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1.
Work ; 76(2): 611-621, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36911965

RESUMEN

BACKGROUND: Studies are available on physician burnout and job satisfaction (JS) in relation to the specific income structure of the country of residence. However, no studies exist that investigate burnout of immigrated physicians taking into account the income structure of their country of origin (IS-COO) as well as duration of immigration. OBJECTIVE: To determine the influence of IS-COO on JS, income satisfaction, and critical burnout thresholds in the domains of emotional exhaustion (EE), depersonalization (DP) and reduction in personal accomplishment (RPA) among urologists with a migrant background working at German hospitals. METHODS: A questionnaire (Survey-Monkey®/101-items) was conducted among urologists of German hospitals with a migrant background. The online questionnaire was open for study participation from 1 August to 31 October 2020. The study included all physicians with a migration background who were born in a country other than Germany and were currently employed in a German department of urology. Physician burnout (Maslach-Burnout-Inventory) and JS were assessed using validated instruments. The influence of IS-COO and different covariates on the designated endpoints was tested using multivariate-models. RESULTS: 96 urologists with a median stay in Germany of 7 years participated and were stratified according to low (LIC/41.7%), middle (MIC/36.5%) and high (HIC/21.9%) income based on IS-COO. No significant influence of IS-COO on critical thresholds in each burnout domain could be found. Of urologists from LIC, MIC and HIC, 42%, 59% and 57%, respectively, showed rather or extreme JS (p = .446). There was also no significant difference between groups in income satisfaction (p = .838). However, in multivariate-models, duration of stay in Germany (≥7 vs. <7 years) had significant effects on DP (OR: 0.28, p = .038) and RPA (OR: 0.09, p = .014), but not on EE and JS. CONCLUSION: IS-COO has no impact on burnout and JS among urologists who immigrated to Germany. Similarly, income satisfaction in the country of residence is not influenced by IS-COO.

2.
Urol Int ; 106(12): 1304-1312, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34515248

RESUMEN

BACKGROUND: Studies exist that identify factors associated with higher professional satisfaction among clinicians. However, there are no reliable findings for clinicians with a migration background as to whether there is a correlation between particular dimensions of professional satisfaction and the desire to leave their current specialty or country of employment. For the first time, these data were collected within a questionnaire-based study from urological clinicians with a migration background (UCMBs) working in Germany. MATERIAL AND METHODS: A SurveyMonkey® with 101 items relating to characterizing features of the study participants and questions about job satisfaction (n = 39) was opened for UCMBs between August and October 2020. The influence of different dimensions of job satisfaction on the desire to quit the urological specialty/leave Germany was analyzed (group A: neither want to leave urology nor Germany; group B: can at least imagine leaving the urological profession and/or Germany). RESULTS: Eighty-one UCMBs were distributed almost equally in groups A (50.6%) and B (49.4%). Occupational satisfaction was higher in several respects in group A. Three dimensions that differed significantly with regard to occupational satisfaction were used to create an aggregate score ranging from 3 to 15 points as follows: (1) relationship to superiors (p = 0.014), (2) career opportunities in the clinic (p < 0.001), and (3) opportunities for the further development of surgical skills (p = 0.006). For each point value of this aggregate score, the UCMB's desire to quit urology or leave Germany (or at least uncertainty about this question) decreased by a relative value of 34.6% (odds ratio: 0.654, 95% confidence interval: 0.496-0.861, p = 0.002). CONCLUSIONS: Various dimensions of job satisfaction have been identified, the improvement of which could contribute to the long-term retention of UCMBs at German urological clinics.


