from the descending colon, the colon at MTL, and 1 cm and 2 cm distal to the MTL (all P < 0.01). Extremely poor microcirculation was found at the intestinal segment 2 cm distal to the MTL. Micro-perfusion was significantly lower at the colonic limb of the anastomosis compared with the descending colon (all P < 0.001). Anastomotic leakage occurred in 3 patients (9.1%) whose anastomotic microcirculation was significantly lower than those without AL (all P < 0.01). Blood perfusion at the colonic limb of the anastomosis was significantly higher in patients with left colic artery preservation than in controls. CONCLUSION: SDF imaging is a promising technique for evaluating anastomotic microcirculation and has potential clinical significance for risk stratification of AL.


Assuntos
Fístula Anastomótica , Protectomia , Humanos , Projetos Piloto , Fístula Anastomótica/diagnóstico por imagem , Estudos Prospectivos , Anastomose Cirúrgica
4.
Biol Reprod ; 108(6): 887-901, 2023 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-37040346

RESUMO

The mule is the interspecific hybrid of horse and donkey and has hybrid vigor in muscular endurance, disease resistance, and longevity over its parents. Here, we examined adult fibroblasts of mule (MAFs) compared with the cells from their parents (donkey adult fibroblasts and horse adult fibroblasts) (each species has repeated three independent individuals) in proliferation, apoptosis, and glycolysis and found significant differences. We subsequently derived mule, donkey, and horse doxycycline (Dox)-independent induced pluripotent stem cells (miPSCs, diPSCs, and hiPSCs) from three independent individuals of each species and found that the reprogramming efficiency of MAFs was significantly higher than that of cells of donkey and horse. miPSCs, diPSCs, and hiPSCs all expressed the high levels of crucial endogenous pluripotency genes such as POU class 5 homeobox 1 (POU5F1, OCT4), SRY-box 2 (SOX2), and Nanog homeobox (NANOG) and propagated robustly in single-cell passaging. miPSCs exhibited faster proliferation and higher pluripotency and differentiation than diPSCs and hiPSCs, which were reflected in co-cultures and separate-cultures, teratoma formation, and chimera contribution. The establishment of miPSCs provides a unique research material for the investigation of "heterosis" and perhaps is more significant to study hybrid gamete formation.


Assuntos
Células-Tronco Pluripotentes Induzidas , Cavalos , Animais , Reprogramação Celular , Equidae , Células Cultivadas , Diferenciação Celular/genética , Fibroblastos , Fator 3 de Transcrição de Octâmero/genética
7.
Front Med (Lausanne) ; 8: 748493, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34926497

RESUMO

Objective: To evaluate the predictive value of electrical impedance tomography (EIT) in patients with delayed ventilator withdrawal after upper abdominal surgery. Methods: We retrospectively analyzed data of patients who were ventilated >24 h after upper abdominal surgery between January 2018 and August 2019. The patients were divided into successful (group S) and failed (group F) weaning groups. EIT recordings were obtained at 0, 5, 15, and 30 min of spontaneous breathing trials (SBTs) with SBT at 0 min set as baseline. We assessed the change in delta end-expiratory lung impedance and tidal volume ratio (ΔEELI/VT) from baseline, the change in compliance change percentage variation (|Δ(CW-CL)|) from baseline, the standard deviation of regional ventilation delay index (RVDSD), and global inhomogeneity (GI) using generalized estimation equation analyses. Receiver operating characteristic curve analyses were performed to evaluate the predictive value of parameters indicating weaning success. Results: Among the 32 included patients, ventilation weaning was successful in 23 patients but failed in nine. Generalized estimation equation analysis showed that compared with group F, the ΔEELI/VT was lower, and the GI, RVDSD, and (|Δ(CW-CL)|) were higher in group S. For predicting withdrawal failure, the areas under the curve of the ΔEELI/VT, (|Δ(CW-CL)|), and the RVDSD were 0.819, 0.918, and 0.918, and 0.816, 0.884, and 0.918 at 15 and 30 min during the SBTs, respectively. Conclusion: The electrical impedance tomography may predict the success rate of ventilator weaning in patients with delayed ventilator withdrawal after upper abdominal surgery.

