Serum eosinophil cationic protein (ECP) and eosinophil protein X (EPX) in childhood asthma: The influence of atopy

Abstract

The purpose of this study was to determine the value of serum measurements of eosinophil cationic protein (ECP) and eosinophil protein X (EPX) in diagnosing asthma in children, and to investigate the influence of concomitant allergic diseases and atopic sensitization, assessed by skin prick tests (SPT), on these markers. ECP and EPX were determined in 36 children with asthma, in 33 children with other symptoms from lower airways disease (OSLA), and in 166 control children. Sixteen children with asthma but no anti‐inflammatory therapy had significantly higher concentrations of ECP and EPX (ECP: 27.5 μg/L, P < 0.001; EPX: 59.9 μg/L, P < 0.001) than the control children (ECP: 11.2 μg/L; EPX: 26.2 μg/L). In the 20 children on anti‐inflammatory therapy, ECP values were similar to those of controls. The children with OSLA (ECP: 13.6 μg/L, P < 0.01; EPX: 47.2 μg/L, P < 0.001) differed significantly from controls. When using the value of 24.7 μg/L (97.5 percentile in the 68 non‐atopic controls) as a pathologic upper limit for ECP, 10 (63%) of the 16 asthmatic children on no maintenance medication, two (10%) of the 20 asthmatics on maintenance therapy, and 11 (33%) of the 33 children with OSLA had high ECP; the same figure was only 18 (11%) in the 166 control children. Both ECP and EPX had a significant association with allergic disorders and with SPT reactivity. In multivariate logistic regression analysis, an elevated ECP was significantly associated with asthma (OR 2.3, 95%Cl 1.1–4.9) and atopic dermatitis (2.9, 1.2–6.9), and an elevated EPX was significantly associated with asthma (2.61, 1.19–5.74) and allergic rhinoconjunctivitis (5.23, 1.46–18.73). We conclude that serum concentrations of both ECP and EPX are higher in asthmatic than in healthy children. However, other allergic diseases, such as allergic rhinoconjunctivitis, atopic dermatitis, and allergic skin sensitization also raise the concentrations of these markers. This limits their usefulness in the diagnosis of childhood asthma. Pediatr. Pulmonol. 1998; 25:167–174. © 1998 Wiley‐Liss, Inc.

Eosinophil-derived neurotoxin acts as an alarmin to activate the TLR2–MyD88 signal pathway in dendritic cells and enhances Th2 immune responses

“…EDN is likely to be generated and present at sites of inflammation associated with such disorders. EDN is present in the serum and nasal lavage fluid of healthy individuals at ∼20 ng/ml ( 58 , 59 ), but its concentration in the nasal lavage fluid of patients with allergic rhinitis can reach as high as 880 ng/ml ( 60 ), suggesting that EDN in tissues subject to allergic reaction or parasitic infection can reach a concentration (100∼1,000 ng/ml) necessary for the activation of DCs and enhancement of immune response described in the present study. Therefore, the capacity of EDN to activate DCs and to enhance a Th2-polarized immune response may provide a basis for the induction and/or maintenance of a Th2-polarized immune response during parasitic infection, allergy, or atopic reaction.…”

Diagnostic value of skin‐prick and patch tests and serum eosinophil cationic protein and cow's milk‐specific IgE in infants with cow's milk allergy

“…Although the increase in serum ECP during the challenge was significant in infants with CMA and not in those with a negative challenge, the test did not discriminate between the challenge-positive and -negative infants at low cut-off values. However, the small number of high values (> 24.7 mg/L) [16] were mostly confined to the infants with CMA. Others have measured the postchallenge ECP earlier than we did in the present study [8,24].…”

“…CM-specific IgE were measured in 233 available single samples and serum ECP in 156 available paired samples by the Pharmacia CAP system (Pharmacia & Upjohn Diagnostics, Uppsala, Sweden). The following cut-off values were selected for serum ECP measured on challenge day 4: > 15 mg/L (suggested by the manufacturer) [14], > 20 mg/L [15] and > 24.7 mg/L [16].…”

DNA methylation loci associated with atopy and high serum IgE: a genome-wide application of recursive Random Forest feature selection

“…EPX encodes eosinophil peroxidase, a protein expressed by eosinophils. Previous investigations found that both serum and urine levels of EPX were elevated in children who had positive SPTs, as well as those with allergic diseases such as asthma, allergic rhinoconjunctivitis and atopic dermatitis [ 48 – 51 ]. A recent epigenome-wide study found multiple CpG sites, including one within PRG2 , which were associated with high versus low total IgE, primarily driven by eosinophils.…”