Lactobacillus plantarum-derived Extracellular Vesicles Protect Atopic Dermatitis Induced by Staphylococcus aureus-derived Extracellular Vesicles

PURPOSE: The microbial environment is an important factor that contributes to the pathogenesis of atopic dermatitis (AD). Recently, it was revealed that not only bacteria itself but also extracellular vesicles (EVs) secreted from bacteria affect the allergic inflammation process. However, almost all research carried out so far was related to local microorganisms, not the systemic microbial distribution. We aimed to compare the bacterial EV composition between AD patients and healthy subjects and to experimentally find out the beneficial effect of some bacterial EV composition METHODS: Twenty-seven AD patients and 6 healthy control subjects were enrolled. After urine and serum were obtained, EVs were prepared from samples. Metagenomic analysis of 16s ribosomal DNA extracted from the EVs was performed, and bacteria showing the greatest difference between controls and patients were identified. In vitro and in vivo therapeutic effects of significant bacterial EV were evaluated with keratinocytes and with Staphylococcus aureus-induced mouse AD models, respectively. RESULTS: The proportions of Lactococcus, Leuconostoc and Lactobacillus EVs were significantly higher and those of Alicyclobacillus and Propionibacterium were lower in the control group than in the AD patient group. Therefore, lactic acid bacteria were considered to be important ones that contribute to the difference between the patient and control groups. In vitro, interleukin (IL)-6 from keratinocytes and macrophages decreased and cell viability was restored with Lactobacillus plantarum-derived EV treatment prior to S. aureus EV treatment. In S. aureus-induced mouse AD models, L. plantarum-derived EV administration reduced epidermal thickening and the IL-4 level. CONCLUSIONS: We suggested the protective role of lactic acid bacteria in AD based on metagenomic analysis. Experimental findings further suggest that L. plantarum-derived EV could help prevent skin inflammation.

A Metagenomic Analysis Provides a Culture-Independent Pathogen Detection for Atopic Dermatitis

PURPOSE: Atopic dermatitis (AD) is an inflammatory skin disease, significantly affecting the quality of life. Using AD as a model system, we tested a successive identification of AD-associated microbes, followed by a culture-independent serum detection of the identified microbe. METHODS: A total of 43 genomic DNA preparations from washing fluid of the cubital fossa of 6 healthy controls, skin lesions of 27 AD patients, 10 of which later received treatment (post-treatment), were subjected to high-throughput pyrosequencing on a Roche 454 GS-FLX platform. RESULTS: Microbial diversity was decreased in AD, and was restored following treatment. AD was characterized by the domination of Staphylococcus, Pseudomonas, and Streptococcus, whereas Alcaligenaceae (f), Sediminibacterium, and Lactococcus were characteristic of healthy skin. An enzyme-linked immunosorbent assay (ELISA) showed that serum could be used as a source for the detection of Staphylococcus aureus extracellular vesicles (EVs). S. aureus EV-specific immunoglobulin G (IgG) and immunoglobulin E (IgE) were quantified in the serum. CONCLUSIONS: A metagenomic analysis together with a serum detection of pathogen-specific EVs provides a model for successive identification and diagnosis of pathogens of AD.

Helicobacter pylori-derived extracellular vesicles increased in the gastric juices of gastric adenocarcinoma patients and induced inflammation mainly via specific targeting of gastric epithelial cells

