Purification and characterization of a novel arginine-specific cysteine proteinase (argingipain) involved in the pathogenesis of periodontal disease from the culture supernatant of Porphyromonas gingivalis

A novel arginine-specific cysteine proteinase, termed "argingipain," was purified from culture supernatants of Porphyromonas gingivalis, an anaerobe commonly associated with progressive periodontal disease, by conventional chromatographic techniques. The purified enzyme was found to be composed of a single polypeptide of M(r) approximately 44,000. Analysis of the enzymatic properties revealed several distinctive features for this enzyme. The proteolytic activity is absolutely thiol-dependent, but the enzyme also has in part the characteristics of both metallo and serine endopeptidases, as shown by the inhibition of activity by metal chelators, chymostatin, and the chloromethyl ketones of tosyl-L-lysine and tosyl-L-phenylalanine. However, internal protease inhibitors, such as cystatins, tissue inhibitor of metalloproteinases, and alpha 1-antichymotrypsin, have no effects on the activity, suggesting its evasion from normal host defense systems in vivo. Despite its narrow specificity for synthetic substrates containing Arg in the P1 site and hydrophobic amino acids in the P2 or P3 sites, the enzyme extensively degrades collagens (types I and IV) and immunoglobulin G. Most important, the enzyme has the ability to disrupt the functions of polymorphonuclear leukocytes, as shown by its inhibitory effect on the generation of active oxygen species from the activated cells. Further, the enzyme is found to be produced by all of the species of P. gingivalis examined, but not by other bacteria. These results suggests that argingipain plays a key role as a major virulence factor from P. gingivalis in the development of periodontal disease via the direct destruction of periodontal tissue components and the disruption of normal host defense mechanisms.

Clinical course and long-term prognosis of Crohn's disease in Japan

The long-term outcome of Crohn's disease was reviewed in 74 patients who had a history of more than 10 years (range 10.8-27.3) since disease onset. The observation period was between 4.3 and 18.5 years, the mean and SD being 10.6 +/- 3.1 years. The means and SD of age at onset and final observation were 21 +/- 7 and 37 +/- 8 years, respectively. Fifty-eight of the 74 patients had not undergone bowel resection at the time of diagnosis; of these 58, 31 (53.4%) had an operation for the disease during the follow-up period. Thus, of the 74 patients, 47 (63.5%) (these 31, plus the 16 who had undergone bowel resection at the time of diagnosis) had an operation at least once during a follow-up period of 10 years or more. The cumulative operation rates 5, 10, and 15 years after onset in the 74 and 58 patients above were 18.9%, 6.9%, and 40.8%, and 34.8%, 49.1%, and 46.0%, respectively. The corresponding figures 5 and 10 years after diagnosis in all 74 patients and the 58 patients were 32.3% and 28.6% and 47.3% and 46.3%, respectively. There were no significant differences in the incidence of operation rate in relation to anatomical involvement. Cumulative reoperation rates 1, 3, 5, and 10 years after the first operation in the 31 patients who were operated on during the follow-up period were 3.4%, 6.9%, 25.5%, and 51.7%, respectively. Three patients died, the causes of death in one being directly related to Crohn's disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Split tolerance between spleen and lymph node cells in severe combined immunodeficiency mice grafted with AKR fetal liver cells

Severe combined immunodeficient (SCID) mice defective in stem cells for T and B cells appear to be an ideal host for construction of chimeric mice. When bone marrow cells are used as a source of stem cells, however, host SCID mice do not always show sufficient reconstitution. In this study, fetal liver cells from AKR embryos were transplanted into SCID mice without prior irradiation. This treatment induced full reconstitution of lymphopoiesis as evaluated by flow cytometry analysis and serum Ig production 2 months after transplantation. Thus, fetal liver cells seem to be a better source for reconstitution of SCID mice than bone marrow cells. Lymph node (LN) cells of these mice (FLT mice) had no proliferative or cytotoxic activities against either host-type (C.B-17) or donor-type (AKR) spleen cells. However, spleen cells from FLT mice exhibited marked proliferative and cytotoxic activities against C.B-17 cells, with no activities against AKR cells. Split tolerance against C.B-17 cells in spleen and LN cells was not a transient phenomenon, since similar results were obtained from a cytotoxic T lymphocyte assay 4 months later. In spite of the strong host reactivity in vitro, aberration of clonal deletion or development of a graft-versus-host disease was not seen in FLT mice. As IL-2 induced the host reactivity of LN cells in a mixed lymphocyte reaction, potentially host-reactive T cells were present in LN but were rendered anergic. Tolerance in FLT mice seems to be regulated by a peripheral mechanism. We supposed that the split tolerance in FLT mice was induced by the different antigenicity between the spleen and LN.

