Association of IL-10 level and IL-10 promoter SNPs with specific antibodies in penicillin-allergic patients

Abstract

Our aim was to investigate the hypothesis that the sera interleukin-10 (IL-10) level and polymorphic nucleotides within the IL-10 gene promoters would link to specific IgE and IgG production and the expression of penicillin allergy. One hundred and two patients and 86 healthy subjects were chosen for assay of serum IL-10 level by enzyme-linked immunosorbent assay (ELISA) and type -1082 G/A and -819 C/T alleles by sequence-specific primer polymerase chain reaction (SSP-PCR). Radioallergosorbent test (RAST) and ELISA were used to examine eight types of specific immunoglobulin-E (IgE) and IgG antibodies, respectively, which included four types of antibodies to major and minor antigenic determinants. Compared with control subjects and patients with negative-specific IgE, there were significantly lower levels of IL-10 in patients with positive-specific IgE (P < 0.05). Similarly, there were significantly lower levels of IL-10 in patients with positive-specific IgG compared with normal controls and allergic patients with negative-specific IgG (P < 0.05). The visible negative correlations existed between IL-10 and four types of specific IgE [benzylpenicilloyl (BPO), phenoxomethylpenicilloyl (PVO), benzylpenicillanyl (BPA), amoxicillanyl (AXA)], and patients with three or more positive-specific IgE had significantly lower IL-10 levels than normal controls (P < 0.01). There was a declining trend for IL-10 level in serum with the increase in types of positive-specific IgE. But there was no significant difference in serum IL-10 level between the positive skin-test group and the allergic-history group. Compared with controls and patients with negative antibodies, a significantly decreased frequency of the -1082 G allele was present in patients with positive antibodies (P < 0.01). The allele T and TT genotype at -819 C/T position had lower frequency in the negative-specific IgG group than that in the positive group and controls (P < 0.01). Positive specific IgE and IgG are associated with decreased IL-10 level in allergic reaction to penicillins. The distributions of genotype and frequency of allele at the -1082 G/A position may be associated with the production of both specific IgE and IgG antibodies.