Evidence indicates that Helicobacter pylori is the causative agent of chronic gastritis and perhaps gastric malignancy. Extracellular vesicles (EVs) play an important role in the evolutional process of malignancy due to their genetic material cargo. We aimed to evaluate the clinical significance and biological mechanism of H. pylori EVs on the pathogenesis of gastric malignancy. We performed 16S rDNA-based metagenomic analysis of gastric juices either from endoscopic or surgical patients. From each sample of gastric juices, the bacteria and EVs were isolated. We evaluated the role of H. pylori EVs on the development of gastric inflammation in vitro and in vivo. IVIS spectrum and confocal microscopy were used to examine the distribution of EVs. The metagenomic analyses of the bacteria and EVs showed that Helicobacter and Streptococcus are the two major bacterial genera, and they were significantly increased in abundance in gastric cancer (GC) patients. H. pylori EVs are spherical and contain CagA and VacA. They can induce the production of tumor necrosis factor-α, interleukin (IL)-6 and IL-1β by macrophages, and IL-8 by gastric epithelial cells. Also, EVs induce the expression of interferon gamma, IL-17 and EV-specific immunoglobulin Gs in vivo in mice. EVs were shown to infiltrate and remain in the mouse stomach for an extended time. H. pylori EVs, which are abundant in the gastric juices of GC patients, can induce inflammation and possibly cancer in the stomach, mainly via the production of inflammatory mediators from gastric epithelial cells after selective uptake by the cells.

House Dust Mite-Derived Chitin Enhances Th2 Cell Response to Inhaled Allergens, Mainly via a TNF-α-Dependent Pathway

PURPOSE: Chitin is a potent adjuvant in the development of immune response to inhaled allergens in the airways. According to other studies, chitin is known as multi-faced adjuvants which can induce Th2 responses. Recently, we found that TNF-α is a key mediator in the development of Th2 cell response to inhaled allergens. Here, we evaluated the immunologic mechanisms in the development of airway hypersensitivity to inhaled allergens, enhanced by house dust mite (HDM)-derived chitin. METHODS: The role of TNF-α and TLRs was evaluated in an airway hypersensitivity mouse model induced by a sensitization with an allergen (ovalbumin, OVA) and HDM-derived chitin using mice with the null mutation of target genes. RESULTS: The present study showed that airway sensitization with HDM-derived chitin plus OVA enhanced OVA-induced airway inflammation v. OVA alone. This phenotype was associated with the increased expression of Th1, Th2, and Th17 cytokines and also with the enhanced production of OVA-specific IgE, IgG1, and IgG2a. As for T cell responses, OVA-specific Th2 cell response, enhanced by chitin, was abolished by the treatment of chitinase, whereas Th1 and Th17 cell responses enhanced by this treatment. Moreover, the null mutation of the TNF-α gene revealed similar effects as the chitinase treatment. In contrast, all the OVA-specific T cell responses, enhanced by chitin, were blocked by the absence of TLR2, but not of TLR1, TLR4, or TLR6. CONCLUSIONS: In conclusion, these data suggest that HDM-derived chitin may enhance airway hypersensitivity to inhaled allergens, via the TLR2-dependent pathway, and that chitin-induced TNF-α can be a key mediator in the development of Th2 cell response to inhaled allergens.

Vaccination with Klebsiella pneumoniae-derived extracellular vesicles protects against bacteria-induced lethality via both humoral and cellular immunity

The emergence of multidrug-resistant Klebsiella pneumoniae highlights the need to develop preventive measures to ameliorate Klebsiella infections. Bacteria-derived extracellular vesicles (EVs) are spherical nanometer-sized proteolipids enriched with outer membrane proteins. Gram-negative bacteria-derived EVs have gained interest for use as nonliving complex vaccines. In the present study, we evaluated whether K. pneumoniae-derived EVs confer protection against bacteria-induced lethality. K. pneumoniae-derived EVs isolated from in vitro bacterial culture supernatants induced innate immunity, including the upregulation of co-stimulatory molecule expression and proinflammatory mediator production. EV vaccination via the intraperitoneal route elicited EV-reactive antibodies and interferon-gamma-producing T-cell responses. Three vaccinations with the EVs prevented bacteria-induced lethality. As verified by sera and splenocytes adoptive transfer, the protective effect of EV vaccination was dependent on both humoral and cellular immunity. Taken together, these findings suggest that K. pneumoniae-derived EVs are a novel vaccine candidate against K. pneumoniae infections.

