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1.
Am J Transplant ; 15(10): 2726-31, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25988397

RESUMO

There is no literature on the use of belatacept for sensitized patients or regrafts in kidney transplantation. We present our initial experience in high immunologic risk kidney transplant recipients who were converted from tacrolimus to belatacept for presumed acute calcineurin inhibitor (CNI) toxicity and/or interstitial fibrosis/tubular atrophy. Six (mean age = 40 years) patients were switched from tacrolimus to belatacept at a median of 4 months posttransplant. Renal function improved significantly from a peak mean estimated glomerular filtration rate (eGFR) of 23.8 ± 12.9 mL/min/1.73 m(2) prior to the switch to an eGFR of 42 ± 12.5 mL/min/1.73 m(2) (p = 0.03) at a mean follow-up of 16.5 months postconversion. No new rejection episodes were diagnosed despite a prior history of rejection in 2/6 (33%) patients. Surveillance biopsies performed in 5/6 patients did not show subclinical rejection. No development of donor-specific antibodies (DSA) was noted. In this preliminary investigation, we report improved kidney function without a concurrent increase in risk of rejection and DSA in six sensitized patients converted from tacrolimus to belatacept. Improvement in renal function was noted even in patients with chronic allograft fibrosis without evidence of acute CNI toxicity. Further studies with protocol biopsies are needed to ensure safety and wider applicability of this approach.


Assuntos
Abatacepte/uso terapêutico , Rejeição de Enxerto/prevenção & controle , Imunossupressores/uso terapêutico , Transplante de Rim , Complicações Pós-Operatórias/induzido quimicamente , Insuficiência Renal/induzido quimicamente , Tacrolimo/efeitos adversos , Adulto , Idoso , Aloenxertos/efeitos dos fármacos , Aloenxertos/fisiopatologia , Feminino , Seguimentos , Humanos , Imunossupressores/efeitos adversos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tacrolimo/uso terapêutico , Transplante Homólogo , Resultado do Tratamento
2.
Psychoneuroendocrinology ; 37(8): 1248-60, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22265196

RESUMO

Estrogen therapy used in combination with selective serotonin reuptake inhibitor (SSRI) treatment improves SSRI efficacy for the treatment of mood disorders. Desensitization of serotonin 1A (5-HT(1A)) receptors, which takes one to two weeks to develop in animals, is necessary for SSRI therapeutic efficacy. Estradiol modifies 5-HT(1A) receptor signaling and induces a partial desensitization in the paraventricular nucleus (PVN) of the rat within two days, but the mechanisms underlying this effect are currently unknown. The purpose of this study was to identify the estrogen receptor necessary for estradiol-induced 5-HT(1A) receptor desensitization. We previously showed that estrogen receptor ß is not necessary for 5-HT(1A) receptor desensitization and that selective activation of estrogen receptor GPR30 mimics the effects of estradiol in rat PVN. Here, we used a recombinant adenovirus containing GPR30 siRNAs to decrease GPR30 expression in the PVN. Reduction of GPR30 prevented estradiol-induced desensitization of 5-HT(1A) receptor as measured by hormonal responses to the selective 5-HT(1A) receptor agonist, (+)8-OH-DPAT. To determine the possible mechanisms underlying these effects, we investigated protein and mRNA levels of 5-HT(1A) receptor signaling components including 5-HT(1A) receptor, Gαz, and RGSz1. We found that two days of estradiol increased protein and mRNA expression of RGSz1, and decreased 5-HT(1A) receptor protein but increased 5-HT(1A) mRNA; GPR30 knockdown prevented the estradiol-induced changes in 5-HT(1A) receptor protein in the PVN. Taken together, these data demonstrate that GPR30 is necessary for estradiol-induced changes in the 5-HT(1A) receptor signaling pathway and desensitization of 5-HT(1A) receptor signaling.


