[Basic study of chemo-embolization of the liver using hydroxyapatite granules]

The purpose of this study was to elucidate the availability of hydroxyapatite (HAp) granules as a chemoembolic agent in chemo embolization therapy. A mixture of adriamycin (ADM) and an embolic agent (HAp, Lipiodol) was injected via hepatic artery in normal Wistar rats. Then the concentration of ADM in the liver serum transaminase level were measured serially. The remaining ADM in the liver was higher in groups with HAp granules than the others. The serum transaminase, however, were lower in the HAp groups. There are some advantages of HAp using as a chemo embolic agent. (1) HAp is a physiological biomaterial and seem to be safe for human. (2) HAp granules injected into the liver are easily detectable by X ray and ultrasonography. (3) HAp granules have a large surface area and this characteristic is suitable for a carrier of drugs. It is concluded that HAp granules have some necessary prerequisites for a chemo embolic agent and the application to clinical practice may be expected.

Effect of immunization and potassium iodide on polymorphonuclear leukocyte chemiluminescence in experimental murine sporotrichosis

This study was undertaken to examine the effects of immunization with Sporothrix schenckii and oral potassium iodide (KJ) administration on the chemiluminescence (CL) response of mouse polymorphonuclear leukocytes (PMNs) in experimental murine sporotrichosis. When N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP) particles were used as foreign bodies to be phagocytosed, the time to the peak CL response of the PMNs in an immunized group was shortened in comparison with a non-immunized control group, and the CL intensity was found to be prolonged. Whereas administration of KJ resulted in a reduction of the CL intensity in non-immunized mice, in immunized mice it caused a rise in CL intensity. When the foreign bodies used as targets for phagocytosis were Sp. schenckii, changes similar to the above occurred, but CL production was reduced.

[Effects of UFT on experimental liver metastases and on the immunologic capacity of the hosts]

An experimental model is introduced for the study on liver metastasis using intrasplenically injected EL-4 and Lewis lung tumor (LLT) cells. The inhibitory effects of UFT, FT and 5-FU on the frequencies of metastatic foci in the liver were compared. All drugs showed inhibitory effect on the frequencies of liver metastasis. However, a high dose of UFT suppressed strongly the frequencies of liver metastasis. In order to compare the immunosuppressive activity of UFT with that of FT and 5-FU at the dose to give 50% inhibition of liver metastasis (MED50), we determined the MED50 values of UFT, FT or 5-FU against liver metastasis of EL-4 and LLT cells. FT and 5-FU were suppressed strongly the humoral response against SRBC, the delayed hypersensitivity against picryl chloride and the phagocytic activity. UFT had no inhibitory effect on immune responses.

Inhibition of tumor growth by dairy products

Effects of dairy products (cheeses and yoghurt) on growth of transplanted murine tumors were examined in various tumor-host combinations. Suppression of tumor growth was observed in proportion to the duration of feeding. Peripheral lymph-node (LN) cells of mice fed dairy products showed an increment in the fluorescence intensity of Thy-1.2+ cells in FACS analysis. These cells showed an augmented PHA response and a remarkable antitumor effect in tumor neutralization test (Winn's assay) compared to control lymphocytes. These results suggest that dairy products enhance the activity of peripheral LN cells to suppress the tumor growth. Moreover, serum transfer from cheese fed mice revealed the protective effects against tumors, while that from yoghurt fed mice did not show such an effect. In the former mice, serum iron level was increased compared to control levels but antibody response to sheep erythrocytes (SRBC) was not augmented. From these results, we propose a hypothesis that lymphocytes may be activated by transferable serum factors such as iron-saturated transferrin and suppression of tumor growth caused by the effector-target interaction which is mediated by effector-associated transferrin in the case of cheese fed mice. In yoghurt fed mice another mechanism is suspected because of the low level of serum iron.

A rapid method for the isolation of functional human T lymphocytes using hydroxyapatite column fractionation

Passage of peripheral blood lymphocytes through a column of hydroxyapatite resulted in a 7-20-fold depletion of immunoglobulin-bearing cells, a 20-fold depletion of monocytes, and a 1.3-fold enrichment of T cells. The effluent population was virtually devoid of B lymphocyte precursors and monocytes, whereas helper cell and suppressor cell populations remained intact. This method will facilitate the rapid preparation of T-enriched cell populations.

