[Immunosuppressive agents--advances of the developmental studies and the mode of action].
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Animals↗
Biomedical subjects
Y Gunji
Publications and source records attributed to Y Gunji.
Effective and safe use of FK 506: combination treatment with rapamycin or RS-61443 in experimental organ transplantation.
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Animals↗
Pigment color patterns of molluscs as an autonomous process generated by asynchronous automata.
Pigment color patterns of molluscs are studied from the viewpoint of autonomy. Brownian algebra developed by Spencer-Brown (1969) is extensively used for the expression of cellular-automaton rules. When asynchronous updating is introduced for the transition of cellular automata, various kinds of patterns such as traveling waves, kinks, oscillatory local patterns etc. are generated from the same transitional rule. The type of patterns depends more sensitively on the asynchronous updating relationship rather than the transitional rule itself. Therefore, pattern changes in ontogeny can be explained without any changes in transitional rules or reaction processes. It is proposed that asynchronousness is intrinsic to living systems and that recognition of the intrinsic time is essential in understanding living systems.
Animals↗
Fibrin formation inhibits the in vitro cytotoxic activity of human natural and lymphokine-activated killer cells.
The biological significance of the interaction of the haemostatic factors with tumour cells remains unclear. It has been hypothesized that fibrin deposition around tumour cells could help those cells to escape destruction by cytotoxic effector cells. To obtain direct evidence in support of this possibility, the effect of fibrin formation on in vitro cytotoxicity of human natural killer (NK) or lymphokine-activated killer (LAK) cells was investigated by comparing their cytotoxic activity with various human tumour cell lines in the presence of human serum or plasma. The data demonstrate that pre-incubation of human tumour cells with plasma, but not serum, substantially diminished or completely abrogated the cytotoxic effects of these killer cells. This was shown to be due to fibrin formation. The degree of coagulation and the number of radioactive tumour cells trapped in the clot correlated with the extent of inhibition of NK or LAK cytotoxicity. Abrogation of LAK activity was also observed when the effector cells were pre-exposed to plasma or when effector and target cells were simultaneously mixed with plasma and trapped in a fibrin clot. Similar results were obtained when, instead of whole plasma, the cytotoxic effect of LAK and NK cells was studied in the presence of fibrinogen and thrombin. When heparin was added, fibrin formation was prevented and no inhibition of LAK/NK cell cytotoxicity was observed. In studies of the mechanisms of inhibition of LAK cell activity by fibrin, target - effector cell conjugate formation was found to be blocked. When plasma was added post-binding (15-30 min after mixing effector and target cells) although coagulation occurred, no effect on cytotoxicity was observed, supporting the conclusion that fibrin interfered with binding rather than the lytic phase of cytotoxic cell activity. Thus, the present data demonstrate that fibrin deposition around tumour and/or effector cells can protect tumour cells from immune destruction and diminish the efficiency of the cytotoxic LAK/NK cells.
Blood Coagulation↗
[Effect of high dose etoposide, adriamycin, cisplatin (EAP) therapy with autologous bone marrow transplantation in gastric cancer].
A clinical usefulness of high dose EAP therapy with autologous bone marrow transplantation for gastric cancer was investigated. Three patients with advanced gastric cancer (one recurrent and 2 inoperable) with measurable lesions were treated with high dose EAP therapy consisting of VP-16 1200 mg/m2, ADM 80 mg/m2 and CDDP 80-120 mg/m2, and then 1 x 10(7)/kg of cryopreserved autologous bone marrow cells were transfused intravenously. All patients were recovered from aplastic period without any severe complications. Measurable lesions, namely, stenosis of prepyloris lesion, lymph node metastasis and invasion into pancreas in 3 patients with gastric cancer were reduced or diminished. It seemed that high dose EAP therapy with autologous bone marrow transplantation was safe and an useful strategy, especially for advanced gastric cancer.
Adult↗
[Immunotherapy and quality of life].