Assuntos
Estradiol/farmacologia , Núcleo Hipotalâmico Paraventricular/efeitos dos fármacos , Receptor 5-HT1A de Serotonina/metabolismo , Receptores Acoplados a Proteínas G/fisiologia , Animais , Feminino , Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Modelos Biológicos , Núcleo Hipotalâmico Paraventricular/metabolismo , RNA Interferente Pequeno/farmacologia , Ratos , Ratos Sprague-Dawley , Receptor 5-HT1A de Serotonina/genética , Receptor 5-HT1A de Serotonina/fisiologia , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Receptores Acoplados a Proteínas G/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
3.
Res Social Adm Pharm ; 5(2): 94-107, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19524858

RESUMO

BACKGROUND: In the sociological context, the concept of cultural lag holds that material technologies advance more rapidly than social guidelines for their use. The result can be social conflict including liability accusations and product stigmatization that have characterized several new drugs which were widely accepted initially but then publicly criticized in the lay and scientific press. OBJECTIVES: The objective was to illustrate the utility of the concept of cultural lag to technology commercialization by applying cultural lag to the social and professional environments surrounding the diffusion of the "minor tranquilizers" Librium and Valium in the United States from the 1950s to the 1970s, and the antidepressant Prozac from 1987 to 2005. The intention is to develop a perspective from which to view patterns of social acceptance followed by critique that may occur when technological advances are introduced to the marketplace. METHODS: This study systematically reviews academic, medical, and lay literature regarding the diffusion of the "minor tranquilizers" Librium and Valium in the United States from the 1950s to the 1970s, and the antidepressant Prozac from 1987 to 2005. RESULTS: The minor tranquilizers and Prozac both reveal similar patterns of initial widespread public endorsement, followed by growing public criticism and recommendations for more restrictive usage guidelines. CONCLUSIONS: Cultural lag provides a perspective from which to anticipate, view, and avoid controversies that develop from new technologies in general and pharmaceutical technologies in particular. Market demands for rapid introduction must be balanced by public education. This requires proactive encouragement of lay and professional discussions and the establishment of marketing guidelines that aid development of social consensus regarding appropriate usage.


Assuntos
Diazepam/uso terapêutico , Fluoxetina/uso terapêutico , Opinião Pública , Ansiolíticos/história , Ansiolíticos/uso terapêutico , Antidepressivos de Segunda Geração/história , Antidepressivos de Segunda Geração/uso terapêutico , Clordiazepóxido/história , Clordiazepóxido/uso terapêutico , Cultura , Diazepam/história , Indústria Farmacêutica/métodos , Fluoxetina/história , História do Século XX , História do Século XXI , Humanos , Marketing/métodos , Meio Social
4.
Tissue Antigens ; 69 Suppl 1: 174-9, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17445195

RESUMO

An international collaborative study of 45 transplant centers was undertaken at the 14th International HLA (human leukocyte antigen) and Immunogenetics Workshop to see if HLA antibodies detected posttransplant are predictive of chronic graft failure. With the newly developed assay, MICA (major histocompatibility complex class I-related chain A) antibodies were also measured and their effect analyzed. Total of 5219 sera from patients who were more than 6 months posttransplant with functioning graft were tested for HLA antibodies by enzyme-linked immunosorbent assay, flow cytometry, or Luminex. HLA antibodies were found in 27.2% of kidney patients, 23.6% in the liver, 52.7% in the heart, and 21.7% in the lung. The method of antibody testing did not have a marked influence on the frequency of antibodies detected. MICA antibodies were detected in 15% of kidney patients, 30% of heart patients, and 31% of liver patients. Among 948 kidney patients who had HLA antibodies, 7.3% had rejected their graft within 1 year of testing, compared with 1.7% in 2615 patients without HLA antibodies (P= 0.8 x 10(-17)). Death occurred in 1.4% of total kidney patients and did not correlate to the presence of antibodies. We conclude that patients with posttransplant HLA antibodies indeed have a higher rate of chronic graft failure and that posttransplant antibodies are predictive of chronic rejection.


Assuntos
Rejeição de Enxerto/etiologia , Antígenos HLA/imunologia , Transplante de Coração/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Imunogenética , Transplante de Rim/imunologia , Imunologia de Transplantes , Doença Crônica , Sobrevivência de Enxerto , Transplante de Coração/efeitos adversos , Teste de Histocompatibilidade , Humanos , Transplante de Rim/efeitos adversos
5.
Transplant Proc ; 38(10): 3416-7, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17175290