Effect of a high-fat diet on resistance to Listeria monocytogenes

Effects of a high-fat diet on macrophage (M phi) functions were investigated. Eight-week-old ddN mice were fed a high-fat diet and carbon clearance was tested. Remarkable suppression of phagocytic activity (K16) was observed in mice fed such a diet for 1 or 2 weeks. Resistance against Listeria monocytogenes inoculated intravenously (iv) with a lethal, a sublethal, or a non-pathogenic dose was observed in the liver of mice fed a high-fat diet. When mice were infected with a lethal dose of bacteria, the number of listeria increased progressively in the liver to kill both control and a high-fat diet fed mice by day 4. The number of listeria revealed no significant difference between the group in the case of low dose inoculation. High-fat diet fed mice given a sublethal dose of bacteria showed a rise in the number of viable bacteria during the first 3 days after infection while a decline in the number of bacteria was observed in control mice during such a period. Suppression of M phi activity induced by a high-fat diet may account for the reduced resistance.

Enhancement of host defence by Y-19995 (2,4'-bis(1-methyl-2-dimethyl-aminoethoxyl)-3-benzoylpyridine dimaleate), a novel synthetic compound. II. Activation of phagocytic cell functions

A novel synthetic compound, Y-19995 potentiated phagocytic activity of rat or mouse peritoneal polymorphonuclear leukocytes in vitro or in vivo, respectively. The agent enhanced NBT reducing capacities of rat and guinea pig polymorphonuclear leukocytes in the peripheral blood ex vivo. Y-19995 restored from phagocytic activity of mouse peritoneal macrophages suppressed by the treatment with prednisolone ex vivo. In addition, IL-1 production by mouse macrophages was augmented by culturing with the agent in vitro. Furthermore, Y-19995 potentiated both phagocytic activity and NBT reducing capacity of human peripheral polymorphonuclear leukocytes in vitro. These results suggested that the activation of phagocytic cell functions by Y-19995 contributed to the enhancement of host defence in immunocompromised hosts.

Involution of the thymus in tumor-bearing mice and its restoration by PSK. II. Mechanism of the involution and its restoration

In C3H/He mice, the weight and cell number of the thymus were reduced and the size distribution (scatter profile measured by flow cytometer) of the thymus cells was changed 1 week after subcutaneous inoculation of X5563 plasmacytoma. This involution and change were prevented by intraperitoneal or oral administration of PSK. We examined the mechanism of this involution and change in thymus and the effect of PSK on them. In X5563-bearing C3H/He mice, 3H-thymidine incorporation into the thymus was reduced compared with that in control mice, as evaluated not only per organ but also per 1 mg of thymus tissue. Such reduction was inhibited by PSK. The substance (IS substance) which possessed a suppressive activity against mitogen induced lymphocyte proliferation, was partially purified from the ascites of X5563-bearing mice by the combination of ammonium sulfate precipitation and Sephacryl S-200 chromatography. IS substance was demonstrated to suppress the antibody response and delayed type foot-pad response against sheep red blood cells in mice. The reduction of weight and cell number and the change of scatter profile in thymus were caused by injection of this substance even in tumor-free mice. The restorative effects of PSK were observed also in IS substance injected mice. These results suggested that the various changes in the thymus observed in tumor-bearing mice might be attributable to the suppression of cell proliferation in the thymus, that such suppression was caused at least partly by an immunosuppressive substance which possessed inhibitory activity against lymphocyte proliferation, and that PSK had an antagonistic activity against such a substance so as to restore the function of the thymus in tumor-bearing hosts.

Treatment of autoimmune MRL/Mp-lpr/lpr mice with cholera toxin

The autoimmune manifestations of MRL/Mp-lpr/lpr(MRL/l), a murine model of systemic lupus erythematosus (SLE), were alleviated by administering 1 microgram cholera toxin (CT) every 14 days. The beneficial effects were: (i) significant prolongation of survival time, (ii) prevention of lymphadenopathy, (iii) improvement of T cell mitogenic responses and suppression of a B cell mitogenic response, (iv) decrease in serum anti-DNA and anti-Sm antibodies, (v) increase in IL-2 production by stimulation of spleen cells with concanavalin A (Con A). It is possible that CT may be effective for treatment of murine lupus nephritis by modulating polyclonal lymphocyte activation. This type of immunomodulation may pave the way toward treatment of lupus and other autoimmune diseases.