In order to examine the quality of life with immunotherapy, a survey was conducted on 17 advanced gastric or colon cancer patients receiving LAK immunotherapy and on 10 patients receiving EAP chemotherapy as a control. Performance status of patients at the time of treatment was similar between the groups. Many patients on EAP therapy complained of severe side effects, such as loss of hair, nausea and vomiting, and appetite loss. None of the patients on LAK therapy complained of such effects on the contrary, favorable effects were found. Appetite increased in some patients and tenderness of the liver disappeared in others. As for the continuance of the treatment, two thirds of EAP patients declined, and all LAK patients replied in the affirmative. The data suggest that LAK immunotherapy is better than EAP chemotherapy from the standpoint of the quality of life.
Antineoplastic Combined Chemotherapy Protocols↗
Generation and characterization of purified adherent lymphokine-activated killer cells in mice.
During the incubation of murine spleen, lymph node, or bone marrow cells with IL-2 (1000 U/ml) a small percentage of cells became adherent to the surface of plastic tissue culture flasks. After removal of the non-adherent lymphoid cells, plastic adherent lymphokine-activated killer (LAK) cells could be efficiently expanded in the presence of IL-2. Plastic adherent-derived A-LAK cells were characterized by high rates of proliferation and their cytotoxic activity was more than 10 fold higher than LAK cells generated in the bulk (unfractionated) spleen cell cultures. A-LAK cells could be continuously generated from the non-adherent cell population. Using multiple transfers (every 1 to 2 days) of non-adherent LAK cells into new flasks, new rounds of plastic adherent cells were generated with high expansion capability and high levels of cytotoxic activity. Morphologically, A-LAK cells were large granular lymphocyte and phenotypically expressed markers characteristic of NK cells (asialo GM1+, NK1.1+, Qa5+, Ly-6.2+, Thy-1.2+, but negative for Lyt-2.2 and L3T4). A-LAK cells generated from mice of different strains expressing low and high levels of NK cell activity were equally highly cytotoxic. However, A-LAK cells obtained from nude or beige mice had relatively lower levels of cytotoxicity. Stimulation of NK cell activity by poly I:C or inhibition by in vivo or in vitro treatment with anti-asialo GM1 serum did not affect the generation of A-LAK cells. A-LAK cells derived from spleen or bone marrow of C57BL/6 or nude mice treated with anti-asialo GM1 serum were found to be asialo GM1+ suggesting that A-LAK cell could be generated from the asialo GM1- precursor cells. Expansion of plastic adherent A-LAK cells in the presence of IL-2 could provide large numbers of highly purified cytotoxic A-LAK cells suitable for cancer immunotherapy.
Animals↗
Optimal serum trough levels of FK506 in renal allotransplantation of the beagle dog.
The present study was performed to estimate the optimal serum trough levels of FK506 (FK) for prophylactic use and for the treatment of acute rejection in renal allotransplantation of the beagle dog. The serum trough levels of an immunosuppressive dose of FK 1.0 mg/kg p.o. ranged from 0.1 to 0.4 ng/ml. The data indicate that the effective serum trough level is about 100 times lower than that of cyclosporine, as was already observed in previous in vitro studies. Combining treatment with a nonimmunosuppressive dose of cyclosporine of 2.5 mg/kg could lower the effective trough levels of FK. By the combining treatment, 2 out of 5 renal recipient dogs survived with well-functioning grafts as long as 60 days with the trough levels between 0.04 and 0.07 ng/ml. High-dose 5-day i.m. FK treatment of 0.5 or 1.0 mg/kg was effective in the reversal of acute rejection, with peak serum trough levels during successful rejection therapy ranging between 0.28 and 3.7 ng/ml. Two dogs died of malaise or pneumonia with peak trough levels of 2.25 and 2.78 ng/ml. Among the wide range of the effective trough levels for successful acute rejection therapy, those above 2.0 ng/ml seem to be toxic in some renal-transplanted dogs.
Administration, Oral↗
Effects of combination treatment with FK506 and cyclosporine on survival time and vascular changes in renal-allograft-recipient dogs.
