Inside-the-body light delivery system using endovascular therapy-based light illumination technology.

BACKGROUND: Light-based therapies are promising for treating diseases including cancer, hereditary conditions, and protein-related disorders. However, systems, methods, and devices that deliver light deep inside the body are limited. This study aimed to develop an endovascular therapy-based light illumination technology (ET-BLIT), capable of providing deep light irradiation within the body. METHODS: The ET-BLIT system consists of a catheter with a single lumen as a guidewire and diffuser, with a transparent section at the distal end for thermocouple head attachment. The optical light diffuser alters the emission direction laterally, according to the optical fibre's nose-shape angle. If necessary, after delivering the catheter to the target position in the vessel, the diffuser is inserted into the catheter and placed in the transparent section in the direction of the target lesion. FINDINGS: ET-BLIT was tested in an animal model. The 690-nm near-infrared (NIR) light penetrated the walls of blood vessels to reach the liver and kidneys without causing temperature increase, vessel damage, or blood component alterations. NIR light transmittance from the diffuser to the detector within the organ or vessel was approximately 30% and 65% for the renal and hepatic arteries, respectively. INTERPRETATION: ET-BLIT can be potentially used in clinical photo-based medicine, as a far-out technology. ET-BLIT uses a familiar method that can access the whole body, as the basic procedure is comparable to that of endovascular therapy in terms of sequence and technique. Therefore, the use of the ET-BLIT system is promising for many light-based therapies that are currently in the research phase. FUNDING: Supported by Programme for Developing Next-generation Researchers (Japan Science and Technology Agency); JSPS KAKENHI (18K15923, 21K07217); JST-CREST (JPMJCR19H2); JST-FOREST-Souhatsu (JPMJFR2017); The Uehara Memorial Foundation; Yasuda Memorial Medical Foundation; Mochida Memorial Foundation for Medical and Pharmaceutical Research; Takeda Science Foundation; The Japan Health Foundation; Takahashi Industrial and Economic Research Foundation; AICHI Health Promotion Foundation; and Princess Takamatsu Cancer Research Fund.

Expression of NCAM in activated portal fibroblasts during regeneration of the rat liver after partial hepatectomy.

In the portal tract of the regenerating liver after partial hepatectomy, vascular and bile ductular remodeling takes place in response to the portal hyperdynamic state and parenchymal hyperplasia. In order to reveal phenotypical changes in the portal fibroblasts, we immunohistochemically investigated neural cell adhesion molecules (NCAM) and alpha smooth muscle actin (alphaSMA) expression and the ultrastructural changes in them during liver regeneration. In the control rat liver, portal fibroblasts were negative for both NCAM and alphaSMA. They became positive for both markers two days after partial hepatectomy, increased in staining intensity, reached a maximum at three to four days, then decreased, being still clearly positive at 14 days. Under an electron microscope, portal fibroblasts from the regenerating liver had larger amounts of cytoplasm and rough endoplasmic reticulum than those from the control liver; thus they might be activated. Additionally, periportal hepatic stellate cells in the regenerating liver were activated with alphaSMA, but without NCAM. The present study has demonstrated that portal fibroblasts express NCAM and alphaSMA in the regenerating liver after partial hepatectomy via transformation into myofibroblasts following reconstruction of the portal tracts.

Macrophage scavenger receptor down-regulates mycobacterial cord factor-induced proinflammatory cytokine production by alveolar and hepatic macrophages.

We aimed to reveal the regulatory function of macrophage scavenger receptor-A (MSR-A) in proinflammatory cytokine production by macrophages stimulated with mycobacterial cord factor (CF). By the culture with CF, MSR-A (+/+) alveolar macrophages and Kupffer cells produced TNF-alpha/MIP-1alpha in a time- and dose-dependent manner. However, the amounts of cytokines produced by them were much less compared to those produced by MSR-A (-/-) macrophages. Consistent with this, treatment of MSR-A (+/+) macrophages with anti-MSR-A antibody increased TNF-alpha production. Binding of CF to MSR-A was demonstrated by measuring the binding affinity. These results indicate that CF binds MSR-A, and MSR-A down-regulates TNF-alpha/MIP-1alpha production by activated macrophages, suggesting the role of this receptor in suppression of excessive inflammatory responses during mycobacterial infection.

