Ikuko Torii

Ferritin selectively suppresses delayed-type hypersensitivity responses at induction or effector phase.

The effect of ferritin on the delayed-type hypersensitivity (DTH) response and Arthus-type reaction as assessed by footpad reaction using methylated human serum albumin, human serum albumin, or sheep red blood cells as antigens was investigated. Intraperitoneally administered ferritin was short acting and suppressed either induction or expression of DTH depending on the time of ferritin injection although it did not inhibit the antibody-mediated inflammatory response, the Arthus reaction. Investigation of ferritins effect on the primary antibody response revealed that the number of IgG plaque-forming cells (PFC) was moderately decreased but IgM PFC were not. These results indicate that the afferent limb, ferritin selectively suppresses antigen presentation and/or clonal expansion of effector cells of cell-mediated immunity, but not that of the antibody response. Antigen presentation by Ia-positive cells and/or lymphokine-responsive inflammatory mononuclear cells at the efferent limb of DTH is suggested to be affected by ferritin. This conclusion is based upon the observations of successful TDTH effector cell transfer from sensitized but ferritin-treated donors and of successful reversal of ferritin-induced suppression of expression of DTH by supplementing normal bone marrow-derived cells containing Ia-positive ones. Thus our in vivo experimental system might be useful for the differential analysis of immunopathological lesions such as a T-cell-mediated, monocyte-dependent and an antibody-mediated inflammatory lesions.

Establishment of a human preadipose cell line, HPB‐AML‐I: Refractory to PPARγ‐mediated adipogenic stimulation

In this study, we established a unique cell line, HPB‐AML‐I (AML‐I), from peripheral blood mononuclear cells collected from a patient with acute myeloid leukemia (AML: M1). Morphological and phenotypical analyses of the established AML‐I cells demonstrated that they belong to a preadipocyte cell line as indicated by their storage of lipid droplets and expression of surface antigens similar to those found on bone marrow stromal cells (MSC). Through cell culture under adipogenic conditions, effective differentiation of AML‐I cells into adipocytes was induced by an adipogenesis inducing cocktail (INC) made up of a mixture of methylisobutylxanthine, hydrocortisone, and indomethacin. By contrast, activation of peroxisome proliferator‐activated receptor (PPARγ), which plays a key role in lipids metabolism and is highly expressed in AML‐I cells, decreased the number of lipid droplets in AML‐I cells. Here we report the establishment of a unique human derived‐preadipocyte cell line, AML‐I, and its bi‐directional adipogenic response to different type stimulation, i.e., one is a refractory response to troglitazone, a well‐known adipogenic stimulator, and a positive response to INC, an adipogenesis induction cocktail. These results suggest that, based on the adipogenic response, there might be some distinct lineages in human adipocytes and that the unique differentiation of AML‐I cells should be useful for analyzing both the differentiation and regulation of human preadipocytes. J. Cell. Physiol. 197: 42–52, 2003© 2003 Wiley‐Liss, Inc.

Differential endocytotic characteristics of a novel human B/DC cell line HBM-Noda: effective macropinocytic and phagocytic function rather than scavenging function

In order to characterize a novel human B cell‐lineage dendritic cell line (B/DC line) as an antigen‐presenting cell (APC), we compared three types of endocytosis (micropinocytosis via a clathrin‐coated pit, macropinocytosis via membrane ruffling, and phagocytosis) among myeloid‐related, macrophage (Mφ) cell lines and a B/DC line. In the present examination, we used a unique human dendritic cell (DC) line, HBM‐Noda (Noda). Flow cytometric and immunocytochemical analyses revealed that Noda not only expresses some DC markers, but also it expresses some B‐cell associated markers. Noda shows strong capacities to stimulate allogenic T cells, to produce immunoglobulin G (IgG), and to perform immunoglobulin gene rearrangment. These data strongly suggest that Noda is a B‐cell lineage DC line. The endocytic differences among these cell lines were as follows. (1) The level of micropinocytosis of Noda was significantly less than that of conventional human Mφ cell lines, and the formation of a clathrin‐coated pit was not observed in Noda. (2) The level of macropinocytosis of Noda was also smaller than that of conventional Mφ cells indicating that the active membrane ruffling of Noda induces rapid recycling. (3) Phagocytosis of opsonized sheep red blood cells (SRBC) was performed more efficiently in Noda than in other Mφ cell lines. Collectively, these data suggest that in human bone marrow cells, we can identify a unique DC subtype, B/DC line, which develops through a lymphoid DC‐differentiation pathway, and DC in this lineage plays an important role in the host immune response because of its effective uptake of a variety of size of antigens by using the skilful membrane ruffling and surface receptors