Acetyl salicylic acid inhibits Th17 airway inflammation via blockade of IL-6 and IL-17 positive feedback

T-helper (Th)17 cell responses are important for the development of neutrophilic inflammatory disease. Recently, we found that acetyl salicylic acid (ASA) inhibited Th17 airway inflammation in an asthma mouse model induced by sensitization with lipopolysaccharide (LPS)-containing allergens. To investigate the mechanism(s) of the inhibitory effect of ASA on the development of Th17 airway inflammation, a neutrophilic asthma mouse model was generated by intranasal sensitization with LPS plus ovalbumin (OVA) and then challenged with OVA alone. Immunologic parameters and airway inflammation were evaluated 6 and 48 h after the last OVA challenge. ASA inhibited the production of interleukin (IL)-17 from lung T cells as well as in vitro Th17 polarization induced by IL-6. Additionally, ASA, but not salicylic acid, suppressed Th17 airway inflammation, which was associated with decreased expression of acetyl-STAT3 (downstream signaling of IL-6) in the lung. Moreover, the production of IL-6 from inflammatory cells, induced by IL-17, was abolished by treatment with ASA, whereas that induced by LPS was not. Altogether, ASA, likely via its acetyl moiety, inhibits Th17 airway inflammation by blockade of IL-6 and IL-17 positive feedback.

A Case of Pregnancy in Essential Thrombocythaemia with Low dose Aspirin Treatment / 대한주산의학회잡지

Essential thrombocythaemia (ET) is a chronic myeloproliferative disorder characterized by markedly elevated platelet count in the peripheral blood due to an excessive proliferation of bone marrow megakaryocytes. The pregnancy outcome among patients with ET is mostly successful but adverse outcome due to thrombotic and bleeding complications is a matter of concern: miscarriage, intrauterine growth retardation, abruptio placenta, intrauterine fetal death and preterm delivery. Various treatments such as acetylsalicylic acid, hydroxyurea, anagrelide, heparin, interferon alpha and plateletpheresis have been proposed to improve the pregnancy outcome. We report a case of pregnant woman in condition of ET who succeeded in normal vaginal delivery without specific obstetric complications after low dose aspirin therapy during pregnancy.

A Case of Ureteral Endometriosis associated with Hydronephrosis / 대한산부인과학회지

Endometriosis affecting the urinary tract is very rare disease. The ureteral endometriosis is mostly asymptomatic for a long time, and associated with nonspecific symptoms such as abdominal or flank pain, renal colic, voiding difficulty and gross hematuria. Radiologic and laboratory findings show nonspecific findings, and the diagnosis is difficult. We report a case of obstructive ureteral endometriosis associated with right hydronephorsis. This case is operated under the impression of direct compression of ureter by uterine myoma. Total abdominal hysterectomy and ureteroureterostomy were performed. Final diagnosis of ureteral endometriosis is documented by pathologic findings.

A Case of Juvenile Granulosa Cell Tumor of the Ovary / 대한산부인과학회잡지

Juvenile granulosa cell tumor is a well-known sex-cord stromal ovarian neoplasm different in appearance and behavior from the adult granulosa cell tumor and occurs most (80%) frequently in the first two decades. The prognosis of juvenile granulosa cell tumor in children is good in most cases, but correlated with stage, size, the presence of ruptures, the grade of nuclear atypia, the degree of mitotic activity. The surgery remains the principal line of treatment for low stage juvenile granulosa cell tumor in children, but for those patient with high stage juvenile granulosa cell tumor or recurrence, the best treatment has yet to be determined and tumor sensitivity to radiation therapy and chemotherapy is not clearly. We present a case of juvenile granulosa cell tumor with brief review of literatures.

