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1.
Transplant Proc ; 51(2): 405-407, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30879552

RESUMEN

PURPOSE: The program Old for Old or European Senior Program (ESP), allocates donors aged ≥65 years to recipients of ≥65, within a narrow geographic area in order to minimize cold ischemia time, decrease the waiting time for elderly patients listed for kidney transplantation and expand the transplant resource in this group. The ESP is not officially applied in Greece. In our center, the Old for Old criteria have been used since 2003 for elderly patients who are candidates for kidney transplantation. METHODS: We aimed to retrospectively evaluate the results of kidney transplantation from donors ≥65 years to recipients ≥65 years (Old for Old group), by examining a 5-year actual survival of the recipient and the graft. Ten Old for Old transplantations were performed at our center and the graft and patient survival was estimated during a 5-year follow-up. This group was compared to a control group of 10 recipients under the age of 65, who received grafts from deceased donors aged ≥65 years; it was found that graft and patient survival was significantly lower in the Old for Old group (50% and 58% respectively), compared to the control group, with graft and patient survival 72% and 80%, respectively (P < .05). The main cause of death was cardiovascular disease. CONCLUSIONS: More studies with higher number of patients are needed for the assessment of survival outcome between the elderly transplanted patient and those on dialysis listed for renal allografts to conclude whether Old for Old transplantation is beneficial. It is also important to consider a better pre-transplant medical evaluation with attention to cardiovascular status of the candidates and modification of the immunosuppression protocol in order to avoid serious infections and long hospital stays.


Asunto(s)
Supervivencia de Injerto , Trasplante de Riñón/mortalidad , Trasplante de Riñón/métodos , Donantes de Tejidos/provisión & distribución , Anciano , Femenino , Grecia , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
2.
Transplant Proc ; 51(2): 408-412, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30879553

RESUMEN

PURPOSE: We investigated the association of ureteral stenting after kidney transplantation with the development of urinary tract infections (UTIs) and/or urinary tract colonization, in a hospital environment considered endemic for multidrug resistant (MDR) Gram-negative Enterobacteriaceae. METHODS: Seventy-five recipients of deceased donor grafts were divided in groups A and B. Group A (with subgroups A1 and A2) included 45 transplanted patients without urinary stenting, and group B 30 patients with stenting. Subgroup A1 consisted of 30 patients transplanted before 2006, and A2 of 15 patients transplanted after 2006, when MDR, mainly carbapenem-resistant, Enterobacteriaceae, frequency has risen in our hospital. RESULTS: The incidence and the number of UTIs per patient were significantly higher in patients without stenting compared to those with stenting. (Group A: 32/45 vs group B: 9/30, P < .001, and group A: 2.86 ± 0.43 vs group B: 0.6 ± 0.19, P < .01 respectively). Patients without stenting tended to have a higher frequency of recurrent UTIs compared to those with stenting (group A: 16/45 vs group B: 4/30, P < .05). Asymptomatic bacteriuria was more frequent in the patients with stent (group A: 8/45 vs group B: 14/30, P < .05). Further sub-comparison of the A1 and A2 subgroups with group B did not change the statistical results. CONCLUSIONS: There is no clinically significant association of ureteral stenting after kidney transplantation with the high frequency of MDR Gram-negative bacteria in our hospital.


Asunto(s)
Infección Hospitalaria/epidemiología , Infecciones por Enterobacteriaceae/epidemiología , Trasplante de Riñón/métodos , Infecciones Urinarias/epidemiología , Adulto , Anciano , Farmacorresistencia Bacteriana Múltiple , Enterobacteriaceae , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Stents , Uréter/cirugía
3.
Transplant Proc ; 51(2): 413-415, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30879554