RESUMO

Intravenous immunoglobulin (IVIG) desensitization protocols permit transplantation of sensitized renal recipients against alloantibody incompatibility barriers. It appears that IVIG induces a sustained down-regulation of alloantibody that facilitates crossmatch compatibility. However, the consequence of desensitization upon cellular immunity has not been addressed. We compared in vitro proliferative responses and cytokine expression between desensitized transplant recipients (IVIG) and non-IVIG-treated patients (controls). Eleven patients who were crossmatch-incompatible with living donors underwent treatment with IVIG and plasmapheresis. Nine patients converted to negative crossmatches and were transplanted. With a mean follow-up time of 17.6 +/- 6.7 months, graft survival is 100%. Peripheral mononuclear cells were collected 12.5 +/- 9 months after transplantation and tested for proliferative response and cytokine elaboration following challenge with staphylococcal enterotoxin b (SEB) and donor-specific mixed lymphocyte reaction (dMLR). Proliferative reactions were 90% lower (P < .05) among IVIG versus controls in response to SEB and dMLR challenge. Cytokine response to SEB challenge was equivalent (P = NS) between IVIG and controls. In contrast, cytokine elaboration was 60% lower (P < .05) for IVIG versus controls in response to dMLR. One year after renal transplantation, desensitized patients showed in vitro hyporesponsiveness to superantigen and donor-specific challenge. This suggests that IVIG promotes a down-regulation in cellular immunity that may facilitate good graft outcome.


Assuntos
Dessensibilização Imunológica , Imunidade Celular , Imunoglobulinas Intravenosas/uso terapêutico , Transplante de Rim/imunologia , Citotoxicidade Imunológica , Teste de Histocompatibilidade , Humanos , Fatores Imunológicos/uso terapêutico , Doadores Vivos , Reoperação
6.
Transplant Proc ; 38(10): 3695-6, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17175370

RESUMO

Infections are the major complication among patients on left ventricular device (LVAD) support. One mechanism that may explain the elevated incidence of infection is a deficiency in cellular immunity after LVAD placement. To test this hypothesis, we evaluated the in vitro T-cell-proliferative and cytokine response following challenge with staphylococcal enterotoxin B in 14 LVAD and 6 non-LVAD stable outpatients awaiting heart transplantation. Clinical outcome was followed for 12 months. Clinical outcome was poorer (P < .05) for LVAD vs non-LVAD patients. T-cell-proliferative response was lower (P = .002) for LVAD vs non-LVAD patients. Th1 cytokine expression was lower (P < .05) and Th2 cytokine expression was higher (P < .05) for LVAD vs non-LVAD patients. We conclude that LVAD recipients are hyporesponsive to superantigen challenge, indicating a depressed cellular immunity that may contribute to their increased susceptibility to infections.


Assuntos
Enterotoxinas/farmacologia , Insuficiência Cardíaca/imunologia , Insuficiência Cardíaca/terapia , Coração Auxiliar , Linfócitos T/imunologia , Seguimentos , Insuficiência Cardíaca/cirurgia , Ativação Linfocitária/efeitos dos fármacos , Superantígenos/farmacologia , Linfócitos T/efeitos dos fármacos , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Células Th2/efeitos dos fármacos , Células Th2/imunologia , Fatores de Tempo , Resultado do Tratamento
7.
Transplant Proc ; 37(2): 1099-100, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15848634

RESUMO

Hepatitis C (HCV) recurrence following liver transplantation is universal. However, the severity of recurrence is highly variable between patients. We speculated that recipient DR antigens or the level of DR mismatching between the recipient and the donor might affect the severity of HCV recurrence and allograft survival. Clinical outcome was compared between HCV+ recipients with DR2, DR3, or DR5 versus HCV+ recipients with all other DR antigens. Recipients with DR3 had reduced allograft survival (P < .02), a higher rate of HCV recurrence (P < .05), and more severe liver disease (P < .05). Recipients with DR5 had superior allograft survival (P < .05), low rates of HCV recurrence (P < .05), and benign liver disease (P < .05). Clinical outcome of recipients with DR2 was equivalent (P = Ns) to the non-DR2, -3, -5 recipients. The incidence of acute rejection was equivalent (P = Ns) in all groups. The level of DR mismatching between donor and recipient did not affect HCV recurrence or severity. However, allograft survival was better (P < .05) in recipients with zero DR mismatches. The data show that host genetic factors play an important role in HCV recurrence and allograft outcome after liver transplantation. In addition, identification of DR antigens may help predict an HCV+ patient's relative risk for severe HCV recurrence.


