RESUMO
BACKGROUND: TSH and ACTH are crucial hormones for diagnosing thyroid and adrenal diseases, and incorrect test reports can cause significant harm to patients. METHODS: The TSH and ACTH levels on the testing system of our laboratory were measured using "sandwich" assays. The patient had heterophilic antibodies in their body, causing a false increase in TSH and ACTH levels. RESULTS: TSH on the Abbott platform was 59.7 µIU/mL and on the Roche platform it was 4.33 µIU/mL. After pretreatment with HBR it was 3.95 µIU/mL; ACTH on the SIEMENS platform was 263.5 pg/mL, on the Abbott platform it was 47.6 pg/mL. After pretreatment with HBR it was 36.5 pg/mL. CONCLUSIONS: The patient's serum contains heterophilic antibodies, which interfere with the TSH and ACTH tested by this method.
Assuntos
Hormônio Adrenocorticotrópico , Anticorpos Heterófilos , Tireotropina , Humanos , Masculino , Pessoa de Meia-Idade , Hormônio Adrenocorticotrópico/sangue , Hormônio Adrenocorticotrópico/imunologia , Anticorpos Heterófilos/sangue , Anticorpos Heterófilos/imunologia , Tireotropina/sangue , Tireotropina/imunologiaRESUMO
Recent clinical xenotransplantation and human decedent studies demonstrate that clinical hyperacute rejection of genetically engineered porcine organs can be reliably avoided but that antibody mediated rejection (AMR) continues to limit graft survival. We previously identified porcine glycans and proteins which are immunogenic after cardiac xenotransplantation in non-human primates, but the clinical immune response to antigens present in glycan depleted triple knockout (TKO) donor pigs is poorly understood. In this study we use fluorescence barcoded human embryonic kidney cells (HEK) and HEK cell lines expressing porcine glycans (Gal and SDa) or proteins (tetraspanin-29 [CD9], membrane cofactor protein [CD46], protectin, membrane attack complex inhibition factor [CD59], endothelial cell protein C receptor, and Annexin A2) to screen antibody reactivity in human serum from 160 swine veterinarians, a serum source with potential occupational immune challenge from porcine tissues and pathogens. High levels of anti-Gal IgM were present in all samples and lower levels of anti-SDa IgM were present in 41% of samples. IgM binding to porcine proteins, primarily CD9 and CD46, previously identified as immunogenic in pig to non-human primate cardiac xenograft recipients, was detected in 28 of the 160 swine veterinarian samples. These results suggest that barcoded HEK cell lines expressing porcine protein antigens can be useful for screening human patient serum. A comprehensive analysis of sera from clinical xenotransplant recipients to define a panel of commonly immunogenic porcine antigens will likely be necessary to establish an array of porcine non-Gal antigens for effective monitoring of patient immune responses and allow earlier therapies to reverse AMR.
Assuntos
Rejeição de Enxerto , Transplante Heterólogo , Animais , Transplante Heterólogo/métodos , Humanos , Suínos , Rejeição de Enxerto/imunologia , Células HEK293 , Médicos Veterinários , Polissacarídeos/imunologia , Animais Geneticamente Modificados , Anticorpos Heterófilos/imunologia , Anticorpos Heterófilos/sangue , Xenoenxertos/imunologia , Imunoglobulina M/imunologia , Imunoglobulina M/sangueRESUMO
BACKGROUND: Heterophilic antibodies (HA) are one of the main substances that interfere with immunology, especially chemiluminescence immunoassay. Non-specific binding, labeling antibodies, bridging to capture antibodies, or labeling antigens can interfere with the detection process, leading to serious discrepancies between the measured results and clinical manifestations, and even delaying clinical diagnosis and treatment. METHODS: This paper is a case of epidemic hemorrhagic fever causing pseudo CEA elevation caused by heterophagy induced antibodies in the body. RESULTS: The patient's CEA detected on the ABBOTT detection platform was 51.1 ng/mL, and on the ROCHE detection platforms it was 4.66 ng/mL, and treated by PEG precipitation it was 45.2 ng/mL, after diluting the sample the CEA was 50.2 ng/mL, meanwhile the patient's platelets were 96 x 109/L and serum creatinine was 188.4 µmol/L, epidemic hemorrhagic fever IgM antibody was positive. CONCLUSIONS: When the test results do not match clinical symptoms, further confirmation is required through additional testing. Patients who use mouse monoclonal antibody preparations for diagnosis or treatment may have human anti-mouse antibodies in their serum, and the test results may falsely increase or decrease.
