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T Hibi

Publications and source records attributed to T Hibi.

At least 163 records · Page 9Linked to original sources
PubMed1988

T lymphocyte subpopulations and immunoglobulin-containing cells in the colonic mucosa of ulcerative colitis; a morphometric and immunohistochemical study.

T lymphocyte subpopulations and immunoglobulin containing cells in the colonic mucosa of 25 patients with ulcerative colitis have been studied using an indirect immunoperoxidase technique. In ulcerative colitis a marked increase in the population of Leu 3a positive cells (helper/inducer T cells) and IgG containing cells was observed in the mucosal lamina propria. In the intraepithelial spaces, a remarkable decrease in the population of Leu 2a positive cells (suppressor/cytotoxic T cells) and a marked increase in the number of Leu 3a positive cells were revealed. There was a very significant correlation between the population of IgG containing cells and the ratio of Leu 3a positive cells to Leu 2a positive cells in the lamina propria of patients with ulcerative colitis. These results suggest that an imbalance of mucosal immunoregulatory T cells and an increased production of IgG occurred in correlation with inflammatory activities of ulcerative colitis.

Adolescent↗
PubMed1987

Increased respiratory burst of leukocytes in inflammatory bowel diseases--the analysis of free radical generation by using chemiluminescence probe.

Respiratory burst of leukocytes was determined in Crohn's disease, intestinal Behçet's disease and ulcerative colitis by using chemiluminescence assay. Oxygen-derived free radicals of monocytes in Crohn's disease and those of polymorphonuclear leukocytes in intestinal Behçet's disease were significantly raised as compared with those of controls. In ulcerative colitis, respiratory burst activities of both polymorphonuclear leukocytes and monocytes were found to be highly associated with the disease activities. These results suggest that active oxygen species from leukocytes may participate in the formation of intestinal mucosal lesions in inflammatory bowel diseases via auto-oxidative process.

Adult↗
PubMed1987

Alteration of T cell maturation and proliferation in the mouse thymus induced by serum factors from patients with ulcerative colitis.

Recently it has been reported that patients with ulcerative colitis (UC) often have thymus abnormalities, although the precise mechanisms which induce those abnormalities remain unclear. We have examined the effect of serum fractions from patients with UC and other colonic diseases on mouse thymus to clarify the possible existence of factors which have thymus growth activity. These fractions were separated from sera of patients with UC by gel filtration and anion exchange high performance liquid chromatography. In mice given UC serum fractions; (i) remarkable increases in weight and total cell number of the thymus were observed from day 4 to day 9; (ii) a significant increase in the number of peanut agglutinin (PNA)+ thymus cells was demonstrated using flow cytometry on day 9; (iii) on quantitative analysis of surface antigens the percentage of Lyt-2+ thymus cells decreased and that of L3T4+ thymus cells increased remarkably on day 13; the number of bright Thy-1.2+ cells and of dull Lyt-1+ cells increased. In contrast, the serum fractions from patients with other colonic diseases and from normal persons caused little change in mouse thymus throughout the study. The results suggest that factors fractionated from the serum of patients with UC disturb intra-thymic T cell maturation and enhance the proliferation of thymus cells.

Animals↗
PubMed1986

Phenotype, frequency, and EBV responsiveness of human marrow B and pre-B cells.