RESUMEN

PURPOSE: De novo donor-specific antibodies (DSA) are associated with antibody-mediated rejection leading to late renal transplant failure. The aim of this study was to evaluate whether HLA compatibility is associated with sensitization along with other risk factors. METHODS: Eighty-nine stable renal transplant recipients (47 men) were studied. Patients were classified into 2 groups according to HLA compatibility between donor and recipient, group A (1-4/8 matches) and group B (5-8/8 matches). Cold ischemia time (CIT) and delayed graft function (DGF) were recorded along with time with a functional graft. Anti-HLA antibodies were detected using a Luminex single-antigen bead assay and were further classified into DSA and non-DSA. RESULTS: HLA group A consisted of 49 (56%) transplant recipients while 38 (44%) were classified to group B, with functional grafts for 10.9 ± 6.7 and 14.8 ± 8.5 years, respectively (P = .019). Group A patients had more anti-HLA antibodies than group Β (P = .001) and this correlation was retained for DSA patients. De novo anti-HLA were detected in 40 patients; DSA were detected in 19 (21.8%). DSA (+) patients had recorded with functional renal grafts for 11 ± 5 years, compared to 14.4 ± 8.6 years (P = .048) for anti-HLA negative patients. Increased CIT and DGF were associated with anti-HLA antibodies detection but no with DSA. CONCLUSION: HLA compatibility is probably correlated with DSA in a context of a more general anti-HLA sensitization, and both have a negative effect on long-term renal graft outcome.


Asunto(s)
Rechazo de Injerto/inmunología , Antígenos HLA/inmunología , Histocompatibilidad/inmunología , Isoanticuerpos/inmunología , Trasplante de Riñón , Adulto , Femenino , Supervivencia de Injerto/inmunología , Humanos , Masculino , Persona de Mediana Edad , Donantes de Tejidos
4.
Transplant Proc ; 51(2): 424-428, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30879557

RESUMEN

INTRODUCTION: The prevalence and impact of pre-existing and de novo anti-HLA donor-specific antibodies (DSAs) after orthotopic liver transplantation (OLT) is still controversial. We investigated the prevalence of DSAs and their implication in the development of allograft dysfunction after OLT. PATIENTS AND METHODS: A total of 65 liver transplant patients were tested for anti-HLA antibodies, with single antigen bead technology, before, 1, 3, 6, and 12 months after transplantation, and thereafter annually, along with other risk factors. Sixteen out of 65 patients (24.6%) had circulating pre-existing anti-HLA antibodies, and 4 of them (25%) had DSAs. All patients positive for anti-HLA antibodies (100%) presented allograft dysfunction. Fourteen out of 65 patients (21.5%) had circulating de novo DSAs, and 12 out of 14 (85.7%) presented allograft dysfunction. The investigated risk factors for allograft dysfunction were: recipient and donor age, time on the waiting list, cold ischemia time, cytomegalovirus infection, immunosuppression regimen, de novo DSAs, Model for End-Stage Liver Disease, aspartate aminotransferase, alanine aminotransferase, gamma-glutamyl transpeptidase (GGT), direct bilirubin and total bilirubin peak post-transplant, and alkaline phosphatase. The multivariate analysis showed that de novo DSAs and time on the waiting list were independent risk factors for allograft dysfunction. CONCLUSION: Our results show that de novo DSAs are an independent risk factor for allograft dysfunction, along with time on the waiting list.


Asunto(s)
Rechazo de Injerto/inmunología , Supervivencia de Injerto/inmunología , Antígenos HLA/inmunología , Isoanticuerpos/inmunología , Trasplante de Hígado , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Donantes de Tejidos
5.
Transplant Proc ; 51(2): 454-456, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30879565

RESUMEN

BACKGROUND: Infections due to extensively drug resistant Gram-negative bacteria (GNB) after solid organ transplantation are increasing in prevalence and are associated with high morbidity and mortality. Surveillance culture (SC) seems to be an important tool for extensively drug resistant GNB control. The aim of this study was to evaluate colonization rates and subsequent infections by XDR-GNB in liver transplant recipients. MATERIAL AND METHODS: This was a prospective cohort study in patients who underwent liver transplantation (LT) between January 2016 and January 2018. Data on demographics, extensively drug resistant colonization, and 3-month clinical outcomes were obtained. Colonization was defined as a positive surveillance culture (SC-perirectal) immediately before transplantation, once weekly after LT, and after intensive care unit discharge, with emphasis to carbapenem-resistant Gram-negative bacteria (CR-GNB). RESULTS: Forty-four patients who underwent LT were included in the study. Ten patients (22.72%) were colonized with CR-GNB prior to transplantation, and 7/10 (70%) developed infection due to the same pathogen (5 patients bloodstream infections, 2 patients pneumonia) during the study period. Intensive care unit length of stay was significantly longer in colonized with CR-GNB patients (P < .05). Mortality rate was higher in colonized patients (30%) than in noncolonized (11.76%) (P = .2). CONCLUSION: Our study results suggest an overall 70% risk of CR-GNB infection among colonized patients. Given the high mortality rate and the difficulty in treating these infections, further research to investigate and develop strategies to eliminate the colonization is needed.


