Asunto(s)
Anticuerpos/sangre , Anticoagulantes/inmunología , Puente Cardiopulmonar , Antagonistas de Heparina/inmunología , Antagonistas de Heparina/uso terapéutico , Heparina/inmunología , Activación Plaquetaria/inmunología , Protaminas/inmunología , Protaminas/uso terapéutico , Femenino , Humanos , MasculinoRESUMEN
OBJECTIVES: Platelet-activating antibodies against protamine-heparin-complexes were described in patients undergoing cardiac surgery, but their clinical consequences remain unclear. This prospective single-center observational study aimed to describe the prevalence and clinical consequences of protamine-heparin-complex antibodies in patients undergoing cardiac surgery with cardiopulmonary bypass. METHODS: A total of 200 patients undergoing cardiac surgery with cardiopulmonary bypass were included. Blood samples were collected preoperatively and 1 hour, 24 hours, and 7 days after weaning from cardiopulmonary bypass. All sera were tested for the presence of protamine-heparin-complex antibodies using a modified heparin-induced platelet-activation assay. Specific Fcγ receptor IIa-dependent platelet activation was confirmed by repeated testing in the presence of the Fcγ receptor IIa-blocking antibody IV.3. RESULTS: Samples from 185 patients were obtained, of whom 24 patients (13%) were positive for protamine-heparin-complex antibodies preoperatively. In all positive samples, functional reactivity was reversible in the presence of IV.3. Although patients with a preoperative presence of protamine-heparin-complex antibodies were significantly older compared with patients negative for protamine-heparin-complex antibodies (73 ± 9.8 years vs 68 ± 10 years, P = .037), no other potential risk factors were identified at 1 day before operation. Patients with protamine-heparin-complex antibodies required significantly more protamine to neutralize heparin (47.66 mg vs 41.67 mg, P = .027). Protamine-heparin-complex antibodies have no significant influence on perioperative platelet numbers, bleeding complications, transfusion requirement, thromboembolic events, major cardiovascular and cerebrovascular events, inflammation parameters, or kidney function. CONCLUSIONS: Protamine-heparin-complex antibodies occur frequently in patients undergoing cardiac surgery on cardiopulmonary bypass, resulting in specific platelet activation in vitro. Protamine-heparin-complex antibodies are associated with increased protamine requirement after cardiopulmonary bypass and possibly slower recovery of platelet numbers.
Asunto(s)
Anticuerpos/sangre , Anticoagulantes/inmunología , Puente Cardiopulmonar , Antagonistas de Heparina/inmunología , Antagonistas de Heparina/uso terapéutico , Heparina/inmunología , Activación Plaquetaria/inmunología , Protaminas/inmunología , Protaminas/uso terapéutico , Anciano , Femenino , Humanos , Masculino , Estudios ProspectivosRESUMEN
Protamine is routinely used to reverse heparin anticoagulation during cardiopulmonary bypass (CPB). Heparin interacts with protamine to form ultralarge complexes that are immunogenic in mice. We hypothesized that patients exposed to protamine and heparin during CPB will develop antibodies (Abs) to protamine/heparin (PRT/H) complexes that are capable of platelet activation. Specimens from a recently completed prospective clinical trial (HIT [for heparin-induced thrombocytopenia] 5801 study; n = 500) of CPB patients were examined for PRT/H Abs at baseline, at time of hospital discharge (between days 3 through 7), and 30 days after CPB. PRT/H antibody features were characterized and correlated with adverse cardiovascular outcomes. We found a high incidence of PRT/H antibody formation (29%) in patients undergoing cardiac surgery. PRT/H Abs were of high titer (mean titer 1:14,744), showed heparin-dependent binding, and activated platelets in the presence of protamine. PRT/H Abs showed no cross-reactivity to platelet factor 4/heparin complexes, but were cross-reactive with protamine-containing insulin preparations. In the absence of circulating antigen at day 30, there were no complications of thrombocytopenia, thrombotic events, or long-term cardiovascular events. These studies show that Abs to PRT/H occur commonly after cardiac bypass surgery, share a number of serologic features with HIT Abs, including platelet activation, and may pose health risks to patients requiring drug reexposure.