Asunto(s)
Hospitales , Humanos , Estudios Transversales , Alemania
3.
Psychiatr Prax ; 48(7): 371-377, 2021 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-33472266

RESUMEN

OBJECTIVE: Burnout is considered to be a major risk factor that can contribute secondary disorders due to persistent work related stress. International studies showed that physicians working in psychiatric care are more frequently affected by burnout than physicians working in somatic care. Studies from Germany are lacking. METHODS: In a cross-sectional study all physicians 40 years and younger and registered with the State Chamber of Physicians of Saxony, Germany, received an anonymous paper-pencil questionnaire. Burnout was measured using the Maslach Burnout Inventory. RESULTS: Physicians working in psychiatric/psychosomatic care did not differ from physicians working in somatic care regarding the subscales emotional exhaustion and depersonalization. Physicians working in psychiatric/psychosomatic care reported higher personal accomplishment. Working in psychiatric/psychosomatic care was associated with a lower likelihood for a high degree of burnout on the subscale personal accomplishment. CONCLUSION: Previous studies suggesting a higher prevalence of burnout among physicians working in psychiatric care could not be confirmed.


Asunto(s)
Agotamiento Profesional , Médicos , Agotamiento Profesional/epidemiología , Agotamiento Psicológico , Estudios Transversales , Alemania , Humanos
4.
BMC Health Serv Res ; 18(1): 341, 2018 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-29743052

RESUMEN

BACKGROUND: Physician migration has been gaining attention worldwide. In Germany, physician migration became a topic of interest in the context of the discussion about a shortage of physicians, for which one contributing factor may be physicians leaving the country. However, there is a lack of literature on "push" factors causing German physicians to leave. The present study seeks to provide current data in an effort to promote the identification of "push" factors motivating German physicians to emigrate. METHODS: In a cross-sectional survey, all physicians ≤40 years of age registered with the State Chamber of Physicians of Saxony, Germany (n = 5956) were sent a paper-pencil questionnaire examining socio-demographics, job satisfaction, the wish to emigrate, and the likelihood of moving abroad in the near future. Variables associated with the wish to emigrate were assessed with multivariate logistic regression models. RESULTS: Approximately 30% of participants wished to emigrate. The favourite destination countries were Switzerland, Scandinavian countries, and Australia or New Zealand. Of participants wishing to emigrate, approximately 52% thought it likely to emigrate for a limited, and 15% for an unlimited period of time. Participants with the wish to emigrate were significantly less satisfied with their job situation as compared to physicians without the wish to emigrate, the one exception being their "relationship with patients". The three aspects with the highest difference in satisfaction were the overall work situation, followed by work load, and time for family, friends, and leisure activities. Being a woman, being in a relationship, and having children were associated with a lower chance for wishing to emigrate. Higher satisfaction with the factors "work load", "patient care", and "structural aspects" was also associated with a lower chance for wishing to emigrate. CONCLUSIONS: Emigration seems to be a viable option for at least a subset of physicians. Preventive measures should address modifiable determinants associated with an increased chance for wishing to emigrate, such as job satisfaction. Especially satisfaction with the factor "work load" seems to play a crucial role as a "push" factor for physician emigration.


Asunto(s)
Emigración e Inmigración , Médicos/provisión & distribución , Adulto , Australia , Estudios Transversales , Femenino , Alemania , Humanos , Satisfacción en el Trabajo , Masculino , Motivación , Nueva Zelanda , Encuestas y Cuestionarios , Suiza , Carga de Trabajo/estadística & datos numéricos
5.
J Occup Med Toxicol ; 11(1): 41, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27582781

RESUMEN

BACKGROUND: Physician migration is gaining attention worldwide. Despite increasing numbers of foreign physicians in Germany, their perceptions on working in Germany remain unexplored. Within a large survey on Saxon physicians, the aim of this study was to elucidate whether foreign-national physicians' job satisfaction differed from German physicians' job satisfaction. METHODS: The study was designed as a comprehensive cross-sectional survey. All physicians ≤40 years and registered with the State Chamber of Physicians of Saxony (n = 5956) were mailed a paper-pencil questionnaire, of which 2357 were returned (response rate = 40 %). Questionnaires addressed socio-demographics and assessed job satisfaction by asking participants to rate their satisfaction with the overall job situation and 20 different aspects on a 5-point Likert scale (1 = very dissatisfied to 5 = very satisfied). RESULTS: Ten percent of participants were foreign-national physicians. The three main countries of origin were the Czech Republic, Slovakia, and Poland. Foreign-national physicians were more satisfied with aspects related to patient care, such as "possibility to treat patients as you deem optimal" and "relationship with patients". However, they were less satisfied with aspects related to human relations, such as "work atmosphere", relationship with co-workers, and "social status". Foreign-national physicians were also less satisfied with the aspect "work enjoyment". CONCLUSIONS: Further research on determinants promoting foreign-national physicians' job satisfaction is needed as their professional well-being may influence quality of patient care. Measures teaching cross-cultural competence and awareness may be beneficial for both foreign-national and German physicians.