Asunto(s)
Infecciones por Bacterias Gramnegativas/epidemiología , Infecciones por Bacterias Gramnegativas/inmunología , Huésped Inmunocomprometido , Trasplante de Hígado , Adulto , Anciano , Farmacorresistencia Bacteriana , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , Factores de Riesgo
6.
Transplant Proc ; 51(2): 457-460, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30879566

RESUMEN

INTRODUCTION: The importance of preoperative donor/recipient colonization or donor infection by extensively drug-resistant Gram-negative bacteria (XDR-GNB) and its relation to serious post-transplantation infection pathogenicity in liver transplantation (LT) patients has not been clarified. AIM: Prevention of postoperative infection due to XDR-GNB with the appropriate perioperative chemoprophylaxis or treatment based on preoperative donor/recipient surveillance cultures in LT patients, as well as their outcome. MATERIALS AND METHOD: Twenty-six patients (20 male, 6 female) were studied (average preoperative Model for End-Stage Liver Disease score ≈15, range: 8-29) from January 2017 to January 2018. In all patients, blood, urine, and bronchial secretions culture samples as well as a rectal colonization culture were taken pre- and postoperatively, once weekly after LT, and after intensive care unit discharge. Recipients with positive XDR-GNB colonization and patients receiving a transplant from a donor with an XDR-GNB positive culture or colonization received the appropriate chemoprophylaxis one half hour preoperatively according to culture results. De-escalation of the antibiotic regimen was done in 2 to 5 days based on the colonization/culture results of the donor and recipient and their clinical condition. Evaluation for serious infection was done at 1 week and at 28 days for outcome results. RESULTS: Fourteen out of 26 recipients (53.8%) were positive for XDR-GNB colonization preoperative, with 2/14 (14.28%) presenting serious infection due to the same pathogen. Intensive care unit length of stay was significantly longer in colonized with XDR-GNB patients (P < .0001). The outcome of colonized patients was 6/14 (42.8%) expired, but only in 2/14 (14.2%) was mortality attributable to infection. CONCLUSION: Administering appropriate perioperative chemoprophylaxis and treatment may limit the frequency of XDR-GNB infections and intensive care unit length of stay and may improve the outcome in LT recipients.


Asunto(s)
Profilaxis Antibiótica/métodos , Infecciones por Bacterias Gramnegativas/inmunología , Infecciones por Bacterias Gramnegativas/prevención & control , Huésped Inmunocomprometido , Trasplante de Hígado , Adulto , Antibacterianos/uso terapéutico , Femenino , Bacterias Gramnegativas , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Donantes de Tejidos
7.
Hippokratia ; 19(3): 249-55, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-27418785

RESUMEN

BACKGROUND: Liver regeneration is vital for the survival of patients submitted to extensive liver resection as a treatment of hepatocellular carcinoma (HCC). Sorafenib is a multikinase inhibitor of angiogenesis and cell division, both of which are integral components of liver regeneration. We investigated the effect of preoperative treatment with sorafenib, a drug used for the treatment of HCC, on liver regeneration and angiogenesis in healthy rats, after two-thirds partial hepatectomy (PH2/3). METHODS: In total 48 Wistar rats received intragastric injections of sorafenib (30 mg/kg/d) or vehicle, underwent PH2/3, and were sacrificed at 48, 96 or 168 hours after that. The regenerative index of the liver remnant was studied, as well as the mitotic index. DNA synthesis and angiogenesis were estimated by immunohistochemistry for the Ki-67 and CD34 antigens, respectively. RESULTS: Sorafenib reduced significantly the regenerative index at all time points but not the mitotic index at 48, 96 or 168 hours. Deoxyribonucleic acid (DNA) synthesis and angiogenesis were not affected significantly either. CONCLUSIONS: Sorafenib, when administered preoperatively, reduces incompletely and transiently the regeneration of the liver after PH2/3 in rats. This could mean that sorafenib can be used as neoadjuvant treatment of patients with HCC prior to liver resection, but further experimental and clinical studies are needed to establish the safety of this treatment. Hippokratia 2015; 19 (3): 249-255.

