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T Ebina

Publications and source records attributed to T Ebina.

At least 91 records · Page 5Linked to original sources
PubMed1986

Characterization of monoclonal antibodies against human rotavirus hemagglutinin.

Three monoclonal antibodies capable of specifically inhibiting hemagglutination of human rotavirus were produced. Their hemagglutination inhibition (HI) activity was specific to the homologous strain (KUN) used for immunization. The monoclonal antibodies with HI activity were highly effective in neutralizing the infectivity of the KUN strain. These antibodies reacted with Vp80, and 80,000 molecular weight (MW) protein present in the viral outer shell. It was confirmed by immunoblotting assay with the monoclonal antibodies that the antigenic site of human rotavirus hemagglutinin (HA) resides on Vp80 and on its smaller trypsin cleavage products Vp30 (MW 30,000) and Vp24 (MW 24,000). Immunofluorescence studies using the antibodies revealed that the HA antigen of the KUN strain developed at the final stage of virus maturation.

Animals↗
PubMed1986

Inhibition of murine L cell interferon action by heparin.

Heparin added together with murine L cell interferon inhibited the development of antiviral activity in mouse L cells. When added after interferon treatment, heparin had no effect on antiviral activity. There was also no inhibition of interferon action in L cells treated with heparin before addition of interferon. On the other hand, heparin did not inhibit antiviral activities of human interferon alpha and beta. Since murine L cell interferon, but not human interferon alpha and beta, binds to a heparin affinity column and can be eluted with a solution of high salt, it is presumed that murine L cell interferon and heparin must interact with each other. The apparent interaction of heparin with murine L cell interferon was prevented by protamine, a drug that neutralizes heparin. Dextran sulfate inhibited murine L cell interferon action, but dextran and chondroitin sulfate A did not. These results suggests that heparin inhibited murine L cell interferon action by the binding via sulfate groups on its molecules. Heparin also inhibited antiviral activity of murine L cell interferon in mice infected with herpes simplex virus (+GC Miyama strain).

Animals↗
PubMed1986

Inhibition of intravascular mouse melanoma dissemination by recombinant human interferon alpha A/D.

The effects of pure recombinant human interferon alpha A/D (IFN alpha A/D) on natural killer (NK) activity and the experimental lung metastasis of B16-F10 melanoma were studied. Treatment of C57BL/6 mice with IFN alpha A/D augmented splenic NK activity and also inhibited the experimental lung metastasis of B16-F10 melanoma in a dose-dependent manner. The augmentation of NK activity and the inhibition of experimental lung metastasis by IFN alpha A/D were completely abolished in anti-asialo GM1-pretreated mice. These results suggested that the effector cells which inhibited melanoma metastasis in the present system were mainly NK cells, and that it was by activating NK cells that IFN alpha A/D had its effect. We next studied the timing of IFN alpha A/D administration for the most effective prevention of melanoma metastasis. The inhibitory effect of IFN alpha A/D was most pronounced when it was given 12 hr before or at the same time as melanoma inoculation. This suggested that melanoma cells were susceptible to NK cells only for a short period of time after intravascular invasion.

Animals↗
PubMed1986

Antitumor effect of recombinant human interferon alpha A/D on Meth-A sarcoma in mice.

Recombinant human interferon alpha A/D (IFN alpha A/D) is known to be as active on murine cells as on human cells. We studied the antitumor effect of pure IFN alpha A/D on Meth-A sarcoma subcutaneously transplanted into female syngeneic BALB/c mice. When administered systematically (intraperitoneally), IFN alpha A/D was only marginally (but significantly, P less than 0.05) effective in inhibiting tumor growth. With intralesional injection, however, IFN alpha A/D strongly suppressed the growth of Meth-A sarcoma, even leading to complete tumor regression and to subsequent immunity to Meth-A sarcoma cells in the host mice when the treatment was started early after tumor transplantation and with a high IFN alpha A/D dose. We also found that treatment of mice with IFN alpha A/D increased the level of serum alpha 1-acid glycoprotein, one of the acute-phase proteins.

Animals↗
PubMed1986

Antitumor effect of a synthetic cord factor, 6,6'-di-O-decanoyl-alpha,alpha-trehalose (SS554), in mice.

