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1.
Amyloid ; : 1-11, 2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38973117

RESUMO

BACKGROUND: Cardiac involvement in systemic light chain amyloidosis (AL) leads to chronic heart failure and is a major prognosis factor. Severe cellular defects are provoked in cardiac cells by tissue-deposited amyloid fibrils of misfolded free immunoglobulin light chains (LCs) and their prefibrillar oligomeric precursors. OBJECTIVE: Understanding the molecular mechanisms behind cardiac cell cytotoxicity is necessary to progress in therapy and to improve patient management. One key question is how extracellularly deposited molecules exert their toxic action inside cardiac cells. Here we searched for direct evidence of amyloid LC uptake by cardiomyocytes in patient biopsies. METHODS: We immunolocalized LCs in cardiac biopsies from four AL cardiac amyloidosis patients and analysed histopathological images by high resolution confocal microscopy and 3D image reconstruction. RESULTS: We show, for the first time directly in patient tissue, the presence of LCs inside cardiomyocytes, and report their proximity to nuclei and to caveolin-3-rich areas. Our observations point to macropinocytosis as a probable mechanism of LC uptake. CONCLUSIONS: Internalisation of LCs occurs in patient cardiomyocytes. This event could have important consequences for the pathogenesis of the cardiac disease by enabling interactions between amyloid molecules and cellular organelles inducing specific signalling pathways, and might bring new insight regarding treatment.

2.
EJHaem ; 5(3): 455-461, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38895087

RESUMO

Multiple myeloma (MM) is a disease, that at times poses diagnostic and monitoring challenges. Over the last decades laboratory methods have been expanded with serum free light chain (FLC) analysis. Alerted by two index cases with clinical impact due to failure of the FLC analysis to indicate a disease progression, we aimed to identify any clinical consequences due to known differences between FLC analysis methods. We applied two FLC analysis methods (Freelite Binding Site [FBS] and N-Latex Siemens [NLS]) on all patients with MM and monoclonal gammopathy of uncertain significance diagnosed/followed up at Södra Älvsborg Hematology Unit, from April to December 2022. From a total of 123 patients with malignant plasma cell disorder, we identified five cases (4.1%) where solely the FBS method, as opposed to NLS, urine and serum electrophoresis, could support diagnosis or detect progression. The consequences of this discrepancy included not only change of diagnosis or delayed therapy but also change of treatment. Our findings indicate that a stronger awareness of the potential weaknesses of different FLC methods is needed, which calls for a closer collaboration between clinical chemists and hematologists.

3.
J Biol Chem ; 300(4): 107174, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38499153

RESUMO

AL amyloidosis is a life-threatening disease caused by deposition of immunoglobulin light chains. While the mechanisms underlying light chains amyloidogenesis in vivo remain unclear, several studies have highlighted the role that tissue environment and structural amyloidogenicity of individual light chains have in the disease pathogenesis. AL natural deposits contain both full-length light chains and fragments encompassing the variable domain (VL) as well as different length segments of the constant region (CL), thus highlighting the relevance that proteolysis may have in the fibrillogenesis pathway. Here, we investigate the role of major truncated species of the disease-associated AL55 light chain that were previously identified in natural deposits. Specifically, we study structure, molecular dynamics, thermal stability, and capacity to form fibrils of a fragment containing both the VL and part of the CL (133-AL55), in comparison with the full-length protein and its variable domain alone, under shear stress and physiological conditions. Whereas the full-length light chain forms exclusively amorphous aggregates, both fragments generate fibrils, although, with different kinetics, aggregate structure, and interplay with the unfragmented protein. More specifically, the VL-CL 133-AL55 fragment entirely converts into amyloid fibrils microscopically and spectroscopically similar to their ex vivo counterpart and increases the amorphous aggregation of full-length AL55. Overall, our data support the idea that light chain structure and proteolysis are both relevant for amyloidogenesis in vivo and provide a novel biocompatible model of light chain fibrillogenesis suitable for future mechanistic studies.