A gD homologous gene of feline herpesvirus type 1 encodes a hemagglutinin (gp60)

A gene-encoding glycoprotein D (gD) homologue of feline herpesvirus type 1 (FHV-1) was identified and sequenced. It was located within an EcoRI 4.3-kbp fragment in the middle of the unique short region. The primary translation product of the gD homologous gene is predicted to consist of 374 amino acids with a molecular weight (MW) of 43.2 kDa. Comparative analysis among gD counterparts of other herpesviruses revealed that six cysteine residues which correlate with disulfide bond structure were conserved, and the amino acid sequences had homologies of 32.6% with bovine herpesvirus type 1 gIV, 29.1% with pseudorabies virus gp50, 28.3% with equine herpesvirus type 1 gD, and 22.0% with herpes simplex virus type 1 gD. When the gD homologue was expressed in COS cells and examined by indirect immunofluorescence and immunoprecipitation assays, it was recognized only by monoclonal antibodies (MAbs) reactive with gp60 which have virus-neutralizing and hemagglutination (HA)-inhibition (HI) activities. This expressed product had a MW of approximately 60 kDa and was shown to be a hemagglutinin by HA and HI tests with the MAbs. These results suggest that the gD homologue of FHV-1 is a hemagglutinin.

[Clinical study of pneumonia in elderly patients using transtracheal aspiration (TTA)]

A clinical study was conducted to clarify the clinical state of pneumonia in elderly patients using transtracheal aspiration (TTA). Without prior administration of antibiotics, S. pneumoniae was the most clinically significant in both elderly and non-elderly groups whether the onset of pneumonia was hospital acquired pneumonia or community acquired pneumonia. Compared to the non-elderly group, multiple pathogens were isolated more frequently in the elderly group. Analysis about host factors showed that the number of underlying diseases per patient was more along those with poorer general conditions in the elderly group. The Brinkmann Index was also significantly higher in the elderly group. Clinical examinations before onset of pneumonia indicated that serum total protein, albumin and DNCB skin reaction were significantly lowered in the elderly group. Over the clinical course, the prognosis was poorer and the incidence of adverse reactions of antibiotics tended to be more in the elderly group. These results suggest that a complex clinical background exists for pneumonia of elderly people, related to poorer prognosis. Therefore, more cautious and meticulous care should be provided to elderly patients with pneumonia.

Distribution of apoptosis-mediating Fas antigen in human skin and effects of anti-Fas monoclonal antibody on human epidermal keratinocyte and squamous cell carcinoma cell lines

Fast antigen is a cell surface protein that mediates apoptosis. Using immunohistological, flow cytometry and electron microscopic analyses, we investigated the expression of Fas antigen on various skin tissues, and on cultured SV40-transformed human epidermal keratinocyte cell line KJD and human skin squamous cell carcinoma cell line HSC. The Fas antigen was widely distributed in skin components such as the keratinocytes in the lower portion of the epidermis, epidermal dendritic cells, endothelial cells, fibroblasts, apocrine glands, eccrine sweat glands, sebaceous glands, some normal melanocytes and infiltrating lymphoid cells. It was also strongly expressed on the keratinocytes of lichenoid eruptions seen in lupus erythematosus and lichen planus, and on the spongiotic or acanthotic epidermis seen in chronic eczema, adult T-cell leukaemia/lymphoma (ATLL) and atopic dermatitis. Its expression was closely correlated with lymphoid infiltrating cells and it was strongly expressed in lymphoid neoplastic cells, particularly ATLL cells, and fibroblasts seen in dermatofibroma. However, the antigen was not detected on basal cell epithelioma cells, some malignant melanomas or any junctional naevi. The cell lines KJD and HSC strongly expressed the Fas antigen, and crosslinking of the Fas antigen by an anti-Fas monoclonal antibody induced apoptosis of these cell lines. These results indicate that the apoptosis-mediating Fas antigen may play an important role in normal skin turnover and cell differentiation, in immune regulation of skin tumours, and in the pathogenesis of various skin diseases.