Assuntos
Antígenos HLA-DR/imunologia , Hepatite C/imunologia , Transplante de Fígado/imunologia , DNA/genética , DNA/isolamento & purificação , Frequência do Gene , Sobrevivência de Enxerto/imunologia , Antígenos HLA-DR/genética , Antígeno HLA-DR2/genética , Antígeno HLA-DR3/genética , Antígeno HLA-DR5/genética , Hepatite C/cirurgia , Humanos , Recidiva , Resultado do Tratamento
8.
Transplant Proc ; 37(2): 652-3, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15848490

RESUMO

Hepatitis C viremia occurs universally after liver transplantation. It is speculated that soluble HCV proteins may be immunomodulatory. We measured the effects of HCV core upon human T-cell proliferation, expression of activation markers, and interaction with cyclosporine. Cells were activated with anti-CD3 for 2-6 days. Cultivation with 1, 2, 4, and 8 microg/mL core reduced tritiated thymidine uptake by 7% (P = ns), 63% (P < .001), 69% (P < .001) and 92% (P < .001). Direct cell counting (10(4)) showed proliferative inhibition in treated cultures after 2 days (84%, P < .05), 4 days (93%, P < .05), and 6 days (88%, P < .05). Viability remained greater than 90%. Expression of activation markers was reduced with core treatment. Treatment with 4 microg/mL core for 2, 4, and 6 days reduced CD2+CD25+ by 67% (P < .05), 67% (P < .05), and 51% (P < .05) and CD2+DR+ expression by 54% (P < .05), 46% (P < .05), and 54% (P < .05). Interaction between core and cyclosporine was determined by isobologram analysis which determines whether interactions are synergistic, additive or antagonistic. Combining core with cyclosporine resulted in an additive effect upon proliferative suppression. Linear regression confirmed an additive interaction with an r2 value of 0.98. The data shows that soluble core causes dose dependent suppression of T-cell proliferation and may potentiate suppression by cyclosporine.


Assuntos
Ciclosporina/farmacologia , Terapia de Imunossupressão/métodos , Imunossupressores/farmacologia , Proteínas do Core Viral/farmacologia , Sinergismo Farmacológico , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Ativação Linfocitária/efeitos dos fármacos
9.
Transplant Proc ; 37(10): 4191-3, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16387075

RESUMO

We report our experience in assessing autoantibodies among HIV+ patients considered for renal transplantation. Autoantibodies against autologous T and B cells were determined by complement-dependent cytotoxicity autocrossmatching (CDC) or flow cytometric autocrossmatching (FCXM) for 28 HIV+ and 72 HIV- men. T-cell CDC was negative among HIV+ and HIV- individuals (0%). In contrast, B-cell CDC was higher among HIV+ than HIV- patients (71% vs 4%, P = .001). However, HIV+ patients also showed unusual sensitivity to complement that potentially invalidated the B-cell CDC. Complement sensitivity was higher among those with positive versus negative HIV RNA (71% vs 25%, P < .01). Alternate use of FCXM showed equivalent T-cell FCXM between HIV+ versus HIV- individuals (5% vs 1%, P = NS). However, B-cell FCXM was more prevalent among HIV+ than HIV- patients (45% vs 2%, P < .01). B-cell FCXM was higher among patients with positive than negative HIV RNA (57% vs 25%, P < .05). Simulated allocrossmatching against unrelated DR-matched donors showed that two out of four HIV+ patients with positive FCXM had positive allocrossmatches that were eliminated when allocrossmatching was repeated using autoabsorbed serum. We conclude that HIV+ patients are more likely to produce B-cell autoantibodies than HIV- individuals, which, if not realized, could cause false-positive allocrossmatches and inappropriate transplant denial.


Assuntos
Autoanticorpos/sangue , Linfócitos B/imunologia , Soropositividade para HIV/imunologia , Imunoglobulina G/sangue , Linfócitos T/imunologia , Teste de Histocompatibilidade , Humanos , Masculino
10.
J Viral Hepat ; 10(5): 354-9, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12969187

RESUMO

Interferon-alpha (IFN-alpha) is the major treatment for chronic hepatitis C virus (HCV) infection. Drug resistance is problematic, particularly among African-Americans who typically show poorer clinical outcomes than Caucasians. The reasons for ethnic variation in IFN-alpha sensitivity are not clear. We speculated that African-American insensitivity to IFN-alpha may be mediated by reduced density of the IFN-alpha receptor (IFN-alphaR) or reduced internalization of the IFN-alpha/IFN-alphaR complex. This speculation was evaluated by comparing binding, uptake and release of 125iodine-labelled IFN-alpha (125I-IFN-alpha) to peripheral blood cells from African-Americans and Caucasians with HCV infection and ethnically matched healthy volunteers. Under various in vitro conditions, binding of 125IFN-alpha to surface receptors was equivalent (P = ns) between African-Americans and Caucasians with HCV infection as well as healthy volunteers (P = ns). Similarly, internalization and release of the 125I-IFN-alpha/IFN-alphaR complex was equivalent (P = ns) between African-Americans and Caucasians with HCV infection and healthy volunteers (P = ns). In addition, ethnicity did not influence (P = ns) IFN-alpha suppression of phytohaemagluttinen induced proliferation. However, IFN-alpha therapy of the same patients showed that African-Americans had lower response rates than Caucasians (14%vs 54%, P < 0.0001). In summary, IFN-alpha resistance among African-Americans is not mediated by intrinsic differences in IFN-alpha receptor density or internalization.


