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Peripheral blood lymphocytes and the various lymphocyte fractions from patients with cancer of the colon were cultivated with target cells (P-4788) derived from the colon cancer. Changes in the surface ultrastructure during tumor cell destruction were studied by scanning electron microscopy (SEM). P-4788 cells adhering to the coverslip showed various surface activity. The surfaces of some cells were relatively flat; others were smooth or had fine granules. Still other cells were villous, round or had marked blebs. When host lymphocytes were added to the target cells, adhesion of the two cell groups began by many fine projections. After incubation for 6 h, some lymphocytes had adhered to the target cells. Many lymphocytes had adhered to the target tumor cells by 24--48 h incubation. Ultimately the tumor cells became swollen and disrupted. Most lymphocytes adherent to the target cells had few microvilli. Lymphocytes after elimination of phagocytes by carbonyl iron treatment also adhered readily. Some target cells showed adhesion with lymphocytes passed through nylon-wool columns, although the number of lymphocytes adhering was fewer than in the case of lymphocytes not passed through nylon-wool columns. T cells were collected from lymphocytes that form rosettes with SRBC by isolation with NH4Cl. They had markedly elongated microvilli which in places were sparsely scattered and tended to be localized on the side, a finding which suggests loss of cell activity by the time of SEM. Only a few T cells adhered to target cells and they seemed to be T cells without activity. It was thought that there are cytotoxic cells among T cells and that the co-existence of T cells, non-T cells and monocytes caused target cell destruction.

In order to locate the target cells for malignant transformation by BK virus (a human papova virus) in hamster brain, electron microscopic observation of tumor originally induced in hamster brain by BK virus was performed. With light microscopy, the BK virus-induced tumor (Vn 17) bore a close resemblance to human malignant ependymoma. Under the electron microscope, numerous microvilli and few cilia were visible on the surface of the tumor cells. These tumor cells were joined to each other by desmosomes. Gap junctions were not observed. Multilayered cuboidal cells were observed around the lumen and blood vessels in the tumor. With regard to fine structure, three types of Vn 17 cells were recognized; ependymal like cells, tanycytes with prominent cell processes, and undifferentiated cells with few cytoplasmic organelles. There was no basal lamina between the ependymal cells and the connective tissue stroma. The Vn 17 cells showed some similarity to the ultrastructural features of the epemdymal cells of newborn rabbits, suggesting that the target cells for Vn 17 may be cells related to ependyma. Malignant transformation of the cells would be initiated in the early stages after BK virus inoculation into the brain of newborn hamsters.

The autopsy case of an 80-year-old female with pseudomyxoma peritonei arising in the left ovary is reported. The patient was admitted with complaints of anorexia, sense of fullness and abdominal distension of two months' duration, and died of intestinal obstruction four months later. The autopsy revealed extensive tumor dissemination over the entire peritoneal cavity without any visceral invasion or distant metastasis. A part of the sigmoid colon showed marked stenosis and perforation with abscess formation. Histologically, the tumor was composed of various sized multiple cysts which were completely or incompletely lined by a layer of mucin-producing columnar epithelial cells with moderate nuclear hyperchromatism, and of a papillary pattern in some parts, indicating low grade malignancy.

A heat stable cell growth inhibiting factor was isolated from rat liver microsomes by hot salt extraction, ethanol fractionation and the hot phenol method. The factor was contained in the RNA fraction (designated as mhRNA). mhRNA inhibited the growth of mouse fibroblast (L-929) cells at a relatively low concentration (55 microgram/ml of culture medium). The molecular weight of mhRNA was about 27,000 and the base composition was guanine and cytosine rich.

Purification of antilymphocyte antibody (ALA) from patients with systemic lupus erythematosus (SLE) was achieved by immunoabsorption and elution. Human tonsil cells or thymocytes were used as absorbents. Complement dependent microcytotoxicity tests showed that, in comparison to the parent sera, the eluate from tonsil cells was eight times, and that from thymocytes four times, more active. Antinuclear activity was eliminated by elution. The ALA was almost entirely IgM, IgG being involved in only a few cases. IgA lacked cytotoxic activity. ALA was directed at both T- and B-cell surface determinants, which suggests that, in SLE, it has a heterogeneous biological composition.