Clinical Evaluation of Ovarian Tumors in Pregnancy / 대한산부인과학회잡지

OBJECTIVE: We performed this study to evaluate the clinical appearance of ovarian timor in pregnancy. MATERIALS AND METHODS: From January 1995 to December 2000, a review was performed 51 cases of ovarian tumors in pregnancy. The diagnosis of ovarian tumor was confirmed by pathologist after operation. RESULTS: 1. The incidence of ovarian tumors in pregnancy was 51 in 11,056 deliveries (1:217). Five cases of borderline malignancy and one case of granulosal cell tumor were reported. 2. The ovarian tumors were the most common between 30 and 34 years of age pregnant women (35.5%) and more common in multiparous women than in nulliparous women. 3. As to the initial chief complaints, no symptoms and sign were in 36 cases (70.6%) low abdominal pain and discomfort were in 6 cases (11.8%) palpable mass were found in 2 cases (3.9%). 4. 53% of patients was diagnoses in the third trimester, 33.3% of patients in the first trimester, 13.7% of patients in the second trimester. 5. Excluding the 27 cases of incidental operation during cesarean section, operation was performed at first trimester in 4 cases (16.7%), at second trimester in 9 cases (37.5%), after conservative management operation during cesarean section was performed at third trimester in 11 cases (45.8%). 6. Complication resulting ovarian tumors occurred in one case of torsion. 7. According to histologic type, there were 15 cases (29.4%) of benign cystic teratoma, 13 cases (23.5%) of mucinous cystadenoma, 8 cases (15.7%) of serous cystadenoma, 4 cases (7.7%) of corpus luteal cyst, 5 cases (9.8%) of mucinous cystic tumor borderline malignancy, 1 case (2%) of granulosal cell tumor. 8. According to effects on pregnancy, among 13 cases in which the ovarian tumor was removed, vaginal delivery occurred at term in 6 cases (46.1%), cesarean section at term in 4 case (30.8%), missed abortion in 1 case (7.7%), preterm delivery in 2 cases (15.4%). 11 cases in which was performed conservative management were done cesarean section at term. CONCLUSION: The incidence of benign and malignant ovarian tumor in pregnancy and is being increased. Considering effects on pregnancy and pregnant women of treatment method, appropriate timing and treatment method should be chosen.

Relation of placental size to large-for-gestational-age infants in women with gestational diabetes mellitus controlled with insulin / 대한산부인과학회잡지

OBJECTIVE: To determine if the placental size is disproportionately increased in the large-for-gestational age infants in pregnancies complicated by impaired glucose tolerance controlled with insulin. PATIENS AND METHODS: A retrospective study was performed on 104 singleton pregnancies complicated by gestational impaired glucose tolerance controlled with insulin. The cases were categorized by the infant birthweight percentile into three groups, i.e. small-for-gestational age (90th percentile). Maternal and infant anthropometric data, glycemic status, and placental weight-to-birthweight ratio were compared among three groups. RESULTS: The maternal glucose level just after delivery, infant body mass index and placental weight showed a significant increment from the small-for-gestational age to the large-for-gestational age groups (p<0.05). The placental weight-to-birthweight ratio was significantly higher in the small-for-gestational group. On the other hand, there was no significant difference in the values of the oral glucose test, hemoglobin A1c and maternal body mass index among three groups. Maternal body mass index showed a increasing trend from the small-for gestational age to the large-for-gestational age groups. Placental weight-to-birthweight ratio was not significantly correlate with maternal glucose level. CONCLUSIONS: The results indicate that the placenta is disproportionately bigger, and rigid control of maternal blood glucose does not prevent the development of placental overgrowth. Maternal obesity in well- controlled gestational diabetes mellitus may be more significant than glucose control in the development of large-for-gestational-age infants. Different management strategies for women with gestational diabetes mellitus with different pregravid weights are warranted.