The antitumor effect on Meth-A fibrosarcoma in BALB/c mice of a synthetic cord factor, 6,6'-di-O-decanoyl-alpha,alpha-trehalose (designated as SS554), was examined. Only intratumoral injection had a curative effect; subcutaneous, per oral, or intravenous routes had no such effect. The co-presence of an oily vehicle has been shown to be necessary for antitumor activity of a natural cord factor. When SS554 was examined in suspensions of sesame oil, squalane, squalene or sesame oil and water emulsion, a 60% cure rate was achieved. However, no such effect was obtained with a suspension in Tween-PBS or a solution. It should also be noted that sequential but independent administrations of SS554 and oil were found to be as effective as the simultaneous administration of oil and SS554 in emulsion form. In the case of the emulsion, the amount of sesame oil necessary was over 10%, or 0.01 ml in absolute terms. Cures were obtained in a dose-dependent manner by injection of SS554 in amounts in excess of 1 mg. The effect of the time of administration was also examined; the best result was obtained when intratumoral injection was done on day 3 after tumor implantation. Mice cured by SS554 exhibited growth inhibition and rejection of rechallenged Meth-A cells. However, this immunity was specific; it did not extend to a rechallenge with RLmale-1 leukemia cells.

Animals↗
PubMed1986

Antimetastatic effect of biological response modifiers in the "double grafted tumor system".

The antimetastatic effect of biological response modifiers (BRM) in a new experimental mouse model was studied. Intratumoral administration of BRMs (PSK, OK-432, interferon alpha A/D) strongly inhibited the growth of Meth-A solid tumors in male BALB/c mice and led to a complete regression of tumors and resistance to reinoculated tumors. Subsequently, the antimetastatic effect of BRMs was examined in the "double grafted tumor system," in which mice first received simultaneous intradermal inoculations of Meth-A in the right (10(6) cells) and left (2 X 10(5) cells) flanks and were then injected with BRMs in the right tumor on day 3. PSK and interferon (IFN) significantly inhibited the growth of the left (non-treated) tumor. This finding suggests that intratumoral BRM immunotherapy in one region has an effect on tumor growth in another region. Immunized spleen cells were taken from mice which had been cured by the intratumoral administration of BRMs and had rejected reinoculated tumors. One hour after intravenous injection of cyclophosphamide (2 mg/mouse), immunized spleen cells (2 X 10(7) cells/mouse) were injected into the Meth-A tumor on day 3. Adoptive transfers of PSK and IFN immunized spleen cells caused the complete regression of Meth-A tumors. These results suggest that the intratumoral administration of BRMs might induce cytotoxic cells in the left non-treated tumor of the "double grafted tumor system" and bring about the regression of metastatic tumors.

Adjuvants, Immunologic↗
PubMed1986

[Antitumor effect of a synthetic cord factor, 6,6'-di-O-decanoyl-alpha, alpha-trehalose (SS 554) in mice].

The antitumor effect of a synthetic cord factor (6, 6'-Di-O-decanoyl-alpha, alpha-trehalose) (SS 554) on the growth of Meth-A fibrosarcoma in BALB/c mice was examined. With regard to administration routes, only intratumoral (i.t.) injection showed a curative effect; subcutaneous (s.c.), per oral (p.o.) or intravenous (i.v.) routes has no such effect. To show the antitumor effect of known natural and synthetic cord factors, the co-presence of oily vehicles has been shown to be necessary. Accordingly, compound SS 554 examined in suspensions of sesame oil, squalane (SQA), squalene (SQE) or sesame oil and water emulsion had a curative effect with a 60% survival rate. However, no such effect was obtained with a suspension in PBS or in HCO-60 solution. In this regard, it should be noted that sequential but independent administration of SS 554 and oil was found to be equally as effective as simultaneous administration of oil with SS 554. Thus the effect of the oil should be reconsidered through an examination of the sequential appearance of effector cells. In the case of sesame oil, the amount of oil necessary was over 10%, or 0.01 mg absolutely. When the dose effect of SS 554 was examined in the presence of 10% sesame oil, doses over 1 mg exhibited a dose dependent curative effect. In tumor-bearing mice, the effect of the time of administration was also examined; the best result was obtained when intratumor injection was performed on day 3 after tumor implantation. Mice that recovered after SS 554 treatment exhibited growth inhibition and rejection of rechallenged Meth-A cells. However, this immunity was specific as it did not extend to a rechallenge with RL male-1 leukemia cells.