Three patients at various stages of remission from leukemia died following the development of massive liver necrosis within only 4-6 days. All had either hepatitis B surface antigen or antibody in their sera, and two of them experienced severe epigastric pain before the onset of liver injury. Hepatitis B surface antigen appeared in two of these patients after remission from leukemia. Serum gamma-globulin levels increased with decreasing doses of prednisolone and other antileukemic drugs, and hepatic cell necrosis occurred extensively. Localization of hepatitis B surface antigen in their livers revealed a strong positive reaction in the phagocytic cells. These observations strongly suggest that hepatitis B virus may be causally related to the fulminant hepatic failure at least in two of the reported leukemic patients.

Mesosomes of Staphylococcus aureus were examined morphologically under the electron microscope. Three different methods of specimen preparation (thin section, freeze-fracture, and negative staining) were used to eliminate artifacts due to sample processing. Mesosomes were rarely seen in intact cells but were quite distinct in autolysed cells incubated in 1.2M sucrose -0.33M acetate buffer (pH 5.8) at 25 degrees C. The phospholipid content increased by 20% of the control as autolysis proceeded. Since the plasma membrane did not show any other significant changes, the development of mesosomes during autolysis was shown to be a real event. Most of the well-developed mesosomes were found at the septum in negatively stained specimens. Initial wall-lysis occurred at this site, suggesting a close relationship between autolysis and the development of mesosomes in S. aureus.

A 26-year-old female with Bartter's syndrome associated with Graves' disease is reported. This patient had a history of Graves' disease from the age of 22 and anti-thyroid drug (Methimazole) had been administered for 2 years. Thyroid function returned to normal but general fatigue and polyuria continued. Hypokalemia was diagnosed at 25 years of age and she was referred to our hospital for evaluation. Blood pressure was normal and laboratory data revealed normal thyroid function, hypokalemic alkalosis, high plasma renin activity and high plasma aldosterone concentration. She showed normal pressor sensitivity to norepinephrine infusion, grossly diminished pressor sensitivity to exogenous angiotensin II infusion compared with the normal. A renal biopsy specimen showed juxtaglomerular cell hyperplasia. Electron microscopy confirmed lacis cell (agranular cell) proliferation.

Galectins are beta-galactoside binding mammalian lectins and they share homologous carbohydrate recognition domains. To date, 11 members of galectin family have been cloned and identified. They have been shown to play roles in diverse biological events, such as embryogenesis, oncogenesis, adhesion and proliferation of the cells, receptor for advanced glycation end products, mRNA splicing, bacterial colonization, apoptosis, and in the modulation of the immune response. The mechanisms by which galectins exert these diverse effects remain largely unknown. However, the elucidation of multi-functional proteins belong to galectin family are going to open new fields in clinical science including diagnosis and therapy of autoimmune disorders, cancers, and vascular complications in diabetes and hypertension.</P>

The immune status of thirteen living and related kidney transplant recipients with stable allografts were examined. The immunological assays consisted of a mixed lymphocyte reaction (MLR), cell-mediated lympholysis (CML) assay, interleukin-2 (IL-2) production in mixed lymphocytes culture (MLC) and IL-2 receptor (IL-2 R) expression on MLC cells. The suppression rates of the monoclonal antibodies (mAbs) against IL-2 R were tested on MLRs. The stimulation indices (SI) of the MLR against both donor and third-party cells increased compared with those of pretransplantation. The MLC responder cells stimulated by donor cells produced detectable amounts of IL-2, these amounts were lower than those by third-party cells. The MLC cells against donor cells expressed IL-2 R alpha and beta chains to the same degree as those against third-party cells. Anti-IL-2 R mAbs equally inhibited the MLRs between recipient and donor or third-party cells. Cytotoxic T lymphocytes (CTL) against donor cells were not generated, even with the addition of recombinant IL-2 in any of recipients except one, while anti-donor CTL had been detected prior to transplantation and the CTL against third-party cells were induced in posttranspalnt CML

assays. These results indicate that the clonal anergy phenomenon might mediate the specific CTL unresponsiveness observed in kidney transplant recipients and the anergy phenomenon might serve in the long-term acceptance of allograft.

