Interferon Alpha mRNA level and subtypes in lesion and non-lesion from discoid lupus erythematosus patients without systemic lupus erythematosus.

Background: Up-regulation of interferon alpha (IFN-?) in cutaneous lesions of lupus erythematosus (LE) has been proposed to play a role in the pathogenesis of cutaneous LE lesions of LE patients. IFN- ? is composed of 13 subtypes of immunoregulatory cytokines that promote innate and adaptive immune responses. However, the precise biological properties may differ among subtypes. Objective: To investigate the mRNA level of IFN-? and subtypes in cutaneous LE patients Methods: We analyzed the mRNA level of IFN-? and subtypes in normal skin from 12 healthy female controls and compared it to normal skin and discoid lupus erythematosus (DLE) lesions from 16 DLE patients without systemic involvement (14 females and 2 males) by real-time PCR, cloning, and sequencing. Results: Significant up-regulation of mRNA level of IFN-? was found in both lesional and non-lesional skin from DLE patients without SLE when compared to normal skin from healthy donors (P=0.05 and P=0.04, respectively). An analysis of the IFN-? subtypes from skin biopsies detected a reduction of IFN-? subtype 5 in DLE lesion compared to healthy control skin. Conclusions: Our results indicate that IFN- ? is upregulated in both lesional and non-lesional DLE in cutaneous LE patients. IFN-? subtype 5 is the main subtype of IFN- ? expression in normal skin but declines in DLE.

Result of standard patch test in patients suspected of having allergic contact dermatitis.

Contact dermatitis is a common skin disease. Disease was diagnosed by a history of contact substance together with geographic distribution of lesion. Up till now, standard patch test is one of the most reliable test to identify and confirm causative agent of allergic contact dermatitis. To determine the rate of positive standard patch test and to identify the common allergen of contact dermatitis in Thailand, we performed the standard patch test in 129 patients, suspected having allergic contact dermatitis at Department of Dermatology, King Chulalongkorn Memorial Hospital, Thailand from June 1, 2003 to September 1, 2004. The rate of positive standard patch test is 59.7% (n = 77/129). The most 3 common positive allergens were nickel sulfate (18.60%), cobalt chloride (17.05%) and fragrance mix (14.73%), respectively. The chance of positive standard patch test significantly correlated with sex (woman), initial diagnosis as contact dermatitis and history of house-worker (p = 0.017, p = 0.005 and p = 0.023, respectively). Whereas, there were no significant correlation between the chance of positive standard patch test and age of patient, location of lesion, history of recurrence, history of atopy, history of drug and food allergy. In addition, history of metal allergy significantly correlated with the chance of positive nickel sulfate or cobalt chloride in standard patch test (p = 0.017). In conclusion, this study demonstrated the prevalence of causative allergen of contact dermatitis in Thai patients using that standard patch test. Moreover, our data shown that the chance positive standard patch test was greater in patient, who were women or initial diagnosed as contact dermatitis or had history of houseworker or history of metal allergy.

The distribution of IL-10 promoter polymorphism in Thais.

IL-10 is a regulatory cytokine, which plays important roles in the pathogenesis of many diseases polymorphism of IL-10 promoter influences the phenotypic expressions such as the variation of IL-10 production among individuals and is subjected to the genetic susceptibility study of many diseases. However, there is no information about the frequencies of IL-10 promoter polymorphism in a Thai population. To determine the distribution of IL-10 promoter polymorphism in unrelated healthy Thais, genomic-DNA from 160 unrelated healthy volunteers were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The functional single-nucleotide polymorphisms (SNPs) in IL-10 promoter (positions -1082 (G/A), -819 (C/T), -592 (C/A) were included. The allele frequencies of -1082*A (93.4%), -819*T (71.9%), and -592*A (71.9%) were significantly higher than the allele frequencies of -1082*G (6.6%), -819*C (28.1%), and -592*C (28.1%) respectively in a Thai population similar to other Asian populations (Korean, Japanese, Chinese). As for the haplotype analysis, the ATA haplotype (72%) was significantly higher in Thais and other Asian populations compared to non-Asian populations; whereas, GCC haplotype (6.6%) was significantly lower in Thais. Additionally, two rare haplotypes of IL-10 promoter (ATC and ACA) which were previously reported only in the Chinese Han people, were found with similar frequencies (0.6%) in the present study. In conclusion, the distribution of IL-10 promoter polymorphisms in Thais was comparable to other Asian populations but distinct from Non-Asian populations. At least five haplotypes existed in an unrelated healthy Thai population as ACC, GCC, ATA, ATC, and ACA haplotypes.