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Biomedical subjects

I Nakashima

Publications and source records attributed to I Nakashima.

At least 181 records · Page 10Linked to original sources
PubMed1991

Deterioration of immune complex solubilization activity of serum by increased concentration of factor D.

We investigated the effect of excess complement factor D on the immune complex solubilization activity (ICSA) of serum. First, we estimated the concentration of factor D, ICSA and the hemolytic activity via the classical complement pathway (CH50) in the sera of 16 healthy individuals and 36 patients on hemodialysis for end-stage renal failure. The serum concentration of factor D in these patients (mean +/- SD: 12.12 +/- 2.38 micrograms/ml) was significantly higher (p less than 0.001) than that in the healthy subjects (1.02 +/- 0.11 micrograms/ml). In this study, peroxidase and antiperoxidase rabbit IgG were used as immune precipitates for ICSA. The ICSA in patients (45.8 +/- 7.4 normal human serum %, NHS%) was significantly lower (p less than 0.001) than that in the healthy subjects (100.2 +/- 12.5 NHS%). There was no difference in CH50 between the sera of the patients (31.8 +/- 2.5) and that of the healthy group (32.4 +/- 2.6). Second, we determined that increasing amounts of purified factor D added to fresh serum resulted in a decrease in ICSA. This occurred in the serum of a healthy individual as well as in that of a patient. CH50 did not change regardless of the concentration of factor D used. There was an increase in C3 conversion in the sera to which purified factor D had been added, as observed by crossed immunoelectrophoresis. It is suggested that ICSA had deteriorated due to the excess of factor D, which had activated the alternative pathway of complement.

Antigen-Antibody Complex↗
PubMed1991

Homotypic aggregation of murine T lymphocytes induced by anti-Thy-1 monoclonal antibodies.

During the course of studies of anti-Thy-1-mediated T-cell activation, we found that anti-Thy-1 monoclonal antibodies (mAb) could induce strong homotypic aggregation of murine T-lineage cells. We demonstrated that anti-Thy-1 mAb-mediated T-cell aggregation started at 10 min and reached maximum level 1 hr after addition of antibody. It was temperature dependent, requiring metabolic energy and cytoskeletal integrity similar to that mediated by phorbol myristate acetate (PMA). But the striking difference between anti-Thy-1 mAb-mediated cell aggregation and PMA-mediated cell aggregation was that the latter but not the former was blocked by anti-LFA-1 mAb. This indicates that, unlike treatment with PMA, anti-CD2 mAb or anti-CD3 mAb, anti-Thy-1 mAb treatment of T lymphocytes does not induce LFA-1 activation for cell adhesion. Murine neuroblastoma cells were not induced to aggregate by anti-Thy-1 mAb treatment, although murine T lymphoma cells were aggregated by anti-Thy-1 mAb. The T-lineage cell specificity of anti-Thy-1-mediated aggregation was further shown by the Thy-1 gene transfection into non-Thy-1 expressing cell lines. Thy-1.1 gene transfected mastocytoma cells were not aggregated by anti-Thy-1.1 antibody.

Animals↗
PubMed1991

Allotype-linked immune response genes: roles in network control of the immune system.

Studies on allotype-linked immune response genes and related genes are overviewed with particular attention to our current results in unique models. Significance of actions of various immune response genes in relation to allelic polymorphism of molecules in the immune system is discussed. The molecules involve immunoglobulins, T cell receptors, major histocompatibility complex and a number of cell interaction molecules, many of which belong to the immunoglobulin superfamily. Differential roles of V-linked and C-linked immune response genes for network control of the immune system, preparing the V structure repertoire, controlling antigen presentation and modulating the effector mechanism, are suggested.

Animals↗
PubMed1990

Inhibitory effect of herpes simplex virus infection to target cells on recognition of minor histocompatibility antigens by cytotoxic T lymphocytes.