8.
Proc Natl Acad Sci U S A ; 118(15)2021 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-33833056

RESUMO

Embryonic stem cells (ESCs) and induced pluripotent stem cells have the potential to differentiate to all cell types of an adult individual and are useful for studying development and for translational research. However, extrapolation of mouse and human ESC knowledge to deriving stable ESC lines of domestic ungulates and large livestock species has been challenging. In contrast to ESCs that are usually established from the blastocyst, mouse expanded potential stem cells (EPSCs) are derived from four-cell and eight-cell embryos. We have recently used the EPSC approach and established stem cells from porcine and human preimplantation embryos. EPSCs are molecularly similar across species and have broader developmental potential to generate embryonic and extraembryonic cell lineages. We further explore the EPSC technology for mammalian species refractory to the standard ESC approaches and report here the successful establishment of bovine EPSCs (bEPSCs) from preimplantation embryos of both wild-type and somatic cell nuclear transfer. bEPSCs express high levels of pluripotency genes, propagate robustly in feeder-free culture, and are genetically stable in long-term culture. bEPSCs have enriched transcriptomic features of early preimplantation embryos and differentiate in vitro to cells of the three somatic germ layers and, in chimeras, contribute to both the embryonic (fetal) and extraembryonic cell lineages. Importantly, precise gene editing is efficiently achieved in bEPSCs, and genetically modified bEPSCs can be used as donors in somatic cell nuclear transfer. bEPSCs therefore hold the potential to substantially advance biotechnology and agriculture.


Assuntos
Bovinos/genética , Células-Tronco Embrionárias/citologia , Técnicas de Transferência Nuclear/veterinária , Cultura Primária de Células/métodos , Animais , Blastocisto/citologia , Linhagem da Célula , Células Cultivadas , Células-Tronco Embrionárias/metabolismo , Cultura Primária de Células/veterinária , Transcriptoma
9.
Transl Cancer Res ; 9(4): 2259-2266, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35117586

RESUMO

BACKGROUND: In countries in East Asia, the typical treatment for curable gastric cancer is gastrectomy with D2 lymphadenectomy. However, whether D2 lymphadenectomy is beneficial for high-risk N3 node disease remains controversial. We conducted a multi-institution retrospective study on patients with high-risk, locally advanced gastric cancer. To compare the rates of disease-free survival (DFS) and overall survival (OS) between radical D2-type gastric resection and lymphadenectomy and the more limited D1 type resection and lymphadenectomy. METHODS: From July 2010 to June 2015, 74 patients out of 949 who underwent curative-intent R0 surgery were selected in pairs to compare the survival outcomes between those who underwent radical D2 type (n=37) vs. the more limited D1 type (n=37) gastric resection and lymphadenectomy. RESULTS: The median DFS was 9.72 and 7.81 months for the D2 and D1 types, respectively (P=0.746), and the OS was 16.39 and 15.85 months for the D2 and D1 types, respectively (P=0.937). CONCLUSIONS: No statistically significant differences in DFS and OS were noted between D1 and D2 procedures for those with N3 disease. Our results support the hypothesis that a novel multidisciplinary approach rather than a surgical approach alone is needed to improve the survival outcomes of high-risk patients with N3 gastric cancer.

10.
Gastroenterol Res Pract ; 2019: 1750329, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30838039

RESUMO

BACKGROUND: Circulating tumor DNA (ctDNA) derived from tumors is a promising biomarker for monitoring tumor status and evaluating therapeutic effects and prognosis. We studied the plasma human epidermal growth factor receptor 2 (HER2) amplification in gastric cancer (GC) patients by droplet digital PCR (ddPCR) during therapy with trastuzumab. METHODS: A total of 12 patients were recruited after surgery. All patients received FOLFOX chemotherapy combined with trastuzumab as a treatment regimen. During the 12 months of the follow-up period, using elongation factor Tu GTP binding domain containing 2 (EFTUD2) as a reference gene, plasma HER2 to EFTUD2 ratios (the HER2 ratio) were determined for each patient every 2 months by ddPCR. RESULTS: The concordance rate of HER2 amplification examined in plasma and formalin-fixed paraffin-embedded (FFPE) samples with ddPCR was 81.4%, with a sensitivity of 76.5% and a specificity of 83.8%. Plasma HER2 ratios were correlated with the primary tumor size (p < 0.01). A significant decrease in the plasma HER2 ratio was found after two months of treatment (p < 0.0001). Nine patients experienced partial response, and three patients had stable disease. Seven patients had progressive disease (PD) during follow-up, and four of them had died. The median progression-free survival (PFS) was 9.8 months. For each patient who developed PD, the plasma HER2 ratio was approximately 2.3-4.1 times higher than the cut-off value at the time of PD, which was the highest during the whole follow-up period. CONCLUSION: Longitudinal monitoring for the plasma HER2 ratio by ddPCR in the clinical courses of GC patients holds great promise for use as an indicator of tumor progression and treatment efficacy.