TNP-470 blockage of VEGF synthesis is dependent on MAPK/COX-2 signaling pathway in PDGF-BB-activated hepatic stellate cells.

Angiogenesis is a key pathogenic event in hepatic fibrogenesis, which is mediated by activated hepatic stellate cells (HSCs). TNP-470 is a known anti-angiogenic agent in cancer, and in this study, we investigated the regulatory mechanisms of TNP-470 blockage of vascular endothelial growth factor (VEGF) synthesis in activated HSCs. Primary HSCs were isolated from rat liver, cultured in vitro, and activated with platelet-derived growth factor-BB (PDGF-BB). After treatment with TNP-470, Nimesulide, PD98059, SB203580 or SP600125, activated HSCs were analyzed by immunoblotting, quantitative RT-PCR, and ELISA for mitogen-activated protein kinase (MAPK) family [ERKs, JNK, and p38], cyclooxygenase-2 (COX-2), and VEGF levels. Phosphorylation of p44/42 MAPK, which was followed by increased expressions of COX-2 and VEGF, was observed in PDGF-BB-activated HSCs; these events could be ameliorated by addition with TNP-470 in time- and dose-dependent manners. TNP-470 also inhibited the secretion of VEGF from activated HSCs into culture supernatant. Furthermore, TNP-470 blockage of VEGF production in activated HSCs could be nullified by exogenous inoculation with prostaglandin E(2). In summary, our findings suggest that TNP-470 exhibits the observed anti-angiogenic properties in activated HSCs by targeting the COX-2/phospho-p44/42 MAPK pathway to inhibit VEGF production.

Immunohistologic attempt to find carcinogenesis from hepatic progenitor cell in hepatocellular carcinoma.

AIM: To clarify whether hepatocellular carcinoma (HCC) originates from hepatic progenitor cells and whether there is any correlation with the clinicopathologic factors of HCC, we reviewed 217 resected HCC specimens. METHODS: Immunohistochemical examination of cytokeratin (CK) 7, CK19, CD34, and CD117 (c-KIT) was performed. Overexpression of CK7 and CK19 indicates differentiation from cholangiocellular and hepatic progenitor cells, while overexpression of CD34 and CD117 indicates hepatic stem cells. Fresh specimens were obtained from 20 HCC patients for mutation of the c-KIT gene. RESULTS: CK7, CK19, and CD117 were positive in 41, 9.7, and 0.9% of the HCC specimens, respectively, and CD34 was never positive. None of the fresh HCC specimens demonstrated a c-KIT mutation. CK19 positivity was significantly correlated with a positive hepatitis B core antibody, and with poor survival outcome, and tended to correlate with poor histologic differentiation. CONCLUSION: These results suggest that: (i) about 10% of HCCs with typical histologic features originate from an intermediate hepatic progenitor cell, such as the canal of Hering and oval cells in the rat, or acquire the characteristics of cholangiocellular epithelium by metaplasia; (ii) HCC with typical histologic features rarely originates from hepatic stem cells, and (iii) patients with CK19-positive HCC have a poor prognosis.

A murine model of NKT cell-mediated liver injury induced by alpha-galactosylceramide/d-galactosamine.

Natural killer-T (NKT) cells are rich in the liver. However, their involvement in liver injury is not fully understood. We developed here a new murine model of NKT-cell-activation-associated liver injury, and investigated a role of tumor necrosis factor alpha (TNF-alpha) and Fas in pathogenesis. We injected intraperitoneally alpha-galactosylceramide (alpha-GalCer), an NKT-cell stimulant, into D-galactosamine (GalN)-sensitized mice. Survival rate, pathological changes of the liver, and plasma concentrations of cytokines were studied. Alpha-GalCer/GalN administration gave a lethal effect within 7 h, making pathological changes such as massive parenchymal hemorrhage, hepatocyte apoptosis, sinusoidal endothelial cell injury, and close apposition of lymphocytes to apoptotic hepatocytes. Anti-NK1.1 mAb-pretreated mice and Valpha14NKT knock out (KO) mice did not develop liver injury. Tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) were elevated at 4 h in the plasma. These cytokines were produced by hepatic lymphocytes as demonstrated by in vitro stimulation with alpha-GalCer. The lethal effect was suppressed in TNF-alpha KO mice, TNF receptor-1 KO mice, and lpr/lpr (Fas deficient) mice, whereas it was not in IFN-gamma KO mice. These results indicate that the present liver injury is characterized by parenchymal hemorrhage and hepatocyte apoptosis, and mediated by TNF-alpha secretion and direct cytotoxicity of alpha-GalCer-activated NKT cells.