Hepatitis C virus (HCV), discovered in 1989, is the major causative agent of parenteral non-A, non-B hepatitis worldwide. Following the development of a method of diagnosing HCV infection, it became apparent that HCV frequently causes chronic hepatitis. Persistent infection with HCV is implicated in liver cirrhosis and hepatocellular carcinoma. Current worldwide estimations suggest that more than 170 million people have been infected with HCV, an enveloped positive single-stranded RNA (9.6-kilobases) virus belonging to the Flaviviridae. The HCV genome shows remarkable sequence variation, especially in the hypervariable region 1 of the E2 protein-encoding region, and globally, HCV appears to be distributed with more than 30 genotypes. Complicated "quasispecies" and frequent mutations of viral genomes have also emerged. The HCV genome encodes a large polyprotein precursor of about 3,000 amino acid residues, and this precursor protein is cleaved by the host and viral proteinases to generate at least 10 proteins in the following order: NH2-core-envelope (E1)-E2-p7-nonstructural protein 2 (NS2)-NS3-NS4A-NS4B-NS5A-NS5B-COOH. These viral proteins not only function in viral replication but also affect a variety of cellular functions. Although several explanations have been proposed, the mechanisms of HCV infection and replication in targeted cells, the mechanism of persistent viral infection, and the pathogenesis of hepatic diseases (hepatitis or hepatocellular carcinoma) are all poorly understood. A major reason why these mechanisms remain unclear is the lack of a good experimental HCV replication system. Although several classical trials using cultured cells have been reported, several new, more promising experimental strategies (generations of infectious cDNA clone, replicon, animal models, etc.) are currently being designed and tested, in order to resolve these problems. In addition, new therapies for chronic hepatitis have also been developed. The enormous body of information collected thus far in the field of HCV research is summarized below, and an overview of the current status of HCV molecular virology of HCV is provided.</P>

Nephrin, a gene product of the congenital nephrotic syndrome of the Finnish type (NPHS1), is a 1242-residue putative transmembrane protein of the immunoglobulin family of cell adhesion molecules. The expression of this gene is localized in rat and human glomerular epithelial cells. Here we report the expression of nephrin in various tissues other than the kidneys in mice. The expression of nephrin mRNA in various tissues of mice, including the kidneys, testes, spleen, thymus and brain, were first investigated by the RT-PCR method, and it was shown that a high level of nephrin mRNA could be detected in the testes of mice 1-6 weeks old. In situ hybridization revealed the expression of the nephrin gene in the Sertoli cells. Additionally, immunofluorescent staining studies indicated that nephrin was colocalized with anchoring protein ZO-1 in the mouse testis. From these results, it is inferred that nephrin is an important component of the barrier system in testes.

Allergic and chronic inflammation of the airway is regarded as the main pathogenesis of bronchial asthma, in which adhesion of inflammatory cells requires the expression of adhesion molecules. Thus, to clarify the role of fibronectin (FN) in the airway inflammation of bronchial asthma, FN levels in plasma and bronchoalveolar lavage fluid (BALF) from bronchial asthmatics were determined. FN concentrations in plasma and BALF were measured by enzyme-linked immunosorvent assay (ELISA) in 17 asthmatic patients and 10 healthy controls to elucidate the role of FN in allergic inflammation. The mean FN/albumin (Alb) level in the BALF of asthmatic patients was 2.973 micrograms/mg, which was significantly higher than that of healthy controls (0.727 microgram/mg). Non-atopic asthmatics showed a significantly higher level of FN in their BALF in comparison with atopic asthmatics, although the ratio of FN to albumin showed no significant difference. FN levels in BALF correlated significantly with total cell density (r = 0.71, P < 0.05) and alveolar macrophage density (r = 0.64, P < 0.05). FN levels in plasma did not correlate with those in BALF. In conclusion, increased FN in BALF, which was produced locally in the airways of asthmatic patients, is actively involved in the regulation of allergic inflammation.