11.
BMC Cancer ; 18(1): 676, 2018 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-29929476

RESUMO

BACKGROUND: Novel non-invasive biomarkers for gastric cancer (GC) are needed, because the present diagnostic methods for GC are either invasive or insensitive and non-specific in clinic. The presence of stable circulating microRNAs (miRNAs) in plasma suggested a promising role as GC biomarkers. METHODS: Based on the quantitative droplet digital PCR (ddPCR), four miRNAs (miR-21, miR-93, miR-106a and miR-106b) related to the presence of GC were identified in plasma from a training cohort of 147 participants and a validation cohort of 28 participants. RESULTS: All circulating miRNA levels were significantly higher in the plasma of GC patients compared to healthy controls (P < 0.05). Through a combination of four miRNAs by logistic regression model, receiver operating characteristic (ROC) analyses yielded the highest AUC value of 0.887 in discriminating GC patients from healthy volunteers. Furthermore, miR-21, miR-93 and miR-106b levels were significantly related to an advanced TNM stage in GC patients. ROC analyses of the combined miRNA panel also showed the highest AUC value of 0.809 in discriminating GC patients with TNM stage I and II from stage III and IV. Through combining four miRNAs and clinical parameters, a classical random forest model was established in the training stage. In the validation cohort, it correctly discriminated 23 out of 28 samples in the blinded phase (false rate, 17.8%). CONCLUSIONS: Using the ddPCR technique, circulating miR-21, miR-93, miR-106a and miR-106b could be used as diagnostic plasma biomarkers in gastric cancer patients.


Assuntos
Biomarcadores Tumorais/sangue , MicroRNA Circulante/sangue , Reação em Cadeia da Polimerase/métodos , Neoplasias Gástricas/diagnóstico , Adulto , Idoso , Área Sob a Curva , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Sensibilidade e Especificidade , Neoplasias Gástricas/sangue
12.
J Cell Biochem ; 119(8): 7091-7104, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29738066

RESUMO

Emerging evidence has identified that long non-coding RNAs (lncRNAs) may play an important role in the pathogenesis of many cancer types, including colorectal cancer (CRC). However, the role of PlncRNA-1 in CRC remains unclear. The aim of our present study was to investigate the potential functions of PlncRNA-1 in CRC and to identify the underlying mechanisms of action. We demonstrated that up-regulated PlncRNA-1 in CRC tissues and cells promoted cell proliferation by accelerating cell cycle process and inhibiting cell apoptosis in vitro, enhanced tumor growth and matastasis in vivo and was associated with cell migration and invasion, EMT process of CRC cells. In addition, PlncRNA-1 was a target of miR-204 and enhanced the expression of an endogenous miR-204 target, MMP9 in CRC cells. Furthermore, we found that PlncRNA-1 activates Wnt/ß-catenin pathway through the miR-204 in CRC cells. These results suggest that the PlncRNA-1/miR-204/ Wnt/ß-catenin regulatory network may shed light on tumorigenesis in CRC.


Assuntos
Proliferação de Células , Neoplasias Colorretais/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/secundário , RNA Longo não Codificante/metabolismo , RNA Neoplásico/metabolismo , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Feminino , Células HCT116 , Humanos , Neoplasias Hepáticas/genética , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Metástase Neoplásica , RNA Longo não Codificante/genética , RNA Neoplásico/genética , Via de Sinalização Wnt
13.
Clin Exp Pharmacol Physiol ; 45(7): 729-741, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29542167