Association of hnRNP S1 proteins with vimentin intermediate filaments in migrating cells.

S1 proteins C2 and D2 are multifunctional hnRNP proteins acting as transcriptional regulators in the nucleus. Immunofluorescence staining of various cells in culture revealed that S1 proteins also occur in the cytoplasm, often in association with vimentin intermediate filaments (VFs). Here, we verified the association of S1 proteins with vimentin using vimentin-deficient cells, crosslinking and immunoprecipitation, and further investigated the biological significance of this association. S1 proteins on VFs, referred to here as S1 fibers, were lost in highly confluent cells, where cell proliferation and cellular metabolic activity greatly decreased owing to cell density-dependent arrest. However, the disappearance of S1 fibers was not related to these reduced activities, but to inhibited cell migration. Although undetected in cells of non-migratory tissues as well as in confluent cultured cells, S1 fibers were found in all migratory cells examined, such as cultured cells in scratch/wound experiments, blood neutrophils and monocytes, and fibroblasts engaging in tissue healing. In addition, S1 fibers reappeared even in confluent cells when VFs were induced to reorganize with okadaic acid. We propose that S1 proteins occur in association with VFs in migratory cells. Possible participation of S1 proteins in the formation/reorganization of VFs is discussed.

Correlation between dynamic computed tomographic and histopathological findings in the diagnosis of small hepatocellular carcinoma.

BACKGROUND/AIMS: To determine the characteristic image findings on dynamic computed tomography (CT) for small hepatocellular carcinoma (HCC), we evaluated the correlation of histopathological and radiological findings with respect to the angioarchitecture in small HCCs. METHODS: CT and early- and late-phase dynamic CT findings of 80 small HCCs (< or =3 cm) were divided into iso-, high, low, and mixed density. We studied the correlation between the imaging findings and the histopathological findings as follows: differentiation grade; presence of fibrous capsule; presence of Glisson's sheath, and growth pattern. RESULTS: High-density early-phase CT and low-density late-phase CT correlated significantly with moderately/poorly differentiated HCCs, which have a fibrous capsule, no Glisson's sheath, and an expansive growth pattern. In contrast, well-differentiated HCCs with a Glisson's sheath and a replacing pattern (early HCC) appeared as iso-dense lesions in the early and late phases. Well-differentiated HCCs (non-early wHCC) demonstrated various density images in the early phase and low-density images in the late phase. CONCLUSIONS: Dynamic CT is an economic and simple diagnostic tool for planning treatment of small HCC lesions because of the multistep nature of HCC carcinogenesis and the hemodynamic changes of tumor blood flow.

Surgical strategy for hepatocellular carcinoma originating in the caudate lobe.

BACKGROUND: The prognosis of hepatocellular carcinoma originating in or mainly involving the caudate lobe (caudate HCC) is generally poor. We reviewed the clinicopathologic findings of patients who underwent liver resection of caudate HCC and correlated the outcome with the surgical strategy. METHODS: Records of 402 patients who underwent liver resection for HCC were reviewed. The patients were divided into 2 groups. One group consisted of 15 patients who underwent liver resection for caudate HCC. The other group included 387 patients with HCC in a site other than the caudate lobe. RESULTS: Anatomic resection of Couinaud segment I or IX (a partial caudate lobectomy), conforming to portal anatomy, was performed in 13 patients with caudate HCC, and segmentectomies of segments I and IX (a total caudate lobectomy) were performed in 2 patients with caudate HCC. The incidence of postoperative complications was similar in the caudate HCC group and HCC in other sites group, with no operative deaths in the caudate HCC group. Tumor-free survival and cumulative survival were similar in the 2 groups. However, among patients with caudate HCC, tumor-free and cumulative survival were lower in patients with than without microscopic portal venous involvement (P<.01). CONCLUSIONS: Partial caudate lobectomy (anatomic resection of segment I or IX) along the portal system is an appropriate procedure for caudate HCC, especially in patients with impaired liver function or a small HCC. Patients with caudate HCC who have microscopic portal venous involvement may require adjuvant therapy as early recurrence is likely.

