A curve was generated by use of linear 1/x regression with the known concentration of each standard (x) to its measured area ratio (y), giving a 7-point calibration curve with linear 1/x regression for quantification for IgG subclasses 1, 2, and 3 and a 6-point calibration curve with linear 1/x regression for quantification of IgG subclass 4 and total IgG.
Imprecision statistics (see online Supplemental Table 4) demonstrated intra- and interassay imprecision data for subclasses 1, 2, 3 and total IgG of <10%.
1 shows the results for the linear regression analysis of subclasses 1-4 and total IgG, with the concentration found by LC-MS/MS on the y axis and the concentration found by nephelometry on the x axis.
Immunoglobulin subclasses are differentially regulated in response to different antigenic stimuli (4), (5).
Since human IgG subclasses are highly homologous with almost 95% aminoacid sequence identity (15), some human IgG subclass restricted mouse MAbs may recognize epitopes shared by multiple IgG subclasses.
The aim of the present study is production and characterization of MAbs with specificity for multiple IgG subclasses.
IgG, IgM and IgE levels were assayed using the same methodology, IgG subclasses (1 to 4) were measured by nephelometry.
Some studies have identified lower mean concentrations of IgG subclasses in IgA deficient patients with an increased susceptibility to infections, although this finding has not led to a clear association in all cases.
The test offers information on cholesterol subclasses
that allows a true determination of people at risk for cardiovascular disease.
A multiple issuance series also consists of class A, B and C notes, with subclasses
that may be offered independently and have differing terms, issuance dates and maturities.