RESUMO

MicroRNA-21-3p (miR-21-3p), the passenger strand of pre-mir-21, has been found to be high-expressing in various cancers and to be associated with tumour malignancy, which is proposed as a novel focus in malignant tumours. Colorectal cancer (CRC), currently known as one of the most prevalent malignancy, is a leading cause of cancer death. This study aimed to investigate the key role of miR-21-3p in CRC by inhibiting its expression using transfection with miR-21-3p inhibitors into human CRC HCT116 cells. Results showed that the expression of miR-21-3p was higher than other CRC cells used in the study including Lovo, HT29, Colo320 and SW480 cells, inhibition of which suppressed the proliferation and induced cell cycle arrest in HCT116 cells. Besides, transfection with miR-21-3p inhibitors also attenuated cell migration and invasion, and induced apoptosis as well. Moreover, luciferase assay confirmed RBPMS as a direct target of miR-21-3p in HCT116 cells. Further, miR-21-3p inhibitors increased the nuclear accumulation of Smad4 and reduced phosphorylation of ERK. Interestingly, we found that silence of RBPMS using RNA interference (siRNA) not only elevated the cell viability but also increased the phosphorylation of ERK and reversed the nuclear accumulation of Smad4 induced by miR-21-3p inhibitors in HCT116 cells. Data suggest that inhibition of miR-21-3p suppresses cell proliferation, invasion as well as migration and induces apoptosis by directly targeting RBPMS through Smad4/ERK signalling pathway in HCT116 cells. Our study demonstrates miR-21-3p as a potent target for suppressing tumour progression of CRC which may have implications in CRC therapy in the future.


Assuntos
Apoptose/genética , Neoplasias Colorretais/patologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Sistema de Sinalização das MAP Quinases/genética , MicroRNAs/genética , Proteínas de Ligação a RNA/genética , Proteína Smad4/metabolismo , Movimento Celular/genética , Proliferação de Células/genética , Células HCT116 , Humanos , Invasividade Neoplásica
14.
BMC Gastroenterol ; 17(1): 167, 2017 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-29262780

RESUMO

BACKGROUND: Extramedullary plasmacytoma is a very rare tumor derived from plasma cells and found outside the bone marrow. Most have been identified in patients with the more aggressive anaplastic form of the disease. Only a few cases of primary pancreatic plasmacytoma have been reported. CASE PRESENTATION: We present a case of a 56-year-old man in whom a pancreatic mass was found incidentally. The lesion was determined to be a pancreatic plasmacytoma after distal pancreatectomy. There are no indications of clinical, laboratory or imaging findings of multiple myeloma nor any association with plasmacytoma in any other places, so the diagnosis of primary pancreatic plasmacytoma was made. CONCLUSION: Primary pancreatic plasmacytoma is rare and the diagnosis is difficult before surgery.


Assuntos
Neoplasias Pancreáticas/diagnóstico , Plasmocitoma/diagnóstico , Biomarcadores Tumorais/sangue , Humanos , Imuno-Histoquímica , Achados Incidentais , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Pancreatectomia , Neoplasias Pancreáticas/cirurgia , Plasmocitoma/cirurgia
15.
Tissue Cell ; 49(5): 521-527, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28720304

RESUMO

Single-cell derived bovine induced pluripotent stem cells (iPSCs) were generated by the introduction of piggyBac transposons with CAG promoting transcription factors (Oct3/4, Sox2, Klf4 and cMyc). In the study, the bovine iPSCs colony from single cell could passage more than 50 passages after enzymatic dissociation into single cells. These bovine iPSCs cells kept the normal karyotype and displayed dome shaped clones similar to mouse embryonic stem cells. They showed pluripotency in many ways, including their expression of pluripotency markers, such as OCT3/4, NANOG, SOX2, SSEA1, SSEA4, and AP in immunofluorescence assay, Oct4, Nanog, Sox2, Klf4 and cMyc in RT-PCR. Additionally, single-cell derived bovine iPSCs formed embryoid bodies and teratomas that all subsequently gave rise to differentiated cells from all three embryonic germ layers. The results showed that our reprogramming method could obtain high efficiency single-cell cloning bovine iPSCs, and the efficiency of single cell cloning is 40%.


Assuntos
Células-Tronco Pluripotentes Induzidas/citologia , Animais , Bovinos , Técnicas de Cultura de Células , Células Cultivadas , Fator 4 Semelhante a Kruppel
16.
Pak J Med Sci ; 31(3): 572-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26150846