Alteration in regional brain neuropeptides following intracerebroventricular infusion of excitotoxins in rats

We determined regional brain concentrations of somatostatin (SS), neuropeptide Y (NPY) and arginine-vasopressin (AVP) in 3- and 13-month-old rats. We also examined the effects of the excitotoxins, ibotenic acid (IA), kainic acid (KA), and quinolinic acid (QA) on regional levels of brain neuropeptides in rats. Excitotoxins were infused continuously into the lateral ventricle for 14 days using an osmotic minipump. Our results indicate that; (1) NPY in the brain is especially vulnerable to aging, compared to AVP. (2) IA induces a decrease in brain regional concentrations of neuropeptides and the effects are different from those of other excitotoxins, for example, KA and QA. (3) These effects of IA on neuropeptides may be dependent on the age of the animals when exposed and on the dose of IA.

The phylogenetic relationships of the saturn-shaped ascospore-forming species of the genus Williopsis Zender and related genera based on the partial sequences of 18S and 26S ribosomal RNAs (Saccharomycetaceae): the proposal of Komagataea Gen. Nov

The partial base sequences of 18S and 26S rRNAs of strains of Williopsis and Saturnospora species were analyzed. In the three regions partially sequenced, the higher base differences were observed in the strains examined of the three species, W. californica, W. mucosa, and W. pratensis, compared with those of W. saturnus var. saturnus (type species of genus Williopsis), W. beijerinckii, W. mrakii, W. saturnus var. subsufficiens, W. suaveolens, P. membranaefaciens (type species of genus Pichia), C. matritensis (type species of genus Citeromyces), and S'spora dispora (type species of genus Saturnospora): the percent similarities were 52-82 in positions 493-622, 130 bases, of 26S rRNA, and the number of base differences was 28-6 in positions 1611-1835, 225 bases, of 26S rRNA, and the number of base differences was 25-4 in positions 1451-1618, 168 bases, of 18S rRNA. In the 18S rRNA partial base sequencings, W. mucosa had an identical base sequence with P. anomala (identical to H. anomala, type species of genus Hansenula). Based on the sequence data obtained, the taxonomic positions of the three Williopsis species mentioned above are discussed. The genus Zygowilliopsis Kudriavzev was postulated to be retained and emended, and a new genus, Komagataea was proposed for W. pratensis with a new combination, Komagataea pratensis.

Relationship between body composition and cardiorespiratory fitness in Japanese junior high school boys and girls

This study attempted to evaluate the influence of body composition on cardiorespiratory fitness as represented by maximal oxygen uptake (VO2max) in junior high school boys and girls. The subjects were judged apparently healthy. Measurements of VO2max during an incremental treadmill exercise testing as well as measurements of body composition were compared between obese boys and girls, 12 to 15 years old, and age- and height-matched nonobese boys and girls. Analyses of the data revealed that statistically significant (P < 0.01) mean differences between the obese and nonobese groups were observed for body mass (BM), percentage body fat, and body fat content. Fat-free mass (FFM) of obese boys was significantly larger than nonobese boys. There were significant differences between obese and nonobese groups irrespective of sex, when VO2max was expressed as milliliters of oxygen per kilogram of BM per minute. In contrast, no significant group differences were found in VO2max expressed as ml per kg of FFM per min. No significant differences existed either for absolute VO2max between the obese girls and the nonobese girls due almost entirely to the similarity in FFM between these two groups. Significant correlations were found both in boys (r = -0.742) and girls (r = -0.843) between VO2max (ml/kg BM/min) and percentage body fat, thereby indicating the striking effects of excess body fat. These results in the present study support the general belief that obesity accentuates exercise intolerance and low aerobic capacity.

Initial events and T cell activation in lymphokine-mediated allergic responses in patients with hen egg allergy

