RESUMO
Determination of the C1q content of cerebrospinal fluid (CSF) may be of value in understanding the immunological reactions occurring within the central nervous system (CNS). A double sandwich ELISA method has been developed for the detection of C1q in human serum and CSF. It uses polyclonal antibodies and is sensitive in the nanogram range. The mean concentrations of C1q were determined to be 127 micrograms/ml in serum and 0.4 microgram/ml in CSF. These results suggest that increased levels of C1q in the CSF play a role in some neurodegenerative disorders.
Assuntos
Enzimas Ativadoras do Complemento/líquido cefalorraquidiano , Complemento C1/líquido cefalorraquidiano , Ensaio de Imunoadsorção Enzimática , Adolescente , Adulto , Idoso , Doença de Alzheimer/sangue , Doença de Alzheimer/líquido cefalorraquidiano , Esclerose Lateral Amiotrófica/sangue , Esclerose Lateral Amiotrófica/líquido cefalorraquidiano , Enzimas Ativadoras do Complemento/análise , Enzimas Ativadoras do Complemento/normas , Complemento C1/análise , Complemento C1/normas , Complemento C1q , Ensaio de Imunoadsorção Enzimática/normas , Humanos , Imunodifusão , Pessoa de Meia-Idade , Padrões de ReferênciaRESUMO
Non-competitive 2-site radioimmunoassays (RIA) for the determination of the complement proteins C1q, C4 and C3 in cerebrospinal fluid (CSF) are described. The quantitative results of the RIAs were the same as those obtained by other assay methods: radial immunodiffusion and turbidimetry and, in the case of C4, the haemolytic assay. The concentrations of the complement proteins in paired CSF and serum samples from a group of 60 patients were measured, as well as those of albumin and IgG. The ratios (concentration in CSF)/(concentration in serum) of the complement proteins correlated poorly with that of albumin. In contrast, the ratio of IgG was significantly correlated with that of albumin. The ratios of the complement proteins were higher than might be expected on the basis of their molecular masses. This suggests that these proteins may be synthesized within the normal central nervous system.
Assuntos
Enzimas Ativadoras do Complemento/líquido cefalorraquidiano , Complemento C3/líquido cefalorraquidiano , Complemento C4/líquido cefalorraquidiano , Adolescente , Adulto , Idoso , Enzimas Ativadoras do Complemento/sangue , Enzimas Ativadoras do Complemento/normas , Complemento C1q , Complemento C3/normas , Complemento C4/normas , Estabilidade de Medicamentos , Feminino , Humanos , Imunodifusão , Masculino , Pessoa de Meia-Idade , Radioimunoensaio/normas , Padrões de Referência , Valores de ReferênciaRESUMO
A new method for the determination of C1q in serum and cerebral spinal fluid (CSF) is described. The method has a sensitivity of 6 ng per assay or 1.2 mg/l. With this technique the mean value for C1q in normal human serum was 276 +/- 25 mg/l. The ratio of C1q in the blood compared with that in the CSF of normal individuals was more than 400: 1, since essentially no C1q could be detected in normal CSF. This ratio dropped considerably in some patients with neurological disorders, due to an increase in C1q levels in the CSF. Evidence is presented that these increased levels of CSF C1q are largely due to local synthesis of C1q rather than transudation of plasma C1q. This suggests that C1q in the CSF may serve as a marker of macrophage activity inside the central nervous system.