Regulatory role of vHL/HIF-1alpha in hypoxia-induced VEGF production in hepatic stellate cells.

Activated hepatic stellate cells (HSCs) produce cyclooxygenase-2 (COX-2) protein to induce vascular endothelial growth factor (VEGF) production that participates in angiogenesis in injured liver. To reveal the unknown regulatory mechanism, we used hypoxic atmosphere mimicking injured-tissue microenvironment to induce VEGF expression in a rat hepatic stellate cell line (T6-HSCs). The present study showed that hypoxia up-regulated the protein levels of COX-2 and hypoxia-inducible factor-1-alpha (HIF-1alpha), but rapidly effected degradation of von Hippel-Lindau (vHL) protein. As a result, expression of VEGF in HSCs was markedly elevated; and pretreatment with COX-2 inhibitors (nimesulide or indomethacin) could significantly ameliorate the angiogenic event. Collectively, hypoxic HSCs increased accumulation of HIF-1alpha protein and induced VEGF expression in a time-dependent manner. Inhibition of COX-2 activities would prevent vHL protein from degradation and suppress HIF-1alpha up-regulation. Thus, vHL/HIF-1alpha has a regulatory role in COX-2-mediated VEGF production in hypoxic stellate cells in injured liver.

Pit cells as liver-associated natural killer cells: morphology and function.

Pit cells are one type of hepatic sinusoidal cells, defined morphologically as large granular lymphocytes (LGLs) and functionally as liver-associated natural killer (NK) cells. They are situated inside the sinusoidal lumen, adhering to the endothelial cells and Kupffer cells. They contain multivesicular body-related dense granules and rod-cored vesicles. The number and size of granules and vesicles differ between hepatic NK cells and peripheral blood cells, suggesting possible differentiation of the latter into the former in the microenvironment of the liver. In addition to NK cells, natural killer T (NKT) cells are also abundant in the liver. They share several morphological properties with NK cells, and at least some are probably observed as pit cells under an electron microscope. NK cells recognize target cells with their surface receptors such as inhibitory and activating receptors. They exert antitumor functions by exocytosis of perforin/granzyme-containing granules, induction of death receptor-mediated apoptosis in target cells, and production of various cytokines that augment the activities of other immune cells. NKT cells play important roles in initiating and assisting the function of NK cells by producing interferon-gamma.

Cytokeratin 19 expression in hepatocellular carcinoma predicts early postoperative recurrence.

Clinicopathologic features and postoperative outcomes were investigated for patients who underwent curative surgery for biliary marker (CK7 and CK19)-positive hepatocellular carcinoma (HCC). Of 157 HCCs, 93 were CK7(-)CK19(-), 49 were CK7(+)-CK19(-), 1 was CK7(-)CK19(+), and 14 were CK7(+)- CK19(+). Semiquantitative analysis of expression levels demonstrated a significant correlation between CK7 and CK19 expression. Of various clinicopathologic parameters, tumor differentiation exhibited a significant correlation with CK7 and CK19 expression. All 15 patients with CK19-positive HCC also had anti-HBc. Log-rank test revealed that CK7 expression, CK19 expression, high aspartate aminotransferase (AST) activity, low albumin concentration, portal invasion, intrahepatic metastasis, and severe fibrosis (cirrhosis) reduced the tumor-free survival rate. Multivariate analysis demonstrated that CK19 expression, intrahepatic metastasis, and severe fibrosis were independent predictors of postoperative recurrence, while CK7 expression was not. Twelve of 15 patients with CK19-positive HCC had tumor recurrence within 2 years after surgery, a significantly higher incidence of early recurrence than for CK19-negative HCC. The incidence of extrahepatic disease, especially lymph node metastasis, was significantly higher for patients with CK19-positive HCC. These findings indicate that CK19 expression is a predictor of early postoperative recurrence due to increased invasiveness.

Apoptosis of T cells in the hepatic fibrotic tissue of the rat: a possible inducing role of hepatic myofibroblast-like cells.