Specific induction of IL2-responsiveness by ovalbumin-stimulated lymphocytes was studied in patients with hen egg allergy. Fluorescence-activated cell sorter analysis of the cells showed that the IL2-absorbing and IL2-responding cells mainly consisted of CD3+2+4+8-45RA+ cells that may act as helper cells for IgE production and/or as effector cells for delayed type hypersensitivity. beta-Chains (P75) of IL2 receptors were involved in ovalbumin-induced IL2 responsiveness of the patients' lymphocytes, whereas the alpha-chains (p55) were expressed on normal lymphocytes stimulated with ovalbumin as well. Adhering mononuclear cells from patients allergic to ovalbumin but not to Dermatophagoides farinae (Df) were pulsed with ovalbumin antigen then added to a T cell-rich population. After five days of culture, we evaluated cell growth for IL-2 sensitivity during an additional 3-day culture in the presence of IL-2. Responder cells from the patients, which were cocultured with ovalbumin-pulsed autologous adhering cells, acquired IL2 responsiveness; whereas, those cultured with Df-pulsed adhering cells did not. This reaction was specific for antigen. The monoclonal antibody to HLA-DQ (Leu 10) and HLA-DP (HLA-DP) frameworks, but not the one to the HLA-DR framework (OKIa1), blocked the antigen presenting cells ability to induce responses. T Cell-rich responder cells depleted of CD4+ cells did not acquire IL2-responsiveness, whereas the depletion of CD8+ cells had no effect. As a whole, the results indicate that DQ-bearing and/or DP-bearing adhering cells have a key function in presenting ovalbumin-antigen to allergen-specific responder T cells that very likely belong to CD4+ subsets.

The phylogenetic relationships of the hat-shaped ascospore-forming, nitrate-assimilating Pichia species, formerly classified in the genus Hansenula Sydow et Sydow, based on the partial sequences of 18S and 26S ribosomal RNAs (Saccharomycetaceae): the proposals of three new genera, Ogataea, Kuraishia, and Nakazawaea

The twenty-seven strains of the hat-shaped ascospore-forming, nitrate-assimilating species, formerly classified in the genus Hansenula, of the genus Pichia were examined for their 18S and 26S rRNA partial base sequencings. All the strains examined were separate phylogenetically from the type strain of P. membranaefaciens (type species of genus Pichia). Based on the sequence data obtained [by number of base differences (five or more) with P. anomala and base sequences on fingerprint segment] in the 18S rRNA partial base sequences, these species were divided into seven groups. Group I, including P. anomala (identical to H. anomala, type species of genus Hansenula), P. canadensis, P. muscicola, P. silvicola, P. subpelliculosa, P. americana, P. bimundalis, P. ciferrii, P. syndowiorum, P. bispora, and P. fabianii, corresponded to the genus Hansenula Sydow et Sydow. Groups II and III were comprised of P. capsulata and P. holstii, respectively. Group IV included P. angusta, P. minuta var. minuta, P. minuta var. nonfermentans, P. philodendra, P. glucozyma, and P. henricii. Groups V, VI, and VII included P. jadinii, P. petersonii, and P. dryadoides, respectively. The nitrate assimilation-negative species, P. wickerhamii was phylogenetically distant from P. membranaefaciens. The seven groupings are discussed phylogenetically and taxonomically. For Groups IV, II, and III, the three new genera were proposed as Ogataea, Kuraishia, and Nakazawaea, respectively, with the type species, O. minuta (identical to P. minuta), K. capsulata (identical to P. capsulata), and N. holstii (identical to P. holstii).

Expression of membrane alkaline phosphatase activity on gingival fibroblasts in chronic inflammatory periodontal disease

We investigated the expression of membrane alkaline phosphatase (ALP) activity on fibroblasts in inflamed gingiva from 7 patients with adult periodontitis. ALP activity was ultrahistochemically detected by a cerium-based capture method. The degree of ALP activity was estimated by morphometric analysis of the percentage of the perimeter on which ALP reaction product was deposited. Fibroblasts in the non-inflammatory connective tissue were surrounded by bundles of collagen fibrils, and the majority of these fibroblasts showed ALP-negative or weakly ALP-positive reaction. By contrast, fibroblasts in the inflammatory connective tissue were either surrounded by a non-collagenous substance or in contact with inflammatory cells, and the majority of these fibroblasts showed a strong ALP-positive reaction. These results suggest that the expression of membrane ALP activity on gingival fibroblasts is induced by microenvironmental changes associated with the loss of contact between the cells and the extracellular collagenous matrix during inflammatory reactions.

Beta 2-microglobulin modified with advanced glycation end products induces interleukin-6 from human macrophages: role in the pathogenesis of hemodialysis-associated amyloidosis

Recently, we demonstrated that beta 2-microglobulin (beta 2M) of amyloid deposits in hemodialysis-associated amyloidosis (HAA), a serious complication leading to hemodialysis arthropathy, is modified with advanced glycation end products (AGEs) of the Maillard reaction. In the present study, to elucidate the possible involvement of AGEs-modified beta 2M (AGE-beta 2M) in the pathogenesis of HAA, we examined the effect of AGE-beta 2M on macrophage production of interleukin-6 (IL-6), an important cytokine for osteoclastogenesis and bone resorption. Purified AGE-beta 2M from long-term hemodialysis patients, but not normal beta 2M, stimulated synthesis and secretion of IL-6 from macrophages. Similar effects were also induced by in vitro-prepared AGE-beta 2M (normal beta 2M incubated with glucose for 60 days in vitro). These findings suggested a potential role of AGE-beta 2M in the pathogenesis of HAA.