Assuntos
Amiloide , Cadeias Leves de Imunoglobulina , Amiloide/metabolismo , Amiloide/química , Humanos , Cadeias Leves de Imunoglobulina/metabolismo , Cadeias Leves de Imunoglobulina/química , Cadeias Leves de Imunoglobulina/genética , Simulação de Dinâmica Molecular , Regiões Constantes de Imunoglobulina/metabolismo , Regiões Constantes de Imunoglobulina/genética , Regiões Constantes de Imunoglobulina/química , Amiloidose de Cadeia Leve de Imunoglobulina/metabolismo , Amiloidose de Cadeia Leve de Imunoglobulina/patologia , Cinética , Domínios Proteicos
4.
Arq. neuropsiquiatr ; 82(3): s00441779690, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1557128

RESUMO

Abstract Background Oligoclonal bands (OCBs) and Kappa free light chains (FLCs) in the cerebrospinal fluid (CSF) are sensitive markers of intrathecal immunoglobulin (Ig)G synthesis in patients with multiple sclerosis. Objective To evaluate the concordance rate between OCBCs and the Kappa index (KI) in patients with suspected multiple sclerosis (MS). Methods Patients with suspected MS were referred to a specialized CSF laboratory as part of their diagnostic investigation. Paired CSF and serum samples were collected and submitted to detection of OCBs and determination of the KI. Positive and negative results were determined with both methods, and the percentage of agreement between them was established. Results In total, 171 serum and CSF samples from 171 patients were included in the analysis. The mean age of the patients was of 40 ± 14.2 years; 18.9% of them were male, and 81.1% were female. The OCBs and KI presented concordant results in 161 (94.2%) samples: in 74 (43.3%), both were positive, and in 87 (50.9%), both were negative. In 10 cases, the results were discrepant: KI positive/OCB negative in 8 and OCB positive/KI negative in 2 cases. Conclusion The KI and OCBs presented high concordance level. Currently, the detection of OCBs in the CSF is the standard method for MS diagnosis, but it is time-consuming, and its visual interpretation can be difficult. The results suggest that the KI is a good alternative for the detection of intrathecal immunoproduction in cases of suspected MS.


Resumo Antecedentes Bandas oligoclonais (BOCs) e cadeias leves de imunoglobulina (free light chains, FLCs, em inglês) Kappa no líquido cefalorraquidiano (LCR) são marcadores sensíveis da síntese intratecal de imunoglobulina (Ig)G em pacientes com esclerose múltipla (EM). Objetivo Avaliar a taxa de concordância entre BOCs e o índice Kappa (IK) em pacientes com suspeita de EM. Métodos Pacientes com suspeita de EM foram encaminhados a um laboratório especializado em LCR como parte de sua investigação diagnóstica. Amostras pareadas de LCR e soro foram coletadas e investigadas quanto à presença de BOCs e submetidas à determinação do IK. Resultados positivos e negativos foram determinados com ambos os métodos, e estabeleceu-se o percentual de concordância entre eles. Resultados Ao todo, 171 amostras de soro e LCR de 171 pacientes foram incluídas na análise. A média de idade dos pacientes foi de 40 ± 14,2 anos; 18,9% deles eram do sexo masculino, e 81,1%, do sexo feminino. Resultados concordantes entre as BOCs e o IK foram observados em 161 (94,2%) amostras: em 74 (43,3%), ambos foram positivos, e em 87 (50,9%), ambos foram negativos. Em 10 casos, os resultados foram discrepantes: IK positivo/BOC negativo em 8, e BOC positivo/IK negativo em 2. Conclusão Observou-se alto nível de concordância entre o IK e as BOCs. A detecção de BOCs no LCR é atualmente o método padrão para o diagnóstico de EM, mas é demorado, e sua interpretação visual pode ser difícil. Os resultados sugerem que o IK pode ser uma alternativa para a detecção de imunoprodução intratecal em casos de suspeita de EM.

5.
Eur Cardiol ; 18: e40, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37456770

RESUMO

Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) is responsible for the regulation of genes involved in inflammation and immune responses. NF-κB may play an important role in cardiovascular diseases (CVDs), atherosclerosis and diabetes. Several therapeutic agents used for the treatment of CVDs and diabetes, such as pimobendan and sodium-glucose cotransporter 2 inhibitors, exert anti-inflammatory effects by inhibiting NF-κB activation; anti-inflammatory therapy may have beneficial effects in CVDs and diabetes. Several pharmacological agents and natural compounds may inhibit NF-κB, and these agents alone or in combination may be used to treat various inflammatory diseases. Immunoglobulin-free light chains could be surrogate biomarkers of NF-κB activation and may be useful for evaluating the efficacy of these agents. This review discusses recent advances in our understanding of how the NF-κB signalling pathway controls inflammation, metabolism and immunity, and how improved knowledge of these pathways may lead to better diagnostics and therapeutics for various human diseases.

