Natural regulatory T cells increase significantly in pediatric patients with parasitic infections: Flow cytometry study.

Background: The most accepted definition of regulatory T cells (Tregs) relies on the expression of several biomarkers, including CD4, CD25, and transcription factor, Foxp3. The Tregs maintain tolerance to self-antigens and prevent autoimmune diseases. Aim: The purpose of this study was to determine the difference in natural Treg levels in Entamoeba histolytica, Schistosoma mansoni, Giardia lamblia, Enterobius vermicularis, and Hymenolepis nana infected patients. Setting and Design: Fifty-one pediatric subjects (29 males and 22 females) were recruited from a tertiary care hospital, and were divided into infected and non-infected (control) groups. The mean age of the subjects was 8.7 years. Materials and Methods: Blood samples were collected from infected and non-infected groups, and change in the level of Tregs in these subjects was investigated by flow cytometry. Statistical Analysis Used: The statistical analysis of data was performed by SPSS software. Quantitative data used in this study included mean and standard deviation. Data from the two groups were compared by the Student's t-test. The age of the patient and infection status were used for multivariate logistic regression analysis. Odds ratios (ORs) were estimated within a 95% confidence interval, and a P value of <0.05 was considered significant. Results and Conclusions: The levels of natural regulatory T cells, indicated by the biomarkers, CD4+, CD25+, and Foxp3+, increase significantly in patients infected by Entamoeba histolytica, Schistosoma mansoni, Giardia lamblia, Enterobius vermicularis, and Hymenolepis nana as compared to controls. They also increase in cases of mixed infection as compared to infection by a single parasite.

Hybrid capture-II and LCR-E7 PCR assays for HPV typing in cervical cytologic samples.

As part of an ongoing cohort study in the Hokuriku region of Japan, cervical cell samples from histologically confirmed normal (n = 114) or abnormal (n = 286) women were examined for the presence of HPV DNA using a second-generation hybrid capture assay (HCA-II) and LCR-E7 PCR. HCA-II detected low-risk (HPV-6, -11, -42, 43 and -44) and high-risk (HPV-16, -18, -31, -33, -35, -39, -45, -51, -52, -56, -58, -59 and -68) HPV types, while LCR-E7 PCR detected an additional 7 HPV types and some uncharacterized types. In screening of high-grade squamous intraepithelial lesions (HSILs) and invasive cervical cancer, the sensitivities of HCA-II and LCR-E7 PCR testing the high-risk HPV types were 83% and 81%, respectively, while the specificity of both assays was 93%. The sensitivity of LCR-E7 PCR increased to 87%, which was significantly higher than that in HCA-II, when testing both high-risk and other HPV types. Sixty-eight inconsistent results (17% of total tested) from HCA-II and LCR-E7 PCR were due to (i) low copy number of HPV genome (false-negative for HCA-II, 5.3% and for LCR-E7 PCR, 1.3%), (ii) infection with HPV types undetectable by HCA-II (4.8%), (iii) multiple HPV infections (5%) or (iv) unknown reasons (0.8%). LCR-E7 PCR revealed that infections with HPV-16, -18, -31, -33, -35, -51, -52, -56, -58 or -67 was a high risk for cancer since these types predominated in HSIL and invasive cervical cancer. Samples showing high relative light units (>20) with a high-risk probe in HCA-II also gave positive results in LCR-E7 PCR and were generally associated with abnormal cervical lesions. Thus, we propose that both HCA-II and LCR-E7 PCR are valuable screening tests for premalignant and malignant cervical lesions.

High-risk and multiple human papillomavirus infections associated with cervical abnormalities in Japanese women.

To estimate the risk of human papillomavirus (HPV) infection for cervical malignancies, we conducted a case-control study in Japan. Abnormal cervical cell (366) and normal cell samples (1562) were tested for the presence of HPV DNA using a new PCR-based test (LCR-E7 PCR). When single HPV infections were considered, 26 different HPV types were identified in normal cervices and in low-grade squamous intraepithelial lesions (LSIL); whereas HPV-16, -18, -31, -33, -35, -45, -51, -52, -56, -58 and -67 were detected in high-grade squamous intraepithelial lesions (HSIL) and in squamous cell carcinoma (SCC) of the cervix, and HPV-16 and -18 were detected in cervical adenocarcinoma. HPV-6 and -11 were detected in condyloma acuminatum tissue. In HSIL and SCC, HPV-16 was the most prevalent type and HPV-51, -52, and -58 were the next most prevalent; whereas HPV-39, -59, and -68 were not detected. Analysis by odds ratio (OR) revealed that HPV-11, -39, -42, -44, -53, -59, -62, and -66 (HPV-66: OR,139; 95% confidence interval (CI) = 6.7-168) were associated with LSIL; HPV-16, -18, -31, -51, -52 and -58 (HPV-16: OR, 69; 95%CI = 36-131) were associated with SCC; and HPV-16 and -18 (OR, 94; 95% CI = 28-317) were associated with adenocarcinoma. Multiple HPV infection was associated with LSIL (OR, 24; 95%CI = 13-44), HSIL (OR, 16; 95%CI = 8.4-32), and SCC (OR, 8.3; 95%CI = 3.2-22), although the prevalence decreased with the grade of the lesions. All results suggest that HPV-6 and -11 are condyloma types, HPV-16, -18, -31, -51, -52, -58, and perhaps -33, -35, -45, -56, and -67, are the high-risk HPV types, and many other types are LSIL-associated types in Japan. HPV typing and detection of multiple HPV infections in clinical samples may be useful as surrogate markers for cervical cell abnormalities.

A new PCR-based assay amplifies the E6-E7 genes of most mucosal human papillomaviruses (HPV).

We established a new assay to detect the E6-E7 DNA of mucosal human papillomaviruses (HPV) by a PCR-based method using four pairs of degenerate LCR and E7 primers (LCR-E7 PCR). This assay amplifies the full length of E6 and the N-terminal part of E7. HPV typing was performed using restriction-fragment-length polymorphism (RFLP), and by analyzing the sequences of cloned PCR products. We compared this assay with the first generation hybrid captured assay (HCA-I) and the MY09/11-PCR method. LCR-E7 PCR was able to detect more than 34 mucosal HPV types and theoretically should detect two additional types. LCR-157 PCR and HCA-I detected HPV DNA in 70% (69/99) and 55% (54/99) of low-grade cervical intraepithelial lesions (LSIL), 89% (105/118) and 76% (90/118) of high-grade cervical intraepithelial lesions (HSIL), and 90% (56/62) and 79% (49/62) of invasive squamous cell carcinomas (SCC), respectively. LCR-E7 PCR was more sensitive than the HCA-1 test. Discordant results between the LCR-E7 and MY 11/09-PCR tests were observed in one of 185 (0.5%) normal samples, seven of 85 (8.2%) LSIL samples, seven of 82 (8.5%) HSIL samples, and four of 72 (5.6%) SCC samples. The discordant results were mostly observed in samples with a low-copy number of the HPV genome or with multiple HPV infection. The sensitivity of LCR-E7 PCR was equivalent to that of MY 11/09 ECR, and false positives were less frequent in LCR-E7 PCR. LCR-E7 PCR may be useful for determining the biological activity of detected HPV types, since this method amplifies the entire E6 gene.