Exercise training reduces the risk of opportunistic infections after acute exercise and improves cytokine antigen recognition.

In general, acute exercise is thought to inhibit immune function and increase the risk of opportunistic infections, but there is some opposition to this due to a lack of quantitative evaluation. Therefore, we quantified the effect of exercise on immune function and observed the interaction between antigens and cytokines using an intramuscular infection with Trichinella spiralis (T. spiralis), a common parasitic infection model. C57BL/6 mice were used for a non-infection experiment and an infection (Inf) experiment. Each experiment was divided further into three groups: one control (CON) group, and an exercise pre-infection (PIE)-only group and exercise-sustained (ES) group, each of which was subjected to exercise for 7 weeks. All animals in the infection experiment were infected with T. spiralis 30 min after acute exercise. After infection, the ES and Inf-ES groups continued exercise for 7 additional weeks. The number of T. spiralis nurse cells remaining in skeletal muscles was fewer in the infected exercise groups compared with the infected control. Expression of interleukin-6 (IL-6) and interleukin-10 (IL-10) was higher in the Inf-CON group and transforming growth factor beta (TGF-ß) expression was lower in the Inf-CON group than in the CON group, as measured by RT-PCR. In the infection experiment, only IL-10 had significant differences between the groups. Immunofluorescence revealed that most cytokines were specifically expressed around the antigenic nurse cells following exercise. In conclusion, exercise training does not increase the risk of opportunistic infections even after acute exercise, but rather reduces it. These results may be due to antigen-specific immune responses.

Induction of Angiogenesis by Malarial Infection through Hypoxia Dependent Manner.

Malarial infection induces tissue hypoxia in the host through destruction of red blood cells. Tissue hypoxia in malarial infection may increase the activity of HIF1α through an intracellular oxygen-sensing pathway. Activation of HIF1α may also induce vascular endothelial growth factor (VEGF) to trigger angiogenesis. To investigate whether malarial infection actually generates hypoxia-induced angiogenesis, we analyzed severity of hypoxia, the expression of hypoxia-related angiogenic factors, and numbers of blood vessels in various tissues infected with Plasmodium berghei. Infection in mice was performed by intraperitoneal injection of 2×106 parasitized red blood cells. After infection, we studied parasitemia and survival. We analyzed hypoxia, numbers of blood vessels, and expression of hypoxia-related angiogenic factors including VEGF and HIF1α. We used Western blot, immunofluorescence, and immunohistochemistry to analyze various tissues from Plasmodium berghei-infected mice. In malaria-infected mice, parasitemia was increased over the duration of infection and directly associated with mortality rate. Expression of VEGF and HIF1α increased with the parasitemia in various tissues. Additionally, numbers of blood vessels significantly increased in each tissue type of the malaria-infected group compared to the uninfected control group. These results suggest that malarial infection in mice activates hypoxia-induced angiogenesis by stimulation of HIF1α and VEGF in various tissues.

Effect of Muscle Strength by Trichinella spiralis Infection during Chronic Phase.

Introduction:Trichinella spiralis establishes a chronic infection in skeletal muscle by developing nurse cells within muscle fibers. During symbiosis in host, changes in the muscle fibers and inflammation may affect muscle function. Methods: We investigated muscle strength and inflammation in T. spiralis-infected mice during 1 to 48 weeks after infection. Results: Muscle strength decreased compared to that in uninfected control mice during the late infection stage. Additionally, inflammatory related cytokines increased significantly during early stage of infection and then rapidly decreased. In pathological study, nuclear infiltration maintained from the early infection stage to chronic infection stage. Moreover, vacuoles and eosinophil infiltration were observed in infected muscle in chronic stage. Conclusion: These results suggest that infection by T. spiralis significantly affects muscle function was continuously being weakness because vacuoles formation and maintained nucleus and eosinophil infiltration during chronic phase of T. spiralis infection.