A Clinical Study of Borderline Malignant Tumors of the Ovary / 대한산부인과학회잡지

OBJECTIVE: The purpose of this study was to review the clinical features, treatments and prognosis of the borderline malignant tumors of the ovary. METHODS: Thirty-two patients with borderline malignant tumors of the ovary were admitted, operated and confirmed with postoperative histopathological study at department of obstetrics and gynecology, Yonsei University Wonju Christian Hospital. The data were collected retrospectively and all charts were reviewed. RESULTS: The incidence of borderline malignant ovarian tumor was 19.2% (32/167). Age distribution revealed between 18 and 77 years old, the mean age was 43.1 years old. As for the parity distribution of borderline malignant tumor, nulliparity was most common (43.8%). The most common chief complaint was abdominal distension (34.4%). Histologic subtypes were mucinous in 19 cases (59.4%), serous in 13 cases (40.6%). According to FIGO classification, 28 cases (87.5%) were stage I, 1 case (3.1%) was stage II, 3 cases (9.4%) were stage III. Sixteen cases (50%) underwent conservative surgery (unilateral salpingooophorectomy or cystectomy). Sixteen cases (50%) were treated with total abdominal hysterectomy and bilateral salpingooophorectomy. Fifteen cases (46.9%) received adjuvant postoperative chemotherapy. Excluding 5 cases lost to follow up, patients were alive and were followed from 9 months to 100 months. (mean 36 months).

A Clinical Study of Borderline Malignant Tumors of the Ovary / 대한산부인과학회잡지

OBJECTIVE: The purpose of this study was to review the clinical features, treatments and prognosis of the borderline malignant tumors of the ovary. METHODS: Thirty-two patients with borderline malignant tumors of the ovary were admitted, operated and confirmed with postoperative histopathological study at department of obstetrics and gynecology, Yonsei University Wonju Christian Hospital. The data were collected retrospectively and all charts were reviewed. RESULTS: The incidence of borderline malignant ovarian tumor was 19.2% (32/167). Age distribution revealed between 18 and 77 years old, the mean age was 43.1 years old. As for the parity distribution of borderline malignant tumor, nulliparity was most common (43.8%). The most common chief complaint was abdominal distension (34.4%). Histologic subtypes were mucinous in 19 cases (59.4%), serous in 13 cases (40.6%). According to FIGO classification, 28 cases (87.5%) were stage I, 1 case (3.1%) was stage II, 3 cases (9.4%) were stage III. Sixteen cases (50%) underwent conservative surgery (unilateral salpingooophorectomy or cystectomy). Sixteen cases (50%) were treated with total abdominal hysterectomy and bilateral salpingooophorectomy. Fifteen cases (46.9%) received adjuvant postoperative chemotherapy. Excluding 5 cases lost to follow up, patients were alive and were followed from 9 months to 100 months. (mean 36 months).

The Expression of Vascular Endothelial Growth Factor (VEGF) is a Highly Significant Prognostic Factor in Stage IB Carcinoma of the Cervix / 대한방사선종양학회지