6.
Clin Chem Lab Med ; 61(7): 1288-1299, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37015073

RESUMO

OBJECTIVES: Free light chain (FLC) is used for the diagnosis and prediction with regard to the progression risk of plasma cell disorders and Freelite reagent using the SPAplus analyzer (The Binding Site) has been one of the widely used option. However, N Latex FLC reagent with the Atellica CH 930 analyzer (Siemens Healthineers) has shown the advantages of automation and high throughput. We aimed to evaluated clinical implication by differential analytical performances of two assays. METHODS: A total of 322 serum samples were collected from 193 patients requested for FLC analysis including 131 multiple myeloma patients. The precision, linearity, dilution recovery of N Latex FLC assay was evaluated. We compared the two assays and analyzed the monomer-dimer pattern for discrepant results. RESULTS: The precision, linearity, and dilution recovery performance was appropriate for the routine use in clinical laboratories. Despite the good correlation within normal range, proportional bias up-to 170% was observed in samples with high concentrations especially for lambda. The higher value samples with N Latex FLC assay contained more monomer forms than controls. All opposite changes of FLC burden by the N Latex FLC assay proved to present concordant dynamic changes when assessed by serum protein electrophoresis. CONCLUSIONS: Clinical laboratories should be aware of the inter-assay variability of FLC quantitative measurements using different platforms, especially for high concentrations of both kappa and lambda measurements, possibly due to monomer/dimer ratio diversity. Clinical interpretations for multiple myeloma disease status might not be dramatically affected only when the same assay is utilized during follow-up periods.


Assuntos
Mieloma Múltiplo , Paraproteinemias , Humanos , Cadeias kappa de Imunoglobulina , Cadeias lambda de Imunoglobulina , Mieloma Múltiplo/diagnóstico , Látex , Cadeias Leves de Imunoglobulina , Paraproteinemias/diagnóstico
7.
Ann Hematol ; 102(6): 1459-1466, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37060464

RESUMO

We aimed to describe the clinical and biological characteristics and the prognosis of patients presenting with an additional light chain (LC) band along with a complete monoclonal protein on immunofixation (IF).An 8-year descriptive study was conducted to assess all cases with confirmed monoclonal gammopathies (MG). We studied those with an entire M-protein with 2 bands of LC of the same isotype based on the results of IF. Data were collected from patients' files.Among 548 cases of MG, we found 32 cases (5.8%) with an additional LC band. We included 28 patients (5%) with a confirmed diagnosis of multiple myeloma (MM). The m/f ratio was 2.5 with a median age of 63 years [32-80 years]. All MM patients had anemia, 16 (57%) had renal failure, 14 (50%) had lytic lesions, 9 (32%) received hemodialysis, and 7 (25%) had hypercalcemia. The free-kappa-lambda ratio was abnormal in all cases: median = 0.07 [0.002-58.57]. The mean overall survival (OS) was 22 months ± 38.76.Fifteen MM patients (48%) received chemotherapy, and 7 (22%) autologous stem cell transplants (SCT). Patients who received SCT had an OS higher than those who received other treatments (p = 0.038). OS was low in patients with high ß2microglobulin levels (rho = -0.791; p = 0.001), and abnormally low free-kappa-lambda ratio (rho = -0.852;p = 0.04).The presence of an additional LC band with a complete monoclonal protein seems to identify newly diagnosed MM patients with poor outcomes and frequent renal impairment.