Oral immunization in adult mice to live and heat-killed Vibrio cholerae

Effects of systemic and intestinal local immune responses in mice fed ad libitum and forcedly with live or heat-killed Vibrio cholerae on the elimination of vibrios from the intestine were investigated. In mice fed with live vibrios, ad libitum feeding could induce potential delayed-type hypersensitivity and rapid production of vibriocidal antibody in the serum whereas forcedly feeding suppressed the delayed-type hypersensitivity and retarded the antibody production. In contrast, when killed microorganisms were used as antigens, significant delayed-type hypersensitivity and rapid response of vibriocidal antibody were induced in forcedly fed mice although ad libitum feeding suppressed the induction of the delayed-type hypersensitivity and retarded the production of vibriocidal antibody. The elimination of vibrios from the intestine of mice was promoted in both mice groups fed ad libitum and forcedly with live vibrios but not with killed microorganisms. Total IgA in the intestinal contents of mice fed with live vibrios both ad libitum and forcedly were higher than those of mice fed with killed antigens. In addition, when the extracts of intestinal contents were absorbed by live antigens, IgA contents in mice fed with live vibrios were reduced more markedly than those in mice immunized orally by the feeding with killed antigens. These findings suggested that the elimination of vibrios from the organ was closely related to local IgA antibody response to heat-labile substance of live Vibrio cholerae.

Enhancement of host defence by Y-19995 (2,4'-bis(1-methyl-2-dimethyl-aminoethoxyl)-3-benzoylpyridine dimaleate), a novel synthetic compound. I. Accelerated restoration from the leukocytopenia and augmented protection against microbial infections in immunocompromised mice

Effects of a novel synthetic compound, Y-19995, on the host defence in immunocompromised mice were investigated in terms of the restoration of leukocytopenia and the protection against several microbial infections. Oral or intravenous administration of Y-19995 into mice after X-irradiation, treatment with cyclophosphamide or mitomycin C prevented the leukocytopenia to some extent and promoted the restoration in cell numbers of both the peripheral blood leukocytes and bone marrow. Intravenous administration of Y-19995 increased significantly the survival rates of X-ray irradiated mice against acute systemic infections with Escherichia coli, Pseudomonas aeruginosa and Candida albicans, and intramuscular infection with Escherichia coli. The clearance of Escherichia coli from the blood of X-ray irradiated mice was also promoted by the treatment with Y-19995. The augmented protection against microbial infections in immunocompromised hosts by Y-19995 may be attributed mainly to the prevention of leukocytopenia or the enhanced restoration from leukocytopenia.

Contradictory responses in induction of delayed type hypersensitivity in orally immunized mice

Induction of delayed type hypersensitivity (DTH) in mice fed with sheep red blood cells (SRBC) and live Vibrio cholerae (V. cholerae) both forcedly and ad lib was comparatively investigated. Although suppression of DTH to SRBC or V. cholerae was induced in mice fed forcedly for 1 or 2 weeks, mice fed ad lib could produce the positive footpad reactions to antigens. Furthermore, the suppression of DTH in forcedly fed mice showed an antigenic specificity. These observations indicated that the induction of unresponsiveness to DTH in orally immunized mice was markedly influenced by the oral administration.

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.

Cholera toxin-induced tolerance to allografts in mice

When C3H/HeN (C3H) mice were primed with viable C57BL/6 (B6) spleen cells and treated with cholera toxin (CT) on the same day, a profound tolerance to tumour allografts of B6 origin was induced. The tolerant state was sustained for as long as 6 weeks or more. Skin allografts of B6 were rejected by such tolerant C3H mice, although the survival times were prolonged very slightly. Generation of cytotoxic T lymphocytes was reduced markedly in the tolerant mice, whereas delayed footpad reaction to B6 cells was maintained at the normal immune level or higher. There is a possibility that a T-cell subset responsible for delayed footpad reaction is resistant to CT-induced tolerance and participates in the rejection of skin allografts in tolerant mice.