6.
J Occup Med Toxicol ; 11: 2, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26807138

RESUMEN

BACKGROUND: Concerns about burnout, and its consequences, among German physicians are rising. However, data on burnout among German physicians are scarce. Also, a suspected association between burnout and German physicians' wishes to leave remains to be studied. Therefore, the extent of burnout, and the association between burnout and wishes to leave clinical practice or to go abroad for clinical work was studied in a sample of young physicians in Saxony. METHODS: In a cross-sectional survey, all physicians ≤40 years and registered with the State Chamber of Physicians of Saxony, Germany (n = 5956) received a paper-pencil questionnaire inquiring about socio-demographics, job satisfaction, and wishes to leave clinical practice or to go abroad for clinical work. Response rate was 40 % (n = 2357). Burnout was measured with the German version of the Maslach Burnout Inventory - Human Services Survey (MBI) consisting of the subscales emotional exhaustion (feeling emotionally drained), depersonalization (feelings of cynicsm) and personal accomplishment (feelings of personal achievement in job). Variables associated with burnout, and the association between burnout and wishes to leave were assessed in multivariate logistic regression analyses. RESULTS: For emotional exhaustion participants reached a mean of 21.3 [standard deviation = 9.74], for depersonalization a mean of 9.9 [5.92], and for personal accomplishment a mean of 36.3 [6.77]. Men exhibited significantly higher depersonalization than women (11.3 [6.11] versus 9 [5.62], p < 0.001). Eleven percent of participants showed a high degree of burnout on all subscales, while 35 % did not show a high degree of burnout on any subscale. Confirming that one would become a physician again, and higher satisfaction with the components "work environment" and "humaneness", were associated with a lower chance for a high degree of burnout on all subscales. Higher emotional exhaustion and lower personal accomplishment were associated with an increased chance of wishing to leave clinical practice. Higher emotional exhaustion and higher depersonalization were associated with an increased chance of wishing to go abroad for clinical work. CONCLUSIONS: Preventing physician burnout may not only benefit the affected individual. It may also benefit the health care system by potentially preventing physicians from leaving clinical practice or from going abroad for clinical work.

7.
Psychiatr Prax ; 43(8): 436-440, 2016 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-26556683

RESUMEN

Objective: Analysis of job satisfaction and intentions to quit among physicians working in psychiatric/psychosomatic care compared to physicians working in somatic care. Methods: Full postal survey of all physicians ≤ 40 years of age registered with the State Chamber of Physicians of Saxony (response rate 40 %, n = 2357). Analysis was restricted to physicians working in patient care (n = 1901). Results: Physicians working in psychiatric/psychosomatic care as well as those in somatic care were rather satisfied with their overall job situation (mean: 3.48 [standard deviation: 1.01] vs. 3.40 [0.94], 5 point Likert scale). Physicians working in psychiatric/psychosomatic care were less satisfied with only 2 out of 20 aspects of job satisfaction. Nearly a quarter wished to leave patient care or to go abroad, which did not differ from physicians working in somatic care. Conclusion: The present study did not confirm international results indicating lower job satisfaction among psychiatrists.