DDX4 (DEAD box polypeptide 4) colocalizes with cancer stem cell marker CD133 in ovarian cancers.

DDX4 (DEAD box polypeptide 4), characterized by the conserved motif Asp-Glu-Ala-Asp (DEAD), is an RNA helicase which is implicated in various cellular processes involving the alteration of RNA secondary structure, such as translation initiation, nuclear and mitochondrial splicing, and ribosome and spliceosome assembly. DDX4 is known to be a germ cell-specific protein and is used as a sorting marker of germline stem cells for the production of oocytes. A recent report about DDX4 in ovarian cancer showed that DDX4 is overexpressed in epithelial ovarian cancer and disrupts a DNA damage-induced G2 checkpoint. We investigated the relationship between DDX4 and ovarian cancer stem cells by analyzing the expression patterns of DDX4 and the cancer stem cell marker CD133 in ovarian cancers via tissue microarray. Both DDX4 and CD133 were significantly increased in ovarian cancer compared to benign tumors, and showed similar patterns of expression. In addition, DDX4 and CD133 were mostly colocalized in various types of ovarian cancer tissues. Furthermore, almost all CD133 positive ovarian cancer cells also express DDX4 whereas CD133-negative cells did not possess DDX4, suggesting a strong possibility that DDX4 plays an important role in cancer stem cells, and/or can be used as an ovarian cancer stem cell marker.

Thymosin ß4 induces the expression of vascular endothelial growth factor (VEGF) in a hypoxia-inducible factor (HIF)-1α-dependent manner.

Thymosin ß4 has multi-functional roles in cell physiology, but little is known about its mechanism(s) of action. We previously reported that thymosin ß4 stimulated angiogenesis through the induction of vascular endothelial growth factor (VEGF). To identify the mechanism of VEGF induction by thymosin ß4, we have used a luciferase assay system with VEGF in the 5' promoter region. We also analyzed the effect of thymosin ß4 on VEGF mRNA stability and on the expression and stability of hypoxia-inducible factor (HIF)-1α. We found that thymosin ß4 induces VEGF expression by an increase in the stability of HIF-1α protein. Analysis of the expression patterns of thymosin ß4 and HIF-1α in colon cancer tissue microarray showed that thymosin ß4 and HIF-1α co-localized in these biopsies. These data show that thymosin ß4 induces the expression of VEGF indirectly by increasing the protein stability of HIF-1α.

Anisakis simplex larvae: infection status in marine fish and cephalopods purchased from the Cooperative Fish Market in Busan, Korea.

The infection status of marine fish and cephalopods with Anisakis simplex third stage larva (L3) was studied over a period of 1 year. A total of 2,537 specimens, which consisted of 40 species of fish and 3 species of cephalopods, were purchased from the Cooperative Fish Market in Busan, Korea, from August 2006 to July 2007. They were examined for A. simplex L3 from the whole body cavity, viscera, and muscles. A. simplex L3 were confirmed by light microscopy. The overall infection rate reached 34.3%, and average 17.1 larvae were parasitized per infected fish. Fish that recorded the highest infection rate was Lophiomus setigerus (100%), followed by Liparis tessellates (90%), Pleurogrammus azonus (90%), and Scomber japonicus (88.7%). The intensity of infection was the highest in Gadus macrocephalus (117.7 larvae per fish), followed by S. japonicus (103.9 larvae) and L. setigerus (54.2 larvae). Although abundance of A. simplex L3 was not seasonal in most of the fish species, 10 of the 16 selected species showed the highest abundance in February and April. A positive correlation between the intensity of L3 infection and the fish length was obvious in S. japonicus and G. macrocephalus. It was likely that A. simplex L3 are more frequently infected during the spring season in some species of fish. Our study revealed that eating raw or undercooked fish or cephalopods could still be a source of human infection with A. simplex L3 in Korea.

Seroprevalence of antibodies against Anisakis simplex larvae among health-examined residents in three hospitals of southern parts of Korea.