CD14 is a pattern recognition receptor on myeloid cells and plays a pivotal role in an innate immune system that is responsible for Gram-negative and Gram-positive bacteria infection. Lipopolysaccharide (LPS), a cell wall component of Gram-negative bacteria, can induce production of a large quantity of proinflammatory cytokines into the circulation mediated by CD14-mediated macrophages and monocytes. These cytokines eventually cause septic shock. Several in vitro and in vivo studies have shown that suppression of a CD14 function by a CD14 antibody led to an inhibition of the production of proinflammatory cytokines such as TNF-alpha, IL-1 beta, and IL-8. In the present study, we found that CD14 antisense oligonucleotide (ODN) can prevent lethal LPS shock in D-galactosamine-sensitized mice. This ODN inhibited CD14 expression in a mouse macrophage cell line, RAW264.7, and suppressed production of TNF-alpha in LPS-stimulated RAW264.7 cells. Furthermore, we designed a consensus antisense ODN that could hybridize human and mouse CD14 RNA, and we evaluated its efficacy. The consensus antisense ODN rescued mice primed with Mycobacterium bovis bacillus Calmette-Guerin (BCG) from the LPS-induced lethal shock. In this model, the CD14 antisense ODN down-regulated LPS-elicited CD14 expression in the liver, resulting in a decrease in LPS-induced TNF-alpha production. These findings suggest that the CD14 antisense ODN is distributed in the liver and efficiently suppresses LPS-induced TNF-alpha production by reducing CD14 expression on Kupffer cells. This CD14 antisense ODN may be useful for the development of a therapeutic agent against sepsis and septic shock.

We performed an immunohistochemical analysis of 2 major DNA mismatch repair proteins, human Mut L homologue-1 (hMLH1) and human Mut S homologue-2 (hMSH2), in hepatocellular carcinoma (HCC) using 33 biopsied and 58 surgically resected specimens, as well as 30 samples from non-cancerous livers. In well-differentiated HCCs, the immunoreactivity for these antigens was well preserved, and the staining intensity was stronger compared to the surrounding liver tissues. However, among 41 moderately-differentiated and 9 poorly-differentiated HCCs of the resected cases, hMLH1- and hMSH2-positive cells were significantly reduced in 19 (38%) and 9 (18%) cases, respectively. In 9 resected tumors, the expression of both of these antigens was reduced. Moreover, in 41 tumors of differing histological grades, 10 and 5 tumors for hMLH1 and hMSH2, respectively, contained a less-differentiated area with a reduced number of immunoreactive cells. The samples from non-cancerous biopsied liver and fetal autopsy tissue were well immunostained for both hMLH1 and hMSH2. We confirmed in this series that the hMLH1 and hMSH2 defect did commonly occur in high-grade HCCs, and that it might play a role in tumor progression.

The genotoxic effects of occupational exposure to ionizing and non-ionizing radiation were investigated in 25 physicians and nurses working in hospitals and in 20 individuals working at radio-relay stations. Examination was conducted by chromosome aberration analysis of peripheral blood lymphocytes. The data showed that total number of chromosome aberrations in people exposed to ionizing and radio-frequency radiation (4.08 +/- 0.37 and 4.35 +/- 0.5 on 200 scored metaphases, respectively) were almost equally higher than those of non-irradiated subjects. The increase was in proportion to the number of individuals having more that 5-aberration/200 metaphases. Acentric fragments comprised the most frequently seen type of aberration. The average numbers in examined groups (11.8 x 10(-3) and 14.8 x 10(-3) per cell, respectively), were significantly higher than 4.2 x 10(-3), which was observed in controls, unexposed individuals. Dicentric fragments were also frequent (4.8 x 10(-3) and 6.25 x 10(-3), respectively, vs. 0.52 x 10(-3) in control). In contrast, the frequency of chromatid breaks increased only after ionizing radiation (3.8 x 10(-3) vs. 0.26 x 10(-3) in control). A positive correlation between the total number of chromosome aberrations and cumulative 6-years dosage was also found. The data emphasized the dangerous effects of prolonged exposure to both types of radiation and indicated that chromosomal aberration analysis should be obligatory for individuals working at radio-relay stations.