We have purified subpopulations of B lineage cells from human adult (rib) bone marrow by cell sorting and panning. Limiting dilution analysis was then used for a clonal analysis of cells able to secrete IgG, IgA, or IgM spontaneously or after infection with EBV. Nonproliferating, high rate IgG or IgA producers occurred at frequencies of about one per 1000 marrow mononuclear cells. Their frequency and Ig production was unaffected by EBV, and they appeared not to express EBNA after exposure to EBV. These cells were Ia+, B1+, and over 85% expressed sIg of the IgM/D (up to 75%) and/or IgG/A isotypes (40 to 60%). B cells committed to the secretion of IgM represent 2 to 10% of marrow B lymphocytes. They were found to be Ia+/B1+/B2+/CALLA- and C3b receptor (CR3)-cells, and most (greater than 90%) required infection with EBV and proliferation to develop into IgM-producing lymphocytes. Thirty to 40% of these cells did not express Ig (H or L chain) on their surface, and therefore resembled pre-B cells at the beginning of the 4- to 5-wk culture period. Proliferating pre-B cells from adult human marrow have been described, but their conversion into IgM-producing cells has not been formally demonstrated. Although EBV induces IgM production, the expression of EBNA, and several rounds of cell division in these cells, the induction of stable (greater than 5 wk) growth transformation represents a rare event in these pre-B cells: in several thousand limiting dilution wells, not a single culture of sIg-cells showed stable growth transformation. The dichotomy between EBV-induced high-rate IgM responses and absent growth transformation discriminates activation and transformation as distinct aspects of EBV-induced B cell "responses", and suggests that cellular properties play critical roles for viral transformation. We propose a model in which cellular target genes for transforming sequences in the EBV genome are transiently expressed during B cell differentiation.

Adult↗
PubMed1986

Limiting dilution analysis of the B cell compartment in human bone marrow.

Mononuclear cells (MNC) obtained from adult rib specimen were investigated for their capacity to produce immunoglobulin (Ig) in vitro. Using limiting dilution analysis 3 populations of B lineage cells could be distinguished. The first produces Ig in culture without any intentional activation. These cells are strictly nonproliferating and sustain extraordinary secretory rates of 5 X 10(7)-10 X 10(7) molecules IgG, IgA or IgM/cell/h for at least 2 weeks. They occur at frequencies of 1 X 10(-4)-10 X 10(-4) (marrow MNC) or represent 1-5% of marrow B cells. Following exposure to infectious Epstein-Barr virus (EBV), these cells do not (a) proliferate, (b) express EBV-determined nuclear antigens (EBNA), (c) enhance their secretory rates or (d) show secretory activity for prolonged time. These cells are therefore EBV resistant. If these cells produced their antibody at similar rates in vivo, then their frequencies would suggest that they could provide up to 2/3 of daily synthetic rates for IgG and IgA and 20-30% of the daily IgM production. The second population of marrow B cells is exclusively committed to IgM production. Following exposure to EBV these cells proliferate, express EBNA and begin to secrete IgM. The third population represents 90% of marrow B cells. In our hands, these cells are unable to produce Ig in vitro.

Antibody-Producing Cells↗
PubMed1986

Epstein-Barr virus-induced IgE production in limiting dilution cultures of normal human B cells.

The induction of in vitro IgE production in human B cells from normal, nonatopic donors has been difficult and somewhat controversial. We report that IgE production is consistently observed in limiting dilution cultures of in vitro Epstein-Barr virus (EBV)-infected normal human B lymphocytes. The frequency of IgE-committed, EBV-responsive cells ranged from 1/810 to 1/10 000 B lymphocytes, and it was similar in peripheral (blood, tonsil) and central (bone marrow) tissue sites. Poisson distribution analysis of these limiting dilution cultures suggested that IgE-committed B cells comprise 0.1-1% of all EBV-responsive B lymphocytes.

B-Lymphocytes↗
PubMed1986

Lymphocyte function in human bone marrow. III. Isotype commitment, metabolic and secretory characteristics of immunoglobulin producing cells.

We have examined the functional and metabolic properties of immunoglobulin (Ig)-secreting cells in adult (rib) bone marrow, the tissue which provides the major proportion of serum Igs. In the absence of polyclonal activators, high rate Ig production (1-2 micrograms/day/10(6) marrow mononuclear cells) was sustained from the beginning of culture throughout 2 weeks and then declined. Ten percent of the Ig secreted was of the IgM isotype and IgG/A made up the remainder at equal proportions. Infection of marrow cells with Epstein-Barr virus (EBV) induced the production of large amounts of IgM, but virtually all IgG/A-committed cells were refractory to stimulation with EBV. Both EBV-induced and the "spontaneous" Ig production was inhibited by cycloheximide, but only EBV-induced IgM production was blocked by hydroxyurea and gamma-irradiation. The polyclonal activators PHA and PWM induce suppressor-T-cell activity in marrow cultures. This suppressor function involves nonproliferating cells which acquire suppressive activity 3-4 days after mitogenic activation. Prednisolone and cyclosporine A modulate Ig production in cultures of peripheral lymphocytes but had no effect on Ig secretion in marrow cell cultures. This observation was reminiscent of the absent or at best marginal short-term effects on in vivo serum Ig levels which is typical for these drugs. Our observations suggest that the marrow Ig-producing B-lymphoid cell compartment shows major differences to other tissue sites with respect to properties of the Ig-secreting cells the immunoregulatory activities able to control their function, and the response of these cells to clinically important drugs.