Apoptosis of T cells contributes to the immune homeostasis in inflamed organs. A prominent T-cell infiltration is usually seen in human chronic active hepatitis, being associated with liver fibrosis. In order to demonstrate T-cell apoptosis in the hepatic fibrotic tissue, we induced T-cell infiltration in the fibrotic liver of the rat by injecting concanavalin A (Con A), a T-cell mitogen. Lymphocytes increased in number with a peak at 1 day, preferentially distributing in the fibrotic tissue rather than the parenchyma. They consisted of CD4-positive and CD8-positive cells, and gave the feature of lymphoblasts. Double staining for CD3 and TUNEL demonstrated that T cells underwent apoptosis. Apoptotic cells were more frequent in the fibrotic livers than the normal livers, and were spatially associated with alpha-smooth muscle actin-positive myofibroblast-like cells that possibly derived from hepatic stellate cells (HSCs) and portal fibroblasts through activation. In vitro experiments demonstrated that lymphocyte apoptosis was more frequently induced in the co-culture of Con A-activated splenic T cells/activated HSCs compared to that induced in activated T cells/quiescent HSCs or resting T cells/activated HSCs. The present results indicate that T cells which have extravasated and infiltrated the hepatic fibrotic tissue undergo apoptosis probably through an interaction with myofibroblast-like cells, suggesting the regulatory role of the latter cells in T-cell accumulation in the fibrotic liver.

Granulated metrial gland cells in the murine uterus: localization, kinetics, and the functional role in angiogenesis during pregnancy.

Granulated metrial gland (GMG) cells are a major immune cell population in the murine pregnant uterus, and contribute to the maintenance of pregnancy by functioning as uterus-specific natural killer (NK) cells. In order to reveal their kinetics, activation, and functional roles in pregnancy, we conducted quantitative and immunohistochemical analyses in normal and immuno-modulator-treated mice. Under a light microscope, GMG cells were identified by red cytoplasmic granules in periodic-acid-Schiff (PAS)-stained sections. They progressively increased in number and size with the peak at day 12-14 of pregnancy in the decidua and metrial gland. New vessel formation was most prominent around day 8, and the total vascular area reached the peak at day 13. GMG cells were often located near the blood vessels, and expressed vascular endothelial growth factor (VEGF), suggesting their possible inducing role in angiogenesis during the development of decidua/metrial gland. While blood vessels in the non-pregnant uterus were negative for vascular cell adhesion molecule (VCAM)-1, those in the pregnant one were positive. Treatment with neutralizing antibody against VCAM-1, however, did not decrease the number of GMG cells. On the other hand, mitosis of GMG cells was frequently observed. These data suggest that the increment of GMG cells during pregnancy may largely result from local proliferation in the uterus rather than an increased influx of precursor cells. Although we attempted to induce in vivo activation of GMG cells by administration of interleukin-12 (IL-12) or alpha-galactosylceramide, a potent activator for natural killer-T (NK-T) cells, the number of GMG cells did not appreciably increase. The present study has demonstrated that GMG cells locally proliferate in the pregnant uterus, not being related to VCAM-1 expression by the uterine vasculature or systemic activation of NK cells and NK-T cells, and seem to be involved in angiogenesis in the pregnant uterus through VEGF production.

A murine model of granulomatous colitis with mesenteric lymphadenitis induced by mycobacterial cord factor.

Granulomatous colitis is a major entity of human intestinal diseases. We previously reported that intravenous injection of mycobacterial cord factor (CF), a potent macrophage activator, induced pulmonary granulomas in mice with enhanced production of Th1 cytokines and chemokines. In this study we made a murine model of granulomatous colitis by intramural injection of CF. A single dose of 300 microg CF was injected into the wall of the rat and mouse colon in the form of liposomes. After 1 week granulomas developed at the injection site, extending from the subserosa to the lamina propria, and persisted for longer than 6 weeks. They were composed mainly of ED1-positive macrophages, which often underwent apoptosis, and CD4(+) and CD8(+) lymphocytes, which preferentially infiltrated around the macrophage accumulation. Myofibroblast proliferation was not prominent, and no appreciable fibrosis resulted after the decline of granulomas. Although the intestinal epithelium was involved in inflammation, tissue injuries such as mucosal erosion or ulceration were not induced. When granulomas were formed near the Peyer's patches, they invaded deeply into the lymphoid tissue, producing many small islands. The mesenteric lymph nodes also had many granulomatous islands in the cortex and medulla, but the liver and spleen displayed no granulomatous changes, suggesting that liposomal CF spreads via the lymphatic vessels from the injection site. The CF-induced colonic granulomas associated with mesenteric lymphadenitis will be useful for investigating human granulomatous colitis.