Assuntos
Mieloma Múltiplo , Paraproteinemias , Humanos , Pessoa de Meia-Idade , Mieloma Múltiplo/terapia , Mieloma Múltiplo/tratamento farmacológico , Cadeias Leves de Imunoglobulina , Paraproteinemias/diagnóstico , Prognóstico , Transplante de Células-Tronco , Cadeias lambda de Imunoglobulina , Cadeias kappa de Imunoglobulina
8.
Heliyon ; 9(4): e15190, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37095940

RESUMO

Amyloid formation by cells is a stepwise process that occurs in macrophages and cells capable of transforming into a macrophage phenotype. One such cell is the mesangial cell in the kidney. It has been shown that mesangial cells are engaged in AL (light chain associated)- amyloidogenesis after transforming phenotypically from a smooth muscle to a macrophage phenotype. The actual process of amyloid fibril formation has not been dissected. This ultrastructural study which includes the examination of lysosomal gradient specimens addresses this issue by analyzing the sequence of events that takes place as fibrils are formed in endosomes and lysosomes. The findings indicate that fibrillogenesis begins in endosomes but is completed and most pronounced in the lysosomal compartment. As early as 10 min after incubation of human mesangial cells with AL-LCs, amyloid fibrils are formed in endosomes but mostly occurs in the mature lysosomal compartment. This is the first time that fibril formation is demonstrated experimentally occurring inside human mesangial cells and the entire sequence of events taking place is elucidated.

10.
Kidney Int Rep ; 7(11): 2462-2473, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36531879

RESUMO

Introduction: IgA nephropathy (IgAN) differs from other glomerular diseases by the frequently predominant lambda over kappa light chain deposition. Using the Cure Glomerulonephropathy (CureGN) IgAN cohort, we aimed to determine whether predominant lambda chain deposition is associated with worse clinical outcomes or histopathologic markers of more active disease. Methods: Patients were categorized based on the intensity of light chain staining. The lambda dominant (LD) group was defined by a difference in intensity score of lambda minus kappa ≥ 1+ and the kappa-lambda codominant (KL) group by a difference < 1+. We compared the clinical course of patients in each category from the time of kidney biopsy and time of enrollment into CureGN to the time of remission (proteinuria < 0.3 g/g), 50% reduction in estimated glomerular filtration rate (eGFR), or progression to end-stage kidney disease (ESKD). We also analyzed differences in histopathologic characteristics between the 2 groups. Results: Among 440 patients, we found no significant differences between groups in baseline clinical characteristics nor in rates of remission, 50% reduction in eGFR, or progression to ESKD. Patients in the LD group had a modestly greater frequency of IgG staining ≥ 1+. The biopsy results of 234 patients reviewed by CureGN pathologists revealed a greater frequency of endocapillary hypercellularity (51.1% vs. 36.3%, P = 0.04) in the LD group, but no other significant difference in histopathologic features. Conclusion: In IgAN, we found an association between lambda predominance and increased endocapillary hypercellularity, but no association with clinical outcomes.

11.
Glob Heart ; 17(1): 80, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36382160

RESUMO

Inflammation plays an important role in the development and progression of cardiovascular diseases (CVDs). Hypertension and hyperlipidemia are the key risk factors of CVDs and induce inflammation in the heart and vessels. Unhealthy diet, infection, and smoking coupled with genetic factors lead to the development of CVDs as well as induce inflammation. Risk factors of CVDs such as hypertension and hyperlipidemia along with diabetes activate nuclear factor kappa B, which regulates the transcription of immunoglobulin free light chain (FLC) κ in B cells and the production of multiple inflammatory molecules, leading to inflammation. FLCs are novel biomarkers of inflammation, and their levels have been associated with overall mortality in a general population and with cardiovascular outcomes. In this review, the role of inflammation in the pathogenesis of CVDs, new biomarkers of inflammation, and dietary options counterbalancing inflammatory processes, such as the polyphenol-rich French maritime pine bark extract Pycnogenol, are discussed.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus , Hipertensão , Humanos , Doenças Cardiovasculares/prevenção & controle , Inflamação , Biomarcadores
13.
Curr Cardiol Rep ; 24(7): 839-850, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35524881

RESUMO

PURPOSE OF REVIEW: This review will explore the role of cardiac imaging in guiding treatment in the two most commonly encountered subtypes of cardiac amyloidosis (immunoglobulin light-chain amyloidosis [AL] and transthyretin amyloidosis [ATTR]). RECENT FINDINGS: Advances in multi-parametric cardiac imaging involving a combination of bone scintigraphy, echocardiography and cardiac magnetic resonance imaging have resulted in earlier diagnosis and initiation of treatment, while the evolution of techniques such as longitudinal strain and extracellular volume quantification allow clinicians to track individuals' response to treatment. Imaging developments have led to a deeper understanding of the disease process and treatment mechanisms, which in combination result in improved patient outcomes. The rapidly expanding treatment regimens for cardiac amyloidosis have led to an even greater reliance on cardiac imaging to help establish an accurate diagnosis, monitor treatment response and aid the adjustment of treatment strategies accordingly.