8.
Transplant Proc ; 44(9): 2712-4, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23146501

RESUMEN

AIM: The outcome of simultaneous pancreas-kidney transplantation (SPK) in type 1 diabetes has dramatically improved in recent years. We report the initial results of our SPK program. PATIENTS AND METHODS: From 2008 to 2010, we performed and prospectively obtained data on 4 SPKs in 4 type 1 diabetic patients with chronic renal failure. The recipients were 3 men and 1 woman, of overall mean age of 40.75 ± 4.78 years, mean time from diabetes diagnosis of 27 ± 15 years, and time on dialysis of 3.5 ± 0.57 years. All grafts were procured from multiorgan brain-dead donors of mean age 26 ± 8.16 years and mean body weight of 74 ± 4.34 kg. The pancreatic grafts were transplanted first into the right iliac fossa with mean cold ischemia times of 10.62 ± 3.09 hours for the pancreatic and 14.00 ± 2.97 hours for the renal grafts. Pancreas arterial inflow was re-established by an end-to-side anastomosis of an extension Y-graft to the recipient right iliac artery. The portal vein was sutured to the iliac vein directly. The exocrine secretions of the pancreas were managed by duodenojejunostomy extraperitoneally (n = 3) or intraperitoneally (n = 1). The ureteral anastomosis was performed using the Taguchi technique. RESULTS: After SPK, endocrine pancreatic function was immediately restored in all patients. Insulin administration was stopped within the first 24 hours after surgery. Two patients displayed delayed renal graft function necessitating dialysis for 9 and 23 days, respectively. The postoperative course was prolonged with a mean hospital stay of 82 ± 1 day. At a 31.75 ± 9.03 months follow up all patients are alive with functioning grafts. CONCLUSION: Our experience with SPK, although limited, has shown encouraging results over a short follow-up period.


Asunto(s)
Diabetes Mellitus Tipo 1/cirugía , Nefropatías Diabéticas/cirugía , Fallo Renal Crónico/cirugía , Trasplante de Riñón , Trasplante de Páncreas , Adolescente , Adulto , Funcionamiento Retardado del Injerto/etiología , Funcionamiento Retardado del Injerto/terapia , Diabetes Mellitus Tipo 1/complicaciones , Nefropatías Diabéticas/etiología , Femenino , Supervivencia de Injerto , Grecia , Humanos , Hipoglucemiantes/uso terapéutico , Insulina/uso terapéutico , Fallo Renal Crónico/etiología , Trasplante de Riñón/efectos adversos , Trasplante de Riñón/métodos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Tomografía Computarizada Multidetector , Trasplante de Páncreas/efectos adversos , Trasplante de Páncreas/métodos , Estudios Prospectivos , Diálisis Renal , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
9.
Transplant Proc ; 44(9): 2737-40, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23146509

RESUMEN

BACKGROUND: The importance of adhesion molecules for local invasion by neoplastic cells and development of metastasis has been confirmed by numerous studies over the past decade. Claudins are integral parts of tight junctions. The aim of the present study was to examine the significance of the expression of claudin-7 messenger RNA (mRNA) as a prognostic factor for hepatocellular carcinoma (HCC). PATIENTS AND METHODS: We examined liver tumor and nontumor tissues from 20 HCC patients who underwent resection or liver transplantation. RESULTS: A significant increase in the expression of claudin-7 was observed in tumor versus nontumor tissues. There was no significant correlation between the expression profile of claudin-7 mRNA and patient demographic data, the presence of cirrhosis, or the histological stage of tumor differentiation or vascular invasion. Survival analysis showed a trend toward a better prognosis among patients with overexpression of claudin-7 in tumor tissues.