Asunto(s)
Satisfacción en el Trabajo , Médicos/psicología , Psiquiatría , Medicina Psicosomática , Adulto , Selección de Profesión , Femenino , Humanos , Masculino , Encuestas y Cuestionarios
8.
Am J Trop Med Hyg ; 91(3): 555-62, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25092824

RESUMEN

Childhood diarrhea is an important cause of malnutrition, which can be worsened when caretakers limit nutritional support. We queried 390 caregivers and their children in a peri-urban community in Lima, Peru regarding general perceptions of feeding and feeding practices during diarrhea. Overall, 22.1% of caregivers perceived feeding during diarrhea to be harmful. At baseline, 71.9% of caregivers would discontinue normal feeding or give less food. Most would withhold milk, eggs, and meats. Approximately 40% of caregivers would withhold vegetables and fruits. A pilot educational intervention was performed to improve feeding during diarrhea. At follow-up survey 3 months later, none of the caregivers would recommend withholding food. Only 23.2% would recommend discontinuing normal feeding and 1.8% perceived food to be damaging. Misperceptions of the role of feeding during diarrhea pose a significant health risk for children, but a simple educational intervention might have a major impact on these perceptions and practices.


Asunto(s)
Cuidadores/psicología , Diarrea/terapia , Conocimientos, Actitudes y Práctica en Salud , Madres/psicología , Adolescente , Adulto , Anciano , Lactancia Materna , Cuidadores/educación , Preescolar , Diarrea/complicaciones , Diarrea/epidemiología , Ingestión de Alimentos , Femenino , Estudios de Seguimiento , Alimentos/clasificación , Atención Domiciliaria de Salud , Humanos , Lactante , Masculino , Persona de Mediana Edad , Madres/educación , Percepción , Perú/epidemiología , Encuestas y Cuestionarios , Adulto Joven
9.
PLoS One ; 7(11): e48113, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23144850

RESUMEN

OBJECTIVE: Studies from the USA have identified medical students as a major source of stigmatizing attitudes towards overweight and obese individuals. As data from Europe is scarce, medical students' attitudes were investigated at the University of Leipzig in Leipzig, Germany. DESIGN: Cross-sectional survey containing an experimental manipulation consisting of a pair of vignettes depicting an obese and a normal weight 42-year-old woman, respectively. Vignettes were followed by the Fat Phobia Scale (FPS), a semantic differential assessing weight related attitudes. In case of the overweight vignette a panel of questions on causal attribution for the overweight preceded administration of the FPS. SUBJECTS: 671 medical students were enrolled at the University of Leipzig from May to June 2011. RESULTS: The overweight vignette was rated significantly more negative than the normal weight vignette (mean FPS score 3.65±0.45 versus 2.54±0.38, p<0.001). A higher proportion of students had negative attitudes towards the overweight as compared to the normal weight individual (98.9% versus 53.7%, p<0.001). A "positive energy balance" was perceived as the most relevant cause for the overweight, followed by "negligent personality trait", "societal and social environment" and "biomedical causes". Attributing a "positive energy balance" or "negligent personality trait" as relevant cause for the overweight was positively associated with negative attitudes. CONCLUSION: The results of this study confirm and complement findings from other countries, mainly the USA, and indicate that weight bias in the health care setting may be a global issue. Stigmatizing attitudes towards overweight and obesity are prevalent among a sample of medical students at the University of Leipzig. Negative attitudes arise on the basis of holding the individual accountable for the excess weight. They call for bringing the topic of overweight and obesity more into the focus of the medical curriculum and for enhancing medical students' awareness of the complex aetiology of this health condition.