Assuntos
População Negra , Hepatite C Crônica/metabolismo , Interferon-alfa/metabolismo , Leucócitos Mononucleares/metabolismo , População Branca , Células Cultivadas , Feminino , Hepatite C Crônica/sangue , Hepatite C Crônica/etnologia , Humanos , Interferon-alfa/uso terapêutico , Radioisótopos do Iodo , Masculino , Pessoa de Meia-Idade , Receptor de Interferon alfa e beta , Receptores de Interferon/metabolismo
11.
J Med Virol ; 65(3): 510-6, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11596086

RESUMO

Interferon is the primary treatment for hepatitis C virus (HCV). However, the long-term success rate is low particularly for African Americans relative to Caucasians and may be due to differential immune abilities. This study compared cytokine production from PHA-stimulated peripheral blood from 25 healthy and 40 HCV-infected African Americans and Caucasians. HCV patients were designated as IFN responders or nonresponders based on outcome after therapy. Ethnicity and genotype were associated with IFN response. IFN responders were 100% Caucasian, whereas nonresponders were 67% Caucasian and 33% African American (P = 0.01). Genotype 1 was present in 100% nonresponders and 50% responders (P < 0.05). Age, sex, liver histology, ALT, and viral titers were equivalent (ns). Cytokine production from healthy individuals showed ethnic variation in cytokine levels. Healthy African Americans produced greater amounts of IL-2 (P = 0.06), TNF-alpha (P = 0.06) and less IL-10 (P = 0.05) than healthy Caucasians. In contrast, IFN-gamma and TGF-beta levels were equivalent. Pretherapy cytokine production among HCV patients showed a similar pattern of ethnic variation. African American nonresponders produced more IL-2 (P = 0.06) and TNF-alpha (P = 0.02) than Caucasian nonresponders. Cytokine levels among Caucasian and African American nonresponders were equivalent (P = ns) to ethnically matched healthy individuals whereas Caucasian responders produced subnormal levels of IL-10 (P < 0.05) and TGF-beta (P < 0.05). Since all African Americans failed IFN therapy, cytokine production could not be compared with therapeutic outcome. However, comparison of cytokine production among Caucasians showed that responders produced less IL-10 (P < 0.001) and more TGF-beta (P = 0.06) than nonresponders and predicted Caucasian nonresponders with 83% sensitivity and 96% specificity. HCV genotype was not relevant to cytokine production (P = ns). Distribution of cytokine genetic polymorphisms (TNF-alpha, TNF-beta, IL-10, TGF-beta) was equivalent in all ethnic groups and did not predict clinical nonresponders. In summary, it appears that ethnicity may contribute to variable immune responses and therapeutic outcome. The cytokine profile among African Americans suggests a more robust immune response, which may complicate therapy with IFN. In contrast, the subnormal cytokine production among Caucasian responders may be more permissive to IFN therapy. Pretherapy cytokine production may allow prediction of drug resistance among Caucasians.


Assuntos
Antivirais/uso terapêutico , População Negra , Citocinas/biossíntese , Hepatite C/tratamento farmacológico , Interferon-alfa/uso terapêutico , Adulto , Antivirais/farmacologia , Citocinas/genética , Farmacorresistência Viral , Feminino , Hepacivirus/efeitos dos fármacos , Hepatite C/etnologia , Hepatite C/imunologia , Hepatite C/virologia , Humanos , Interferon-alfa/farmacologia , Leucócitos Mononucleares/imunologia , Ativação Linfocitária , Masculino , Polimorfismo Genético , Resultado do Tratamento , População Branca
13.
Antiviral Res ; 48(2): 91-9, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11114411