Assuntos
Antígeno Carcinoembrionário , Humanos , Anticorpos Heterófilos/sangue , Anticorpos Heterófilos/imunologia , Antígeno Carcinoembrionário/sangue , Imunoglobulina M/sangue , Feminino , IdosoRESUMO
BACKGROUND: There are many methods for the detection of D-dimer in clinical laboratories. Immunoturbidimetric assays are widely used because of its high sensitivity and specificity [1-3]. However, this method may be affected by the interference of rheumatoid factor (RF), heterophilic antibodies, and other unknown proteins, and its falsity will increase, thus affecting clinical diagnosis. METHODS: This paper reports the cause analysis of a case of spurious D-dimer increase and four corresponding elimination methods: double dilution of the original specimen, detection of fibrin degradation product (FDP) level, addition of heterophilic blocking reagent, and comparison between different instruments. RESULTS: It was confirmed that there were special antibodies in the patient's body by four methods, which had non-specific reactions with D-dimer reagents, resulting in false increases of results. CONCLUSIONS: When the coagulation function results of patients show isolated increases in D-dimer, or the results are inconsistent with clinical symptoms, laboratory personnel should consider the possibility of interference factors, and conduct effective treatment to obtain correct test results, and thus reduce the occurrence of medical adverse events caused by inaccurate test results.
Assuntos
Produtos de Degradação da Fibrina e do Fibrinogênio , Humanos , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Reações Falso-Positivas , Imunoturbidimetria/métodos , Feminino , Masculino , Anticorpos Heterófilos/sangue , Fator Reumatoide/sangueRESUMO
Heterophile antibody assays have been used to aid the diagnosis of infectious mononucleosis caused by the Epstein-Barr virus. Seven commercially available assays currently widely utilized in clinical laboratories were compared in this study. Variable performance characteristics and assay times are observed, and these pieces of data may assist clinical laboratories in assay selection and result interpretation.
Assuntos
Anticorpos Heterófilos/sangue , Anticorpos Antivirais/sangue , Técnicas de Laboratório Clínico/normas , Infecções por Vírus Epstein-Barr/diagnóstico , Mononucleose Infecciosa/diagnóstico , Mononucleose Infecciosa/imunologia , Kit de Reagentes para Diagnóstico/normas , Adolescente , Anticorpos Heterófilos/imunologia , Criança , Técnicas de Laboratório Clínico/métodos , Infecções por Vírus Epstein-Barr/sangue , Humanos , Imunoglobulina M/sangue , Mononucleose Infecciosa/sangue , Adulto JovemRESUMO
Xenotransplantation, using genetically-modified pigs for clinical organ transplantation, is a solution to the organ shortage. The biggest barrier to clinical implementation is the antigenicity of pig cells. Humans possess preformed antibody to pig cells that initiate antibody-mediated rejection of pig organs in primates. Advances in genetic engineering have led to the development of a pig lacking the three known glycan xenoantigens (triple-knockout [TKO] pigs). A significant number of human sera demonstrate no antibody binding to TKO pig cells. As a result of the TKO pig's low antigen expression, survival of life-supporting pig organs in immunosuppressed nonhuman primates has significantly increased, and hope has been renewed for clinical trials of xenotransplantation. It is important to understand the context in which xenotransplantation's predecessor, allotransplantation, has been successful, and the steps needed for the success of xenotransplantation. Successful allotransplantation has been based on two main immunological approaches - (i) adequate immunosuppressive therapy, and (ii) careful histocompatibility matching. In vivo studies suggest that the available immunosuppressive regimens are adequate to suppress the human anti-pig cellular response. Methods to evaluate and screen patients for the first clinical xenotransplantation trial are the next challenge. The goal of this review is to summarize the history of histocompatibility testing, and the available tools that can be utilized to determine xenograft histocompatibility.
