Ceruloplasmin levels in human sera from various diseases and their correlation with patient’s age and gender

Abstract

Ceruloplasmin (Cp), a copper metalloprotein in human serum has been a valuable diagnostic marker in Wilson's disease where Cp levels tend to be low while high levels in serum were associated with myocardial infarction, neoplastic and inflammatory conditions. There is no standardized reference method for Cp and current immunologic and bichromatic assays have a number of drawbacks. The method described here uses immunoaffinity chromatography to remove six of the most abundant proteins from a serum sample and high-pressure liquid chromatography (HPLC) with a size-exclusion column to separate Cp from other serum proteins and any free Cu prior to analysis of 63 Cu and 65 Cu by inductively-coupled plasma mass spectrometry (ICPMS). Identification of Cp is based on retention time match of the unknown protein in the serum sample with the Cp external standard and the presence of 63 Cu and 65 Cu at a ratio of 2.2 ± 0.1. The method accuracy, as established independently by two of the authors with a reference serum certified for Cp, is 98 to 101% and the coefficient of variation is 6.4% and 5.4%, respectively. The assay was used to analyze a total of 167 human sera for Cp from patients with myocardial infarction (MI), pulmonary embolism (PE), rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), other forms of arthritis, and a set of healthy patients as normal controls (NC). Our data show that Cp concentrations tend to be higher in MI, RA, and SLE patients, higher in female as compared to male patients, and we did not observe a correlation between Cp concentration and patient's age for the set of 70 patients for which we had gender and age information.

Peroxidase Activity of Human Hemoproteins: Keeping the Fire under Control

“…Trapping of Fe 3+ by transferrin prevents iron participation in redox chemistry [ 114 ]. CP is an abundant acute phase protein whose concentration can reach the value of 4–10 µM with pathologies [ 115 , 116 ].…”

LA-ICP-MS with microarray chip sampling to determine holoceruloplasmin in serum

“…Many articles have described analytical methods to determine Cu in serum, including graphite furnace atomic absorption spectrometry (GFAAS) and ICP-MS. 18,19 However, the determined Cu concentration in serum or organ tissues cannot be directly correlated to holo-CP because copper can also bind to various proteins other than CP, such as transcuprein, albumin, and amino acids or can exist in an unbound form, i.e., free copper, that is toxic. 20 Recently, LA-ICP-MS has been used to determine Cu distributions in biological tissue or in gel separated by electrophoresis.…”