Asunto(s)
Biomarcadores de Tumor/genética , Carcinoma Hepatocelular/genética , Claudinas/genética , Neoplasias Hepáticas/genética , Adulto , Anciano , Análisis de Varianza , Carcinoma Hepatocelular/mortalidad , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/cirugía , Distribución de Chi-Cuadrado , Femenino , Regulación Neoplásica de la Expresión Génica , Hepatectomía , Humanos , Estimación de Kaplan-Meier , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/cirugía , Trasplante de Hígado , Masculino , Persona de Mediana Edad , ARN Mensajero/análisis , Resultado del Tratamiento , Regulación hacia Arriba
10.
Transplant Proc ; 44(9): 2773-5, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23146520

RESUMEN

INTRODUCTION: Reactivation of hepatitis B virus (HBV) is a complication of immunosuppressive treatment in patients with a history of HBV exposure. CASE PRESENTATION: Herein we have reported a case of reactivation after renal transplantation in a 52-year-old male chronic HBV carrier who was treated with hepatitis B immunoglobulin (HBIg) prophylaxis immediately after transplantation in addition to cyclosporine, mycophenolate mofetil and prednisolone for maintenance immunosuppression. After application of rituximab, the patient developed clinical hepatitis with a high load of HBV DNA. Sequence analysis of the surface (S) antigen corresponding to the amino acid residues 101-186 (including the a-determinant region) revealed a genotype D mutant strain, subtype ayw3 with a single amino acid substitution D144E within the S gene. CONCLUSION: This case suggested that immunosuppressive treatment enhanced with rituximab promoted the emergence of an HBV mutant within the determinant region of the S antigen, which escaped HBIg immunoprophylaxis causing HBV reactivation in a kidney transplant recipient.


Asunto(s)
Antígenos de Superficie de la Hepatitis B/genética , Virus de la Hepatitis B/genética , Hepatitis B Crónica/virología , Inmunosupresores/efectos adversos , Trasplante de Riñón/inmunología , Mutación , Activación Viral , Anticuerpos Monoclonales de Origen Murino/efectos adversos , Secuencia de Bases , Biomarcadores/sangre , Ciclosporina/efectos adversos , Análisis Mutacional de ADN , ADN Viral/sangre , Quimioterapia Combinada , Virus de la Hepatitis B/inmunología , Hepatitis B Crónica/diagnóstico , Hepatitis B Crónica/prevención & control , Humanos , Inmunización Pasiva , Inmunoglobulinas/administración & dosificación , Trasplante de Riñón/efectos adversos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Ácido Micofenólico/efectos adversos , Ácido Micofenólico/análogos & derivados , Prednisolona/efectos adversos , Rituximab , Resultado del Tratamiento , Carga Viral
11.
Int J Immunopathol Pharmacol ; 22(1): 169-74, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19309564

RESUMEN

In this study we investigate the effect of Trichinella spiralis vaccination on immune responses elicited in BALB/c mice challenged subcutaneously with 0.5 x 10 6 of Leishmania infantum promastigotes. Secretion of specific anti-L. infantum antibodies and changes in the number of CD4+, CD8+ T cell and CD19+ B cells in the peripheral blood were tested for the evaluation of immune responses. Immunization with low amounts of T. spiralis antigens induced depression in anti-Leishmania specific antibodies of the IgG1 isotype, while no changes in the number of CD4+ and CD8+ T cell subpopulations or CD19+ B cells were observed. In contrast, high amounts of T. spiralis antigens induced an enhancement in anti-Leishmania specific antibodies of total IgG and IgG1 isotype, increase of CD8+ T cell number and activation of CD19+ B cells, indicated by the co-expression of CD69 marker. Our results suggest that immunization with a certain dose of T. spiralis antigens in experimentally challenged mice with L. infantum leads to an increase of peripheral CD8+ T cells which are responsible for the control of L. infantum infection, although a simultaneous enhancement in Th2-type of immune response is also observed.