Target cell lysis by CTL specific for minor histocompatibility Ag (minor HA), which were generated in (C3H/He x BALB/c)F1 mice immunized with A/J mouse spleen cells, was dramatically reduced by infection of HSV to Neuro-2a (A/J mouse origin) cells as target. The reduction was apparent at 5 h after infection of HSV to target cells, when many viral proteins were produced in the cells. Conversely, MHC-restricted HSV-specific CTL-mediated cell lysis increased time dependently. Using an RNA virus, vesicular stomatitis virus, significant reduction of minor specific CTL-mediated target cell lysis was also found. During the time when this reduction of target cell lysis by HSV occurred, the surface expression of class I H-2Dd molecules was maintained, and anti-H-2a allo-MHC-specific CTL lysed HSV-infected Neuro-2a cells as strongly as uninfected Neuro-2a cells. When HSV-infected or uninfected Neuro-2a cells were treated with Brefeldin A that selectively blocks transportation of newly synthesized proteins out of endoplasmic reticulum, both HSV- and minor HA-specific CTL-mediated cell lyses were blocked. These observations demonstrated that minor HA are continuously synthesized and associated with class I molecules at pre-Golgi and transported via trans Golgi system with quick turnover, and that newly synthesized HSV Ag, which are also associated with class I molecules and transported via the same system, should take the place of intrinsic minor HA and be presented on the surface of the cells to be recognized by MHC-restricted CTL.

Animals↗
PubMed1990

Analysis of PI (phosphatidylinositol)-anchoring antigens in a patient of paroxysmal nocturnal hemoglobinuria (PNH) reveals deficiency of 1F5 antigen (CD59), a new complement-regulatory factor.

FACS analysis together with PIPLC treatment was applied to PI-anchoring antigens such as DAF (decay-accerelating factor, CD55), 1F5 antigen (CD59), CD14 and CD16 on the cell surfaces of blood cells from a normal adult and a male patient with paroxysmal nocturnal hemoglubinuria (PNH). Through the extensive analysis, this patient proved to be completely defective in 1F5 antigen, a newly found complement-regulatory protein, on all the blood cells tested. In normal blood cells such as lymphocytes, monocytes and granulocytes, 1F5 antigen was expressed as one of PI-anchoring proteins. In contrast to most of PNH patients, this patient reserved DAF, CD14 and CD16 at normal levels in his erythrocytes, monocytes and granulocytes. Also, there were no significant differences between the normal adult and the patient in the activities of erythrocyte acetylcholinesterase and granulocyte alkaline phosphatase which were also known to be PI-anchoring enzymes. Thus, deficiency of 1F5 antigen must be deeply related to the clinical symptoms of PNH in this patient.

Adult↗
PubMed1990

Induction of high-grade anti-tumor immunity by use of a recombinant H-2Kb/avian erythroblastosis virus erbB gene transfectant.

The recombinant H-2Kb-erbB gene, encoding for a part of the H-2 class I antigen and the kinase domain of the V-erbB peptide, was successfully introduced into murine mastocytoma P815 variant P1.HTR cells, which resulted in low but significant cell-surface expression of the hybrid gene product. When the chimeric gene transfectant was inoculated into the CDF1 mice, it soon grew but regressed thereafter. The tumorigenicity of this transfectant was lower than the H-2Kb gene transfectant that expressed the H-2Kb antigen at a comparable level. These CDF1 mice that had received the chimeric gene transfectant obtained a high-grade anti-tumor immunity against the challenge of a high dose of parental tumor. Corresponding to these observations, anti-tumor cytotoxic T lymphocytes, which lyse parental P1.HTR cells but not syngeneic L1210 or NS-1 tumor cells, were developed in the peritoneal cavity of mice that had been inoculated with the transfectant and parental tumor. Definite antibody activity binding to parental P1.HTR tumor cells was also demonstrated in the sera of these mice, precipitating 40-kDa, 74-kDa and 98-kDa molecules from the surface of the radiolabeled P1-HTR tumor cells. The results suggested that the chimeric H-2-erB gene transfectant efficiently triggers both cellular and humoral anti-tumor immune responses.