Assuntos
Neuropatias Amiloides Familiares , Cardiomiopatias , Amiloidose de Cadeia Leve de Imunoglobulina , Neuropatias Amiloides Familiares/patologia , Técnicas de Imagem Cardíaca , Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/terapia , Ecocardiografia , Humanos , Amiloidose de Cadeia Leve de Imunoglobulina/diagnóstico por imagem , Amiloidose de Cadeia Leve de Imunoglobulina/patologia
14.
Dev Comp Immunol ; 131: 104392, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35271860

RESUMO

In pigs (Sus scrofa), the initial immunoglobulin rearrangement of the κ light chain is replaced by λ before the heavy chains rearrange, and the light chains may rearrange even later. This study investigates whether these developmental differences are reflected in the usage of IGK and IGL genes. We found large differences between peripheral B cells and those developing in the bone marrow, and between B cells in germ-free piglets and conventional pigs. During early B cell development in the bone marrow, more 3' V and 5' J gene segments for both light chains are used. However, in the peripheral naive repertoire, more 5' IGLV and 3' IGLJ genes are used. A similar shift toward the use of more 5' IGKV and 3' IGKJ genes is observed later after antigen exposure in conventional pigs. The expression profile showed that most λ+ B cells are generated earlier, while κ+ B cells develop from late precursors that already contain the λ rearrangement. The initial λ rearrangement is retained in both λ+ and κ+ B lymphocytes, and multiple λ transcripts can be found in individual cells. The overall pool of the IGLV repertoire is therefore much larger and more diversified than for IGKV. The κ repertoire is further restricted to the preferential use of only two major IGKV genes, reflecting the limitation for only two consecutive rearrangements. Tracing of silenced λ transcripts in κ+ B cells further confirmed the unconventional mechanism of differential rearrangements in pigs. Our results underline the diversity of the immune system among mammals.


Assuntos
Cadeias Leves de Imunoglobulina , Cadeias kappa de Imunoglobulina , Animais , Linfócitos B , Genes de Imunoglobulinas , Cadeias Leves de Imunoglobulina/genética , Cadeias kappa de Imunoglobulina/genética , Cadeias lambda de Imunoglobulina/genética , Tecido Linfoide , Mamíferos/genética , Suínos
15.
Circ Heart Fail ; 15(6): e009038, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35331001

RESUMO

Immunoglobulin light chain amyloidosis is a rare, multisystemic, phenotypically heterogenous disease affecting cardiovascular, renal, neurological, and gastrointestinal systems to varying degrees. Its underlying cause is a plasma cell dyscrasia characterized by misfolding of monoclonal immunoglobulin light chains which leads to aggregation and deposition of insoluble amyloid fibrils in target organs. Prognosis is primarily dependent on extent of cardiac involvement and depth of hematologic response to treatment. To facilitate development of new therapies, a public-private partnership was formed between the nonprofit Amyloidosis Research Consortium and the US Food and Drug Administration Center for Drug Evaluation and Research. In 2020, the Amyloidosis Forum launched an initiative to identify novel/composite end points and analytic strategies to expedite clinical trials for development of new therapies for the primary hematologic disorder and organ system manifestations. Specialized working groups identified organ-specific end points; additional working groups reviewed health-related quality of life measures and statistical approaches to data analysis. Each working group comprised amyloidosis experts, patient representatives, statisticians, and representatives from the Food and Drug Administration, the UK Medicines and Healthcare Products Regulatory Agency, and pharmaceutical companies. This review summarizes the proceedings and recommendations of the Cardiac Working Group. Using a modified Delphi method, the group identified, reviewed, and prioritized cardiac end points relevant to immunoglobulin light chain amyloidosis in the context of an antiplasma cell therapy. Prioritized cardiovascular end points included overall survival, hospitalization, N-terminal pro-B-type natriuretic peptide level, 6-minute walk test, Kansas City Cardiac Questionnaire, and cardiac deterioration progression-free survival. These recommended components will be further explored through evaluation of clinical trial datasets and formal guidance from regulatory authorities.