Asunto(s)
Actitud del Personal de Salud , Obesidad/psicología , Estudiantes de Medicina/psicología , Adolescente , Adulto , Estudios Transversales , Discriminación en Psicología , Femenino , Alemania , Humanos , Masculino , Prejuicio , Facultades de Medicina , Encuestas y Cuestionarios , Adulto Joven
10.
Am J Trop Med Hyg ; 86(6): 922-4, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22665594

RESUMEN

Caregivers' practices concerning oral rehydration of young children during diarrheal illness were investigated in a periurban community of low socioeconomic level in Lima, Peru. Data of 330 caregivers of children aged 6-36 months were analyzed; 72.7% of all caregivers would give commercially available oral rehydration solutions (ORSs). However, only 58.6% of those caregivers with children that had experienced diarrhea during the previous week stated that they had used commercially available ORSs, a significantly lower percentage. The main reason for not using commercially available ORSs was that caregivers did not know about them. Of all recipes caregivers provided for homemade ORS, none contained the recommended concentrations of sugar and salt. Educating caregivers about availability, benefits, and use of commercially available ORSs as well as correct preparation of homemade ORS is urgently needed.


Asunto(s)
Diarrea/tratamiento farmacológico , Diarrea/epidemiología , Fluidoterapia , Soluciones para Rehidratación/uso terapéutico , Bicarbonatos/uso terapéutico , Cuidadores , Preescolar , Femenino , Glucosa/uso terapéutico , Conocimientos, Actitudes y Práctica en Salud , Humanos , Lactante , Masculino , Perú/epidemiología , Cloruro de Potasio/uso terapéutico , Factores Socioeconómicos , Cloruro de Sodio/uso terapéutico
11.
Travel Med Infect Dis ; 9(2): 75-81, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21420363

RESUMEN

The risks associated with alcohol intoxication are rarely discussed during pre-travel counselling. However, alcohol immoderation abroad may increase the exposure to health risks. Few studies have addressed alcohol consumption and risk taking behaviour in travellers to South America. From October to December of 2004, travellers leaving the city of Cusco in Peru were asked to fill out anonymous questionnaires regarding demographics, self-reported alcohol consumption, illness and risk behaviour for sexually-transmitted infection (STI) and travellers diarrhoea. Most travellers (87.2%) consumed alcohol and 20.4% reported inebriation in Cusco. Those admitting inebriation were more likely to be male, single, <26 years old, and travelling alone or with friends. Travellers who admitted inebriation and fell ill while in Cusco were more likely to seek medical attention, change itinerary, and report decreased satisfaction with the trip experience. In the multivariate analysis, inebriation was independently associated with reporting higher numbers of unsafe food choices, illicit drug use, and risky sexual activity. It is concluded that alcohol intoxication during travel was associated with increased risk taking behaviour for common travel related conditions. Although travel related illnesses were not associated with inebriation, some markers of illness severity were more often reported by those who admitted intoxication. Risk for heavy alcohol use abroad should be assessed during the pre-travel visit in certain groups and appropriate counselling should be provided.


Asunto(s)
Consumo de Bebidas Alcohólicas/epidemiología , Asunción de Riesgos , Viaje/estadística & datos numéricos , Adolescente , Adulto , Niño , Preescolar , Diarrea/epidemiología , Femenino , Humanos , Drogas Ilícitas , Masculino , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Perú , Conducta Sexual , Enfermedades de Transmisión Sexual/epidemiología , Encuestas y Cuestionarios , Medicina del Viajero
12.
Am J Trop Med Hyg ; 82(4): 600-7, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20348507

RESUMEN

Intracellular protozoans of the genus Cryptosporidium are a major cause of diarrheal illness worldwide, especially in immunocompromised individuals. CD4(+) T cells and interferon-gamma are key factors in the control of cryptosporidiosis in human and murine models. Previous studies led us to hypothesize that CD8(+) T cells contribute to clearance of intestinal epithelial Cryptosporidium infection in humans. We report here that antigen expanded sensitized CD8(+) T cells reduce the parasite load in infected intestinal epithelial cell cultures and lyse infected intestinal epithelial cells. These effects are most likely mediated by the release of cytotoxic granules. Elimination of parasites seems to require antigen presentation through both human leukocyte antigen (HLA)-A and HLA-B. These data suggest that cytotoxic CD8(+) T cells play a role in clearing Cryptosporidium from the intestine, a previously unrecognized feature of the human immune response against this parasite.


