Predictors of hookworm and Opisthorchis viverrini infection among adolescents in urban Laos: a cross-sectional study.

Purpose: Infection with hookworm and Opisthorchis viverrini are serious health problems among children and adolescents in Laos. In this study, we demonstrated the factors related to hookworm and O. viverrini infection, including primary school health programs, among secondary school students in Vientiane city of Laos. Material and methods: A cross-sectional survey and stool examination were conducted among secondary school students in Vientiane. One stool sample from each participant was examined using two Kato-Katz smears. Data of 164 participants were analyzed and the associations among parasitic infections, sociodemographic characteristics, and the school health program in primary school were assessed in a univariate logistic regression analysis. Predictors with p<0.25 were retained in a multivariate logistic regression model. Odds ratios (ORs) and 95% confidence intervals (CIs) were reported. The significance level was set at p<0.05. Results: The infection rates of O. viverrini and hookworm were 39.0% and 36.0%, respectively. Older students (OR=1.55, 95% CI: 1.01-2.37, p=0.046) and those whose father had irregular income (OR=0.47, 95% CI: 0.13-0.93, p=0.036) had a higher risk for hookworm infection. Students whose mother had irregular income (OR=0.30, 95% CI: 0.13-0.69, p=0.005) had a higher risk for O. viverrini infection. Higher primary school health program scores were associated with a lower risk for hookworm infection in the univariate model but not in the multivariate model. Conclusion: Sociodemographic factors have a strong influence on infections with both hookworm and O. viverrini. Current school health programs in Laos may be insufficient to reduce O. viverrini infections. Other approaches, such as supporting parents in finding employment with regular income, may be needed.

The transcriptional mediator subunit MED1/TRAP220 in stromal cells is involved in hematopoietic stem/progenitor cell support through osteopontin expression.

MED1/TRAP220, a subunit of the transcriptional Mediator/TRAP complex, is crucial for various biological events through its interaction with distinct activators, such as nuclear receptors and GATA family activators. In hematopoiesis, MED1 plays a pivotal role in optimal nuclear receptor-mediated myelomonopoiesis and GATA-1-induced erythropoiesis. In this study, we present evidence that MED1 in stromal cells is involved in supporting hematopoietic stem and/or progenitor cells (HSPCs) through osteopontin (OPN) expression. We found that the proliferation of bone marrow (BM) cells cocultured with MED1 knockout (Med1(-/-)) mouse embryonic fibroblasts (MEFs) was significantly suppressed compared to the control. Furthermore, the number of long-term culture-initiating cells (LTC-ICs) was attenuated for BM cells cocultured with Med1(-/-) MEFs. The vitamin D receptor (VDR)- and Runx2-mediated expression of OPN, as well as Mediator recruitment to the Opn promoter, was specifically attenuated in the Med1(-/-) MEFs. Addition of OPN to these MEFs restored the growth of cocultured BM cells and the number of LTC-ICs, both of which were attenuated by the addition of the anti-OPN antibody to Med1(+/+) MEFs and to BM stromal cells. Consequently, MED1 in niche appears to play an important role in supporting HSPCs by upregulating VDR- and Runx2-mediated transcription on the Opn promoter.

Differential expression of proteinase inhibitor-9 and granzyme B mRNAs in activated immunocompetent cells.

The role of proteinase inhibitor (PI)-9 in hematopoietic cells remains unclear. To clarify the role of PI-9 in these cells, we compared the expressions of PI-9 mRNA and antigen with those of granzyme B (GrB). While the strongest expression of PI-9 mRNA was observed in a NK cell line YT-N10, it was also expressed in a B-acute lymphoblastic leukemia cell line U-Tree02, an Epstein-Barr Virus (EBV)-transformed B cell clone, a CD8+ T lymphocyte clone and a megakaryocytic cell line CMK, but not in a T cell line Jurkat. Phorbol 12-myristate 13 acetate (PMA) enhanced PI-9 mRNA expression in the CD8+ T lymphocyte clone and YT-N10 cells prior to GrB mRNA expression. IL-2 and IL-12 also had similar effects. PMA increased PI-9 mRNA expression in the EBV-transformed B cell clone and CMK cells, but IL-6 showed no effect. No changes were noted in PI-9 and GrB antigens after the addition of these agonists. Patients with graft-versus-host disease (GVHD) may have activated CTLs and NK cells. We therefore examined the expression of PI-9 and GrB mRNAs in eight patients after allogeneic hematopoietic stem cell transplantation with GVHD (n = 4) or without chronic GVHD (n = 4). Expression of GrB mRNA was significantly increased in three patients with GVHD and one patient without GVHD. Surprisingly, PI-9 mRNA expression was decreased in the eight patients. These results indicate that earlier synthesis of PI-9 may be essential for the prevention of autolysis of immunocompetent cells, and that the expression of PI-9 and GrB mRNAs may be controlled through different pathways.