RESUMO

The improved clinical outcome observed among patients with hepatitis C treated with the combination of alpha interferon (IFN) and ribavirin (RBV) is presumed to result from immunomodulation and viral inhibition. However, the impact of the drug combination upon lymphocyte activity is unknown. The present study evaluated the effects of IFN and RBV, singly and in combination, upon proliferation, cell cycle sensitivity and cytokine elaboration following PHA stimulation of lymphocytes. Two formulations of IFN, interferon-a-2b (IFN-2b) and interferon-a-con-1 (CIFN), were included. Titration of each drug over a wide range of concentrations showed dose dependent proliferative suppression without cytotoxicity. Proliferation was suppressed 57-99% (P<0.001) by IFN-2b (10(5)-10(7) IU/ml), 41-74% (P<0.001) by CIFN (1.5-150 ng/ml), and 10-94% (P<0.001) by RBV (0.5-50 microg/ml). Isobologram analysis showed that the interaction between IFN-2b and RBV on proliferative suppression was additive. In contrast, the interaction between CIFN and RBV was weakly antagonistic. Proliferative suppression by both the IFNs was cell cycle restricted. IFN-2b and CIFN added at the onset of PHA stimulation (G0/G1) versus 24 h later (S phase) inhibited proliferation by 50 versus 5%, respectively (P<0.05). The onset of IFN resistance correlated with a 50% reduction (P<0.05) in IFN receptors on the cell surface. In contrast, RBV caused equivalent proliferative suppression (P=NS) when added at any time during PHA activation. Cytokine secretion after 24 h of PHA stimulation showed that IFN-2b versus CIFN increased the secretion of IL2, TNF and gamma IFN by 4.5-, 4.1- and 8.3-fold (P<0.005) versus 1-, 1.9- and 1.9-fold (P<0.05), respectively, above control levels. Neither IFN affected IL10 secretion. RBV, singly and in combination with IFN, had no impact on cytokine expression (P=NS). This study identifies several potential mechanisms by which the combination of IFN and RBV may exert a more potent effect upon cellular immunity than either agent alone and shows that different formulations of IFN may have non-identical effects upon lymphocyte responses.


Assuntos
Antivirais/farmacologia , Citocinas/biossíntese , Interferon Tipo I/farmacologia , Interferon-alfa/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Ribavirina/farmacologia , Ciclo Celular/efeitos dos fármacos , Células Cultivadas , Sinergismo Farmacológico , Humanos , Interferon alfa-2 , Linfócitos/efeitos dos fármacos , Linfócitos/imunologia , Proteínas Recombinantes , Linfócitos T/imunologia
14.
Transplantation ; 69(11): 2449-51, 2000 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-10868658

RESUMO

BACKGROUND: The impact of influenza vaccination on in vitro parameters of cellular and humoral immunity, anti-viral titers, and clinical outcome was evaluated among cardiac transplant recipients. METHODS: Blood was collected from 29 patients before and 3-4 weeks after influenza vaccination and tested for phenotypic changes in lymphoid subpopulations and generation of antibodies against the allograft and vaccine. RESULTS: Vaccination did not change the percentage of lymphoid subpopulations and did not induce generation of anti-HLA alloantibodies. Anti-vaccine response was detected in 12 of 29 patients and did not correlate with rejection history, length of graft survival, or immunosuppressive therapy. Vaccination did not change the frequency of rejection. Flu-like symptoms were reported in one patient but not confirmed microbiologically. CONCLUSION: Despite the small number of patients in the study, influenza vaccination did not induce undesirable side effects, such as graft rejection or allo-sensitization. Generation of a positive anti-vaccine response was lower among the transplant recipients than healthy volunteers (41% vs. 80%). Clinical efficacy of the vaccine among the responders was not evaluated.


Assuntos
Transplante de Coração/imunologia , Vacinas contra Influenza/efeitos adversos , Idoso , Formação de Anticorpos/efeitos dos fármacos , Rejeição de Enxerto/epidemiologia , Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto/efeitos dos fármacos , Antígenos HLA/imunologia , Humanos , Imunidade Celular/efeitos dos fármacos , Imunossupressores/uso terapêutico , Incidência , Isoanticorpos/imunologia , Subpopulações de Linfócitos/efeitos dos fármacos , Pessoa de Meia-Idade
15.
Transplantation ; 69(7): 1348-52, 2000 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-10798752