Adult↗
PubMed1985

Immunomorphological localization of adenosine deaminase in rat tissues during ontogeny.

Immunomorphological methods were used to localize adenosine deaminase in tissues of the rat at different stages of ontogeny. In the thymus, lymphocytes began to express significant amounts of the enzyme with the appearance of demarcation between the cortex and medulla at 17 days of gestation. At any stage of ontogeny studied, strong adenosine deaminase staining was seen predominantly in cortical thymocytes. In the spleen and lymph node, the enzyme was initially detected in T cell areas, whereas primary follicles did not show positive adenosine deaminase staining. During further development, the enzyme was demonstrated in some lymphocytes of germinal centres and plasma cells. In the duodenum, epithelial cells of villi and the neck of crypts showed positive adenosine deaminase staining whereas no staining for the enzyme was observed in the epithelial cells of the base of crypts. Strongly positive staining for adenosine deaminase appeared in plasma cells of the lamina propria by four weeks after birth. The transient positive reaction for the deaminase could be recognized in epithelial cells of tubules of the kidney during late foetal and early postnatal development. The tubules of adult rats did not stain for the enzyme. In the cartilage of 15-day foetuses, positive adenosine deaminase staining was seen only in perichondrial cells and hypertrophic cells. Kupffer cells in the liver and endothelial cells of blood vessels stained positively for the enzyme at every stage of ontogeny studied.

Adenosine Deaminase↗
PubMed1985

Microangiographic findings of massive intestinal bleeding in a patient with Crohn's disease: a case report.

A 16 year old man with complaints of abdominal pain, diarrhea, high fever and loss of body weight was made a diagnosis of Crohn's disease. During the administration, he had intestinal obstruction and several episodes of massive intestinal bleeding. Selective angiography of the superior mesenteric artery demonstrated the bleeding site in the ileum. Microangiography of the surgical specimens revealed abrupt interruptions of arteriae rectae in the submucosa indicating the bleeding site from the diseased intestine.

Adolescent↗
PubMed1985

Lymphocyte function in human bone marrow. I. Characterization of two T cell populations regulating immunoglobulin secretion.

We analyzed the regulation of immunoglobulin (Ig) production in short-term cultures of human (rib) bone marrow cells. In contrast to blood or tonsil cell cultures, large quantities of IgG and IgA, but not IgM, were secreted by unstimulated marrow cells. The addition of pokeweed mitogen or phytohemagglutinin resulted in the suppression of this Ig secretion. Both mitogens induced the production of high levels of interleukin 2 (IL 2) in marrow cultures, and the addition of IL 2 alone mimicked the suppressive effect of mitogens. Incubation of marrow cells with Epstein Barr virus resulted in enhanced Ig secretion, primarily of the IgM isotype. The addition of mitogen or IL 2 suppressed Ig production in these cultures as well. The mitogen-induced suppression of Ig secretion in stimulated or unstimulated marrow cultures was inhibited by the monoclonal anti-TAC (IL 2 receptor) antibody. Cell separation experiments indicated that the induction of suppressor activity in marrow cultures involved two distinct populations of marrow-resident T lineage cells. The first population responds to activation by mitogens with the production of IL 2. This population has a surface phenotype appropriate for helper T cells. The second T cell population expresses T8 and TAC determinants. These cells acquire suppressor cell activity after exposure to IL 2. The expression of suppressor function does not require additional (e.g., mitogenic) activation signals. The IL 2-dependent marrow suppressor T cells represent a newly recognized T lymphocyte subset. The regulatory pathway delineated may be important for the regulation of antibody formation in bone marrow, the major site of Ig production in man.