Animals↗
PubMed1986

Role of natural killer cells in intraocular melanoma metastasis.

The authors studied the role of natural killer (NK) cells in spontaneous metastasis of murine intraocular melanoma by transplanting murine B16 melanoma cells into the anterior chamber of the eye in syngeneic C57BL/6 mice and determining the number of metastatic lung tumor colonies after 40 days. Depletion of NK activity by anti-asialo GM1 serum dramatically enhanced metastasis and augmentation of NK activity by interferon inhibited it. The strong correlation between host NK activity and intraocular melanoma metastasis indicated that NK cells have an important role in spontaneous metastasis of intraocular melanoma.

Animals↗
PubMed1985

Prevention of rotavirus infection by oral administration of cow colostrum containing antihumanrotavirus antibody.

After immunizing 8-month pregnant Holstein cows with human rotavirus, Wa strain, cow colostrum containing neutralizing antibody to human rotavirus, designated as Rota colostrum, was obtained. After randomly grouping 13 infants from a single orphanage, 6 infants received 20 ml of Rota colostrum every morning and 7 control infants received 20 ml of market milk. One month later, rotavirus associated diarrhea was observed in 6 of the 7 infants given milk and 1 out of the 6 infants given Rota colostrum. Orally administered Rota colostrum significantly protected infants from diarrhea caused by rotavirus (P less than 0.05). Two out of 5 Rota colostrum recipients who were free from diarrhea showed rises in complement fixation (CF) antibody titer after the rotavirus infection epidemic. Thus, Rota colostrum prevented the outbreak of diarrhea but did not prevent immunological responses to natural rotavirus infection. In the therapeutic trial Rota colostrum had no effect on duration of diarrhea, bowel movements or virus shedding in stool. However, there were no side-effects of Rota colostrum.

Administration, Oral↗
PubMed1985

Induction of interferon and activation of NK cells and macrophages in mice by oral administration of Ge-132, an organic germanium compound.

After oral administration of an organic germanium compound, Ge-132 (300 mg/kg), a significant level of interferon (IFN) activity was detected in the sera of mice at 20 hr and it reached a maximum of 320 U/ml at 24 hr. This IFN activity was lost after heat- or acid-treatment, suggesting that the induced IFN is of gamma-nature. The molecular weight of this IFN was estimated to be 50,000 daltons by gel filtration. The NK activity of spleen cells was increased 24 hr after the oral administration of Ge-132, and cytotoxic macrophages were induced in the peritoneal cavity by 48 hr. In the mice receiving an intraperitoneal (ip) injection of trypan blue or carrageenan 2 days before oral administration of Ge-132, neither induction of IFN nor augmentation of NK activity occurred, and X-ray irradiation of mice also rendered the mice incapable of producing IFN, all indicating that both macrophages and lymphocytes are required for this IFN induction. Both NK and cytotoxic macrophages appeared 18 hr after ip administration of the induced IFN with a titer as low as 20 U/ml. These facts suggest that both the augmentation of NK activity and activation of macrophages in mice after oral administration of Ge-132 are mediated by the induced IFN.

Administration, Oral↗
PubMed1985

[Antitumor effect of human interferon-alpha A/D in mice (II). Activation of natural killer cells and suppression of metastasis].

Human recombinant interferon-alpha A/D (IFN-alpha A/D) is known to be effective on murine cells. We studied the in vivo effects of pure IFN-alpha A/D on murine splenic natural killer (NK) activity and experimentally induced pulmonary metastasis of B16-F10 melanoma. Intraperitoneal injection of IFN-alpha A/D augmented splenic NK activity, and suppressed melanoma metastasis. This suppression was abrogated by pretreatment of mice with anti-asialo GMl, but not with silica or carrageenan, showing that the effect of IFN-alpha A/D was dependent on NK cells. The suppression was strongest when IFN-alpha A/D treatment was given 12 hrs before or at the same time as tumor injection, showing that NK cells are most effective in the early phase of melanoma metastasis.

