Evaluation of Allergen Specific IgE assay on ADVIA Centaur Immunoassay System / 대한진단검사의학회지

BACKGROUND: Allergen specific IgE (sIgE) assay is an important aid in the diagnosis and treatment of allergy. We evaluated the analytical performance of a quantitative chemiluminescence immunoassay for sIgE using the continuous random access ADVIA Centaur. METHODS: Six ADVIA Centaur sIgE reagents for common inhalant allergens in Korea, d1, d2, e1, e5, t3, and t7, were evaluated for precision, dilution recovery (parallelism), comparison with Pharmacia UniCAP sIgE assay and skin prick test, sample volume, and analytical speed according to the NCCLS guidelines (I/LA20-A, EP5-A2). Commercialized positive and negative quality control materials were used for a precision study, and samples from a total of 110 patients were used for dilution recovery and comparison studies. RESULTS: Within-run coefficients of variation (CV) of the 6 items were 3.45-6.14% and within-device CVs (total CVs) of all items were below 10%. Interdilutional CVs of all items were 2.84-11.95%, which showed a good linearity and parallelism over its measuring range. Positive/negative concordance rates of the 6 items with UniCAP sIgE assay were 76.3-96.1% (d1, 88.2%; d2, 96.1%; e1, 91.0%; e5, 77.0%; t3, 90.5%; and t7, 76.3%). Concordance rates of the six items with skin prick test were all above 80%. The quantity of sample volume (25 micro L/test) needed was relatively small, and a high throughput (120 tests/hr) and rapid turnaround time (47 min) could be achieved. CONCLUSIONS: The ADVIA Centaur sIgE assay was thought to be a convenient and efficient method to be used in medium- to large-sized laboratories.

A Statistical Review of 3738 Cases of Skin Tumors Referred from Primary Physicians / 대한피부과학회지

BACKGROUND: Many stu iies focused on the distribution of skin tumors, but none of them included the data refered from primat y physicians in Korea. OBJECTIVE: This study was to investigate the incidence and distribution of skin tumors among Korean people. METHODS: A Total of 3738 cases of skin tumor biopsy specimens referred from primary physicians nationwide to Ewon Reference Laboratory(EWON) from July 1989 to June 1992 were reviewed with a microscope, and classified. The result was compared with the data of skin tumor cases biopsied during the same period at the department of dermatology of Asan Medical Center (AMC). RESULTS: 1. Of all skin turnors reviewed, malignant tumors were 3.9% at EWON and 11.0% at Asan Medical Center. 2. The most common primary malignant tumors of the skin were in the order of basal cell carcinoma, squamous cell carcinoma, and malignant melanoma in both centers. 3. The most common benign tumors were in the order of epidermal cyst, lipoma, pilomatricoma, hemangioma, and dermatofibroma at EWON, and epidermal cyst, seborrheic keratosis, syringoma, pyogenic granuloma, derr iatofibroma and lipoma at AMC. 4. While the prevalence of benign skin tumors were highest in the fourth & fifth decades, that of malignant skin tumorware highest in the sixth & seventh decades. CONCLUSION: Our study shows that the data obtained from tertiary hospitals can be quite different from those of primaiy physicians and the incidence of malignant skin tumors can be overestirnated when only data from large university hospitals were included.