Localization of lymphocyte apoptosis in murine lymphoid tissues after stimulation of natural killer T cells with alpha-galactosylceramide.

Alpha-galactosylceramide (alpha-GalCer) has been reported to induce activation-induced cell death (AICD) in natural killer T (NKT) cells. We undertook this study to demonstrate the distribution of AICD of NKT cells in the lymphoid tissues and differences in frequency between the central and peripheral lymphoid tissues, histologically and quantitatively analyzing the apoptotic figure in the murine spleen, lymph node, and thymus after alpha-GalCer treatment. Lymphocyte apoptosis was identified as a cluster of nuclei with chromatin condensation in hematoxylin-eosin-stained sections, and was confirmed by TUNEL staining, double staining for TUNEL and CD4, and electron microscopy. In the spleen, it appeared at 12 h after alpha-GalCer administration, increased in number, reaching a peak at 24 h, and then falling to a normal level at 72 h. It was preferentially found in the white pulp, especially in the periarterial lymphoid sheath, but was sparse in the red pulp. Alpha-GalCer-induced lymphocyte apoptosis was seen in tumor-necrosis factor (TNF)-deficient mice as well, but was not in lpr/lpr (Fas-deficient) or gld/gld (Fas ligand-deficient) mice. As for the tissue distribution, lymphocyte apoptosis was frequently seen in the paracortex of the lymph node, whereas it was rare in the thymus. These data indicate that alpha-GalCer-induced AICD of NKT cells takes place in the T-cell area of peripheral lymphoid tissues (i.e., the spleen and lymph node) through the Fas/Fas ligand, but not the TNF pathway.

Expression of SPARC by activated hepatic stellate cells and its correlation with the stages of fibrogenesis in human chronic hepatitis.

Secreted protein, acidic and rich in cysteine (SPARC), which functions in tissue remodeling, has been reported to be expressed by myofibroblasts in liver cirrhosis and hepatocellular carcinoma. This study aimed to reveal its expression in chronic hepatitis. Immuno-light and electron microscopy demonstrated that SPARC was expressed by nerve fibers and hepatic stellate cells (HSCs) in the liver parenchyma and myofibroblasts in the fibrous septa. Reaction products were localized in the rough endoplasmic reticulum and nuclear envelope. Serial section analysis demonstrated that SPARC, platelet-derived growth factor receptor-beta, and alpha-smooth muscle actin were co-expressed by HSCs. Quantitative analysis demonstrated that, while SPARC-positive HSCs were sparse in control livers, they significantly increased in number in the livers with chronic hepatitis. There were, however, no significant differences in number among the grades of activity, the stages of fibrosis, or etiology (virus-infected or autoimmune, hepatitis B virus or hepatitis C virus). In liver cirrhosis, however, they significantly decreased in number. The present results indicate that SPARC is expressed by activated HSCs in chronic hepatitis, suggesting the involvement of SPARC in hepatic fibrogenesis after chronic injuries.

Hemodynamics in the microvasculature of thioacetamide-induced cirrhotic rat livers.

BACKGROUND/AIMS: To evaluate the hepatic microcirculatory changes in liver cirrhosis, in vivo microscopic findings were assessed quantitatively in cirrhotic rats. METHODOLOGY: Using in vivo microscopy, the blood flow velocity through terminal portal venules and terminal hepatic venules, and their diameters were measured. The rats were classified into a normal group, fibrosis group, and cirrhosis group, histopathologically. To estimate intrahepatic blood flow of the liver surface, laser-Doppler flowmeter was used for the three groups, and portal venous pressures were measured. RESULTS: Blood flow velocity through terminal portal venules increased significantly in cirrhosis rats. However, among the three groups, there were no significant differences with blood flow velocity through terminal portal venules, diameters of terminal portal venules and terminal hepatic venules. Portal venous pressure and intrahepatic blood flow of the liver surface increased significantly. CONCLUSIONS: These data indicate that pre-sinusoidal alterations to hemodynamics become manifest in the liver cirrhosis, which might be related to intrahepatic shunt formation.