Alpharetrovirus↗
PubMed1990

Molecular and functional identification and purification of complement component factor D from urine of patients with chronic renal failure.

Urine proteins of normal subject and patients with impaired renal function were analyzed by two-dimensional polyacrylamide gel electrophoresis. As a result, a clear spot was detected specifically in urine from patients with obvious renal dysfunction. The isoelectrical point of this unique spot was pH 7.1-7.2 and the flow-rate (Rf) was 0.50-0.55 as that of albumin was 1.0. Partial amino acid sequence analysis revealed that the NH2-terminal to 22nd amino acid sequence was identical with that of complement factor D. We purified 22 mg of this protein (factor D) from 5000 ml of urine from a patient on hemodialysis by three chromatographic steps using DEAE-Sephadex A-50 and Sephacryl S-200. The purified urine factor D gave a single band in sodium dodecyl sulfate polyacrylamide gel electrophoresis at the position of 23 kD, and displayed normal factor D hemolytic activity. The concentrations of factor D estimated by hemolytic assay were 1.9 micrograms/ml of normal serum, less than 0.1 microgram/ml of normal urine, 15 micrograms/ml of patient serum and 50 micrograms/ml of patient urine.

Amino Acid Sequence↗
PubMed1990

Nuclear localization of antigens detected by a monoclonal antibody against a synthetic peptide of rfp finger protein.

A monoclonal antibody (MAb) was generated against a synthetic peptide corresponding to amino acids 148 to 163 of the rfp protein with zinc finger domains. The MAb, designated RFP-1 (IgM), which was positive with the immunizing peptide in enzyme-linked immunosorbent assay, was reactive in immunoblotting with an in vitro translated rfp product as well as with native proteins in cell extracts made from mouse testis and HL-60 human leukemia cell line, both of which were previously shown to express high levels of rfp mRNA. When HL-60 cells were fractionated into nuclear and cytoplasmic components, the protein reactive with RFP-1 MAb was detectable only in the nuclear fraction. By the avidin-biotin complex immunoperoxidase method, this MAb strongly stained over 90% of the nuclei of human and mouse spermatogenic cells, except mature spermatozoon, and of human testicular tumor cells. In other human adult tissues, up to 60% of positive cells were observed. These antibody activities were clearly absorbed by pre-incubation of RFP-1 MAb with the immunizing peptide. These results thus indicated that RFP-1 MAb recognizes a nuclear protein which is expressed at high levels in male germ cells.

Amino Acid Sequence↗
PubMed1990

Cytotoxic T lymphocyte recognition of the H-2-erbB hybrid gene product lacking the complete H-2 domain structure.

The chimeric mouse MHC class I gene derived from a recombinant H-2Kb gene, in which the coding region for a large part of alpha 1 and alpha 2 extracellular domains was replaced with a partial avian erythroblastosis virus erbB gene segment encoding the kinase domain, was successfully introduced into a mouse mastocytoma line P1.HTR (H-2d) and transcribed to mRNA. The transfectant cells expressed the chimeric gene product, which was reactive to a phosphotyrosine-specific antibody. When the chimeric gene transfectant was inoculated into CDF1(H-2d) or BDF1(H-2d/b) mice, it grew at an early time but regressed thereafter. Transfectant-specific as well as parental P1.HTR-specific antibody activities were demonstrated in the sera of these mice. Transfectant-specific cytotoxic T lymphocytes (CTL) were generated in the antigen-sensitized culture of spleen cells from the transfectant-immune mice. The CTL-mediated lysis of target chimeric gene transfectant cells was poorly inhibited by anti-H-2d antiserum, which blocked the lysis of parental P1.HTR cells by anti-tumor CTL developed in parallel. The former was, however, inhibited by either anti-transfectant antiserum or anti-phosphotyrosine antibody, which was ineffective for blocking the latter. Target cell lysis by either anti-transfectant or anti-tumor CTL was blocked by anti-CD8 monoclonal antibody but not by anti-CD4 antibody. It was suggested from these results that the H-2K-erbB hybrid gene product, which lacks complete three-domain class I structure, was recognized by CTL in a manner that was endogenous H-2 class I-independent but CD8-dependent.