RESUMO

OBJECTIVE: To compare the therapeutic effects of laparotomy and laparoscopic surgery on patients with gastric cancer. METHODS: Sixty-six patients with gastric cancer who were treated in our hospital from January 2012 to December 2013 were selected and divided into a control group and an observation group by the random number method (n=33). The control group was treated by traditional laparotomy, and the observation group was treated by laparoscopic surgery. CD4/CD8 ratios and IgG expressions in the patients were detected on preoperative and postoperative fourth days. Intraoperative blood loss, surgical time, time of anal gas evacuation and time of postoperative independent ambulation of the two groups were observed. RESULTS: The intraoperative blood loss, surgical time, time of anal gas evacuation, time of postoperative independent ambulation, time of urinary catheter indwelling and average hospitalization stay length of the observation group were significantly different from those of the control group (P<0.05). The postoperative rates of fever and complications in the observation group were significantly lower than those of the control group, and the two groups had significantly different CD4/CD8 ratios and IgG levels on the postoperative 4th day (P<0.05). CONCLUSION: Compared with traditional laparotomy, laparoscopic surgery can well treat patients with gastric cancer minimally invasively. Meanwhile, their postoperative recovery was facilitated due to slightly affected humoral immunity and cellular immune function.

17.
Eur J Immunol ; 44(6): 1728-36, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24700192

RESUMO

Regulatory B (Breg) cells have been shown to play a critical role in immune homeostasis and in autoimmunity models. We have recently demonstrated that combined anti-T cell immunoglobulin domain and mucin domain-1 and anti-CD45RB antibody treatment results in tolerance to full MHC-mismatched islet allografts in mice by generating Breg cells that are necessary for tolerance. Breg cells are antigen-specific and are capable of transferring tolerance to untreated, transplanted animals. Here, we demonstrate that adoptively transferred Breg cells require the presence of regulatory T (Treg) cells to establish tolerance, and that adoptive transfer of Breg cells increases the number of Treg cells. Interaction with Breg cells in vivo induces significantly more Foxp3 expression in CD4(+) CD25(-) T cells than with naive B cells. We also show that Breg cells express the TGF-ß associated latency-associated peptide and that Breg-cell mediated graft prolongation post-adoptive transfer is abrogated by neutralization of TGF-ß activity. Breg cells, like Treg cells, demonstrate preferential expression of both C-C chemokine receptor 6 and CXCR3. Collectively, these findings suggest that in this model of antibody-induced transplantation tolerance, Breg cells promote graft survival by promoting Treg-cell development, possibly via TGF-ß production.


Assuntos
Subpopulações de Linfócitos B/imunologia , Sobrevivência de Enxerto/imunologia , Transplante das Ilhotas Pancreáticas/imunologia , Linfócitos T Reguladores/imunologia , Fator de Crescimento Transformador beta/imunologia , Tolerância ao Transplante , Transferência Adotiva , Aloenxertos , Animais , Subpopulações de Linfócitos B/patologia , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/imunologia , Regulação da Expressão Gênica/genética , Regulação da Expressão Gênica/imunologia , Sobrevivência de Enxerto/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Receptores CCR6/genética , Receptores CCR6/imunologia , Receptores CXCR3/genética , Receptores CXCR3/imunologia , Linfócitos T Reguladores/patologia , Fator de Crescimento Transformador beta/genética
18.
Sci Transl Med ; 3(87): 87ra52, 2011 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-21677198

RESUMO

The senescent immune system responds poorly to new stimuli; thymic involution, accumulation of memory cells against other specificities, and general refractoriness to antigen signaling all may contribute to poor resistance to infection. These same changes may pose a significant clinical barrier to organ transplantation, as transplantation tolerance requires thymic participation and integrated, tolerance-promoting responses to novel antigens. We found that after the age of 12 months, mice became resistant to the tolerance-inducing capacity of the monoclonal antibody therapy anti-CD45RB. This resistance to tolerance to cardiac allografts could be overcome by surgical castration of male mice, a procedure that led to thymic regeneration and long-term graft acceptance. The potential for clinical translation of this endocrine-immune interplay was confirmed by the ability of Lupron Depot injections, which temporarily disrupt gonadal function, to restore tolerance in aged mice. Furthermore, we demonstrated that the restoration of tolerance after surgical or chemical castration depended on thymic production of regulatory T cells (T(regs)); thymectomy or T(reg) depletion abrogated tolerance restoration. The aging of the immune system ("immune senescence") is a significant barrier to immune tolerance, but this barrier can be overcome by targeting sex steroid production with commonly used clinical therapeutics.