In our previous experiments studying the effects of FK506 on renal allografting in the dog, we encountered two major problems. One problem was anorexia and the other problem was vascular changes mainly in the recipient heart. Anorexia was generally dose dependent, but the vascular changes were seen to be more prominent at lower doses rather than at higher immunosuppressive doses. The present study was undertaken to study these two problems. A nonanorexic, vascular change-related, nonimmunosuppressive dose of FK506 was combined with a low dose of cyclosporine or prednisolone in beagle dogs after renal allografting. Treatment with either FK506 alone at a dose of 0.32 mg/kg or cyclosporine alone at 2.5 mg/kg was not effective in prolonging renal recipient survival. The recipient dogs died of rejection, and a variety of vascular changes were observed in the hearts of both groups. Combined treatment with FK506 and cyclosporine at these same doses resulted in statistically significant prolongation of the survival time of the renal recipient (P less than 0.01), and histologic studies showed that the frequency and severity of the vascular changes were suppressed in the recipient receiving the combined treatment. The combination of FK506 and prednisolone at 0.5 mg/kg was not effective in prolonging survival. Furthermore, the extent of vascular changes was similar to those found in recipients receiving FK506 alone. The data suggest that combined treatment with low doses of both FK506 and cyclosporine acted synergistically in prolonging canine renal allografts and that the vascular changes frequently seen at low doses of FK506 were reduced by additional immunosuppression with a low dose of cyclosporine.
Animals↗
Comparative studies on the immunosuppressive activity of FK506, 15-deoxyspergualin, and cyclosporine.
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Animals↗
[Over two years survival of intra-arterial infusion chemotherapy in gastric cancer with liver metastases].
Between 1977 and April in 1989, long-term survivors (over two years) by intra-arterial infusion chemotherapy in gastric cancer patients with liver metastases were examined. The materials were 5 patients (4 synchronous, 1 metachronous metastases) among 21 P0H (+) gastric cancers. The extent of liver metastases shows 1 H1 and 4 H2. Reduction surgery was performed in 4 H2 patients (2 S2 + 3, 1 S4, 1 S6) and postoperative intra-arterial infusion chemotherapy via the catheter in the common hepatic artery was done to control the residual liver metastases. Continuous intra-arterial infusion chemotherapy with the regimen of FML (5-FU, MMC, Lentinan) revealed 100% response rate (3 CR, 1 PR). In a patient with metachronous metastases, PR was obtained with MA (MMC, ADM) + one-shot intra-arterial infusion of LAK cells. Among 5 patients, one with synchronous metastases has survived 35 months, followed by a patient who died after 32 months and two patients who died after 27 months. A patient with metachronous metastases has survived for 24 months.
Aged↗
Role of fibrin coagulation in protection of murine tumor cells from destruction by cytotoxic cells.
We have previously proposed that fibrin deposition on tumor cells during their migration in the blood could protect them from elimination by natural killer (NK) or other cytotoxic cells. Anticoagulant drugs could prevent fibrin coagulation and increase the efficiency of cytotoxic effector cells in tumor cell elimination. To further investigate the protective roles of fibrin, we studied in vitro the susceptibility of various murine tumor cells to the cytotoxic activity of NK or lymphokine activated killer (LAK) cells in the presence of murine plasma or serum. In the first set of experiments, tumor cells were incubated with plasma (at dilutions of 1:20-1:160) for 30 min before effector cells were added. Similarly, effector cells were first incubated with plasma before mixing with radiolabeled target cells for cytotoxicity assay. In some experiments target and effector cells and plasma were mixed simultaneously. The cytotoxic activity of both NK and LAK cells was inhibited if coagulation occurred around tumor-target or effector cells. Tumor cells were also protected when both target and effector cells were simultaneously mixed and trapped in the fibrin clot. Inhibition of the cytotoxic activity of effector cells against tumor cells was positively correlated with the level of fibrin clot formation. When the larger clot was formed and more radiolabeled tumor cells were trapped in the clot, the higher level of inhibition of cytotoxicity was observed. In contrast, serum did not affect the cytotoxic activity of NK or LAK cells. To exclude possible non-coagulation-related effects of plasma on LAK cells, a cytotoxicity series of experiments was performed using purified fibrinogen and thrombin. When fibrinogen and thrombin were preincubated with tumor cells or LAK cells or all components were admixed simultaneously, substantial protection of tumor cells from destruction by LAK cells was also observed. However, when heparin was added, fibrin coagulation was prevented and cytotoxic activity of LAK cells was restored. Inhibition of LAK cytotoxicity and protection of tumor cells by fibrin coagulation were mostly due to the prevention of tumor-effector cell conjugate formation. Adding plasma at postbinding time periods (15-30 min after mixing effector and target cells) did not affect the ability of LAK cells to kill tumor cells confirming that fibrin coagulation influenced the binding rather than the lytic phase of cytotoxic cell activity.