Differing resistance to polymorphonuclear cells of halophilic- and hypotonic-types of Vibrio vulnificus

Bacterial growth and lethality of 4 strains of Vibrio vulnificus infection of mice were enhanced by gamma-irradiation but not by treatment with carrageenan. Therefore, protection against V. vulnificus, at least in the early phases, probably depends mainly on polymorphonuclear cells (PMN), since carrageenan depletes macrophages but not PMN. PMN dependent protection against infection differs for 2 types of V. vulnificus strains. Halophilic- and hypotonic-type were distinguished from the corresponding parent strain. The hypotonic-type of the strains had capsular materials, as clarified by electron microscopic observation of the organisms stained with ruthenium red. On the other hand, halophilic-types either had no observable capsular materials, or incomplete materials, in contrast to the corresponding hypotonic-type. The corresponding halophilic- and hypotonic-types of the strains were compared for virulence in mice. The strains with capsular materials acquired resistance to phagocytic activity and were highly lethal. Capsular materials of V. vulnificus are no doubt important for the expression of virulence.

Protective mechanisms against pulmonary infection with influenza virus. I. Relative contribution of polymorphonuclear leukocytes and of alveolar macrophages to protection during the early phase of intranasal infection

The relative contribution of polymorphonuclear leukocytes and macrophages in the early protection against intranasal infection of mice with influenza virus was investigated. Virus multiplication in the lung in the early phase of infection with less than 1.5 X 10(3) plaque-forming units was enhanced by X-ray irradiation. The intranasal administration of carrageenan did not influence the titre of virus. However, when mice were infected with 1.5 X 10(4) plaque-forming units, the virus titre was elevated by intranasal administration of carrageenan as well as by X-ray irradiation, but not by intraperitoneal administration of carrageenan. The intranasal administration of carrageenan not only inhibited the phagocytic activity of alveolar macrophages but also enhanced susceptibility to the virus. On the other hand, polymorphonuclear leukocytes were capable of phagocytosing the virus in vitro and were non-permissive for virus infection. Neutralizing antibody and interferon were not detectable in the early stage of the infection. These results suggested that polymorphonuclear leukocytes (X-ray-sensitive, carrageenan-resistant) were the cells primarily responsible for early protection in influenza virus infection and that after infection with a high dose of the virus alveolar macrophages (X-ray-resistant, carrageenan-sensitive) also played a protective role in the early phase.

Mechanism of protection during the early phase of a generalized viral infection. II. Contribution of polymorphonuclear leukocytes to protection against intravenous infection with influenza virus

The contribution of phagocytes to the early protection of mice inoculated intravenously with influenza virus was investigated in phagocyte-depleted mice. Following the inoculation of a sublethal dose of influenza virus, virus titres in the liver and lung of both untreated and carrageenan-treated mice were reduced rapidly by day 1 and decreased slowly to reach an undetectable level by day 7. The titres in gamma-irradiated mice decreased transiently by day 1 and increased progressively thereafter to kill all of the hosts by day 8. The clearance of virus from blood at the early stage of infection was retarded by gamma-irradiation but not by carrageenan treatment. In addition, increase in virus titres in the liver and lung in the early stage of the infection was prevented by adoptive transfer with syngeneic polymorphonuclear leukocytes into gamma-irradiated mice. No significant rise of neutralizing antibody was detectable by day 3 after the inoculation, in any of the three groups of mice. These observations imply that gamma-sensitive and carrageenan-resistant polymorphonuclear leukocytes play a protective role at the early stage in the infection, whereas fixed macrophages or natural killer cells, both of which are carrageenan-sensitive and gamma-resistant, scarcely participate in the early phase.

Antitumor activity of protein-bound polysaccharide from Cordyceps ophioglossoides in mice

The effects of protein-bound polysaccharide (SN-C) extracted from Cordyceps ophioglossoides on the growth of transplanted allogeneic and syngeneic murine tumors were studied. SN-C given by intraperitoneal administration suppressed the growth of sarcoma-180 transplanted subcutaneously in mice. Intraperitoneal administration of SN-C also caused a significant prolongation of the life span of ICR mice inoculated intraperitoneally with Ehrlich carcinoma, and C3H/He mice inoculated intraperitoneally with a syngeneic tumor (X-5563). SN-C showed a significant cytocidal effect on cultured tumor cells. SN-C did not affect delayed-type hypersensitivity (DTH) in normal mice, but restored the depressed capacity to raise DTH in tumor-bearing mice. These results suggested that SN-C may exert both direct and host-mediated antitumor effects.