Asunto(s)
Antígenos Helmínticos/inmunología , Linfocitos T CD8-positivos/inmunología , Leishmania infantum/inmunología , Leishmaniasis Visceral/inmunología , Células Th2/inmunología , Trichinella spiralis/inmunología , Vacunación , Animales , Anticuerpos Antiprotozoarios/sangre , Femenino , Inmunoglobulina G/sangre , Ratones , Ratones Endogámicos BALB C
12.
Transplant Proc ; 40(9): 3182-4, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19010227

RESUMEN

BACKGROUND: Detection of new biomarkers for hepatocellular carcinoma (HCC) is needed to estimate prognosis after liver transplantation (OLT) or hepatic resection. Osteopontin (OPN) is a secreted, calcium-binding, phosphorylated, acidic glycoprotein that is overexpressed in various cancers. Cluster differentiation 44 standard isoform (CD44s) is one of the primary receptors of OPN; it may contribute to metastatic tumor spread. MATERIALS AND METHODS: Tumor tissue and surrounding hepatic parenchyma were obtained from 53 HCC patients who underwent liver resection. Their RNA was extracted from nitrogen-frozen tissues, and OPN mRNA levels were estimated by quantitative reverse transcription-polymerase chain reactions. Formalin-fixed, paraffin-embedded tissues were obtained from the same patients, and additionally from 60 OLT HCC patients to perform expression analysis for OPN and CD44s by standard avidin-biotin immunostaining methods. RESULTS: Expression of OPN and CD44s was significantly higher among HCC compared with adjacent nontumor tissue. The OPN mRNA expression and protein abundance correlated positively; OPN overexpression was associated with high tumor grade. A positive correlation existed between OPN and CD44s expression; both proteins were significantly overexpressed in HCC lesions with positive lymph nodes. No significant correlation existed between patient survival and OPN and CD44s expression. CONCLUSION: Expression of both OPN and CD44s in HCC is associated with advanced tumor stage, thus possibly contributing prognostic information when evaluated together with classical clinicopathological parameters.


Asunto(s)
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/cirugía , Receptores de Hialuranos/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/cirugía , Trasplante de Hígado , Osteopontina/genética , Adolescente , Adulto , Anciano , Antígenos CD/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , ARN Mensajero/genética , ARN Neoplásico/genética , ARN Neoplásico/aislamiento & purificación , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Adulto Joven
13.
Eur J Med Res ; 13(4): 154-62, 2008 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-18504170

RESUMEN

AIM: We have investigated CsA induced liver hyperplasia to explore the potential effects on the immunogenicity of the regenerating liver within the clinical context of rejection after transplantation. MATERIALS AND METHODS: Flow cytometry analysis of hepatocytes, isolated 48 hours after 2/3 partial hepatectomy (PH2/3) or sham operation in rats, was performed to determine the effect of CsA on DNA synthesis and MHC molecule expression. The possible role of PGE2 was evaluated by the administration of SC-19220, an EP1-PGE2 receptor antagonist. RESULTS: CsA augmented liver regeneration and this was partially attenuated by SC-19220. The moderate expression of class I MHC expression, as well as the very low class II MHC expression detected in normal hepatocytes by flow cytometry was augmented after PH2/3 and reduced by CsA. The CsA-mediated decrease of hepatocyte immunogenicity was not SC-19220 dependent. CONCLUSIONS: It is proposed that the enhancing effect of CsA on hepatocyte proliferation is by means of an indirect mechanism that can be attributed to a) reduced immunogenicity of the regenerating liver as a result of inhibition of class I and II MHC hepatocyte expression and b) increased PGE2 synthesis in the liver mediated by its action on EP1 receptor.


Asunto(s)
Ciclosporina/farmacología , Dinoprostona/metabolismo , Inmunosupresores/farmacología , Regeneración Hepática/efectos de los fármacos , Regeneración Hepática/inmunología , Complejo Mayor de Histocompatibilidad/inmunología , Animales , División Celular/efectos de los fármacos , División Celular/fisiología , ADN/biosíntesis , Ácido Dibenzo(b,f)(1,4)oxazepina-10(11H)-carboxílico, 8-cloro-, 2-acetilhidrazida/farmacología , Citometría de Flujo , Hepatectomía , Hepatocitos/efectos de los fármacos , Hepatocitos/inmunología , Masculino , Antagonistas de Prostaglandina/farmacología , Ratas , Ratas Wistar , Receptores de Prostaglandina E/antagonistas & inhibidores , Receptores de Prostaglandina E/metabolismo , Subtipo EP1 de Receptores de Prostaglandina E
14.
Eur J Immunol ; 19(1): 131-5, 1989 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2646134