An autopsy case of Pena-Shokeir syndrome: severe retardation of skeletal muscle development compared with neuronal abnormalities.

An infant with multiple joint ankyloses, facial anomalies, and pulmonary hypoplasia, features similar to the phenotype of Pena-Shokeir syndrome, was examined at autopsy. Histological examination of the skeletal muscles revealed many small muscle fibers in a mixed, not group, distribution, although the structure of them was normally arranged. Histochemical assessment of adenosine triphosphatase (ATPase) activity of the iliopsoas muscle demonstrated the failure of the differentiation into type I fibers and the retardation of the skeletal muscle. At the same time, severe pulmonary hypoplasia, which was the likely cause for the retardation of the respiratory system, was found. In contrast to these numerous pathologic changes in the skeletal muscles, no significant abnormalities were observed in the central nervous system except for a somewhat immature external appearance; however, an examination of the spinal cord could not be carried out. Overall, this pattern of pathology suggests the possibility that developmental disorders of the mesenchyme are the primary contributors to the pathogenesis of Pena-Shokeir syndrome, while the immaturity of the central nervous system is involved to a lesser degree.

Constitutive expression of granulocyte-colony stimulating factor receptor on a human B-lymphoblastoid cell line

The present study demonstrated that a human B‐ cell line derived from non‐Hodgkins lymphoma, HCF‐MLpN, constitutively expressed G‐CSF receptor on the cell surface. G‐CSF binding to the cell surface was shown by immunofluorescence staining using biotinylated G‐CSF preparation and analysed by flow cytometry. Specific binding of G‐CSF to the cells was shown by pretreatment with unlabelled G‐CSF. In the radioreceptor assay and Scatchard plot analysis using radiolabelled ligand, MLpN cells revealed a single species of binding site with an equilibrium dissociation constant of 167 (153–182) pM and a maximal binding site per cell of 1076 (1044–1116). The G‐CSF receptor mRNA transcript was exhibited in the RNA from MLpN cells by reverse transcriptase polymerase chain reaction procedure. [3H]thymidine incorporation and trypan blue exclusion showed that the G‐CSF receptor was capable of transducing the growth signal to HCF‐MLpN cells. A small fraction of fresh B blasts from six patients with B‐cell lymphoma and leukaemia displayed G‐CSF binding by two‐colour immunofluorescence staining. In contrast, a panel of seven B‐cell lines was negative for the binding to biotinylated G‐CSF preparation. These results suggest that the phenotype of G‐CSF binding may be lost during the culture. The expression of G‐CSF receptor in HCF‐MLpN cells appeared to be exceptional.

A human B-lineage dendritic cell line, HBM-noda and its potential role in human T-cell leukemia/lymphoma virus type I infection.