Immunohistochemical examination on the localization of macrophages and plasma cells in induced rat periapical lesions

To investigate the role of plasma cells and macrophages in the development of periapical lesions, we immunohistochemically examined the distribution of these inflammatory cells in experimental induced rat periapical lesions after pulpectomy. The number of ED1-positive mononuclear cells increased rapidly, reached a plateau which remained stable between days 10 and 60, and subsequently decreased. Immunoglobulin (Ig)-bearing plasma cells appeared after 60 days, and, of these, IgG-bearing plasma cells were predominant after 90 days. The radiographic and histopathological findings indicated the development of bone destruction at 10 days which continued until 60 days; tissue repair began to take place after 90 days. The results suggested that macrophages had a close relation to bone destruction and that plasma cells might participate in tissue repair rather than the development of periapical lesions.

Carrier-state infection of feline T-lymphoblastoid cells with feline calicivirus

The susceptibility of feline T lymphocytes to feline calicivirus (FCV) in vitro was investigated using feline T-lymphoblastoid cell lines, namely MYA-1 and FL74 cells. The virus titers of supernatants in FCV-infected MYA-1 and FL74 cell cultures increased rapidly, and FCV antigens were also detected in the FCV-infected cells. There were slight differences in the molecular weights of capsid proteins expressed in FCV-infected MYA-1, FL74 and Crandell feline kidney cells. MYA-1 and FL74 cells were productively and persistently infected with FCV, and FCV antigens were observed in the FCV-infected cells for more than one month. At 3 months post infection, FCV-infected FL74 cells that stopped producing infectious FCV could be reinfected with FCV. However, no cytopathic effects were observed.

B cells are required as APC for antigen-specific T cell proliferation but not for the differentiation or priming of those T cells

We studied the influences of B cells on functional differentiation of T cells using SCID mice grafted with fetal thymus of C.B-17 mice (TG mice). T cells were shown to be reconstituted in TG mice without B cell development. These mice showed normal DTH response to SRBC and OVA. LN cells of these mice produced cytokines including IL-2, IL-4, IL-6 and IFN-gamma according to Con A stimulation. Thus, majority of T cell functions seem to differentiate in the absence of B cells. However, T cells of TG mice failed to proliferate in response to immunizing antigens in vitro, although they responded well to stimulation with Con A. This unresponsiveness of T cells in TG mice to these antigens was restored when antigen-primed B cells were added to the proliferation assay. Such an inability of T cells in antigen-specific proliferation was not seen in SCID mice grafted with C.B-17 fetal liver cells, in which B cells as well as T cells were efficiently reconstituted (FLT mice). T cell proliferation to immunizing antigen was also abrogated in FLT mice when B cells were depleted from lymphoid population. These results indicate that T cells can functionally differentiate and be primed in the absence of B cells, but they require B cells to proliferate in response to foreign antigens.

Characterization of genomic PIG-A gene: a gene for glycosylphosphatidylinositol-anchor biosynthesis and paroxysmal nocturnal hemoglobinuria

Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired hemolytic anemia characterized by the presence of abnormal subpopulations of blood cells that are deficient in surface expression of glycosylphosphatidylinositol (GPI)-anchored proteins. Recent studies showed that the gene termed PIG-A, which participates in the first step of GPI-anchor biosynthesis, is mutated in the abnormal blood cells from patients with PNH. In this study the genomic PIG-A gene was cloned and characterized to obtain nucleotide sequence information for analyzing somatic mutations of PIG-A in patients with PNH. The PIG-A gene is at least 17 kb long and has six exons. The exon-intron boundaries and 583 bp of the 5' flanking region were sequenced. The 5' flanking region has no TATA-like sequence, but includes four CAAT boxes, two AP-2 sequences, and a CRE sequence, some of which are present in regions necessary for the promoter activity. We report pairs of oligonucleotide primers for polymerase chain reaction that should be useful to amplify and analyze various regions of the PIG-A gene in patients with PNH.