Animals↗
H-2 antigen expression and sensitivity of BL6 melanoma cells to natural killer cell cytotoxicity.
The sensitivity of H-2b-high and H-2b-low variants of BL6 melanoma to the cytotoxic action of NK and lymphokine-activated killer cells was investigated. BL6 mouse melanoma cells lack detectable H-2Kb and had low levels of expression of H-2Db Ag. The BL6T2 variant cells, obtained after treatment of BL6 cells with mutagen N-methyl-N-nitro-N'-nitro-soguanidine, had relatively high levels of expression of class I H-2b Ag. Poly(I:C)-stimulated spleen cells of nude mice were highly cytotoxic for BL6T2, whereas H-2b-low BL6 cells were less sensitive to NK activity in an 18-h 51Cr-release assay. Similar results were obtained after 4-h incubation of radio-labeled tumor cells with IL-2-activated effector cells. In contrast, both lines were equally sensitive to lysis by purified granules derived from rat large granular lymphocytes (LGL) or by macrophages. By using various clones selected from BL6 or BL6T2 cells, it was found that BL6 or BL6T2 clones with low H-2b Ag expression were less sensitive to lysis by NK cells than H-2b-high clones. After IFN treatment of either BL6 or BL6T2, the target cells became more resistant to lysis by either NK cells or by purified LGL granules. IFN-treated BL6 cells had substantially increased expression of H-2b Ag and in this respect became similar to untreated BL6T2. However, IFN-treated BL6 cells were more resistant than BL6T2 cells to lysis by NK cells and LGL granules, suggesting that augmentation of H-2b Ag expression and NK resistance could be two independent IFN-induced effects. With a cold target inhibition assay, it was found that BL6T2 or its H-2 positive clones were highly competitive and inhibited the cytotoxic activity of NK and lymphokine-activated killer cells against radiolabeled YAC-1 and BL6T2, whereas BL6 cells or H-2-negative clones of BL6T2 and BL6 lines showed poor competitive ability. Thus, our data indicate that the NK resistance of H-2-low BL6 cells may be due to a paucity of NK recognizable determinants. N-Methyl-N-nitro-N'-nitroguanidine treatment of BL6 melanoma cells was associated with an increase in class I H-2b Ag expression and NK sensitivity, suggesting the involvement of class I MHC Ag in the sensitivity of tumor cells to NK cell-mediated cytotoxicity.
Animals↗
Neonatal hyperlactacidemia and hypoglycemia caused by delayed maturation of fructose-1,6-diphosphatase activity.
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Follow-Up Studies↗
Interaction of tumor cells and immune system in the metastatic process.
The metastatic process is rather complicated and relatively inefficient. Millions of tumor cells are constantly shedding from the primary tumor into the blood stream, but very few of them are able to form metastatic tumors in the different organs or tissues of the host. It is widely accepted that metastatic cells have to possess a complex array of various properties that allow them to complete the metastatic cascade. The realization of the metastatic potential largely depends on the ability of tumor cells to evade host defense mechanisms. The potential role of specific and nonspecific immune mechanisms in the control of metastatic spread and growth is the subject of the present review. A better understanding of the mechanisms of antimetastatic defense is of prime importance for development of efficient immunotherapeutic methods for the treatment and eradication of disseminated tumor metastases.
Animals↗
Studies of the effects of FK506 on renal allografting in the beagle dog.