Assuntos
Envelhecimento/imunologia , Sistema Endócrino/fisiologia , Sistema Imunitário/fisiologia , Tolerância ao Transplante/imunologia , Animais , Antineoplásicos Hormonais/farmacologia , Castração , Gônadas/efeitos dos fármacos , Gônadas/fisiologia , Transplante de Coração/imunologia , Humanos , Antígenos Comuns de Leucócito/imunologia , Leuprolida/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Timectomia , Timo/citologia , Timo/efeitos dos fármacos , Transplante Homólogo/imunologia
19.
Theriogenology ; 76(4): 700-4, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21601263

RESUMO

Three media were evaluated for their ability to support in vitro maturation of donkey (Equus asinus) oocytes and their development after parthenogenetic activation. The basal medium for Medium 1 (M1) and Medium 2 (M2) was M199 and DMEM/F12 respectively, whereas, Medium 3 (M3) consisted of equal parts (v/v) of M199 and DMEM/F12. All three media were supplemented with 10% (v/v) fetal calf serum, 0.01 units/mL porcine FSH, 0.01 units/mL equine LH, 200 ng/mL insulin-like growth factor 1(IGF-I), 10 µl/mL insulin-transferrin-selenium (ITS), 0.1 mg/mL taurine, 0.1 mg/mL L-cysteine, 0.05 mg/mL L-glutamine, 0.11 mg/mL sodium pyruvate, and 25 mg/mL gentamycin. There were no significant differences among the three maturation media for oocyte maturation. Maturation rate of donkey oocytes in M1 was 53% for compact (Cp) cumulus-oocyte complexes and 75% for expanded (Ex) cumulus-oocyte complexes; in M2 these were 55 and 77%, respectively; and in M3, 58 and 75%. The percentage of cleaved parthenotes and 4- or 8-cell embryos were not significantly different for oocytes matured in the various media (61 and 24% for M1; 66 and 32% for M2; and 67 and 33% for M3). Oocytes matured in M3 tended to yield a higher rate of advanced embryo development (morula) than oocytes matured in M1 (22 vs 9%; P = 0.07). In conclusion, donkey oocytes were matured and parthenogenetically activated in vitro, using methods similar to those used in the horse.


Assuntos
Equidae/fisiologia , Oócitos/fisiologia , Animais , Técnicas de Cultura de Células , Distribuição de Qui-Quadrado , Meios de Cultura , Feminino , Oócitos/citologia , Partenogênese/fisiologia
20.
Transplantation ; 91(7): 707-13, 2011 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-21386770

RESUMO

BACKGROUND: Because CD4CD25Foxp3 regulatory T cells (Tregs) are essential for the maintenance of self-tolerance, significant interest surrounds the developmental cues for thymic-derived natural Tregs (nTregs) and periphery-generated adaptive Tregs (aTregs). In the transplant setting, the allograft may play a role in the generation of alloantigen-specific Tregs, but this role remains undefined. We examined whether the immune response to a transplant allograft results in the peripheral generation of aTregs. METHODS: To identify generation of aTregs, purified graft-reactive CD4CD25 T cells were adoptively transferred to mice-bearing skin allograft. To demonstrate that aTregs are necessary for tolerance, DBA/2 skin was transplanted onto C57BL/6-RAG-1-deficient recipients adoptively transferred with purified sorted CD4CD25 T cells; half of the recipients undergo tolerance induction treatment. RESULTS: By tracking adoptively transferred cells, we show that purified graft-reactive CD4CD25 T lymphocytes up-regulate Foxp3 in mice receiving skin allografts in the absence of any treatment. Interestingly, cotransfer of antigen-specific nTregs suppresses the up-regulation of Foxp3 by inhibiting the proliferation of allograft-responsive T cells. In vitro data are consistent with our in vivo data-Foxp3 cells are generated on antigen activation, and this generation is suppressed on coculture with antigen-specific nTregs. Finally, blocking aTreg generation in grafted, rapamycin-treated mice disrupts alloantigen-specific tolerance induction. In contrast, blocking aTreg generation in grafted mice treated with nondepleting anti-CD4 plus anti-CD40L antibodies does not disrupt graft tolerance. CONCLUSIONS: We conclude that graft alloantigen stimulates the de novo generation of aTregs, and this generation may represent a necessary step in some but not all protocols of tolerance induction.


Assuntos
Isoantígenos/imunologia , Linfócitos T Reguladores/fisiologia , Tolerância ao Transplante , Animais , Antígenos CD40/fisiologia , Ligante de CD40/fisiologia , Fatores de Transcrição Forkhead/genética , Interleucina-2/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Sirolimo/farmacologia , Fator de Crescimento Transformador beta/farmacologia , Transplante Homólogo
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