Bone Marrow↗
PubMed1985

Demonstration and characterization of immunosuppressive factors in sera from patients with Crohn's disease.

The effect of sera from 17 patients with Crohn's disease, 8 with ulcerative colitis or 5 with intestinal tuberculosis on the proliferative response of mouse spleen cells induced by phytohemagglutinin (PHA) was studied. Sera from patients with Crohn's disease markedly suppressed the blastogenesis of mouse spleen cells (S.I. = 6.8 +/- 2.0, % suppression = 83%), as compared with normal sera (S.I. = 41.0 +/- 5.2, p less than 0.001, % suppression = 0). Conversely, ulcerative colitis sera did not suppress the blastogenesis of mouse spleen cells (S.I. = 43.5 +/- 8.7, % suppression = -6%), nor the sera of intestinal tuberculosis (S.I. = 38.9 +/- 4.0, % suppression = 6%). Thus, we confirmed the possible existence of immunosuppressive factors in Crohn's disease. Moreover, immunosuppressive factors in Crohn's disease were characterized for biochemical properties. The approximate molecular weight is 45,000 estimated by diafiltration and gel filtration on a Sephadex G-75 column. Analytical isoelectric focusing showed an increased amount of acidic protein in fractionated sera (m.w. ranging 30,000-50,000) from patients with Crohn's disease and ulcerative colitis, in comparison with that in normal sera. Furthermore, the main peak of this acidic protein in Crohn's disease was an isoelectric point (pI) of 2.8, while the pI of that from ulcerative colitis was 3.0. These results suggest that qualitative differences of such acidic protein may serve to discriminate between the sera of Crohn's disease and ulcerative colitis.

Adolescent↗
PubMed1984

Ecto-5'-nucleotidase. I. Expression in human normal and neoplastic lymphoid cell lines representing sequential stages of B-cell differentiation.

The possible association of ecto-5'-nucleotidase (5'-NT) with differentiation of B-cells was explored with the use of normal and neoplastic lymphoblastoid cell lines representing sequential stages of B-cell maturation. There was no relationship between patterns of enzyme expression in the cell lines and immunoglobulin (Ig) secretion, chromosome constitution, proliferative rate, cell volume, or the presence of B1 and B2 antigens. Pre-B-cell lines, which were negative for surface Ig or Ig secretion but positive for cytoplasmic mu-chains, showed the presence of 5'-NT, whereas 9 of 11 lymphoma cell lines, Burkitt's or non-Burkitt's type, both secreting and nonsecreting, did not exhibit enzyme activity. Four myeloma cell lines and 13 of 15 normal B-cell lines were positive for 5'-NT. These results suggested that 5'-NT was present in pre-B-cells and in some very early B-cells. 5'-NT usually disappeared from early and some intermediate B-cells and reappeared in mature B-cells and plasmacytoid cells.

5'-Nucleotidase↗
PubMed1984

Ecto-5'-nucleotidase. II. Effect of 12-O-tetradecanoylphorbol 13-acetate on the expression of enzyme in normal and neoplastic B-cell lines.

Immature B-cells, including B-cell lymphoma lines, are often deficient in ecto-5'-nucleotidase (5'-NT) activity. 12-O-Tetradecanoylphorbol 13-acetate (TPA) was shown to be capable of inducing maturation toward plasmacytoid-like cells in immunoglobulin (Ig)-secreting B-cell lines. An attempt was made to induce the enzyme in 5'-NT-negative B-cell lymphoma lines with TPA to clarify the relationship between 5'-NT and B-cell differentiation. After 3 days in the presence or absence of TPA, these cell lines were examined morphologically, and their 5'-NT activity, Ig secretion, surface Ig, and Ia, B1, and B2 antigens were estimated. Neither Ig secretion nor 5'-NT activity was induced by TPA in any of 4 nonsecreting cell lines studied. Ig secretion was significantly increased in 4 of 5 lg-secreting cell lines. Two of these inducible cell lines, JD 38 and ST 486, became positive for 5'-NT activity and acquired morphologic characteristics of plasma cells after culture with TPA. The lymphoma cell line JD 38 was transplanted into nude mice and gave rise to a solid tumor. Although the tumor cells remained negative for 5'-NT, they could be induced by TPA to express both the enzyme activity and plasmacytoid-like appearance. These data suggested that in the Ig-secreting B-cell lymphoma lines, there was an association between the inducibility of 5'-NT and the capacity of these cell lines to undergo plasma-cytoid-like transformation in response to TPA.