RESUMO

BACKGROUND: Antiphospholipid antibody syndrome (APAS) is characterized by the presence of anticardiolipin antibodies (ACA) in association with thrombotic disorders of arterial and/or venus systems, spontaneous abortion(s) or thrombocytopenia. METHODS: In this multicenter study, 502 end-stage renal disease (ESRD) patients awaiting renal transplants were screened to determine the frequency of APAS, the potential risk associated with APAS, and strategies for therapeutic intervention. Ninety-three patients (19%) had high titers of ACA. Twenty-three patients had documented evidence of one or more of the thrombotic disorders such as lupus, frequent abortions, frequent thrombosis of arteriovenous shunts, biopsy-proven microrenal angiopathy, or thrombocytopenia and thus were diagnosed with APAS. Of these 23 patients, 11 received kidney transplants either with (4 patients) or without (7 patients), concomitant anticoagulation therapy. RESULTS: All seven of the patients with APAS not treated with anticoagulation therapy lost their allografts within 1 week as a result of renal thrombosis. In contrast, three out of four transplant patients with APAS treated with anticoagulation therapy maintained their allografts for over 2 years. The fourth patient lost his graft within a week because of thrombosis. Of the remaining 70 patients with high titers of ACA but no evidence of thrombotic disorders, 37 received kidney transplants. None lost their allografts as a result of thrombosis. Our data suggest that, although 19% of our ESRD patients exhibit high titer of ACA, only 5% of the patients have APAS. CONCLUSION: In conclusion, our data suggest that the patients with APAS are at high risk of posttransplant renal thrombosis. Anticoagulation therapy could prevent patients from posttransplant thrombosis in patients with APAS.


Assuntos
Síndrome Antifosfolipídica/complicações , Síndrome Antifosfolipídica/tratamento farmacológico , Falência Renal Crônica/complicações , Falência Renal Crônica/cirurgia , Transplante de Rim , Anticorpos Anticardiolipina/análise , Anticoagulantes/uso terapêutico , Síndrome Antifosfolipídica/epidemiologia , Feminino , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto/efeitos dos fármacos , Humanos , Nefropatias/complicações , Nefropatias/prevenção & controle , Masculino , Prevalência , Fatores de Risco , Trombose/complicações , Trombose/prevenção & controle , Varfarina/uso terapêutico
17.
Transplantation ; 65(3): 444-6, 1998 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-9484770

RESUMO

BACKGROUND: Cytotoxic IgG against class I antigens can contribute to renal dysfunction or failure after transplantation. However, the clinical relevance of IgG measured by flow cytometric cross-matching is controversial. This study correlated pre- and postoperative flow reactivity with clinical outcome among renal transplant patients with negative preoperative cytotoxic cross-matches. METHODS: Nonsensitized primary renal allograft patients (n = 157) with negative preoperative cytotoxic cross-matches (complement-dependent lymphocytotoxicity assays) were stratified on the basis of IgG reactivity measured by flow cytometric cross-matching (FCXM) as FCXM negative (Neg) or positive against class I (T-pos FCXM) or class II (B-pos FCXM) antigens. The groups were compared in terms of frequency of early rejection and 1-year graft survival. RESULTS: Patient distribution was 67% Neg, 14% T-pos FCXM, 14% B-pos FCXM, and 5% IgM FCXM. The incidence of early rejection was 25+/-3% for Neg and 51+/-3% for T- and B-pos FCXM (P < 0.05). One-year graft survival for Neg versus T-pos and B-pos FCXM was 97+/-3% versus 44+/-10% (P < 0.05) and 77+/-5% (P = 0.06), respectively. Rejections requiring plasmapheresis were found only among patients with T-pos FCXM. Among 29 patients, FCXM and complement-dependent lymphocytotoxicity assays were performed 10+/-2 and 28+/-4 days after transplantation. Pre- and posttransplant antibody levels were relatively unchanged among Neg and B-pos FCXM patient groups. In contrast, patients with T-pos FCXM produced cytotoxic IgG against class I after transplantation, which may have contributed to the severe graft dysfunction experienced by this group. CONCLUSIONS: FCXM is a useful tool to stratify primary renal transplant candidates in terms of potential risk for severe rejection. Furthermore, demonstration of preoperative flow reactivity against class I may identify a subgroup of patients at risk for early elaboration of cytotoxic alloantibody.


