Anti-Cardiolipin, Anti-Cardiolipin Plus Bovine, or Human β2Glycoprotein-I and Anti-Human β2Glycoprotein-I Antibodies in a Healthy Infant Population

Background enic antiphospholipid antibodies studies are usually conducted on populations of adults. Studies involving normal children are scant. s dy reactivity against CL alone (true aCL), CL-complexed to bovine β2GP-I (aCL-bovine β2GP-I), or human (aCL-human β2GP-I) β2GP-I, or to phospholipid-free human β2GP-I (anti-human β2GP-I) was determined by ELISA in serum samples from 360 Mexican children ranging from 1 month through 8 years of age. s tical analysis of variance and rankings of Kruskal-Wallis demonstrated no significant difference in all tested antibody activities between ages and genders of the study population. Values are presented as a percentile distribution included between 5 and 99, corresponding to the percentages of the studied population. Normal arbitrary units (AU) for IgG, IgA, and IgM true aCL that correspond to the 95 and 99 percentiles are as follows: 2.15 and 3.5; 2.35 and 5.0, and 3.15 and 4.5, respectively. IgG, IgA, and IgM aCL-bovine β2GP-I activities are 2.6 and 5.0, 3.0 and 5.0, and 2.7 and 6.0 AU, respectively, while IgG activities of aCL-bovine and human β2GP-I are 1.45 and 1.80, respectively. Normal values for IgG anti-human β2GP-I are 1.85 AU. sions elevated serum levels of antibodies to CL and/or β2GP-I have been associated with thrombotic and hematologic manifestations, the majority of reports deal with adult populations. We report the cut-off values (in AU, international PL units, and international units for β2GP-I) of the specific serologic response of true aCL, aCL-bovine β2GP-I, aCL-human β2GP-I, and anti-human β2GP-I in healthy Mexican children.