The present study was performed to estimate the seroprevalence of larval Anisakis simplex infection among the residents health-examined in 3 hospitals in southern parts of Korea. A total of 498 serum samples (1 serum per person) were collected in 3 hospitals in Busan Metropolitan city, Masan city, and Geoje city in Gyeongsangnam-do (Province) and were examined by IgE-ELISA and IgE-western blotting with larval A. simplex crude extract and excretory-secretory products (ESP). The prevalence of antibody positivity was 5.0% and 6.6% with ELISA against crude extracts and ESP, respectively. It was also revealed that infection occurred throughout all age groups and higher in females than in males. A specific protein band of 130 kDa was detected from 10 patients with western blot analysis against crude extract and ESP among those who showed positive results by ELISA. Our study showed for the first time the seroprevalence of anisakiasis in Korea. The allergen of 130 kDa can be a candidate for serologic diagnosis of anisakiasis.

Over-expression of thymosin ß4 in granulomatous lung tissue with active pulmonary tuberculosis.

Recent studies have shown that thymosin ß4 (Tß4) stimulates angiogenesis by inducing vascular endothelial growth factor (VEGF) expression and stabilizing hypoxia inducible factor-1α (HIF-1α) protein. Pulmonary tuberculosis (TB), a type of granulomatous disease, is accompanied by intense angiogenesis and VEGF levels have been reported to be elevated in serum or tissue inflamed by pulmonary tuberculosis. We investigated the expression of Tß4 in granulomatous lung tissues at various stages of active pulmonary tuberculosis, and we also examined the expression patterns of VEGF and HIF-1α to compare their Tß4 expression patterns in patients' tissues and in the tissue microarray of TB patients. Tß4 was highly expressed in both granulomas and surrounding lymphocytes in nascent granulomatous lung tissue, but was expressed only surrounding tissues of necrotic or caseous necrotic regions. The expression pattern of HIF-1α was similar to that of Tß4. VEGF was expressed in both granulomas and blood vessels surrounding granulomas. The expression pattern of VEGF co-localized with CD31 (platelet endothelial cell adhesion molecule, PECAM-1), a blood endothelial cell marker, and partially co-localized with Tß4. However, the expression of Tß4 did not co-localize with alveolar macrophages. Stained alveolar macrophages were present surrounding regions of granuloma highly expressing Tß4. We also analyzed mRNA expression in the sputum of 10 normal and 19 pulmonary TB patients. Expression of Tß4 was significantly higher in patients with pulmonary tuberculosis than in normal controls. These data suggest that Tß4 is highly expressed in granulomatous lung tissue with active pulmonary TB and is associated with HIF-1α- and VEGF-mediated inflammation and angiogenesis. Furthermore, the expression of Tß4 in the sputum of pulmonary tuberculosis patients can be used as a potential marker for diagnosis.

Trichinella spiralis infection reduces tumor growth and metastasis of B16-F10 melanoma cells.

Recently, attempts have been made to use parasites as novel candidates for live vaccine vectors against solid tumors. In this study, we examined the effects of Trichinella spiralis (T. spiralis) infection on solid tumor growth and metastasis. After oral infection with T. spiralis larvae, B16-F10 cells were injected subcutaneously and intravenously into C57BL/6 mice to evaluate tumor growth and metastatic potential, respectively. Tumor growth and lung metastases in T. spiralis infected mice were significantly reduced compared with control mice. To elucidate the mechanism of tumor reduction by parasitic infection, we conducted cytokine arrays using mouse serum. CXCL9 and CXCL10 were increased in the infection group and decreased in the infection-tumor group. However, the expression level was not changed in the infection-metastasis group compared to the infection or control-metastasis groups. Although SDF-1 and IL-4 were increased in the infection group, there was no significant change in expression in the infection-tumor group or the infection-metastasis group. Additionally, IL-4 and KC were increased in the infection-tumor group compared to the control-tumor group, but there was no difference in expression between the control-metastasis group and the infection-metastasis group. CXCL13 was significantly increased in the infection-metastasis group only. These results suggest that T. spiralis infection reduced tumor growth and metastasis through a complex transition in cytokine regulation profiles including CXCL9, CXCL10, and CXCL13.

