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Notes: Background Interleukin-4 receptor α (IL-4Rα), which binds IL-4 and IL-13, is involved in signal transduction of those cytokines that lead to IgE production, and is also a key functional component of the Th2 lymphocyte phenotype.Objective To determine whether IL-4 and IL-4Rα polymorphisms are associated with susceptibility to asthma and whether there are gene–gene interactions between IL-4 and IL-4Rα polymorphisms.Methods We genotyped three groups of Korean children, consisting of 196 atopic asthmatics, 60 non-atopic asthmatics, and 100 healthy children, for an IL-4 promoter polymorphism (C-590T) and three IL-4Rα polymorphisms (Ile50Val, Pro478Ser, and Arg551Gln) using PCR-RFLP (restriction fragment length polymorphism) assays.Results The allele frequencies of the IL-4 (C/T) polymorphism and the Ile50Val and Pro478Ser polymorphisms of IL-4Rα did not differ statistically among the three groups of children. For the Arg551Gln polymorphism, the combined genotype frequency of the Arg/Gln heterozygote and the Arg/Arg homozygote was significantly higher in atopic asthmatics (27.6%) than in healthy children (16.0%) (odds ratio (OR)=1.97, 95% CI (confidence interval)=1.07–3.71). The eosinophil fraction (%) and bronchial responsiveness were higher in children with the Arg/Gln and Arg/Arg genotype than in those with the Gln/Gln genotype (P=0.036 and 0.024, respectively). In asthmatic children, combinations of the IL-4 CT/TT genotype and the IL-4Rα Arg/Gln and Arg/Arg genotypes were associated with significantly increased risk for development of asthma (OR=3.70, 95% CI=1.07–12.78, P=0.038).Conclusions In Korean children, the IL-4Rα Arg551 allele may play a role in susceptibility to atopic asthma and correlate with markers of asthma pathogenesis, including increased eosinophil fraction and enhanced bronchial hyper-responsiveness. In addition, a significant gene–gene interaction between the IL-4-590C and the IL-4Rα Arg551 allele significantly increases an individual's susceptibility to asthma.

Notes: Background Allergen-specific immunotherapy has proven to be clinically effective in the treatment of patients with atopic asthma; however, the mechanisms are still unclear. Several noted immunological changes include an increase of the allergen-specific IgG antibody, a reduction in the allergen-specific IgE antibody subsequent to transient increase, an allergen-specific T cell shift in cytokine production from Th2 to Th1, and a decrease in quantity and activity of basophils and mast cells.Objective To analyse the changes of basophil histamine release in response to IgE-mediated and non-IgE-mediated stimuli before and after conventional house-dust mite immunotherapy in children who suffer from atopic asthma.Methods Fourteen Dermatophagoides farinae (Df) sensitive asthmatic children with conventional immunotherapy were examined. Basophil histamine releasability was measured 0 months (just before immunotherapy), 4 months and 9 months after immunotherapy. Basophils were stimulated with Df and goat anti-human IgE antibody as IgE-mediated stimuli; and formyl-Met-Leu-Phe (fMLP) and calcium ionophore A23187 as non-IgE-mediated stimuli. Accordingly, the asthma symptom score was used to assess clinical outcome and the skin test reactivity to Df was measured.Results In contrast to pre-immunotherapy activity, 4 and 9 months after immunotherapy there were significant decreases in histamine release by Df and by anti-IgE antibody. The histamine release by fMLP and by calcium ionophore showed no significant changes after immunotherapy. Histamine release by Df demonstrated significant correlation to that by anti-IgE antibody and by fMLP, yet there was no observable correlation between histamine release by Df and by calcium ionophore. The asthma symptom score decreased significantly 4 and 9 months after immunotherapy and showed significant correlation with histamine release by Df. The skin test reactivity (allergen/histamine ratio) remained constant 4 months after immunotherapy, but decreased significantly 9 months after immunotherapy.Conclusion Basophils have the potential to play an important role in the early clinical improvement of conventional immunotherapy in children with atopic asthma, which may be a result of the decreased IgE-mediated histamine releasability during immunotherapy.