An Epstein–Barr virus‐transformed B‐cell line, HBM‐Noda (Noda), that has a dendritic morphology as well as several characteristic features of dendritic cells (DC) has been established. We therefore refer to Noda as B‐lineage DC. Although human T‐cell leukemia/lymphoma virus type I (HTLV‐I) exhibit substantial cellular tropism, the roles of DC in HTLV‐I infection remain unknown. To further clarify the characteristics of Noda cells, we performed infection experiments using a concentrated HTLV‐I fraction from the adult T‐cell leukemia cell line, HPB‐ATL‐2. Noda, as well as other cell lines examined, were sensitive to HTLV‐I infection as detected by proviral DNA using polymerase chain reaction, but most infected Noda cells underwent necrosis within 7 days. The most striking feature of Noda cells was the abundant expression of viral antigen (p19) on the cell surface following infection (approximately day 4), probably due to strong viral adsorption. In cocultivation experiments using Noda cells at day 1 of post‐infection and peripheral blood activated T cells, we detected a few (1.3%) viral antigen expressing T cells after 5 days of coculture by flow cytometry. These results suggest that B‐lineage DC such as Noda cells play a role in the establishment of HTLV‐I infection at an early phase.

MD41, a novel T helper 0 clone, mediates mast-cell dependent delayed-type hypersensitivity in mice

In a previous study on mouse, we have shown that delayed‐type hypersensitivity (DTH) could be classified into two types according to MC requirement. The first type of DTH could be elicited by sensitization with methylated human serum albumin (MHSA) in complete Freunds adjuvant (CFA) in both wild type and mast‐cell deficient (W/Wv) mice. The second type could be elicited by MHSA in incomplete Freunds adjuvant (IFA) sensitization in wild type but not W/Wv mice. While the former was related to classic tuberculin (tbc)‐type DTH, the latter appeared to be a novel mast‐cell dependent DTH (MD‐DTH). In order to investigate the mechanism of MD‐DTH, in this study, we generated an effector T‐cell clone (MD41) from lymph node cells of MHSA in IFA‐sensitized mice and analysed its pattern of cytokine production. Our results from cytokine assays show that following antigen stimulation, MD41 cells produce significant amounts of the T helper 1 (Th1) cytokine interferon‐γ (IFN‐γ) as well as the Th2 cytokines interleukin (IL)‐4 and IL‐10. In addition, double staining for IL‐4 and IFN‐γ revealed that MD41 cells produce both Th1‐ and Th2‐type cytokines simultaneously, which suggest that MD41 represents a Th0 clone rather than a mixture of Th1 and Th2 clones. Adoptive transfer of MD41 cells into wild‐type mice resulted in the development of DTH skin reactions similar to those produced by active sensitization, with very similar histological findings. However, DTH skin reactions could not be induced in W/Wv mice unless first reconstituted with normal bone marrow MC (BM‐MC). Therefore, our study suggests that in conjunction with tissue MC, MD41, a less‐polarized MD‐DTH‐derived Th0 clone, is capable of developing murine DTH to the same extent as strongly polarized Th1 cells and mediates MD‐DTH rather than tbc‐type DTH.

An autopsy case of acquired immune deficiency syndrome (AIDS) with preceding aplastic anemia.

A case of acquired immunodeficiency syndrome (AIDS) with preceding aplastic anemia is reported. The patient was a 36 year old female who had been diagnosed as having aplastic anemia 10 years before and thereafter had received multiple transfusions. Human immunodeficiency virus (HIV)‐seropositivity was revealed 10 months prior to her death, but no particular clinical signs indicating HIV infection, pre‐AIDS or onset of AIDS were recognized before serological diagnosis, although the slow progression of leukopenia was noted along with thrombocytopenia. Her general condition deteriorated during the last 10 months accompanied by an acute decrease In the CD4/CD8 ratio. Autopsy revealed full‐blown AIDS: systemic aspergillosis, progressive multifocal leukoencephalopathy, Epstein‐Barr virus‐related B cell lymphoma arising in the diaphragm and severe lymphocyte depletion in the lymph nodes and spleen. Markedly hypo‐plastic bone marrow was considered to be primarily attributable to the aplastic anemia but the affection of AIDS was not excluded. The possible transmission route of HIV and the effect of the preceding aplastic anemia on the infection and clinical course of AIDS are discussed.