Assuntos
Antígenos Heterófilos/genética , Antígenos HLA/genética , Antígenos de Histocompatibilidade Classe I/genética , Teste de Histocompatibilidade/métodos , Polissacarídeos/genética , Transplante Heterólogo , Animais , Animais Geneticamente Modificados , Anticorpos Heterófilos/sangue , Antígenos Heterófilos/imunologia , Células Cultivadas , Técnicas de Inativação de Genes , Histocompatibilidade , Humanos , Polissacarídeos/imunologia , Suínos , Obtenção de Tecidos e ÓrgãosRESUMO
BACKGROUND: Heterophilic antibodies in serum and plasma can interfere with mammalian antibodies in immunoassays and result in false test results, usually false positive. Although studies screening for heterophilic antibodies as well as elimination studies have been conducted in dogs and cats, knowledge of the presence of heterophilic antibodies in other species in veterinary medicine is limited. In this study, a 2-site sandwich-type interference assay that detects anti-mouse antibodies was used to detect heterophilic antibodies in a population of horses treated in an animal hospital. RESULTS: A total of 194 serum samples from 127 individual horses were analyzed. There were 11/127 (8.7%) interference-positive horses, and these were analyzed in an assay exchanging the capture mouse IgG with chicken IgY. The positive samples were negative in the chicken IgY assay, indicating elimination of a possible interference, with the chicken-based assay. Four interference-positive samples were from geldings, and anti-Müllerian hormone (AMH) was analyzed from these samples. AMH concentrations were negative in these samples as expected in geldings, indicating that the heterophilic antibodies did not cause interference in the AMH assay. CONCLUSION: The present study shows that there are heterophilic antibodies in horse serum samples like in samples from humans, dogs, and cats. The use of chicken-based reagents, such as chicken IgY, which do not cross-react with mammalian IgG, eliminates the effects of interfering antibodies in the samples. Equine heterophilic antibodies do not necessarily cause interference in commercial immunoassays.
Assuntos
Anticorpos Heterófilos/sangue , Doenças dos Cavalos/imunologia , Animais , Galinhas , Ensaio de Imunoadsorção Enzimática/veterinária , Cavalos , Imunoensaio/veterinária , Imunoglobulina G , Imunoglobulinas , Camundongos , PrevalênciaRESUMO
Advances in genetic engineering, particularly CRISPR/Cas9, have resulted in the development of a triple glycan-knockout (TKO) pig. There is minimal human antipig antibody binding to TKO pig cells. The TKO background has decreased antibody binding to a sufficiently low level that any additional xenoantigens expressed on the cells can now be more easily detected. One of these xenoantigens is the swine major histocompatibility complex, termed swine leukocyte antigens (SLA). SLA are the homolog to HLAs, a protein complex expressed on human tissue capable of stimulating the development of new antibodies in allotransplantation. These antibodies can result in graft failure through hyperacute, acute, or chronic rejection. Our knowledge of SLA, particularly in the last 5 years, has grown considerably. The presence, cause, and methods to detect anti-SLA antibodies will need to be carefully considered for the first clinical trial of xenotransplantation. The focus of this review is to summarize the role of SLA in xenotransplantation and consider whether it will prove to be a major barrier. Techniques are now available to mutate target SLA amino acids to ensure that cross-reactive anti-HLA antibodies no longer bind to SLA on the cells of the organ-source pigs. While deletion of SLA expression is possible, it would render the pig at risk for infectious complications. The ideal organ-source pig for HLA highly sensitized recipients may therefore be 1 with site-specific mutations to eliminate cross-reactive binding.