Induction of interleukin 2 receptor gene expression by p40x encoded by human T-cell leukemia virus type 1

Human T-cell leukemia virus type 1 (HTLV-1) is an etiologic agent of adult T-cell leukemia (ATL). A viral product, p40x, encoded by the pX sequence of HTLV-1 is a trans-acting transcriptional activator of the long terminal repeat (LTR) and has been suspected of involvement in leukemogenesis, activating the cellular genes. The cellular interleukin-2 (IL-2) and its receptor (IL-2R), the latter of which is expressed on ATL leukemic cells, were shown to be transiently induced by transfection of plasmid pMTPX expressing pX in two T-cell lines, Jurkat and HSB-2, but not in other human T- or B-cell lines. The cell type specificity of IL-2R induction by pX expression was the same as that by phytohaemagglutinin/phorbol ester activation, indicating the requirement for some specific cellular factors or a certain state of cellular differentiation. Induction of IL-2 and IL-2R at mRNA level was also demonstrated in transfected cells. Transfections with mutants of pMTPX in which the open reading frames for p40x, p27x-III and p21x-III were inactivated indicated that p40x alone was sufficient for induction of the IL-2R in inducible cells. This induction of the IL-2R by p40x of HTLV-1 may contribute to preferential proliferation of HTLV-1 infected cells at an early stage of ATL development and eventually increase the number of putative target cells for malignant transformation.

Immune protective mechanisms during pregnancy. I. Cell-mediated immunity against Listeria monocytogenes in pregnant mice

Characteristics of protective mechanisms during pregnancy were investigated using neonatally thymectomized (NTx) and/or pregnant mice infected with sublethal doses of Listeria monocytogenes, of which the explosive growth at an early phase of 2 or 3 days after infection is prevented by non-immune macrophages, and complete elimination at a late phase from 4 to 10 days after infection is attributed to the augmented functions of macrophages in co-operation with lymphokine-producing sensitized T lymphocytes. Although in virgin control mice there was a gradual decline of bacteria from the day after infection, viable bacteria in pregnant mice showed an increase in number until Day 3. In such pregnant mice, carbon clearance was suppressed. Thus, the enhanced bacterial growth in pregnant mice within 3 days may be attributable to the suppressed functions of non-immune macrophages. Complete elimination of Listeria from Day 4 was observed in pregnant sham-operated mice as well as in non-pregnant and pregnant NTx mice. Twenty-four hour reaction of delayed-type in normal mice induced by sheep red blood cells (SRBC) in incomplete Freund's adjuvant (IFA) was not affected by pregnancy, while 48 hr reaction in mice immunized with SRBC in complete Freund's adjuvant (CFA) was suppressed by pregnancy. We have reported previously that macrophage migration inhibitory factor (MIF) was produced in the latter but not in the former, and that the tuberculin type of delayed hypersensitivity accompanied by MIF production scarcely participated in acquired resistance to Listeria. Effective elimination of Listeria in pregnant and/or NTx mice at a late phase may be attributable to the activity of cellular immunity comparable to 24 hr reaction. These results suggest that T cells showing a low degree of thymus dependency in the ontogenic development may be the major component required for acquired protective immunity against Listeria and may account for the protection in pregnant mice.

Response of bacterial antigen in palmoplantar pustulosis

Motilities of leukocytes in response to bacterial antigens or sera were examined in tissues from patients with palmoplantar pustulosis (PPP). Accelerated migration towards bacterial antigens was detected in the case of Staphylococcus epidermidis in 9 of 19 patients, to Propionibacterium acnes in 5 of 19, to Proteus mirabilis and Staphylococcus aureus in 3 of 19, while no acceleration was found in neutrophils from the controls. A significantly accelerated migration of normal lymphocytes in response to both patients' and control sera was nil. Inhibition of migration of guinea pig peritoneal exudate cells mixed with lymphocytes from PPP patients was detected in 12 out of 14 patients with the addition of S. epidermidis antigen and 8 of 14 with the addition of P. acnes antigen, while no such inhibition was detected in all 7 controls. The accelerated migration of neutrophils and inhibition of macrophages may participate in the development of PPP.