Distribution of T lymphocyte Subpopulations in Psoriatic Skin / 대한피부과학회지

BACKGROUND: Although the main features of psoriasis consist of abnormal epidermal proliferation and T cell infiltration, which of these is the initial abnormality has been a longstanding unresolved question. Recently there has been definite evidence that activated T cells produce the cytokines that induce keratinocyte abnormalities. OBJECTIVE: We investigated the distributions and relative numbers of T lymphocyte subpopulations, that is, CD4+ and CD8+ T cells, to verify the more important T cell subtype and its infiltrating site in the formation of psoriatic lesions. METHODS: Paired psoriatic lesional and non-lesional skin tissues were obtained from eight typical psoriatic patients. Immunohistochemical staining was done on the frozen sections using a labelled streptavidin-biotin peroxidase complex method with DAKO LSAB kit. The primary antibodies used in this study were monoclonal or polyclonal antibodies against CD3, CD4, CD8, HLA-DR, and ICAM-1. RESULTS: In lesional psoriatic skin, the epidermis was mainly infiltrated by CD8+ T cells. There were little or no T cells in non-lesional epidermis. In both lesional and non-lesional dermis, CD4+ T cells were the main ones. In lesional skin, anti-ICAM-1 antibody positively stained diffusely in the endothelial cells of papillary and subpapillary plexuses and focally in epidermal keratinocytes, but in non-lesional skin only the endothelial cells in the subpapillary plexus were stained. There were many HLA-DR+T lymphocytes in lesional and non-lesional dermis. In the epidermis, HLA DR was detected only in lesional keratinocytes and T lymphocytes. CONCLUSION: These results suggest (1) participation of activated epidermal CD8+ T lymphocytes in the formation of psoriatic plaques, and (2) a pathogenetic role of ICAM-1 expression on papillary microvessels.

Detection of Herpes Simplex Virus Type-1 DNA by In Situ Polymerase Chain Reaction

BACKGROUND: Standard solution-phase PCR cannot localize the amplified DNA products in cells or tissue sections. Recently, in situ PCR technique which combines PCR with in situ hybridization was developed and applied to detect target DNA or gene expression in the tissue sections. OBJECTIVE: The purpose of this study was to detect the presence of HSV type-1 DNA in herpes simplex lesions by using hot start PCR in situ hybridization and hot start in situ PCR and to compare the sensitivity and specificity of the two methods. The sensitivity and specificity of multiple overlapping primers and a single primer pair in hot start in situ PCR were also compared. METHODS: We performed hot start PCR in situ hybridization and in situ PCR with multiple overlapping primers, and hot start in situ PCR with a single primer pair in paraffin-embedded, formalin-fixed tissues. RESULTS: HSV type-1 DNA was detected in 4 (80%) of.5 cases of herpes simplex and negative in all cases of herpes zoster, verruca vulgaris, and normal skins. One negative case of herpes simplex could not be detected by HSV type-1 specific primers because it might be caused by HSV type-2. There was no difference in the sensitivity, specificity, and intensity of signals between the three methods. CONCLUSION: Hot start in situ PCR with a single primer pair is a simpler, easier, and more rapid technique for detecting the HSV type-1 DNA in lesional tissue sections with similar sensitivity and specificity than hot start PCR in situ hybridization and hot start in situ PCR using multiple overlapping primers.

Molecular Epidemiology of Korean Isolates of Molluscum Contagiosum Virus / 대한피부과학회지

BACKGROUND: Recent restriction enclonuclease analysis studies hsve revealed that MCV DNA can be classified into two major types, designated MCV-1 and MCV-2, by th:ir restriction enzyme cleavsge patterns. In earlier reports of MCV DNA analysis, MCV-2 was the main virus type found in genital lesions. However many recent studies cienied the relationship between virus type and anatomical distribution. OBJECTIVE: The purpose of this study was to examine the ratio of MCV-l to MCV-2 in Korean isolates of MCV DNA and the relationship between MCV subtypes and with clinical features such as anatomical location, age, sex, numiber of lesions, and atopic dermatitis. METHODS: MCV DNA extrated from 112 cases of Korean patients waa examined by restriction endonuclease analysis using Brtm HI. RESULTS: 1. MCV-1 was found in 108 of 112 (96.4%) patients and MCV-2 in of 112 (3.6%) patients. The ratio of MCV-1 to MCV-2 wss 28:1. 2. There was no significant ciprrelation between MCV subtypes and the age, sex, number of lesions, atopic dermatitis, and anatoimic loction. 3. Lesions induced by MCV-1 MCV-2 were indistinguishable on the brsis of size and form. CONCLUSION: This study showis that the ratio of MCV-1 to MCV-2 was 28:1 in Korean molluscum contagiosum patients and there was no relationship between MCV subtyies and lesional morphology or snatomical distribution.