Assuntos
Anticorpos Heterófilos/sangue , Antígenos Heterófilos/imunologia , Rejeição de Enxerto/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Sus scrofa/imunologia , Transplante Heterólogo , Animais , Animais Geneticamente Modificados , Especificidade de Anticorpos , Antígenos Heterófilos/genética , Rejeição de Enxerto/sangue , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Especificidade da Espécie , Sus scrofa/genética , Tolerância ao Transplante , Transplante Heterólogo/efeitos adversosRESUMO
BACKGROUND: Natural preformed anti-pig IgM/IgG antibodies in primates play an important role in xenograft rejection. As it is not clear how IgE and IgA engage in the immune system in xenotransplantation, we investigated natural preformed and elicited anti-pig IgE/IgA in naive primates and after xenotransplantation in nonhuman primates. METHODS: The binding of IgM/IgG/IgE/IgA antibodies to red blood cells (RBCs) from wild-type (WT), α1,3-galactosyltransferase gene-knockout (GTKO), and GTKO/cytidine monophospho-N-acetylneuraminic acid hydroxylase gene-knockout/ß-1,4 N-acetylgalactosaminyltransferase 2 gene-knockout (ie, triple-knockout pigs) pigs were measured by flow cytometry in naive human (n = 50) and baboon (n = 14) sera. Antibody binding to WT and GTKO pig RBCs (pRBCs) was also measured in the sera of baboons (nonsensitized n = 7, sensitized n = 2) and rhesus monkeys (nonsensitized n = 2, sensitized n = 11) following WT or GTKO pig organ/tissue xenotransplantation. Deposition of IgM/IgG/IgE/IgA in the grafts was detected by immunohistochemistry. RESULTS: The majority of humans had natural preformed IgM/IgG/IgE/IgA to WT and GTKO pRBCs. In contrast, IgM/IgG/IgE/IgA to triple-knockout pRBCs were present at lower levels and frequency (P < 0.01). Baboons also had IgM/IgG/IgE/IgA antibodies against WT pRBCs, but fewer to GTKO and triple-knockout (P < 0.01). After xenotransplantation into nonhuman primates, when IgM/IgG increased, IgE/IgA also increased, but to a lesser extent. In addition to IgM/IgG, IgE or IgA deposition was observed in rejected pig xenografts. CONCLUSIONS: Primates develop serum anti-pig IgE/IgA antibodies both naturally and during xenograft rejection. The pathophysiological role, if any, of anti-pig IgE/IgA antibodies remains unknown.
Assuntos
Anticorpos Heterófilos/sangue , Eritrócitos/imunologia , Rejeição de Enxerto/imunologia , Imunoglobulina A/sangue , Imunoglobulina E/sangue , Transplante Heterólogo/efeitos adversos , Animais , Animais Geneticamente Modificados , Galactosiltransferases/genética , Galactosiltransferases/imunologia , Rejeição de Enxerto/sangue , Rejeição de Enxerto/patologia , Humanos , Macaca mulatta , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/imunologia , N-Acetilgalactosaminiltransferases/genética , N-Acetilgalactosaminiltransferases/imunologia , Papio , Especificidade da Espécie , Sus scrofa/genética , Sus scrofa/imunologiaRESUMO
Stress and leg weakness are detrimental to broiler production, health, and welfare. Traditional methods to evaluate stress may be stressful to the bird because they are invasive and require handling and restraint. Two studies examined the effects of light intensity and flooring on the following in broilers: 1) traditional methods for assessing stress using heterophil-to-lymphocyte ratios and serum corticosterone (CORT) concentrations, 2) noninvasive measures of stress from infrared thermography (IRT) eye and beak surface temperatures, and 3) latency-to-lie (LTL) test times of birds tested individually and in groups of 5. Day-of-hatch male broiler chicks were placed into 6 pens (N = 120 chicks/pen). At 1 wk, pens were allocated to 3 light intensity treatments (2, 5, or 10 lux). At 4 wk, half of the birds from each pen were moved to a pen with wire flooring and the same light intensity. At 1, 4, 5, and 8 wk, blood samples were collected and IRT images of the heads of 5 clinically healthy broilers from each pen were captured. In study 2, IRT images of the heads of birds that became lame in the wire flooring pens were taken. There were no treatment effects on the LTL times of birds tested in groups or individually (P > 0.05). On day 56 in study 1, birds on wire flooring had elevated heterophil-to-lymphocyte ratios and CORT concentrations (P ≤ 0.002) and depressed IRT eye and beak temperatures (P < 0.0001). In both studies, there were negative correlations between CORT concentrations and IRT beak surface temperatures (P < 0.05). Lame birds had lower IRT eye and beak surface temperatures than sound birds (P ≤ 0.004), and the IRT beak surface temperatures of lame birds were lower than their eye surface temperatures (P = 0.004) in study 2. These studies indicate that the IRT surface temperatures of the eye, and more distinctly of the beak, can be used as sensitive noninvasive indicators of stress.