Animals↗
PubMed1985

[Antitumor effect of OK-432 (3)--mechanisms of tumor growth inhibition by OK-432 induced activated macrophages].

Spleen cells and peritoneal exudate cells obtained from BALB/c mice which had received an i.p. injection of 0.1 mg of OK-432 4 days previous to sacrifice, were examined by Winn's neutralization assay for their antitumor activity against Meth-A sarcoma cells in BALB/c mice. Both of the cell preparations clearly inhibited the growth of admixed Meth-A cells, but when these same cell populations were treated on a Sephadex G-10 column, the effector activity seen in Winn's assay disappeared. The effector cells responsible for tumor inhibition were therefore considered to be cytotoxic macrophages. However, the inhibitory effect of these cytotoxic macrophages in Winn's assay was not evident in either X ray (300 rad)-irradiated BALB/c mice or in nu/nu BALB/c mice. These results indicate that the antitumor activity of cytotoxic macrophages is associated with a sequential immune mechanism in which T cells may play an important role.

Animals↗
PubMed1985

[Antitumor effect of human recombinant interferon-alpha A/D in mice(I): Comparison between systemic and lesional treatment of meth-A sarcoma in BALB/c mice].

Human recombinant interferon-alpha A/D (IFN-alpha A/D) is known to be as active on murine cells as on human cells. We studied the antitumor effect of pure IFN-alpha A/D on Meth-A sarcoma cells in vivo. When administered systemically (intraperitoneally), IFN-alpha A/D (total dosage: 7 X 10(5) units/mouse) was only marginally but significantly (p less than 0.05) effective in reducing the growth of Meth-A sarcoma cells transplanted subcutaneously into syngeneic BALB/c mice. By lesional (intra-tumor) administration (total dosage: 5 X 10(4) to 5 X 10(5) units/mouse), however, IFN-alpha A/D strongly inhibited the growth of Meth-A sarcoma cells and even led to a complete regression of tumor growth and subsequent immunity to Meth-A sarcoma cells in the host animals when treatment was started early after transplantation and at a high dose. Indomethacin or cyclophosphamide administered intraperitoneally at a dose at which, although not directly effective against tumor growth, both were expected to stimulate the host immune system by inhibiting suppressor macrophage function or suppressor T cells, respectively, showed neither enhancing nor suppressing effect on the above mentioned strong antitumor effect of locally administered IFN-alpha A/D.

Animals↗
PubMed1985

[Antitumor effect in mice of an organic germanium compound (Ge-132) when different administration methods are used].

The antitumor effect of an organic germanium compound, carboxyethylgermanium sesquioxide (Ge-132), was examined in mice using two systems: one, the ascitic form of Ehrlich carcinoma in DDI mice, and the other, the solid form of Meth-A fibrosarcoma in BALB/c mice. In the mice with Ehrlich ascitic tumors, a remarkable prolongation in life span was observed after intraperitoneal (i.p.) or per oral (p.o.) administration of Ge-132 (300 mg/kg), but not after intravenous (i.v.) injection of the same compound. Following i.p. or p.o. administration, cytotoxic macrophages (Mø) were induced in the peritoneal cavity after 48 h. although this was not the case after i.v. injections. When the in vivo effect of these in vitro active Mø was examined after adoptive transfer to mice bearing Ehrlich ascitic tumor cells, a significant antitumor effect was noted. In the mice bearing solid Meth-A tumors, i.v. injections of Ge-132 (100 mg/kg) were found to inhibit tumor growth remarkably, although i.p. and p.o. administrations did not have the same result. This inhibitory effect of Ge-132 by i.v. administration was explained by the continued augmentation of NK activity in peripheral blood, which was followed by the induction of specific killer cells appearing in the spleen. When the mice which had recovered from Meth-A tumor growth, following i.v. injections of Ge-132, were challenged with the same tumor on day 30, all mice were able to tolerate the challenge, but not a challenge of RL male 1 tumor cells. These observations may indicate that the differing antitumor effects of Ge-132 produced when different administration methods are used can be explained by the variation in effector cells induced by such different administration routes.

Administration, Oral↗