Assuntos
Amiloidose , Insuficiência Cardíaca , Amiloidose de Cadeia Leve de Imunoglobulina , Amiloidose/terapia , Humanos , Cadeias Leves de Imunoglobulina , Amiloidose de Cadeia Leve de Imunoglobulina/diagnóstico , Amiloidose de Cadeia Leve de Imunoglobulina/terapia , Qualidade de Vida , Estados Unidos
16.
Eur J Haematol ; 108(6): 493-502, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35184331

RESUMO

OBJECTIVES: Myeloma is characterised by the presence of monoclonal immunoglobulin (M-protein) and the free light chain (FLC) in blood. We investigated whether these M-proteins and FLC are detectable in myeloma patients' saliva to evaluate its utility for non-invasive screening and monitoring of haematological malignancies. METHODS: A total of 57 patients with monoclonal gammopathy and 26 age-matched healthy participants provided paired serum and saliva samples for immunoglobulin characterisation and quantification. RESULTS: Myeloma patients had IgG or IgA M-protein levels ranging up to five times and FLC levels up to a thousand times normal levels of polyclonal immunoglobulins. Despite these highly elevated levels, only two IgG and no IgA M-proteins or FLC could be detected in paired saliva samples. Most patients had reduced levels of serum polyclonal immunoglobulins, but all had normal levels of salivary IgA. CONCLUSIONS: Immunoglobulin transfer from blood is not determined by levels in the systemic circulation and more likely dictated by periodontal inflammation and the integrity of the oral epithelium. Immunoglobulins secreted by bone marrow plasma cells do not substantially enter saliva, which represents a poor medium for myeloma diagnosis. These findings, along with normal salivary IgA levels despite systemic immunoparesis, support a strong partitioning of oral from systemic humoral immunity.


Assuntos
Mieloma Múltiplo , Proteínas do Mieloma , Humanos , Imunoglobulina A , Imunoglobulina G , Cadeias Leves de Imunoglobulina , Imunoglobulinas , Saliva/metabolismo
17.
Early Interv Psychiatry ; 16(3): 272-280, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-33966347

RESUMO

BACKGROUND: Early diagnosis of individuals' at-risk mental state (ARMS) is important for preventing their pathogenesis or, at least, delaying onset of overt psychosis. Traditional diagnosis of ARMS subjects is mainly based on structured interviews, but future diagnosis would be carried out together with biomarkers. AIM: In this study, we report urinary biopyrrins and free immunoglobin light chains κ and λ (κFLC and λFLC) as novel diagnostic biomarker candidates for screening ARMS subjects. METHODS: Nineteen ARMS subjects and 21 age- and sex-matched healthy controls were enrolled in this study. Inclusion criteria of the ARMS subjects were based on a comprehensive assessment of Structured Interview for Prodromal Syndromes. We compared oxidative stress and immunological markers in the urine of ARMS subjects with those of healthy controls by ELISA protocol. RESULTS: Augmentation of biopyrrins and reduction of κFLC and λFLC were found in the ARMS samples, and their diagnostic performance was evaluated by receiver operating characteristic analysis, of which area under the curve was as large as 0.915 in combination. CONCLUSION: Our findings suggest that the ARMS subjects were under higher oxidative stress but lower in B cell activation, and that the combined assay of urinary biopyrrins and free immunoglobulin light chains would be useful for the early detection and screening of ARMS subjects among adolescents.