5'-Nucleotidase↗
PubMed1984

Characterization of thymus cells in hyperplastic thymuses in patients with myasthenia gravis and ulcerative colitis with monoclonal antibodies.

Recently, increasing attention has been paid to thymic relevance to pathogenesis in some autoimmune diseases. In this report, the thymus cells from 7 patients with myasthenia gravis (MG) and 6 patients with ulcerative colitis (UC), who had undergone thymectomy for complication of thymic hyperplasia, were studied. The thymus cells were characterized with monoclonal antibodies (Anti-Leu-2a and Anti-Leu-3a) which define human T-cell surface antigens. Although the control thymus consisted of 82-94% of thymocytes which were reactive with Anti-Leu-2a and 90-95% of cells reactive with Anti-Leu-3a, in UC patients both Leu-2a positive thymus cells (38-56%) and Leu-3a positive cells (68-82%) were decreased. Concerning MG thymocytes, Leu-2a positive cells were also decreased (66-81%), but the percentage of Leu-3a positive cells did not show a remarkable change (86-90%) compared with control thymocytes. Considering the above results and many reports telling functional and populational abnormalities of peripheral immunocompetent cells, the process of intra-thymic T-cell maturation may be impaired in these autoimmune diseases.

Adult↗
PubMed1984

Induction of impaired activation of lymphocytes by suppressive factor in Crohn's disease patients.

Lymphocyte proliferative response to phytohemagglutinin (PHA) and relevance of serum factors to the response were studied in 12 patients with Crohn's disease (CD). The lymphocyte proliferative response was markedly reduced in patients with Crohn's disease (S.I. = 38.8 +/- 36.8) (mean +/- SD), as compared with normal controls (S.I. = 100.6 +/- 28.6) (p less than 0.01). In addition, the effect of sera from patients with CD or 10 patients with ulcerative colitis (UC) who had extremely impaired lymphocyte responsiveness to PHA on the proliferative response of normal lymphocytes to PHA was also measured. Sera from CD patients had a marked suppressive effect on the blastogenesis of normal lymphocytes (S.I. = 46.4 +/- 28.5), as compared with normal sera (S.I. = 126.2 +/- 14.7) (p less than 0.001). On the other hand, UC sera did not suppress the blastogenesis of normal lymphocytes (S.I. = 114.9 +/- 27.7). Moreover, serum immunosuppressive acidic protein (IAP) levels in patients' sera were measured by single radial immunodiffusion assay. A marked increase in serum IAP levels was revealed both in CD patients (780 +/- 470 micrograms/ml) and in UC patients (601 +/- 278 micrograms/ml), as compared with normal controls (376 +/- 92 micrograms/ml) (p less than 0.001). But there was no precise correlation between the suppressive effect of sera and serum IAP levels in patients with CD. Thus, we demonstrated an impairment of the lymphocyte responsiveness to PHA in CD patients and the possible existence of immunosuppressive factors which is not identical with IAP in the sera from patients with CD.

Adult↗
PubMed1983

Circulating antibodies to the surface antigens on colon epithelial cells in ulcerative colitis.

The fluorescence activated cell sorter (FACS) was used for detecting circulating antibodies to the surface antigens on isolated colon epithelial cells (anti-colon antibodies) by indirect immunofluorescence. Anti-colon antibodies were found in the serum of 30 of 41 (73%) patients with ulcerative colitis. This incidence is much higher than one established in earlier reports by application of indirect immunofluorescence to colon tissue using the fluorescence microscope. The results suggest that FACS analysis is very useful for detecting antibodies to colon specific antigen.

Adult↗