Notes: Background There are racial differences in the prevalence and types of androgenetic alopecia (AGA). There have been several reports on the prevalence and types of AGA in the general population of caucasians, but few studies on Koreans with samples of sufficient numbers have been reported.Objectives To obtain a more precise estimate of the prevalence and types of AGA in Korean men and women and to compare the results with those in caucasians.Methods The prevalence and types of AGA were analysed in 10,132 Koreans (5531 men and 4601 women) who had visited the Health Examination Centre at Kyung Hee University Hospital for regular health examinations between December 1997 and July 1999. To classify the degree of hair loss for each subject, the Norwood classification was used in men and the Ludwig classification in women. For AGA in men, ‘female pattern’ was added to the Norwood classification.Results In Korean men, the prevalence of AGA (Norwood III or above) at all ages was 14·1%. It increased steadily with advancing age, but was lower than that of caucasians: 2·3% in the third decade, 4·0% in the fourth decade, 10·8% in the fifth decade, 24·5% in the sixth decade, 34·3% in the seventh decade and 46·9% over 70 years. Type III vertex involvement was the most common type in the third decade to the seventh decade; over 70 years, type VI was most common. A ‘female pattern’ was observed in 11·1% of cases. In Korean women, the prevalence of AGA (Ludwig I or above) at all ages was 5·6%. It also increased steadily with advancing age: 0·2% in the third decade, 2·3% in the fourth decade, 3·8% in the fifth decade, 7·4% in the sixth decade, 11·7% in the seventh decade and 24·7% over 70 years. Grade I was the most common type up to the sixth decade; over 60 years, grade I and II were similar in prevalence. Grade III (total baldness) was not observed. A family history of baldness was present in 48·5% of men and 45·2% of women with AGA.Conclusions The prevalence of AGA in Korean men and women was lower than that in caucasians, as recorded in the literature. Korean men tend to have more frontal hairline preservation and show a more ‘female pattern’ of hair thinning than caucasians. Therefore, ‘female pattern’ should be added to the classification of AGA.

Notes: Previously, the arginine at hen egg-white lysozyme 61 (HEL 61) was characterized as inhibiting T-lymphocyte stimulation due to the inefficient binding of the arginine-containing epitope peptide to the corresponding major histocompatibility complex class II molecules in C57BL/6 mice. In this study, we produced recombinant HEL, with arginine or alanine at HEL 61, and compared its ability to induce immune responses in mice to see whether modification of an inhibitory amino acid could enhance the immunogenicity of an inefficient antigen. Immunization of the mice with modified HEL induced strong antibody and T-cell immune responses against the native antigen. The enhanced T-cell immune response was due to a more specific elevation of the T-cell responses to the HEL 46–61 epitope region than to other epitope regions, although recognition of the other epitope peptides of HEL was generally increased. Mass spectrometric analyses of the epitope peptides generated by splenic antigen-presenting cells indicated that production of the epitope peptides encompassing HEL 46–61 was efficient using the modified antigen. These results suggest that modification of the critical amino acid residue(s) involved in hampering induction of an efficient immune response is an effective method to improve the immunogenicity of an inefficient antigen.

Notes: This study was undertaken to investigate the immunohistochemical characterization of different subpopulations of macrophages and dendritic cells (DCs) of the spleen, thymus, tongue and heart in cyclophosphamide (CY)-induced immunosuppressed rat. After CY treatment, remarkably, ED1+, ED2+ and ED3+ macrophage subpopulations, in general, exhibited signs of cellular activation such as an increase in number and size of cell, and an upregulation of the ED1, ED2 and ED3 reactive surface molecule expression in all the organs studied, except for some macrophage subpopulations including ED1+ macrophages in the non-lymphoid tissues. Subpopulations of DCs showed a differential sensitivity to CY. Lymphoid DCs were more sensitive to CY than non-lymphoid interstitial DCs. CY induced a conspicuous upregulation of intercellular adhesion molecule-1 (ICAM-1) expression in the vascular endothelial cells, splenic marginal zone and thymic cortex. In this study, we demonstrated the in vivo effects of CY treatment on subpopulations of macrophages and DCs as well as on ICAM-1 expression in the rat spleen, thymus, tongue and heart. Moreover, our results shed more light on the activation effects of CY on certain subpopulations of macrophages, on the differential sensitivity of DCs to CY between the immature and mature ones, on the functional role of different subpopulations of macrophages, and on the significance of upregulated ICAM-1 expression in the splenic marginal zone and thymic cortex after CY treatment.