PURPOSE: The aim of this study was to clarify the role of VEGF expression as an independent prognostic factor and to identify the patients at high risk for poor prognosis in stage IB cervical cancer. MATERIALS AND METHODS: A total of 118 patients with stage IB cervical cancer who had radical hysterectomy and pelvic lymph node dissection were included in the study. All known high risk factors of the patients were pathologically confirmed from the surgical specimen. Of the 118 patients, 88 patients were treated with postoperative radiotherapy and/or chemotherapy. VEGF expression was examined using immunohistochemistry in formalin-fixed, paraffin-embedded specimens of post-hysterectomy surgical materials. A semiquantitative analysis was made using a scoring system of 0, +, + +, and + + + for increasing intensity of stain. We classified the patients with scores from 0 to + + as low VEGF expression and the patients with a score of + + + as high VEGF expression. RESULTS: Of the 118 patients, 35 patients (29.7%) showed high VEGF expression. Strong correlations were found between the high VEGF expression and both deep stromal invasion (p=0.01) and the positive pelvic node (p=0.03). The 5-year overall and disease-free survival rates for all 118 patients were 95.5% and 93.8%. The 5-year overall (p=0.03) and disease-free survival (p<0.001) rates were 98.5% and 100% for low VEGF expression (0, +, and + +) and 85.5% and 79.7% for high VEGF expression, respectively. Pelvic and distant failures for low versus high VEGF expression were 1.2% versus 17.1%, (p=0.001) and 0% versus 14.3% (p<0.001), respectively. In a Cox multivariate analysis of survival, the high VEGF expression (p=0.02) and the bulky mass (p=0.02) were significant prognostic factors for overall survival. The high VEGF expression (p=0.002), and bulky mass (p=0.01) demonstrated as significant prognostic indicators for disease free survival. CONCLUSION: These results showed that VEGF expression was a highly significant predictor for pelvic and distant failure and the most significant prognostic factor of overall and disease free survival for the patients with stage IB cervix cancer treated with radical surgery. We strongly suggest that the immunohistochemistry for VEGF expression be performed in a routine clinical setting in order to identify the patients at high risk for poor prognosis in early stage cervical cancer. Furthermore, postoperative and/or chemotherapy did not reduce the pelvic failure and distant metastasis. To improve the cure rate for the patients with high VEGF expression in stage IB cervical cancer, antiangiogenic therapy including anti- VEGF Ab may be a new treatment option.

A Case of Mucinous Cystadenocarcinoma Arising from a Mature Cystic Teratoma in the Right Ovary / 대한부인종양콜포스코피학회잡지

A case of mucinous cystadenocarcinoma arising from a mature cystic teratoma in the right ovary of a 37-year-old woman is reported. Malignant transformation of a mature teratoma is a rare event and the commonest malignant neoplasm to develop is squamous cell carcinoma.(83%) Adenocarcinoma occurs with less frequency.(6.8%) The patient was treated by staging operation followed by adjuvant chemotherapy. After six courses of combination chemotherapy, oncological investigations, including chest X-ray, abdominopelvic CT scan and tumor markers, all revealed no evidence of recurrence.

Clinical Study of Microinvasive Cervical Cancer / 대한산부인과학회잡지

OBJECTIVE: With the use of regular cervical cytologic screening, an increasing percent of patients with invasive cervical cancer are being diagnosed with early-stage disease. During the past two decades, there has been considerable interest in identifying a group of patients with early invasive cancer who have a minimal risk for extracervical spread. Method: From January 1993 to June 2000, we have experienced 26 cases with microinvasive cervical cancer. The data were collected retrospectively and all charts were reviewed. Result: The age ranged from 29 to 69 years and median age was 44.3 years. 18 cases incidentally found through the routine Pap smear, in symptomatic group most frequent initiating symptom was postcoital bleeding. The corresponding rate of Pap smear to histologic diagnosis was approximately 26.9%. However, corresponding rate within one histologic grade was about 69.2%. The modified radical abdominal hysterectomy was performed in 21 cases and modified radical abdominal hysterectomy with pelvic lymph node biopsy was performed in 4 cases and radical abdominal hysterectomy with pelvic node biopsy was done in 1 case with greater than 3 mm and no greater than 5 mm stromal invasion. There was no surgery-related deaths and recurrent cases in this study. CONCLUSION: The prognosis of stage Ia cervical cancer is relatively good and less radical therapeutic approach may be beneficial. But, further prospective study based on large numbers of cases with multi-institutional cooperation and designed protocol will be necessary.