Animals↗
PubMed1990

Demonstration of lipid A-binding proteins on murine lymphoma cells using R-mutant gram-negative bacteria as a detector.

Some R-mutant Escherichia coli and Salmonella heavily adhered to murine lymphoma cells of B cell and T cell lineages. This adhesion was primarily mediated by membrane-localized proteins on tumor cells, which bind the polymyxin B-reactive hydrophilic structure of lipis A on bacteria. SDS-PAGE analysis of tumor cell membranes showed that proteins or glycoproteins of MW = around 45Kd, 25-35Kd and around 15Kd preferentially bind lipid A. Various lymphoma cell lines binding the bacteria at different levels possessed lipid A-binding proteins of slightly different compositions. We conclude that lymphoma cells carry not a single but a group of lipid A-binding proteins in their membranes.

Animals↗
PubMed1990

A new method for induction of experimental autoimmune uveoretinitis (EAU) in mice.

Experimental autoimmune uveoretinitis (EAU) was induced in two strains of mice by repeated-immunization protocol. SMA mice (H-2 nondefined) and C57BL/6 mice (H-2b) were immunized with S-antigen mixed with Klebsiella 03 lipopolysaccharide (K03 LPS) repeatedly at intervals of 1 to 4 weeks. Following the tertiary immunization, the mice exhibited histopathological changes of EAU as well as significant immune responses to the antigen. The antigen doses required for successful EAU induction were 4 micrograms or more at each immunization time. The histopathology of EAU was characterized by mild infiltration of mononuclear cells in the retina and the choroid, particularly, at the retinal blood vessels and the photoreceptor cell layer. The anterior segment of the eye was not affected by inflammation, and therefore clinical signs of EAU were not detected even under an operating microscope. Since the mouse is a genetically and immunologically well-defined species, this model is useful for study of immunopathogenic mechanisms of EAU.

Adjuvants, Immunologic↗
PubMed1990

Oncogenicity of the ret transforming gene in MMTV/ret transgenic mice.

We have successfully produced transgenic mice that carry the ret oncogene driven by a mouse mammary tumor virus promoter/enhancer. Mammary and salivary gland adenocarcinomas were developed in a stochastic fashion in these mice. Moreover, premalignant tumors with hyperplastic and dysplastic lesions of Harderian glands and male reproductive tracts frequently occurred at young ages. High expression of the transgene was closely associated with the development of these tumors although the levels of the transgene expression were variable among individuals. In addition, large amounts of phosphotyrosine-containing proteins were detected in cell lysates from mammary and salivary adenocarcinomas by immunoblotting with the anti-phosphotyrosine antibody.

Animals↗
PubMed1990

Modulation by glycyrrhizin of the cell-surface expression of H-2 class I antigens on murine tumour cell lines and normal cell populations.

Glycyrrhizin (GL), a saponin fraction of licorice with defined chemical structure, was shown to display a definite action in vitro augmenting the cell-surface expression of H-2 class I antigens as well as class I gene transcription on various tumour cell lines. The magnitude of augmentation was varied among eight different cell lines tested, but reached more than three times. It was also found that GL enhanced the expression of H-2Dd antigens in some normal cell populations in vivo. The augmentation of H-2 class I antigens on tumour cell lines in vitro was probably not mediated by the interferon, which might have been produced by the cultured cells. These findings may suggest a new immunopharmacological action of GL.

Animals↗
PubMed1989

Induction of antitumor immunity in mice by allo-major histocompatibility complex class I gene transfectant with strong antigen expression.