Assuntos
Cadeias Leves de Imunoglobulina , Estresse Oxidativo , Adolescente , Biomarcadores , Humanos
18.
FEBS J ; 289(2): 494-506, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34482629

RESUMO

Light-chain (AL) amyloidosis is characterized by deposition of immunoglobulin light chains (LC) as fibrils in target organs. Alongside the full-length protein, abundant LC fragments are always present in AL deposits. Herein, by combining gel-based and mass spectrometry analyses, we identified and compared the fragmentation sites of amyloid LCs from multiple organs of an AL λ amyloidosis patient (AL-55). The positions pinpointed here in kidney and subcutaneous fat, alongside those previously detected in heart of the same patient, were aligned and mapped on the LC's dimeric and fibrillar states. All tissues contain fragmented LCs along with the full-length protein; the fragment pattern is coincident across organs, although microheterogeneity exists. Multiple cleavage positions were detected; some are shared, whereas some are organ-specific, likely due to a complex of proteases. Cleavage sites are concentrated in 'proteolysis-prone' regions, common to all tissues. Several proteolytic sites are not accessible on native dimers, while they are compatible with fibrils. Overall, data suggest that the heterogeneous ensemble of LC fragments originates in tissues and is consistent with digestion of preformed fibrils, or with the hypothesis that initial proteolytic cleavage of the constant domain triggers the amyloidogenic potential of LCs, followed by subsequent proteolytic degradation. This work provides a unique set of molecular data on proteolysis from ex vivo amyloid, which allows discussing hypotheses on role and timing of proteolytic events occurring along amyloid formation and accumulation in AL patients.


Assuntos
Neuropatias Amiloides/genética , Amiloide/genética , Proteínas Amiloidogênicas/genética , Amiloidose/genética , Cadeias Leves de Imunoglobulina/genética , Amiloide/metabolismo , Neuropatias Amiloides/metabolismo , Neuropatias Amiloides/patologia , Amiloidose/metabolismo , Amiloidose/patologia , Endopeptidases/genética , Humanos , Cadeias Leves de Imunoglobulina/metabolismo , Cinética , Peptídeo Hidrolases/genética , Agregação Patológica de Proteínas/genética , Agregação Patológica de Proteínas/metabolismo , Agregação Patológica de Proteínas/patologia , Proteólise , Termodinâmica
19.
Front Immunol ; 13: 1089295, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36643913

RESUMO

Objectives: Human gut microbiome has gained great attention for its proposed roles in the development of hypertension. The fungal microbiome in the human gut (i.e. the mycobiome) is beginning to gain recognition as a fundamental part of our microbiome. However, the existing knowledge of human mycobiome has never revealed the association between gut mycobiome and hypertension. It is known that inflammation and immunity contribute to human hypertension. Here, we sought to investigate whether gut mycobiome could predict the development of hypertension and its association with immunoglobulin light chains. Methods and materials: Participants were classified into three cohorts: prehypertension (pre-HTN), hypertension (HTN), and normal-tension (NT) based on their blood pressure. Fresh samples were collected, and the ITS transcribed spacer ribosomal RNA gene sequence was performed. An immunoturbidimetric test was used to examine the serum levels of immunological light chains. Results: Subjects in both of the states of pre-HTN and HTN had different fungal microbiome community compared to the NT group (FDR<0.05). Slightly higher levels of fungal richness and diversity were observed in the groups of pre-HTN and HTN. The relative abundance of Malassezia increased in the HTN group compared to that in the NT group, and the relative abundance of Mortierella enriched in the NT group. For the pre-HTN group, the relative abundance of Malassezia was positively associated with serum the concentration of light chain (LC) κ (r=0.510, P=0.044); for the HTN group, the relative abundance of Mortierella was positively associated with the serum concentration of LC κ (P<0.05), the relative abundance of Malassezia was positively associated with both the serum concentrations of LC κ and LC λ (r>0.30, P<0.05). Conclusions: Our present study demonstrated that gut fungal dysbiosis occurred in the state of prehypertension, and fungal dysbiosis can predict the dysregulation of serum light chains in hypertension patients. Further study on modulating gut fungal community should be focused on balancing the immunological features in hypertension.