Expression patterns of Thymosin ß4 and cancer stem cell marker CD133 in ovarian cancers.

Thymosin ß4 (Tß4), a small acidic actin binding peptide, is overexpressed in a side population of cancer stem cells and CD133-positive colorectal cancer stem cells. In order to understand the relationship between Tß4 and CD133, we studied the expression patterns of Tß4 and CD133 in ovarian cancers. The expression patterns of Tß4 and CD133 were studied in normal ovaries, primary ovarian cancers, metastatic ovarian cancers, primary stomach cancers, and normal stomachs by Western blot and immunohistochemistry. Expression patterns and co-localization of Tß4 and CD133 were examined by immunofluorescence and confocal laser-scanning microscopy. Tß4 is overexpressed in primary ovarian cancers, but not in primary stomach cancers, when compared with normal controls. However, Tß4 levels in metastatic stomach cancers to the ovary are significantly upregulated compared with levels in normal stomachs and primary stomach cancers. These results suggest that Tß4 levels are related to tumorigenesis in ovarian cancers and metastasis in stomach cancers. The expression of Tß4 in normal ovaries and normal stomachs was weak, but was co-localized with CD133 expression. Tß4 expression was also co-localized with CD133 expression in primary ovarian carcinomas, metastatic ovarian cancers from stomach cancers and primary stomach cancers. These data suggest that Tß4 expression is strongly related to CD133 expression and is a characteristic of stem cells or cancer stem cells.

Trichinella spiralis infection induces ß-actin co-localized with thymosin ß4.

Trichinella spiralis (T. spiralis) infection in muscle is characterized by the vascular network for the nurse cell-larva complex. We showed in a previous report that thymosin ß4 was up-regulated during nurse cell formation by T. spiralis. As thymosin ß4 (Tß4) is the actin-sequestering protein that regulates actin polymerization, the expression pattern of ß-actin during the nurse cell formation was analyzed. The protein level of ß-actin in muscle fibers 10 days after infection was significantly increased, and its expression remained high in the nurse cells for six weeks. In order to investigate the functional relationship between Tß4 and ß-actin, localization of two proteins was analyzed. Immunofluorescence showed that Tß4 and ß-actin were co-localized in the T. spiralis-infected nurse cells from 10 days to six weeks. The expression patterns of other actin-binding proteins, including thymosin ß10 (Tß10), subunits of the Arp2/3 complex, subunits of Capping protein, profilin, and cofilin, were also analyzed at the mRNA level. Tß10 expression was also increased during nurse cell formation. Expressions of the Arp2/3 complex was increased at 21 days after infection and Capping proteins was increased during nurse cell formation but shows different expression patterns, depending on the subunit. Profilin and cofilin were specifically increased in the muscle fibers from 14 days after infection. These data show that Tß4 and ß-actin are over-expressed during nurse cell formation upon T. spiralis infection and may be involved in nurse cell formation along with other actin-binding proteins.

Trichinella spiralis infection induces angiogenic factor thymosin ß4 expression.