An allo-major histocompatibility complex class I gene (H-2Kb) was transfected to murine mastocytoma P1.HTR (P815 subline) cells, after which several transfectant clones were obtained. Two clones, which expressed a low level of H-2Kb antigen, grew well and killed the syngeneic DBA/2 mice when they were inoculated ip. These mice lived longer than the mice given injections of the parental P1.HTR tumor. However, one clone, which expressed a high level of H-2Kb antigen, was rejected completely by the syngeneic DBA/2 mice and induced a generation of H-2Kb-specific cytotoxic T cells. Interestingly, the mice that had rejected the clone with high H-2Kb expression received strong anti-tumor immunity for rejection of the parental P1.HTR tumor challenged at the high dose.

Animals↗
PubMed1989

Donor Igh-linked genetic control of allotype-specific antibody response.

Immunogenicity of allogeneic immunoglobulins in mice were studied, measuring the allotype-specific antibody activity by agglutination of allogeneic antibody-coated red blood cells. It was found that the serum from C.B-20 mice (Ighb, BALB/c-congenic) was uniquely immunogenic in BALB/c mice for allotype antibody response. Whereas the C57BL/6 (Ighb) serum was immunogenic only when heat aggregated and/or combined with adjuvant, the ultracentrifugation-deaggregated C.B-20 serum was definitely immunogenic when administered in a moderate dose (100 microliters/mouse). Even more surprising was the fast that very low doses (0.01-0.1 microliter) of soluble C.B-20 serum, but not C57BL/6 serum, down regulated the allotype-specific response effectively. Genetic analysis on congenic mice suggested that the immunogenicity is controlled by donor Igh or Igh-V (Id-C.B) inasmuch as the serum from BALB/c-congenic C.B-20 (Igh-VbCb), but not BALB/c-congenic BAB/14 (Igh-VaCb), mice was active in BALB/c mice in soluble form. Further studies showed that the Id-C.B was dominantly expressed on the immunoglobulins of (BALB/c x C.B-20)F1 and (C56BL/6 X C.B-20)F1 strains, and was originally derived from the C57BL/Ka strain. The major determinant for the antibody production was encoded in Igh-C, but not in Igh-V. It is suggested that Id-C.B controls the allotype-specific antibody response in an unusual manner, possibly acting as a unique determinant activating helper T cells.

Animals↗
PubMed1989

Mode of alloantibody-mediated blockade of allo-sensitization for tumor allograft rejection.

The mode of alloantibody-mediated inhibition of allo-sensitization for tumor allograft rejection was studied. Relatively small amounts of anti-H-2d alloantiserum administered shortly before or after injection of allogeneic spleen cells blocked the allo-sensitization for second-set tumor allograft rejection. In contrast, the alloantiserum injected shortly before inoculation of tumor barely enhanced the tumor growth. The passively administered alloantiserum inhibited the sensitization for allospecific cytotoxic T lymphocyte responses in vitro. Further study revealed that the allo-sensitization could be blocked with antiserum specific against only one of the expressed H-2 antigens on stimulator cells. Correspondingly, H-2Dd-monospecific monoclonal antibody (IgG2a) was effective in inhibiting the sensitization with cells expressing multiple H-2 alloantigens. These results suggest that antibody-mediated inactivation of stimulator cells as a whole is an important mechanism of the allograft enhancement.

Animals↗
PubMed1989

Carbohydrates mediate tissue type-specific membrane activity for Thy-1 alloantibody response.

Thymocyte membrane fragments (TMF) but not brain cell membrane fragments (BMF) show a unique activity for inducing Thy-1 alloantibody response. Treatment of TMF with alpha-mannosidase or endoglycosidase-H greatly diminished this activity but not the serological Thy-1 antigenicity. This suggested that the TMF activity is supported by high mannose type N-linked oligosaccharides on the TMF. On the other hand, treatment with neuraminidase made otherwise silent BMF definitely active for the antibody response and this activity was abolished by further treatment with endoglycosidase-D. This demonstrated that BMF have a latent activity which is mediated by complex type N-linked oligosaccharides normally masked with sialic acids. It was concluded that two types of N-linked oligosaccharides as well as sialic acids mediate at least in part the tissue type-specific membrane activity for Thy-1 alloantibody response.

Animals↗