Asunto(s)
Linfocitos T CD8-positivos/fisiología , Cryptosporidium parvum/fisiología , Células Epiteliales/parasitología , Mucosa Intestinal/citología , Animales , Anticuerpos Antiprotozoarios , Antígenos de Protozoos , Células CACO-2 , Antígenos HLA , Humanos
14.
J Infect Dis ; 197(6): 916-23, 2008 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-18288900

RESUMEN

Cryptosporidium parasites are pathogens of human intestinal epithelial cells. To determine which genes are regulated during early infection, human ileal mucosa cultured as explants was infected with C. parvum or C. hominis, and gene expression was analyzed by microarray. The gene for osteoprotegerin (OPG) was up-regulated by both parasites. OPG mRNA was also significantly increased in biopsy specimens obtained from a volunteer experimentally infected with C. meleagridis, compared with levels in a prechallenge biopsy specimen. After in vitro infection of HCT-8 cells, there was an early peak in production of OPG mRNA protein. Treatment of infected cells with the OPG ligand tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induced epithelial cell apoptosis and reduced parasite numbers, and recombinant OPG blocked these effects. These results suggest a novel TRAIL-mediated pathway for elimination of Cryptosporidium infection and a role for OPG in modulating this host response.


Asunto(s)
Criptosporidiosis/inmunología , Criptosporidiosis/metabolismo , Cryptosporidium/aislamiento & purificación , Mucosa Intestinal/inmunología , Mucosa Intestinal/parasitología , Osteoprotegerina/biosíntesis , Animales , Apoptosis/fisiología , Células Cultivadas , Criptosporidiosis/parasitología , Cryptosporidium/fisiología , Interacciones Huésped-Parásitos/fisiología , Humanos , Mucosa Intestinal/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Osteoprotegerina/inmunología , Osteoprotegerina/metabolismo , Sus scrofa , Ligando Inductor de Apoptosis Relacionado con TNF/antagonistas & inhibidores , Ligando Inductor de Apoptosis Relacionado con TNF/inmunología
16.
Int Immunopharmacol ; 4(1): 15-24, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14975356

RESUMEN

Aluminum hydroxide and incomplete Freund's adjuvant (IFA) are the only adjuvants approved for human use. Both are T helper 2 (Th2) adjuvants, however, T helper 1 (Th1) immunity is induced if microbial products such as mycobacteria, CpG's, or bacterial toxins are included in the adjuvant preparation. The usefulness of bacterial toxins, such as Pertussis toxin (PT) or Cholera toxin (CT), as adjuvants for human vaccination is limited by toxic side effects and high immunogenicity. Hence, we asked whether or not the adjuvant activity of bacterial toxins on Th1 and Th2 immunity could be mimicked by chemical compounds of small molecular weight and less immunogenicity. In the present study, we show that Suramin, a small molecular weight naphthylurea, which mainly acts on G-proteins and on P2X/P2Y receptors, promotes expansion of hen eggwhite lysozyme (HEL)-specific Th1 and Th2 cells upon immunization of BALB/c mice with HEL in aluminum hydroxide (alum). The results indicated that the adjuvant effects of Suramin on T cell responses were mediated by enhancing the expression of MHC class II and costimulatory molecules on antigen presenting cells (APCs), and by increasing their pro-inflammatory cytokine production. Together, the results suggest that small molecular weight compounds such as Suramin could be used as alternative vaccine adjuvants.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Proteínas de Unión al GTP/antagonistas & inhibidores , Antagonistas del Receptor Purinérgico P2 , Suramina/farmacología , Células TH1/efectos de los fármacos , Células Th2/efectos de los fármacos , Hidróxido de Aluminio/farmacología , Animales , Femenino , Adyuvante de Freund/farmacología , Proteínas de Unión al GTP/agonistas , Rechazo de Injerto/inmunología , Inmunización , Técnicas In Vitro , Interleucina-12/metabolismo , Interleucina-6/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Muramidasa/inmunología , Trasplante de Piel/inmunología , Células TH1/citología , Células TH1/inmunología , Células Th2/citología , Células Th2/inmunología
17.
J Immunol ; 169(7): 3686-93, 2002 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-12244161