The immunosuppressive activities of a newly discovered macrolide extracted from Streptomyces tsukubaensis, FK506, were examined using 38 renal allografts in the beagle dog. The median survival time was 15.5 days in dogs without treatment, 61 days with a dose of 0.08 mg/kg/day and 176 days with a dose of 0.16 mg/kg/day of intramuscularly administered FK506. Prolongation of survival was statistically significant when compared with controls (P = 0.02, 0.0044, respectively). None of 6 recipient dogs receiving the agent at a dose of 0.16 mg/kg/day encountered rejection during the treatment course. Three of them survived over 200 days. Oral administration of FK506 at a dose of 0.32 mg/kg/day did not prolong the median survival time (20.5 days) compared with the placebo treated control (16.5 days), but oral treatment with 1.0 mg/kg/day resulted in all of the recipient dogs surviving over 130 days. Histological studies of 7 kidney graft biopsy specimens of the dogs surviving over 3 months revealed no cell infiltration or only some degree of reversible interstitial cell infiltration, but vascular and glomerular changes were not observed in any of the specimens. Irregularity of nuclear shape and cytoplasmic vacuolation of the pars recta of the proximal tubules were observed in one dog each. Liver biopsy specimens showed no consistent evidence of hepatocellular damage. Three dogs died of intussusception 2-3 weeks posttransplant. The dogs treated intramuscularly with 0.32 mg/kg/day suffered from anorexia. Two dogs receiving oral treatment at a dose of 1.0 mg/kg developed papilloma of the skin around day 60, but the tumors disappeared by day 120. We conclude that FK506 is a powerful immunosuppressant in the dog with tolerable side effects.
Administration, Oral↗
Syngeneic monoclonal anti-melanoma antibody that inhibits experimental lung metastasis of B16 melanoma.
An objective method to evaluate experimental lung metastasis of murine melanoma has been established by sandwich radioimmunoassay using monoclonal anti-melanoma antibody (M2590). The assay system quantitatively detected melanoma antigens metastasized in the lung. The data obtained by radioimmunoassay were consistent with those obtained by the usual colony-counting method. By the use of these detection systems for lung metastasis, we found that only one particular syngeneic monoclonal antibody (M562) recognizing a proteinaceous determinant on melanoma antigen significantly inhibited experimental lung metastasis of melanoma cells (1/7-1/10 of controls), whereas other syngeneic monoclonal antibodies with the same specificity and the same immunoglobulin class or control antibody did not. It is therefore strongly suggested that the molecule recognized by M562 antibody plays an important role in lung metastasis of melanoma cells.
Animals↗
Role of IA-positive cells in the beneficial effect of donor blood transfusion and induction of suppressor cells in cardiac allotransplantation of rats.
An attempt was made to reveal the role of Ia-positive cells in the beneficial effect of pretransplant donor-specific blood transfusion (DST) and induction of suppressor cells in the cardiac allotransplantation of rats. Mean graft survival time (MST) of F344 (RT1 1v1) hearts transplanted in WKA (RT1k) rats was 6.5 +/- 0.8 days. Pretreatment of recipients with 1 ml DST 10 days before grafting prolonged it to 56.5 +/- 38.1 days. Plasma or erythrocytes did not prolong MST at all, whereas pretreatment with 1 X 10(7) lymphocytes prolonged MST significantly. B enriched cells separated on a nylon-wool column prolonged MST, but T-enriched cells did not. Treatment of lymphocytes with interspecies crossreactive monoclonal anti-Ia antibody and complement eliminated the ability of lymphocytes to prolong MST, suggesting an important role of Ia-positive cells in the beneficial effect of DST. The role of Ia-positive cells in prolonging graft survival, was analyzed by a cell and serum transfer experiment. MST of F344 heart allografts transplanted in sublethally irradiated (500 rads) WKA rats was 17.4 +/- 4.0 days. MSTs of allografts in rats irradiated and treated with serum or spleen cells of blood-conditioned rats were 23.2 +/- 1.6 (P less than 0.05) and 5.2 +/- 0.7 (NS) days, respectively. On the other hand, MSTs of the grafts in rats irradiated and treated with serum or spleen cells harvested from rats that had accepted grafts for 30 days were 18.7 +/- 1.9 (NS) and 63.8 +/- 29.9 (P less than 0.01) days, respectively. The results indicate that the initial role of a serum factor in prolonging graft survival induced by DST containing Ia-positive cells was followed by activating suppressor cells by the presence of the allograft.
Animals↗