Assuntos
Citotoxicidade Celular Dependente de Anticorpos , Rejeição de Enxerto/epidemiologia , Teste de Histocompatibilidade/métodos , Imunoglobulina G/biossíntese , Isoanticorpos/biossíntese , Transplante de Rim/imunologia , Linfócitos B/imunologia , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/prevenção & controle , Humanos , Medição de Risco , Linfócitos T/imunologia
18.
Transplantation ; 66(12): 1616-21, 1998 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-9884248

RESUMO

BACKGROUND: The success of liver transplantation in this decade has become the stimulus to extend the donor and recipient pool. Reducing early posttransplant morbidity to maintain our success, as we expand our frontiers, has led us to focus on balanced testing of multidrug immunosuppression regimens. METHODS: A prospective trial in orthotopic liver transplantation using Mycophenolate Mofetil and an identical steroid taper with randomization of patients to Neoral (N) or Tacrolimus (FK) is the basis of this report. This was an intent-to-treat study designed to compare the 6-month primary endpoints of rejection and infection and to compare the 6-month secondary endpoints of liver function, renal function, bone marrow function, hypertension, and serum cholesterol levels. RESULTS: Ninety-seven patients completed the 6-month follow-up period (N=49, FK=48). The actual 6-month patient and graft survival rates were 98% and 94%, respectively. There was no difference in the number of patients with rejection episodes (N=11, FK=8) (P=0.61). There were 24 infections (3 cytomegalovirus) in the FK group and 30 infections (9 cytomegalovirus) in the N group. The cholesterol levels at 6 months were not significantly different (P=0.07) between the groups. The other secondary 6-month endpoints were not significantly different, except total bilirubin, which was lower in the FK arm (P=0.02). CONCLUSIONS: The use of Mycophenolate Mofetil with N or FK and an identical steroid taper after orthotopic liver transplantation is associated with excellent graft and patient survival, and at 6 months, only 191% of the patients experienced rejection, with a 48% overall infection rate.


Assuntos
Ciclosporina/administração & dosagem , Imunossupressores/administração & dosagem , Transplante de Fígado , Ácido Micofenólico/análogos & derivados , Tacrolimo/administração & dosagem , Adolescente , Adulto , Idoso , Colesterol/sangue , Infecções por Citomegalovirus/prevenção & controle , Feminino , Sobrevivência de Enxerto , Humanos , Transplante de Fígado/efeitos adversos , Transplante de Fígado/imunologia , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/administração & dosagem , Estudos Prospectivos , Fatores de Risco
19.
Transplantation ; 63(11): 1685-8, 1997 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-9197367

RESUMO

BACKGROUND: This case report is the first documentation of the occurrence and potential source of lethal graft-versus-host disease (GVHD) after simultaneous kidney-pancreas transplantation. The patient was a 27-year-old African-American male who received an ABO-compatible, five HLA antigen-mismatched kidney-pancreas transplant from a 17-year-old African-American female donor, who died after childbirth. METHODS: Preoperative crossmatches using lymphocytotoxicity and flow cytometry were negative. The patient received four blood transfusions within 10 days of transplantation. Immunosuppression consisted of OKT3 induction, and then cyclosporine, azathioprine, and corticosteroids. RESULTS: On postoperative day (POD) 9, the patient became febrile, and leukocytopenia and pancytopenia developed. Immunosuppression was reduced and granulocyte colony-stimulating factor was begun. Cultures were negative, interleukin 6 and interleukin 8 levels were elevated, and a cutaneous rash appeared on POD 18. A skin biopsy demonstrated dermatitis with focal epidermal necrosis consistent with GVHD. In an attempt to identify the source of GVHD, variable-number tandem repeat analysis fingerprinting was performed with DNA from donor splenocytes, from the skin biopsy, as well as from the patient's buccal mucosa. The skin biopsy showed a mixed variable-number tandem repeat analysis type containing DNA fragments matching the recipient and donor. Blood donors were excluded as a source because they were serologically different from the organ donor. The patient developed liver abnormalities and died from multiorgan failure on POD 22. CONCLUSIONS: We speculate that carryover of passenger donor lymphocytes within the transplanted organ were responsible for GVHD. Furthermore, donor traits such as sexual mismatching, African-American race, and alloimmune status may be important potential risk factors for GVHD.


Assuntos
Doença Enxerto-Hospedeiro/etiologia , Transplante de Rim/efeitos adversos , Transplante de Pâncreas/efeitos adversos , Adolescente , Adulto , Transplante de Medula Óssea/efeitos adversos , Feminino , Teste de Histocompatibilidade , Humanos , Transplante de Fígado/efeitos adversos , Masculino , Doadores de Tecidos
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