Assuntos
Galinhas/fisiologia , Abrigo para Animais/classificação , Coxeadura Animal/fisiopatologia , Iluminação , Doenças das Aves Domésticas/fisiopatologia , Animais , Anticorpos Heterófilos/sangue , Corticosterona/sangue , Pisos e Cobertura de Pisos/classificação , Membro Posterior/fisiopatologia , Luz , Linfócitos/metabolismo , Masculino , Estresse Fisiológico , Termografia/veterináriaRESUMO
BACKGROUND: Prolonged use of corticosteroids continues to be the mainstay in the management of most proteinuric glomerulopathies, but is limited by extensive side effects. Alternative medications such as adrenocorticotropic hormone (ACTH) have been recently used to treat refractory glomerulopathies and have shown superior outcomes when compared with steroids. However, the clinical responsiveness to ACTH therapy varies considerably with a number of patients exhibiting de novo or acquired resistance. The underlying mechanism remains unknown. METHODS: A patient with steroid-dependent focal segmental glomerulosclerosis (FSGS) developed severe steroid side effects impacting quality of life and was converted to repository porcine ACTH therapy. Immediate response in the form of remission of nephrotic syndrome was noted followed by relapse in 10 weeks. Suspecting the role of some ACTH-antagonizing factors, the patient's serum was examined. RESULTS: Immunoblot-based antibody assay revealed high titers of de novo IgG antibodies in the patient's serum that were reactive to the porcine corticotropin with negligible cross-reactivity to human corticotropin. In vitro, in cultured B16 melanoma cells that express abundant melanocortin receptors, addition of the patient's serum substantially abrogated the porcine corticotropin triggered signaling activity of the melanocortinergic pathway, marked by phosphorylation of glycogen synthase kinase 3ß, thus suggesting a mitigating effect on the biological functionality of porcine corticotropin. CONCLUSION: ACTH is a useful alternative therapeutic modality for refractory proteinuric glomerulopathies like FSGS. However, as quintessential therapeutic biologics, natural ACTH, regardless of purity and origin, is inevitably antigenic and may cause the formation of neutralizing antibodies in some sensitive patients, followed by resistance to ACTH therapy. It is imperative to develop ACTH analogues with less immunogenicity for improving its responsiveness in patients with glomerular diseases.
Assuntos
Hormônio Adrenocorticotrópico/imunologia , Anticorpos Heterófilos/sangue , Anticorpos Neutralizantes/sangue , Glucocorticoides/farmacologia , Síndrome Nefrótica/tratamento farmacológico , Hormônio Adrenocorticotrópico/análogos & derivados , Hormônio Adrenocorticotrópico/uso terapêutico , Adulto , Animais , Anticorpos Heterófilos/imunologia , Anticorpos Neutralizantes/imunologia , Biópsia , Doença Crônica , Resistência a Medicamentos , Substituição de Medicamentos , Feminino , Glucocorticoides/uso terapêutico , Humanos , Rim/imunologia , Rim/patologia , Síndrome Nefrótica/sangue , Síndrome Nefrótica/diagnóstico , Síndrome Nefrótica/imunologia , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Recidiva , Indução de Remissão/métodos , SuínosRESUMO
Identifying analytical interference is a challenge for the medical biologist in providing advice to the prescriber. Indeed, these analytical interferences often have deleterious consequences on the care of patients. Understanding their mechanisms and mastering corrective procedures is essential to limit these management errors. Faced with the many questions from clinicians in current practice, we propose an algorithm for managing a sample when interference is suspected.