RESUMEN

Alloreactive T lymphocytes can be primed through direct presentation of donor MHC:peptide complexes on graft cells and through indirect presentation of donor-derived determinants expressed by recipient APCs. The large numbers of determinants on an allograft and the high frequency of the alloreactive repertoire has further led to speculation that exposure to environmental Ags may prime T cells that cross-react with alloantigens. We sought to develop a model in which to test this hypothesis. We found that CD4(+) T cells obtained from C57BL/6 (B6) mice that clinically resolved Leishmania major infection exhibited statistically significant cross-reactivity toward P/J (H-2(p)) Ags compared with the response to other haplotypes. B6 animals that were previously infected with L. major specifically rejected P/J skin grafts with second set kinetics compared with naive animals. Although donor-specific transfusion combined with costimulatory blockade (anti-CD40 ligand Ab) induced prolonged graft survival in naive animals, the same treatment was ineffective in mice previously infected with L. major. The studies demonstrate that cross-reactive priming of alloreactive T cells can occur and provide direct evidence that such T cells can have a significant impact on the outcome of an allograft. The results have important implications for human transplant recipients whose immune repertoires may contain cross-reactively primed allospecific T cells.


Asunto(s)
Rechazo de Injerto/inmunología , Isoantígenos/metabolismo , Leishmania major/inmunología , Leishmaniasis Cutánea/inmunología , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/parasitología , Secuencia de Aminoácidos , Animales , Antígenos/inmunología , Antígenos/metabolismo , Pollos , Reacciones Cruzadas , Modelos Animales de Enfermedad , Femenino , Rechazo de Injerto/parasitología , Isoantígenos/inmunología , Leishmaniasis Cutánea/parasitología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Datos de Secuencia Molecular , Muramidasa/inmunología , Muramidasa/metabolismo , Ovalbúmina/inmunología , Ovalbúmina/metabolismo , Conejos , Trasplante de Piel/inmunología , Subgrupos de Linfocitos T/metabolismo , Vacunación
18.
Am J Transplant ; 2(6): 501-9, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12118893

RESUMEN

Costimulatory blockade can induce long-term allograft survival in naive animals, but may not be as effective in animals with previously primed immune repertoires. We attempted to induce long-term graft survival in B10.D2 recipients of B10.A cardiac allografts using donor-specific transfusion (DST) plus anti-CD40 ligand antibody (alphaCD40L). Recipients were either naive mice, or mice previously primed to B10.A or third party alloantigens through engraftment and rejection of skin transplants. Untreated naïve mice rejected cardiac transplants by day 15 and contained a high frequency of primed, donor-reactive T cells. Donor-specific transfusion/alphaCD4OL treatment of naïve animals induced long-term graft survival associated with low frequencies of donor-reactive T cells. Previous priming of donor-specific T cells through rejection of B10.A, but not third party, skin grafts prevented the effects of DST/alphaCD40L on prolonging survival of B10.A hearts. Moreover, adoptive transfer of CD3+, CD4+ or CD8+ T cells from B10.A skin-graft-primed animals prevented the effects of DST/alphaCD40L. The data demonstrate that animals with immune repertoires containing previously primed, donor-reactive T cells are resistant to the effects of costimulatory blockade. The findings have important implications for ongoing, costimulatory blockade-based trials in humans, whose T-cell repertoires are known to contain memory alloreactive T cells.


Asunto(s)
Supervivencia de Injerto , Trasplante de Corazón , Linfocitos T/inmunología , Animales , Ligando de CD40/inmunología , Rechazo de Injerto/fisiopatología , Supervivencia de Injerto/inmunología , Interferón gamma/metabolismo , Masculino , Ratones , Trasplante de Piel
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