Administration of ferric nitrilotriacetate (Fe-NTA) in vivo causes acute renal tubular injury and finally induces renal cell carcinoma. There is accumulating evidence that these processes involve free radicals generated by Fe-NTA. To study the mechanism of renal carcinogenesis by Fe-NTA, we attempted to induce malignant transformation of primary cultured renal cells by treatment with Fe-NTA. When primary cultured renal cells (PRC) were treated continuously with Fe-NTA, all of the PRC died without transformation. On the other hand, when PRC were treated intermittently with Fe-NTA, transformed epithelial colonies were observed at 3 weeks after the first treatment. The established transformed cell line (RK523) showed drastic morphological transformation, grew in soft agar, and formed tumors when transplanted into athymic nude mice. These results indicate that the balance between cytotoxicity and mutagenecity is important for Fe-NTA induced transformation. The RK523 cell line may be a useful model for studying renal carcinogenesis in vitro.

The structure of the human genome is almost completely elucidated and the life sciences will now aim for a general and integrated study of gene expressions and the functional elucidation of proteins. In such a study, various new techniques have been developed, and DNA microarray technology is the most representative one. As for the DNA microarray techniques, several thousands to tens of thousands of gene segments are immobilized on a glass slide at high density, and cDNA probes prepared from specific cells or tissues are hybridized on the slides from which gene expression profiles are obtained at one sweep in a short time. The present development of this technique and its possible application to medicine-related fields are described.</P>

To clarify the involvement of the caspase family in the pathway of NO-induced chondrocyte apoptosis, osteoarthritis (OA) cartilage obtained from 8 patients undergoing total hip arthroplasty were used for histopathological study. Cartilage samples taken from non-fibrillated areas of femoral head resected during surgery for femoral neck fracture were used for comparison. DNA fragmentation of chondrocytes was detected by the nick end-labeling (TUNEL) method. Apoptosis was further confirmed by transmission electron microscopy. The distributions of nitrotyrosine (NT), caspase-3, and -9 were examined immunohistochemically. The populations of apoptotic as well as NT-, caspase-3-, and -9-positive cells were quantified by counting the number of cells in the superficial, middle, and deep layers, respectively. The TUNEL-positive cells were observed primarily in superficial proliferating chondrocytes, clustering chondrocytes, and deep-layer chondrocytes of OA cartilage. Few positive cells were seen in the proliferating chondrocytes in the middle layer. Positive reactions for caspase-3 and -9 were observed in chondrocytes in similar areas. Histological OA grade showed significant correlations with the mean populations of apoptotic chondrocytes (% apoptosis) over the 3 areas. The populations of NT-positive cells (% NT) over the same areas also showed significant correlation with OA grade. Positivity for caspase-3 closely correlated with the OA grade, % apoptosis and %NT. It was concluded that caspase-3 and -9 could play a role in NO-induced chondrocyte apoptosis in OA cartilage.

A 69-year-old woman was admitted to our hospital because of anal bleeding and fatigue. The patient was previously diagnosed as having Evans' syndrome on the basis of hematological examination and had been treated with predonisolone for 8 years. On admission, severe anemia and thrombocytopenia were noted. Colonoscopy and Barium enema studies demonstrated an irregular tumor with hemorrhagic ulceration in the rectum, which was histopathologically confirmed as an adenocarcinoma. After red blood cells and platelets were transfused, and the patient was treated with high-dose gammaglobulin, predonisolone, and camostat mesylate, the platelet count gradually increased and hemolysis was well controlled. The patient then underwent Hartmann's operation and splenectomy without any postoperative complications. Predonisolone and high-dose immunoglobulin therapy in a rectal cancer burdened patient with Evans' syndrome is considered useful in combination with surgical treatment. This is the first case report of rectal carcinoma resection in a patient with Evans' syndrome.