Assuntos
Hipertensão , Micobioma , Pré-Hipertensão , Humanos , Cadeias Leves de Imunoglobulina , Pré-Hipertensão/complicações , Disbiose/microbiologia , Hipertensão/complicações
20.
Arq. bras. cardiol ; 118(2): 422-432, 2022. tab, graf
Artigo em Inglês, Português | LILACS | ID: biblio-1364337

RESUMO

Resumo Fundamento Amiloidose sistêmica é uma doença com manifestações clínicas diversas. O diagnóstico envolve suspeita clínica, aliada a métodos complementares. Objetivo Descrever o perfil clínico, laboratorial, eletrocardiográfico e de imagem no acometimento cardíaco da amiloidose sistêmica. Métodos Estudo de uma amostra de conveniência, analisando dados clínicos, laboratoriais, eletrocardiográficos, ecocardiográficos, medicina nuclear e ressonância magnética. Considerou-se significância estatística quando p < 0,05. Resultados Avaliaram-se 105 pacientes (com mediana de idade de 66 anos), sendo 62 homens, dos quais 83 indivíduos apresentavam amiloidose por transtirretina (ATTR) e 22 amiloidose por cadeia leve (AL). Na ATTR, 68,7% eram de caráter hereditário (ATTRh) e 31,3% do tipo selvagem (ATTRw). As mutações mais prevalentes foram Val142Ile (45,6%) e Val50Met (40,3%). O tempo de início dos sintomas ao diagnóstico foi 0,54 e 2,15 anos nas formas AL e ATTR (p < 0,001), respectivamente. O acometimento cardíaco foi observado em 77,9% dos ATTR e 90,9% dos AL. Observaram-se alterações de condução atrioventricular em 20% e intraventricular em 27,6% dos pacientes, sendo 33,7 % na ATTR e 4,5% das AL (p = 0,006). A forma ATTRw apresentou mais arritmias atriais que os ATTRh (61,5% x 22,8%; p = 0,001). Ao ecocardiograma a mediana da espessura do septo na ATTRw x ATTRh x AL foi de 15 mm x 12 mm x 11 mm (p = 0,193). Observou-se BNP elevado em 89,5% dos indivíduos (mediana 249 ng/mL, IQR 597,7) e elevação da troponina em 43,2%. Conclusão Foi possível caracterizar, em nosso meio, o acometimento cardíaco na amiloidose sistêmica, em seus diferentes subtipos, através da história clínica e dos métodos diagnósticos descritos.


Abstract Background Systemic amyloidosis is a disease with heterogeneous clinical manifestations. Diagnosis depends on clinical suspicion combined with specific complementary methods. Objective To describe the clinical, laboratory, electrocardiographic, and imaging profile in patients with systemic amyloidosis with cardiac involvement. Methods This study was conducted with a convenience sample, analyzing clinical, laboratory, electrocardiographic, echocardiographic, nuclear medicine, and magnetic resonance data. Statistical significance was set at p < 0.05. Results A total of 105 patients were evaluated (median age of 66 years), 62 of whom were male. Of all patients, 83 had transthyretin (ATTR) amyloidosis, and 22 had light chain (AL) amyloidosis. With respect to ATTR cases, 68.7% were the hereditary form (ATTRh), and 31.3% were wild type (ATTRw). The most prevalent mutations were Val142Ile (45.6%) and Val50Met (40.3%). Time from onset of symptoms to diagnosis was 0.54 and 2.15 years, in the AL and ATTR forms, respectively (p < 0.001). Cardiac involvement was observed in 77.9% of patients with ATTR and in 90.9% of those with AL. Alterations were observed in atrioventricular and intraventricular conduction in 20% and 27.6% of patients, respectively, with 33.7% in ATTR and 4.5% in AL (p = 0.006). In the ATTRw form, there were more atrial arrhythmias than in ATTRh (61.5% versus 22.8%; p = 0.001). On echocardiogram, median septum thickness in ATTRw, ATTRh, and AL was 15 mm, 12 mm, and 11 mm, respectively (p = 0.193). Elevated BNP was observed in 89.5% of patients (median 249, ICR 597.7), and elevated troponin was observed in 43.2%. Conclusion In this setting, it was possible to characterize cardiac involvement in systemic amyloidosis in its different subtypes by means of clinical history and the diagnostic methods described.


Assuntos
Humanos , Masculino , Feminino , Adulto , Cardiologia , Neuropatias Amiloides Familiares/diagnóstico por imagem , Amiloidose/diagnóstico por imagem , Cardiomiopatias/diagnóstico por imagem , Encaminhamento e Consulta , Brasil , Pré-Albumina/genética , Ecocardiografia
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