[Harvesting of autologous peripheral blood stem cells following percutaneous isolated hepatic perfusion for patients with advanced hepatocellular carcinoma].

Percutaneous isolated hepatic perfusion (PIHP) using high-dose chemotherapeutic agents is highly effective for advanced hepatocellular carcinoma in comparison with conventional regional and systemic chemotherapies. However, bone marrow toxicities resulting from the first PIHP preclude additional second/third PIHP in some cases. In an attempt to increase safety of repeated PIHP, autologous peripheral blood stem cells (PBSC) were harvested after the first PIHP in nine patients with multiple hepatocellular carcinoma with administration of G-CSF. PBSCs were successfully harvested in only three patients with relatively well-preserved liver function, whereas PBSC harvests were unsatisfactory in the remaining six patients with highly impaired liver function. The possible reasons for this phenomenon may include hypofunction of bone marrow in cirrhotic patients, and an insufficient use of G-CSF in the present study. Alfa-fetoprotein-mRNA, determined by nested RT-PCR, was detected in six PBSCs, indicating frequent contamination of tumor cells. More precise studies are needed before clinical application of autologous stem cell infusion for patients with malignant hepatic tumors and impaired liver function.

[Levels of granzyme B, perforin and Fas ligand antigens and mRNAs in patients following allogeneic hematopoietic stem cell transplantation].

In order to monitor the immunological status of patients after allogeneic hematopoietic stem cell transplantation(HSCT), granzyme B(GrB), perforin(PRF) and Fas ligand(L) antigens and mRNAs were measured by flow cytometry and real time RT-PCR, respectively. Cytoplasmic antigens were detected in whole blood after fixation and pretreatment with saponin. Real time PCR was carried out using extracted RNA from buffy coat. We measured these substances in a cytotoxic T cell clone, a natural killer cell line, and peripheral blood collected from 11 patients after HSCT. Although changes in antigen levels were not detected, increased levels of GrB and Fas L mRNAs were quantitatively measured in CTLs and NK cells stimulated by IL-2 combined with IL-12. Increased levels of GrB and/or PRF antigens were detected in four of five patients with chronic GVHD. Increased mRNA levels were also observed in one or more of GrB, PRF or Fas L in four of five patients with cGVHD, although there was a discrepancy between antigen and mRNA positivity. Four of six patients without cGVHD were positive for apoptosis-inducing factors, either by antigen detection or RT-PCR. One of these four had relapsing leukemia, and another had herpes zoster infection, while the reasons for positive results in the other two patients are not clear. Although changes in antigen levels did not parallel those in mRNA, measurement of these parameters may assist in predicting GVHD, GVL and infections following HSCT.

Inhibition of natural killer cytotoxicity in vitro by clinical grade serine protease inhibitors.

The effects of clinical grade serine protease inhibitors on natural killer (NK) activity were compared. Cytotoxicity was measured with the Calcein-AM release method, using K562, Raji as a target. There is a significant correlation between measurements of NK activity by the Calcein-AM method and the 51Cr release assay. Cytotoxicity was inhibited with a calcium chelating agent or a perform inhibitor. Although up to 65% of cytotoxicity was inhibited by nafamostat mesilate with an E/T ratio of 10:1, and by 55% by ulinastatin, neither gabexate mesilate nor antithrombin III inhibited any cytotoxicity. None of these agents inhibited lymphokine-activated killer cell activity. In clinical applications, it should be noted that some protease inhibitors have been proven to have immunosuppressive effects.

Expression of granulysin mRNA in the human megakaryoblastic leukemia cell line CMK.

Granulysin is a newly reported cytolytic molecule and colocalizes with perforin and granzymes in the granules of cytotoxic T lymphocytes (CTL) and natural killer (NK) cells. In this study, we found that the megakaryoblastic leukemia cell line CMK, established from a patient with Down's syndrome, expressed granulysin mRNA. CMK was positive for CD13 and CD41 and negative for CD56. CMK also expressed CD2 and CD7. However, no rearrangement of the T-cell receptor beta-chain gene, an early marker of T-cell lineage, was found in CMK cells. Thus, CMK is assumed to originate from the clonal evolution at the immature cell level. The expression of granulysin in CMK cells suggests that granulysin is occasionally present in immature multilineage cells or may be characteristic of leukemic cells obtained from Down's syndrome patients. CMK has been reported to be capable of differentiating to mature megakaryocytes and produce platelets with normal function. It therefore seems to be possible that granulysin is also present in normal platelets. Unfortunately, we were not able to obtain evidence that normal platelets contain granulysin mRNA and its antigen.