Assuntos
Algoritmos , Artefatos , Árvores de Decisões , Testes Imunológicos , Anticorpos Heterófilos/efeitos adversos , Anticorpos Heterófilos/análise , Anticorpos Heterófilos/sangue , Técnicas de Laboratório Clínico/normas , Reações Falso-Positivas , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Imunoensaio/métodos , Imunoensaio/normas , Testes Imunológicos/métodos , Testes Imunológicos/normas , Guias de Prática Clínica como Assunto , Erro Científico ExperimentalRESUMO
In this report we evaluated a diagnostic algorithm, proposed by the Belgian Superior Health Council, to detect acute and past Epstein-Barr virus (EBV) infections by means of serology in donors of human body material for transplantation. The available EBV serology parameters were tested on eighty serum samples on three random access analysers: Architect i2000 SR, Liasion XL and BioPlex 2200. The EBV sero-status was determined according to the proposed algorithm and results were compared between the different analysers. Seventy one % of the samples gave concordant interpretations on the three analysers. Most of the discordant results were attributable to early antigen (EA) IgG. The knowledge of the EA IgG and heterophile antibodies (HA) IgM status provided only limited added value and was only useful to distinguish between a very early acute infection and false positivity of viral capsid antigen IgM. The diagnostic algorithm proposed by the Belgian Superior Health Council is merely directive and each individual lab remains responsible for the interpretation and implementation of test combinations for the detection of EBV infections. Our study shows the limited added value of testing for EA IgG and HA IgM, based both on clinical and technical performance.
Assuntos
Anticorpos Heterófilos/sangue , Infecções por Vírus Epstein-Barr/diagnóstico , Herpesvirus Humano 4/isolamento & purificação , Imunoglobulina G/sangue , Anticorpos Heterófilos/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Antígenos Virais/sangue , Antígenos Virais/imunologia , Infecções por Vírus Epstein-Barr/sangue , Herpesvirus Humano 4/imunologia , Humanos , Imunoglobulina G/imunologia , Testes Sorológicos , Doadores de TecidosRESUMO
BACKGROUND: Measurement of serum anti-pig antibodies is an important parameter in immune monitoring after pig-to-nonhuman primate xenotransplantation. Pig aortic endothelial cells (pAECs) are commonly used for this purpose. However, human (h) CTLA4-Ig (abatacept/belatacept) could bind to pCD80/86 on the cells, and a secondary antibody (i.e., anti-human IgG) may recognize hCTLA4-Ig (in the absence of serum anti-pig IgG antibody binding to pAECs), potentially leading to misinterpretation of the results. Our aim was to determine whether hCTLA4-Ig binding to pAECs is associated with false-positive results. METHODS: Sera were obtained from (i) naïve baboons (nâ¯=â¯3) and (ii) baboons (nâ¯=â¯2) that had undergone pig artery patch transplantation with/without hCTLA4Ig therapy. Serum IgM and IgG binding to (i) AECs, (ii) red blood cells (RBCs), and (iii) CD3+T cells in peripheral blood mononuclear cells (PBMCs) from an α1,3-galactosyltransferase gene-knockout pig expressing human CD46 (GTKO/hCD46) was measured by flow cytometry in the presence or absence of hCTLA-4Ig. Complement-dependent cytotoxicity (CDC) of wild-type (WT) pAECs by hCTLA4Ig was measured by flow cytometry. RESULTS: Sera containing hCTLA4-Ig demonstrated significantly increased IgG (but not IgM) binding to pAECs (relative geometric mean [rGM]â¯=â¯1.8) compared to sera without hCTLA-4Ig (rGM =1.3) (pâ¯<â¯.01). In contrast, there was no increased binding to pRBCs or CD3+T cells. hCTLA4-Ig did not result in cytotoxicity of WT pAECs. CONCLUSIONS: pAECs might not be an optimal cell to investigate anti-pig IgG binding when hCTLA4-Ig is administered to the recipient, as a false-positive result may result from hCTLA4-Ig binding to the pAECs. CD3+T cells would be preferable targets (compared to pRBCs) because they express both carbohydrate and MHC class I/II antigens.