Clinical Response of Uterine Embolization for the management of Leiomyomas / 대한산부인과학회잡지

OBJECTIVE: To determine of the effectiveness of uterine arterial embolization as a primary therapy in the management of symptomatic leiomyomas. MATERIALS AND METHODS: Uterine arterial embolization was performed in 23 patients (age range, 27-50 years) who complaint menorrhagia, bulk-related symptoms(frequency of urination, sensation of pressure, sensation of mass), or both, with leiomyomas. The effectiveness of the therapy was evaluated in the view of symptomatic relief and the patients' acceptance with ultrasonography, 3 months later. RESULTS: Sixteen (89%) of 18 patients reported marked improvement in their abnormal bleeding. Ten (90%) of 11 patients with bulk-related symptoms reported marked improvement in these symptoms. Follow-up ultrasonographic examination showed a mean 21% reduction in uterine size and mean 39% reduction in leiomyoma size. CONCLUSION: Utrine arterial embolization is an effective therapy in the management of symptomatic leiomyomas and may prove to be a valuable alternative to myomectomy, hysterectomy, or other surgical procedures.

A Case of Delivery of Normal Term Baby after Treatment of Gonadoblastoma with Dysgerminoma and Choriocarcinoma in the Ovary in a Woman with 46XX Karyotype / 대한부인종양콜포스코피학회잡지

A case of gonadoblastoma with dysgerminoma and choriocarcinoma in the right ovary of a 23-year-old woman is reported. A case of gonadoblastoma without a Y chromosome is very rare. She had a 46XX chromosomes, normal genitalia, no history of menstrual irregularities, thereby differing from the other reproted case. The patient had a normal term pregnancy 2 years after surgery and chemotherapy. It is suggested that gonadoblastoma may occur in functionally and morphologically normal gonads. There have been no signs of recurrence or metastasis for 3 years after the first operation.

A Case of Dysgerminoma Associated with 46, XY Pure Gonadal Dysgenesis / 대한부인종양콜포스코피학회잡지

Dysgerminoma developed in a 21-year-old phenotypic female patient with 46,XY pure gonadal dysgenesis, Swyer syndrome. This patient presented with pelvic mass associated with abdominal pain and primay amenorrhea. Clinical characteristics showed a typical stigmata of gonadal dysgenesis: primary amenorrhea, sexual infantilism, a small uterus and left streak gonad. A 46,XY karyotype was made by lymphocyte culture. The patient was counseled to undergo operation, chemotherapy and hormon therapy. She underwent bilateral gonadectomy with total hysterectomy, partial omentectomy and multiple pelvic wall random biopsy. Histological examination revealed dysgenetic gonads with dysgerminoma. After surgery, the patient received chemotherapy and also was started on hormone replacement therapy. She is currently alive with no evidence of disease after 19 months from surgery.

Comparison of HLA-B27 typing methods -PCR-SSP, microlymphocytotoxicity, and flow cytometry / 대한임상병리학회지

BACKGROUND: HLA-B27 typing has long been performed by the microlymphocytotoxicity method(MCT) but the flow cytometry method(FCM) was introduced several years ago. False positive results due to the HLA-B7 cross reactive groups(CREG) were the main drawback of the serologic method. The authors performed polymerase chain reaction-sequence specific primer(PCR-SSP) test for HLA-B27 to compare the results with serologic methods. METHODS: PCR-SSP test for HLA-B27 was performed on four hundred forty one samples. Three hundred twenty eight samples were tested by MCT and one hundred thirteen samples by FCM. PCR-SSP for HLA-B27 subtyping or Amplification Refractory Mutation System-PCR(ARMS-PCR) for HLA-B typing was performed on twenty four discrepant samples. RESULTS: The concordance rate between MCT and PCR-SSP was 92.9%(305/328) and the concordance rate between FCM and PCR-SSP was 99.1%(112/113). Twenty four(5.4%) out of four hundred forty one samples showed discrepancy between serologic methods and PCR-SSP method. Fourteen out of one hundred MCT positive samples and only one out of forty FCM positive samples showed negative by PCR-SSP. Nine samples showed PCR-SSP positive and MCT negative. CONCLUSIONS: The false positive rate of MCT was quite high and there were some false positive and negative results by PCR-SSP, too. From the above findings, we suggest that FCM is the most accurate method for HLA-B27 typing in those laboratory equipped with flow cytometry.