Analytical validation of new ELISAs for the quantitation of polyclonal free light chains and comparison to existing assays for healthy and patient samples.
J Immunol Methods
; 478: 112713, 2020 03.
Article
em En
| MEDLINE
| ID: mdl-31783021
ABSTRACT
BACKGROUND:
Polyclonal FLCs can be used as a biomarker of inflammation and immune activation in a range of diseases. This study evaluated the performance of new FLC ELISAs (Seralite FLC ELISA) for the quantitation of polyclonal κ and λ FLC, including comparisons to existing assays.METHODS:
Technical performance was assessed for the ELISA and reference ranges were generated using healthy donor serum (N = 91). Patients with a range of conditions associated with polyclonal FLC dysregulation (N = 164) were measured across platforms.RESULTS:
The ELISAs generated references ranges of 8.72-23.0 mg/L κ FLC, and 8.52-25.24 mg/L for λ FLC. ELISAs demonstrated linearity across the calibration range and intra-assay (≤ 8.7%) and inter-assay (≤ 12.3%) imprecision was low. The limit of detection was 0.63 mg/L for κ and 0.57 mg/L for λ FLC. Minimal cross-reactivity was observed for interference agents, alternate FLC and whole immunoglobulin (median change ≤3.6 mg/L). Assays showed good batch-to-batch consistency. For patient samples, methods generated different κ and λ FLC concentrations and differences were seen between methods for the number of patients classified as below, with and above references ranges for κ and λ FLC. There was no significant difference in the FLC sum between the different techniques.CONCLUSIONS:
The ELISAs displayed good analytical and technical performance. The quantification of individual κ and λ FLC appears inherently different between platforms. These differences are attenuated if using the FLC sum, which was similar between methods and provided agreement in relation to patients having normal or elevated FLCs.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Kit de Reagentes para Diagnóstico
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Cadeias kappa de Imunoglobulina
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Cadeias lambda de Imunoglobulina
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Doenças do Sistema Imunitário
Tipo de estudo:
Observational_studies
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Risk_factors_studies
Limite:
Humans
Idioma:
En
Revista:
J Immunol Methods
Ano de publicação:
2020
Tipo de documento:
Article