Assuntos
Abatacepte/uso terapêutico , Anticorpos Heterófilos/sangue , Aorta/patologia , Endotélio Vascular/metabolismo , Transplante de Tecidos , Abatacepte/metabolismo , Animais , Animais Geneticamente Modificados , Citotoxicidade Celular Dependente de Anticorpos , Aorta/transplante , Células Cultivadas , Modelos Animais de Doenças , Endotélio Vascular/patologia , Reações Falso-Positivas , Técnicas de Inativação de Genes , Humanos , Proteína Cofatora de Membrana/genética , Papio , Ligação Proteica , Suínos , Transplante HeterólogoRESUMO
CONTEXT: Immunoassay interference has been most often found with prolactin measurement. However, only few data exist on immunoassay interference for other hormones. CASE DESCRIPTION: A 36-year-old woman with obesity (body mass index, 31 kg/m2) had regularly attended our endocrine unit for type 2 diabetes therapy. When she was included as a control subject in a study for obesity management, detailed laboratory testing was performed, including PTH. In the absence of clinical symptoms, she presented with normal calcium, phosphate, and vitamin D levels. However, the PTH levels were >5000 ng/L. These results were obtained using the Roche Elecsys electrochemiluminescence assay. Repeated measurements with this assay (mouse antibody) led to the same findings. However, using an Euroimmun assay (goat antibody), the exact PTH values were measured at 18.0 ng/L. After pretreatment with a heterophilic antibody blocking reagent, the results of the Roche assay had decreased to a normal level. This phenomenon was explained by the detection of human anti-mouse antibodies in the proband's serum. CONCLUSIONS: In cases of prolactin immunoassay interference, endogenous antibodies will bind to the hormone in vivo, resulting in complexes of a high molecular weight that are less efficiently cleared by the kidneys and, thus, accumulate in the blood. In contrast, the PTH values >5000 ng/L detected in our subject most likely had resulted from the specific interference of the human anti-mouse antibodies present in the proband's serum with the assay antibody, resulting in artificial stimulation of the Roche assay detection system ex vivo.
Assuntos
Anticorpos Heterófilos/sangue , Imunoensaio/métodos , Obesidade/imunologia , Hormônio Paratireóideo/imunologia , Adulto , Animais , Anticorpos Heterófilos/imunologia , Feminino , Humanos , Camundongos/imunologia , Obesidade/sangue , Hormônio Paratireóideo/sangueRESUMO
Monitoring for immune rejection is crucial for long-term survival of pig xenografts. Circulating DNA is a promising non-invasive biomarker for either organ injury or response to therapy. In this study, circulating pig-specific DNA (cpsDNA) was monitored during xenograft rejection. Potential targets of cpsDNA were selected by in silico analysis, and species specificity of selected primers was confirmed by PCR. Subsequently, cpsDNA as a biomarker was evaluated using a complement-dependent cytotoxicity (CDC) assay in vitro. Then, early diagnosis and response to rapamycin were assessed by an in vivo imaging model of pig-to-mouse cell transplantation. Finally, cpsDNA was monitored in a pig-to-monkey artery patch transplantation model. The results showed that (a) a method of cpsDNA quantitation was established for application in mouse and nonhuman primate models; (b) cpsDNA reflected CDC in vitro; (c) cpsDNA in vivo mirrored xenograft rejection, and correlated with xenograft loss in pig-to-mouse cell transplantation; (d) cpsDNA was significantly reduced when rapamycin was administered; and (e) dynamic cpsDNA was detectable in pig-to-monkey artery patch transplantation. In conclusion, measurement of cpsDNA could prove to be a less invasive, but more specific and sensitive low-cost biomarker enabling monitoring of xenograft rejection and the response to immunosuppressive therapy.