Asunto(s)
Anticuerpos/sangre , Puente Cardiopulmonar , Heparina/inmunología , Protaminas/inmunología , Anciano , Anticoagulantes/administración & dosificación , Anticoagulantes/efectos adversos , Anticoagulantes/inmunología , Reacciones Cruzadas/inmunología , Ensayo de Inmunoadsorción Enzimática , Femenino , Heparina/administración & dosificación , Heparina/efectos adversos , Antagonistas de Heparina/administración & dosificación , Antagonistas de Heparina/inmunología , Humanos , Incidencia , Insulina Isófana/inmunología , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Evaluación de Resultado en la Atención de Salud , Factor Plaquetario 4/inmunología , Protaminas/administración & dosificación , Unión Proteica/inmunología , Trombocitopenia/inducido químicamente , Trombocitopenia/epidemiología , Trombocitopenia/inmunología , Factores de TiempoRESUMEN
Protamine, which is routinely used after cardiac surgery to reverse the anticoagulant effects of heparin, is known to be immunogenic. Observing patients with an otherwise unexplained rapid decrease in platelet count directly after protamine administration, we determined the incidence and clinical relevance of protamine-reactive antibodies in patients undergoing cardiac-surgery. In vitro, these antibodies activated washed platelets in a FcγRIIa-dependent fashion. Using a nonobese diabetic/severe combined immunodeficiency mouse model, those antibodies induced thrombocytopenia only when protamine and heparin were present but not with protamine alone. Of 591 patients undergoing cardiopulmonary bypass surgery, 57 (9.6%) tested positive for anti-protamine-heparin antibodies at baseline and 154 (26.6%) tested positive at day 10. Diabetes was identified as a risk factor for the development of anti-protamine-heparin antibodies. In the majority of the patients, these antibodies were transient and titers decreased substantially after 4 months (P < .001). Seven patients had platelet-activating, anti-protamine-heparin antibodies at baseline and showed a greater and more prolonged decline in platelet counts compared with antibody-negative patients (P = .003). In addition, 2 of those patients experienced early arterial thromboembolic complications vs 9 of 584 control patients (multivariate analysis: odds ratio, 21.58; 95% confidence interval, 2.90-160.89; P = .003). Platelet-activating anti-protamine-heparin antibodies show several similarities with anti-platelet factor 4-heparin antibodies and are a potential risk factor for early postoperative thrombosis.
Asunto(s)
Anticuerpos/sangre , Heparina/inmunología , Protaminas/inmunología , Trombocitopenia/inmunología , Anciano , Animales , Puente Cardiopulmonar , Femenino , Heparina/administración & dosificación , Heparina/efectos adversos , Antagonistas de Heparina/administración & dosificación , Antagonistas de Heparina/efectos adversos , Antagonistas de Heparina/inmunología , Humanos , Técnicas para Inmunoenzimas , Inmunoglobulina G/sangre , Incidencia , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Persona de Mediana Edad , Recuento de Plaquetas , Factor Plaquetario 4/inmunología , Transfusión de Plaquetas/métodos , Protaminas/administración & dosificación , Trombocitopenia/inducido químicamente , Trombocitopenia/epidemiología , Factores de Tiempo , Trasplante HeterólogoAsunto(s)
Hipersensibilidad a las Drogas/prevención & control , Hipersensibilidad a los Alimentos/diagnóstico , Antagonistas de Heparina , Perciformes , Protaminas , Animales , Puente de Arteria Coronaria/métodos , Hipersensibilidad a las Drogas/diagnóstico , Antagonistas de Heparina/inmunología , Humanos , Inmunoglobulina E/sangre , Complicaciones Intraoperatorias/prevención & control , Masculino , Persona de Mediana Edad , Monitoreo Intraoperatorio/métodos , Protaminas/inmunologíaRESUMEN
Protamine sulphate/DNA complexes have been shown to protect DNA from DNase digestion in a lipid system for gene transfer. A DNA-based vaccine complexed to protamine sulphate was used to induce an immune response against Schistosoma mansoni anchored-glycosylphosphatidylinositol tegumental antigen in BALB/c mice. The protection elicited ranged from 33 to 44%. The spectrum of the elicited immune response induced by the vaccine formulation without protamine was characterized by a high level of IgG (IgG1> IgG2a). Protamine sulphate added to the DNA vaccine formulation retained the green fluorescent protein encoding-plasmid longer in muscle and spleen. The experiments in vivo showed that under protamine sulphate effect, the scope of protection remained unchanged, but a modulation in antibody production (IgG1= IgG2a) was observed.
Asunto(s)
Anticuerpos Antihelmínticos/inmunología , Antígenos Helmínticos/inmunología , Glicosilfosfatidilinositoles/inmunología , Antagonistas de Heparina/inmunología , Protaminas/inmunología , Schistosoma mansoni/inmunología , Vacunas de ADN/inmunología , Animales , Anticuerpos Antihelmínticos/sangre , Antígenos Helmínticos/administración & dosificación , Femenino , Glicosilfosfatidilinositoles/administración & dosificación , Antagonistas de Heparina/administración & dosificación , Inmunoglobulina G/inmunología , Ratones , Ratones Endogámicos BALB C , Protaminas/administración & dosificación , Esquistosomiasis mansoni/prevención & control , Factores de Tiempo , Vacunas de ADN/administración & dosificaciónRESUMEN
Protamine sulphate/DNA complexes have been shown to protect DNA from DNase digestion in a lipid system for gene transfer. A DNA-based vaccine complexed to protamine sulphate was used to induce an immune response against Schistosoma mansoni anchored-glycosylphosphatidylinositol tegumental antigen in BALB/c mice. The protection elicited ranged from 33 to 44 percent. The spectrum of the elicited immune response induced by the vaccine formulation without protamine was characterized by a high level of IgG (IgG1> IgG2a). Protamine sulphate added to the DNA vaccine formulation retained the green fluorescent protein encoding-plasmid longer in muscle and spleen. The experiments in vivo showed that under protamine sulphate effect, the scope of protection remained unchanged, but a modulation in antibody production (IgG1= IgG2a) was observed.