[Changes in nonspecific suppressor factors in the serum of gastric cancer patients after surgery and immunochemotherapy]

After curative surgery for gastric cancers judged macroscopically to be at stage 2 or 3, patients were divided into 4 groups by randomization. As the basic treatment, patients were given one-shot Mitomycin and Tegafur as maintenance therapy for 8 months (group A). PSK (group B), OK-432 (group C) or both PSK and OK-432 (group D) were added to the treatment of group A for 8 months. Sera were obtained from these groups of patients at 4 weeks and 3, 6, 9 and 12 months after surgery. In all of these groups, values of IAP increased slightly at 4 weeks but decreased at 3 months and were maintained at such a level by 12 months. On the other hand, suppressive effects of such sera on the blastogenesis of murine spleen cells in response to PHA varied among these group. In groups A and C, the suppressive effect of sera increased after surgery and was detected continuously by 12 months. In groups B and D, in contrast, the suppressive effect disappeared from 3 to 12 months. The rise and fall of such a suppressive effect of sera may reflect the mode of action of PSK.

Depression of protective mechanism during the early phase of a viral infection in tumor-bearing mice and prevention by PSK

Effector mechanisms responsible for resistance against ectromelia virus including antiviral activity of non-immune macrophages, antiviral antibody, delayed footpad reaction to viral antigen, and interferon induction after viral infection were depressed in BALB/c mice bearing syngeneic Meth A tumor. The degree of viral growth correlated well with the depression of delayed footpad reaction, antibody production, and interferon induction. Therefore, modification of macrophage functions by a tumor-bearing state and treatment with PSK may contribute to this modification of antiviral resistance, at an early phase of infection. Cytotoxic activity may not be the principal effector, since the cytotoxicity was induced in normal and tumor-bearing mice to almost the same extent yet an extensive viral growth occurred only in the latter.

Immunological studies on Crohn's disease. V. Enumeration of circulating lymphocytes subsets using monoclonal antibodies

We found normal levels of suppressor cell activity and reduced natural killer (NK) and antibody dependent cell-mediated cytotoxicity (ADCC) activities in patients with Crohn's disease (CD). To further characterize these activities, studies were carried out using monoclonal antibodies. There were no changes in the proportion of OKT4+ (helper/inducer T cells), OKT8+ or Leu 2+ (suppressor/cytotoxic T cells) and Leu 7+ (large granular lymphocytes: LGL, NK + K cells), thereby suggesting that suppressor cell activity in CD is likely to be normal both in function and in number, and that depressed NK and ADCC activities are not due to a reduction in the number of NK or K cells but rather to functional defects. Using a double staining method, we noted a low percentage of both Leu 2 and Leu 7 positive cells in CD.

Mechanisms of in vivo generation of cytotoxic activity against syngeneic tumours. I. Local differentiation of mature cytotoxic T lymphocytes in the rejection of tumours

Mature cytotoxic T lymphocytes (CTL) were detected in the peritoneal cavity of syngeneic mice immunized intraperitoneally (i.p.) with mitomycin C (MC)-treated EL-4 or X5563 cells, but were not found in their spleens or lymph nodes. Mature CTL appeared among PE cells after transfer of spleen cells from those immune mice, along with MC-treated tumour cells, to the peritoneal cavity of syngeneic mice. These results lead us to the hypothesis that immature CTL primed in the spleen and lymph nodes may migrate to the site of tumour inoculation and differentiate into mature CTL after antigenic or non-specific stimulation at that site. Inability of primed CTL to differentiate to mature CTL in the spleen might be explained by the effect of splenic suppressor cells, since mature CTL became detectable in the spleen of immune mice by treatment with cyclophosphamide.