Assuntos
DNA/sangue , Rejeição de Enxerto/sangue , Porco Miniatura/genética , Animais , Anticorpos Heterófilos/sangue , Biomarcadores , Células Cultivadas , Primers do DNA , Células Endoteliais/transplante , Feminino , Genes Reporter , Rejeição de Enxerto/tratamento farmacológico , Rejeição de Enxerto/patologia , Xenoenxertos , Humanos , Artéria Ilíaca/citologia , Macaca fascicularis , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Sirolimo/uso terapêutico , Especificidade da Espécie , SuínosRESUMO
We investigated the predictive biomarkers for graft rejection in pig-to-non-human primate (NHP) full-thickness corneal xenotransplantation (n = 34). The graft score (0-12) was calculated based on opacity, edema, and vascularization. Scores ≥ 6 were defined as rejection. NHPs were divided into two groups: (a) graft rejection within 6 months; and (b) graft survival until 6 months. In the evaluation of 2-week biomarkers, none of the NHPs showed rejection within 2 weeks and the 34 NHPs were divided into two groups: (a) entire rejection group (n = 16); and (b) survival group (n = 18). In the evaluation of 4-week biomarkers, four NHPs showing rejection within 4 weeks were excluded and the remaining 30 NHPs were divided into two groups: (a) late rejection group (n = 12); and (b) survival group (n = 18). Analysis of biomarker candidates included T/B-cell subsets, levels of anti-αGal IgG/M, donor-specific IgG/M from blood, and C3a from plasma and aqueous humor (AH). CD8+ IFNγ+ cells at week 2 and AH C3a at week 4 were significantly elevated in the rejection group. Receiver operating characteristic areas under the curve was highest for AH C3a (0.847) followed by CD8+ IFNγ+ cells (both the concentration and percentage: 0.715), indicating excellent or acceptable discrimination ability, which suggests that CD8+ IFNγ+ cells at week 2 and AH C3a at week 4 are reliable biomarkers for predicting rejection in pig-to-NHP corneal xenotransplantation.
Assuntos
Anticorpos Heterófilos/sangue , Biomarcadores/sangue , Complemento C3a/análise , Transplante de Córnea , Rejeição de Enxerto/diagnóstico , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Subpopulações de Linfócitos/imunologia , Animais , Ativação do Complemento , Rejeição de Enxerto/sangue , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/prevenção & controle , Xenoenxertos , Imunossupressores/uso terapêutico , Contagem de Linfócitos , Macaca mulatta , Valor Preditivo dos Testes , Estudos Retrospectivos , Suínos , Imunologia de Transplantes , Transplante HeterólogoRESUMO
BACKGROUND: Heterophilic antibodies are still an important source of interference in immunoassays, but reports of interference with D-dimers are rare. Are D-dimer level abnormalities, found in the clinic, caused by heterophilic antibodies as well, or are other mechanisms involved? We will elaborate on this issue through two different examples in this article. METHODS: Serum from two patients with significantly elevated levels of D-dimers were measured and compared by different methods, diluted, and dealt with heterophilic antibody blockers. At the same time, to retrieve the interference, we focused on the cause of D-dimer false positives and made a systematic review of the literature. RESULTS: The D-dimer values were normal (0.49 and 0.15 µg/mL) detected with different testing method and decreased after addition of heterophilic antibody blocking reagent. According to literature data, there were 66.7% (4/6) references showed the interference were heterophilic antibody. CONCLUSIONS: The influence of heterophilic antibodies on the measurement of D-dimers remains a big challenge. Different measuring instruments and methods may have significant differences in the measurement of D-dimers. By using a combination of instrumental methods for measuring, incorporating heterophilic antibody blockers, and combining with clinical performance and imaging data, most of the interference can be eliminated.