Asunto(s)
Animales , Femenino , Ratones , Anticuerpos Antihelmínticos/inmunología , Antígenos Helmínticos/inmunología , Glicosilfosfatidilinositoles/inmunología , Antagonistas de Heparina/inmunología , Protaminas/inmunología , Schistosoma mansoni/inmunología , Vacunas de ADN/inmunología , Anticuerpos Antihelmínticos/sangre , Antígenos Helmínticos/administración & dosificación , Glicosilfosfatidilinositoles/administración & dosificación , Antagonistas de Heparina/administración & dosificación , Inmunoglobulina G/inmunología , Ratones Endogámicos BALB C , Protaminas/administración & dosificación , Esquistosomiasis mansoni/prevención & control , Factores de Tiempo , Vacunas de ADN/administración & dosificaciónRESUMEN
A new thirteen amino acid peptide, named low molecular weight protamine (LMWP), was obtained through the enzymatic digestion of native protamine. Both in vitro and in vivo results showed that LMWP fully maintained the heparin neutralization function of protamine but had much lower immunogenicity and antigenicity. Unlike protamine, neither LMWP nor LMWP/heparin complexes caused significant blood platelet aggregation in rats. These results suggest that LMWP can be used as a substitute for protamine for developing a new generation of nontoxic heparin antagonists.
Asunto(s)
Antagonistas de Heparina/química , Antagonistas de Heparina/farmacología , Heparina/metabolismo , Protaminas/farmacología , Animales , Antígenos/inmunología , Femenino , Antagonistas de Heparina/efectos adversos , Antagonistas de Heparina/inmunología , Ratones , Protaminas/efectos adversos , Protaminas/química , Protaminas/inmunología , Ratas , Ratas Sprague-Dawley , Factores de TiempoAsunto(s)
Puente Cardiopulmonar , Hipersensibilidad a las Drogas/diagnóstico , Peces , Hipersensibilidad a los Alimentos/etiología , Antagonistas de Heparina/inmunología , Protaminas/inmunología , Anciano , Animales , Anticoagulantes/administración & dosificación , Puente Cardiopulmonar/instrumentación , Materiales Biocompatibles Revestidos , Puente de Arteria Coronaria , Reacciones Cruzadas , Hipersensibilidad a los Alimentos/diagnóstico , Implantación de Prótesis de Válvulas Cardíacas , Heparina/administración & dosificación , Antagonistas de Heparina/efectos adversos , Humanos , Masculino , Cuidados Preoperatorios , Protaminas/efectos adversos , Pruebas CutáneasRESUMEN
Adverse responses to protamine sulfate have been identified for many years. The antigen-antibody response to protamine sulfate results in a type I anaphylactic reaction. Manifestations of allergic reactions include hypotension, bronchospasm, and skin and mucous membrane reactions. The severity of the adverse responses may vary from mild to causing death. Several potential risk factors for adverse reactions to protamine have been identified, including insulin-dependent diabetes mellitus, vasectomy, allergy to fish, prior exposure to protamine sulfate, and the rate of infusion. A case study is presented, and strategies for improving patient outcomes are discussed.
Asunto(s)
Anafilaxia/inducido químicamente , Antagonistas de Heparina/efectos adversos , Protaminas/efectos adversos , Anciano , Anafilaxia/terapia , Reacciones Antígeno-Anticuerpo , Femenino , Antagonistas de Heparina/inmunología , Humanos , Protaminas/inmunología , Factores de RiesgoRESUMEN
We have produced a panel of monoclonal antibodies (mAbs) against rabbit platelet factor 4 (PF4). Two of these mAbs have been characterized in this study. In particular the antibody called 10B2, which also recognizes the human molecule, is able to block PF4's ability to neutralize heparin in a modified Heparin-Factor Xa chromogenic assay. The inhibition appears to be more than 95% at 1:1 mAb/PF4 molar ratio both for purified rabbit and human PF4. Similar results were obtained using supernatants from stimulated human platelets (90% of inhibition at 1:1 mAb/PF4 molar ratio) or using Fab fragments from 10B2. Studies to determine the antigenic determinant against which 10B2 is directed, show that this is an assembled epitope which involves disulfide bonds of the PF4.