Serum Polyclonal Immunoglobulin E Levels among an Apparently Healthy Iraqi Population: A Preliminary Report

Abstract

The distribution of serum polyclonal IgE levels as determined by paper radioimmunosorbent test was studied in 150 nonallergic, presumably healthy individuals. Prior to natural logarithmic conversion, the distribution was strongly skewed to the left, and normal distribution followed logarithmic conversion. The range of serum polyclonal IgE levels was 1 to 2439 μg/L with a geometric mean value of 197 μg/L. Regression analysis of natural logarithm of serum polyclonal IgE levels with age revealed no significant association. Higher levels were demonstrated among individuals 10 to 14 years old than among other age groups. Variation of IgE levels among individuals and patients stemmed from differences in race, 24 age and sex, 6,25,26 assay methods, 27 and other factors including infections. Discrepancies in various studies may be due to poor definition of the study population, variability of environmental factors, use of nonstandardized reagents, and different statistical methods.This study is a preliminary report on the serum polyclonal IgE levels in a nonallergic presumably healthy Iraqi urban population. Materials and MethodsVenous blood samples were obtained from 150 apparently healthy subjects attending Al-Waih Pediatric Hospital to vaccinate their children. They gave no history of allergy, and their stool and urine examination revealed no helminthic infection. The mean age of these individuals was 26 ± 14.5 years (ranging from 8 months to 65 years) Serum Polyclonal Immunoglobulin E Levels Among an Apparently Healthy Iraqi Population: A Preliminary Report Annals of Saudi Medicine, Vol 9 No. 2; 1989with a male-to-female ratio of 1.3:1. Sera were separated from clotted blood by cen-trifugation, divided into aliquots, and stored at -20°C. Serum polyclonal IgE levels were determined by paper radioimmunosorbent test as described by Gleich et al, 28 using commercially available kits. Serum samples were assayed in duplicate within the same batch, and the values recorded were the mean of two determinations. In brief, anti-IgE coated filter paper disks were incubated overnight with test serum. After three washings, each disk was incubated with anti-IgE-125 I. After three more washings, the radioactivity percent on each disk was measured in a gamma counter. Results were expressed as percentage binding (the ratio between count per minutes of each disk and total radioactivity).The results were evaluated statistically by the Student t test and analysis of variance. P values less than 0.05 were considered statistically significant. ResultsThe frequency distribution of serum polyclonal IgE was strongly skewed to the left (Figure 1) with almost 31.3% of values below 120 μg/L. The data were transformed to natural logarithm to get a normal distribution (Figure 2).

Effect of Surgical Removal of Hydatid Cyst on Echinococcus-Specific and Polyclonal Ige Antibodies: An Aid for Postoperative Follow-Up Studies

“…In a previous communication, the geometric mean level of the total IgE was estimated to be 197 μg/L among non-allergic helminth-free Iraqi population [19]. In contrast, the present communication demonstrated a markedly elevated serum level of polyclonal IgE among patients with hydatid disease.…”

Helminth-Specific IgE and Extrinsic Allergen-Specific IgE in Patients with Atopic Diseases

“…[1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][38][39][40] In a previous communication, the geometric mean level of serum polyclonal IgE among nonatopic helminth-free healthy individuals of the same community has been estimated to be 297 μg/L. 41 This is lower than that observed in our atopic subjects either with or without helminth-specific IgE. In conclusion, the data presented in this report do not support the hypothesis that helminth-induced IgE in atopic subjects protects against subsequent allergic reactions.…”