RESUMEN

Sequential sublining was used in combination with enzyme-linked immunosorbent assays to isolate mu----gamma isotype switch variants of the rat IgM secreting mouse-rat B cell hybridoma line BA1.8. Switch variants to all four subclasses of IgG were obtained. The variant antibodies retained the antigen specificity of the parental IgM for the O18 (lipopolysaccharide) antigen of Escherichia coli. In sodium dodecyl sulfate-polyacrylamide gels the apparent molecular mass of the gamma heavy chains decreased in the order gamma 2b greater than gamma 1 greater than gamma 2c greater than gamma 2a. IgM, IgG1, IgG2a, IgG2b and IgG2c of the BA1.8 variant family and IgG2b, IgE and IgA of the previously described BA1.2 family were used for a comparative analysis of the capacity of rat Ig to activate complement. Efficient lysis of sheep erythrocytes coated with the O18 antigen was observed with IgM and all IgG subclasses, but no lysis was triggered by IgE or IgA. One hundred to 1000 IgG molecules were required to mediate the same hemolytic activity as one IgM molecule. The four IgG subclasses were equally efficient at mediating lysis by rat or human complement, while IgG2a was less efficient with guinea pig complement than the other three IgG subclasses. Antibody-triggered binding of C3 to pathogenic O18:K1 E. coli bacteria was measured using serum containing 125I-labeled C3. K1-encapsulated strains did not fix C3 efficiently in the absence of specific antibodies while acapsular mutants fixed C3 via the alternative pathway. IgM and all IgG subclasses triggered C3 binding to the K1 encapsulated bacteria. The capacity of IgM to mediate C3 fixation was not greater than that observed with IgG.


Asunto(s)
Activación de Complemento , Hibridomas/metabolismo , Inmunoglobulina G/genética , Isotipos de Inmunoglobulinas/genética , Inmunoglobulina M/genética , Animales , Separación Celular , Complemento C3/metabolismo , Escherichia coli/metabolismo , Variación Genética , Pruebas de Hemaglutinación , Inmunoglobulina A/fisiología , Inmunoglobulina E/fisiología , Inmunoglobulina G/biosíntesis , Inmunoglobulina G/fisiología , Inmunoglobulina M/biosíntesis , Inmunoglobulina M/fisiología , Ratones , Conejos , Ratas
15.
J Immunol ; 140(5): 1577-80, 1988 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-3279119

RESUMEN

In this study, a peptide of 34 amino acids from the Mr 40,000 C terminus alpha-chain fragment of C3 was found to mediate properdin (P) binding. Treatment of the Mr 40,000 fragment with CNBr generated one major Mr 17,000 fragment that was capable of binding P. Amino acid sequence data placed the Mr 17,000 fragment within residues 1385 to 1540 of the C3 sequence. After analyzing this sequence for highly conserved segments within the C3 from other species (which bind P) and segments of low similarity within human C4, mouse C5, and alpha 2-macroglobulin (which do not bind P), a 34-amino acid (1402 to 1435) peptide was synthesized. This synthetic peptide bound to P and inhibited its binding to C3b. In addition, it exhibited negative regulatory activity on the alternative pathway as it inhibited the lysis of rabbit erythrocytes by normal human serum. These results show that the P-binding site is located within the residues 1402 to 1435 of the C3 sequence.


Asunto(s)
Complemento C3/fisiología , Fragmentos de Péptidos/aislamiento & purificación , Properdina/metabolismo , Receptores de Complemento/análisis , Secuencia de Aminoácidos , Animales , Unión Competitiva , Complemento C3/metabolismo , Vía Alternativa del Complemento/efectos de los fármacos , Humanos , Antígeno de Macrófago-1 , Ratones , Datos de Secuencia Molecular , Peso Molecular , Fragmentos de Péptidos/síntesis química , Fragmentos de Péptidos/farmacología , Conejos , Especificidad de la Especie
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