[Augmentation of resistance against metastatic tumor cells after local administration of PSK]

Local administration of PSK augmented the generation of cytotoxic lymphocytes and the induction of resistance against metastatic tumor. Augmented generation of cytotoxic lymphocytes may be ascribed to local effects of PSK in the lymph nodes, since this is mediated by Lyt-1+2+ cells. Local administration of PSK increased the threshold number of metastatic tumors eliminated by hosts. This finding seems to be important in relation to augmentation of resistance against metastasis or local implantation with a limited number of tumor cells.

Effect of PSK on interferon production in tumor-bearing mice

The effect of PSK on the depressed interferon (IF) production in tumor-bearing mice was studied. In tumor-bearing mice, in vitro IF production by spleen cells treated with polyinosinic-polycytidylic acid (poly I:C) was remarkably inhibited. However, these inhibitions were prevented by the intraperitoneal (ip) administration of PSK. Mice were inoculated intravenously (iv) with poly I:C-treated spleen cells, administered with PSK ip at 3 days after the tumor inoculation. When PSK was not given, poly I:C-treated spleen cells did not show an inhibitory effect on tumor growth. In mice given PSK ip, poly I:C-treated spleen cells exerted slightly inhibiting effects on tumor growth. These results suggest that PSK prevented such a modulation in tumor-bearing mice.

Entrance of cholera enterotoxin subunits into thymus cells

Analysis of the staining of cholera enterotoxin on the surface of cells with specific antibodies against each subunit of cholera enterotoxin, using a fluorescence-activated cell sorter and electron microscopy, showed that not only subunit A but also subunit B penetrates the cell membrane. The detection of subunits inside the cell was facilitated by the use of saponin, an agent that increases membrane permeability.

[Depression of protective mechanisms against ectromelia virus infection in tumor-bearing mice and its prevention by PSK]

Effector mechanisms responsible for protection against ectromelia virus (EMV) including antiviral activity of non-immune macrophages, cytotoxic T cells, antiviral antibody, delayed footpad reaction to viral antigen and interferon induction after viral infection were depressed in BALB/c mice bearing syngeneic Meth A tumors. The degree of viral growth correlated well with the depression of delayed footpad reaction, antibody production and interferon induction. But a control level of these elements could be obtained by pretreatment of tumor-bearing mice, with PSK Cytotoxic activity may not be the principal effector, since cytotoxicity was induced in both normal and tumor-bearing mice to almost the same extent but an explosive viral growth was observed only in the latter. These results suggest that PSK was responsible for restoring the depressed antiviral protective immunity to normal levels in tumor-bearing animals.

[Effect of PSK on the recovery of macrophage function and T cell-mediated immunity in tumor-bearing mice]

The effect of PSK on the depressed bactericidal activity of macrophages and delayed-type hypersensitivity (DTH) to Listeria monocytogenes in BALB/c mice bearing transplantable Meth A fibrosarcoma was studied. In tumor-bearing mice pretreated with PSK, L. monocytogenes was cleared rapidly from the circulating blood and bacterial growth in the liver was inhibited effectively in the early phase of infection. This resistance to the infection could be transferred with peritoneal exudate cells (PEC) but not with non-adherent PE cells of PSK-treated mice. In the early phase of infection, tumor-bearing mice developed a lower level of DTH to L. monocytogenes than did nongrafted control mice. However, the control levels of DTH could be obtained by pretreatment of tumor-bearing mice with PSK. These results suggest that the restoration of resistance to L. monocytogenes in tumor-bearing mice by PSK may be ascribed to both prevention of depression or activation of macrophage function and prevention of depression of T cell-mediated immunity.

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.

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.

Relationship between bactericidal and phagocytic activities of peritoneal macrophages induced by irritants

Cellular accumulation to the peritoneal cavity and modification of various functions of peritoneal macrophages were observed in mice injected intraperitoneally (ip) with thioglycollate medium (TG), liquid paraffin, proteose peptone and Corynebacterium parvum. The cellular composition of peritoneal exudates at 4 days after injection of irritants was almost the same in all the groups and the proportion of macrophages was increased approximately 4 times more than nontreated controls. The ability to kill Listeria monocytogenes and to generate chemiluminescence (CL) were augmented strongly in C. parvum-induced macrophages, while depressed in TG-induced macrophages. The activities of liquid paraffin- or proteose peptone-induced macrophages were almost the same as those in nontreated controls. However, the ability to phagocytose native sheep erythrocytes was greatly augmented both in C. parvum- and TG-induced macrophages. There is thus a discrepancy between bactericidal activity and phagocytic activity among macrophages induced with various irritants.