Trichinella spiralis (T. spiralis) has been reported to up-regulate the expression of the angiogenic molecule vascular endothelial cell growth factor (VEGF) during nurse cell formation. In order to analyze the induction of angiogenesis by T. spiralis, the expression patterns of angiogenesis-related proteins were investigated by immunohistochemical analysis. VEGF expression was induced in the infected muscles at an early stage of infection (10 days after infection) and diminished after 3 weeks. Thymosin ß4, a major factor which induces VEGF, showed increased expression in muscle fibers 10 days after infection, and the expression remained high in the nurse cells for 6 weeks, when the formation of the nurse cell complex was completed. The hypoxia inducible factor (HIF)-1α showed a diffuse expression pattern around the infected muscle fibers and was strongly expressed in inflammatory cells but was not related to the hypoxic condition caused by nurse cell formation. Localization of the hypoxic regions by the hypoxia marker, pimonidazole showed T. spiralis infection does not induce a hypoxic condition in nurse cells. These results suggest that the expression of VEGF and thymosin ß4 induce angiogenesis and the expression of thymosin ß4 remained elevated to potentially regulate nurse cell formation and maintenance.

Thymosin ß4 expression in human tissues and in tumors using tissue microarrays.

Thymosin ß4 has been reported to play the key roles in tumor growth, metastasis, and angiogenesis. Although the importance of thymosin ß4 in angiogenesis and metastasis is known, few studies to show the expression patterns of thymosin ß4 in human tissues including tumors have been conducted. The comparisons of the expression of thymosin ß4 between the normal and tumor tissues are also needed to study the role of thymosin ß4 in tumor formation. Using tissue microarray analysis, we compared the expression patterns of thymosin ß4 in the normal human tissues and in the tumors to screen certain tumors and upregulated the expression of thymosin ß4 by tumorigenesis. Thymosin ß4 was highly expressed in the hepatic cells in the normal adult liver, duct, and acinar cells in pancreas, and muscle cells in the heart and also expressed highly in certain tumor cells, including osteosarcoma, colon adenocarcinoma, esophageal squamous cell carcinoma, kidney and urinary bladder transitional carcinoma, lung cancer, and liver cancer. Comparing the thymosin ß4 expression between normal and tumors, thymosin ß4 was upregulated specifically in osteosarcoma, colorectal carcinoma, and esophageal cancer. To confirm the over-expression of thymosin ß4 in these tumors, we analyzed expression of thymosin ß4 with each additional microarray of osteosarcoma, colorectal carcinoma, and esophageal cancer. The significant increased expression of thymosin ß4 was observed in osteosarcoma and in colorectal cancer. These results suggest that the expression of thymosin ß4 is highly related with tumorigenesis of certain tumors including the osteosarcoma and colorectal cancers.

Elevated expression of thymosin ß4, vascular endothelial growth factor (VEGF), and hypoxia inducible factor (HIF)-1α in early-stage cervical cancers.

Recent studies have shown that thymosin ß4 (TB-4) is highly related with tumor metastasis and angiogenesis. In addition, TB-4 induced the expression of VEGF in melanoma cells. We investigated the expression patterns of TB-4 and related angiogenic proteins, VEGF, and HIF-1α, at various stages of cervical cancers and also identified the expression pattern of these proteins in metastatic cervical cancers. Expression patterns of TB-4, VEGF, and HIF-1α were studied with tissue microarray containing 42 samples of cervical cancers. In addition, 15 cervical cancers and metastatic tumors in lymph nodes from patients who have metastatic tumors were also analyzed to confirm the role of TB-4, VEGF, and HIF -1α in cervical cancer metastasis. The expression levels of TB-4, VEGF, and HIF-1α were very weak at early cancer stages (stages 0 to 1A) but significantly increased at stage 1B. The numbers of blood vessels in tumors were also increased at stage 1B. The expression patterns of TB-4, VEGF, and HIF-1α were compared in tumors without lymph node metastasis, primary tumors with lymph node metastasis, and metastatic tumors in lymph nodes. The expression levels of TB-4, VEGF, and HIF-1α in primary tumors with lymph node metastasis and their metastatic tumors in lymph node were less than in tumors without lymph node metastasis. These data suggest that TB-4, VEGF, and HIF-1α triggered angiogensis and tumor invasiveness to surrounding tissues at early stage of cervical carcinoma but have a negative or no effect on the metastatic potential.