Depression of macrophage functions and T-cell-mediated immunity to listeria infection in tumor-bearing mice and its prevention by PSK

The effect of PSK on the depressed bactericidal activity of macrophages and delayed-type hypersensitivity (DTH) to Listeria monocytogenes in BALB/c mice bearing transplantable Meth A fibrosarcoma was studied. In tumor-bearing mice pretreated with PSK, L. monocytogenes was cleared rapidly from the circulating blood and bacterial growth in the liver was inhibited effectively in the early phase of infection. This resistance to the infection could be transferred with adherent peritoneal exudate cells (PEC) but not with nonadherent or adherent spleen cells of PSK-treated mice. In the early phase of infection, tumor-bearing mice developed a lower level of DTH to L. monocytogenes than nongrafted control mice. However, the control levels of DTH could be obtained by pretreatment with PSK in tumor-bearing mice. These results suggest that the restoration of DTH to L. monocytogenes by pretreatment with PSK may be attributable to the restoration of the depressed immunological responsiveness to the normal levels in tumor-bearing mice.

Cholera toxin-binding T cells in the human peripheral blood at different ages

The capacity of human T cells to bind cholera toxin was shown to decrease with age. In aged humans, the number of cells capable of binding high concentrations of cholera toxin was lower than that in young humans. The method presented in this paper may be useful as one of the indicators of aging of the immune system.

Separation of osteoblast-like cells from bone marrow by fluorescence-activated cell sorting

The purification of the osteoblast-like cells (2-3%) among the bone marrow cells (BMC) of C57BL/6 mice using a specific anti-osteoblast serum and a fluorescence-activated cell sorter is described. The antiserum was raised against osteoblast cells isolated from calvaria from neonatal mice. The majority of the cells of the osteoblast-enriched fraction from bone marrow showed a parathormone-induced increase in cyclic adenine monophosphate but no response to calcitonin. This is similar to the response of osteoblast cells obtained from the calvaria. Electron microscopic studies of the extracellular matrix of cultured osteoblast-like cells purified from bone marrow showed the deposition of apatite crystals within and in close apposition to the vesicles. These findings suggest that the isolated cell population was enriched in osteoblasts. Such a cell system from bone marrow might provide an experimental system for investigating the mechanism of bone formation.

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.

Mechanism of protection during the early phase of a generalized viral infection. I. Contribution of phagocytes to protection against ectromelia virus

Effects of carrageenan and gamma-irradiation on virus titre in the liver were observed after intravenous inoculation of 8 X 10(3) p.f.u. of ectromelia virus which was not lethal for untreated mice. Trapping of virus by the liver within 30 min and an initial transient reduction in titre by day 1 were not affected by gamma-irradiation but were inhibited by pretreatment with carrageenan. An increase from day 1 to day 3 was not affected by gamma-irradiation but was augmented by pretreatment with carrageenan. Therefore, protection within 3 days may depend principally upon carrageenan-sensitive and irradiation-resistant cells, namely, fixed macrophages. Elimination of virus from day 4 to day 7 depended upon cell-mediated immunity. When carrageenan was given 3 days after virus inoculation, the titre of virus increased progressively from day 4 ultimately to kill the hosts. The cytotoxic activity of spleen cells against infected target cells was raised in carrageenan-treated mice as well as in untreated mice. Immune elimination of virus may be mediated by a mechanism requiring the cooperation of sensitized T lymphocytes and blood monocytes.

Augmented delayed footpad reaction in thymus cell-depleted mice induced by cholera toxoid

One hundred microgram of cholera toxoid was injected intravenously into DDD and AKR mice and its effects on lymphoid tissues and immune responses against sheep erythrocytes (SRBC) were examined at various times after the injection. (1) A remarkable reduction of thymus cells was revealed from day 1 to 7 and from day 1 to 4 in DDD and AKR mice, respectively. (2) Cholera toxoid exhibited only slight effects on the numbers of spleen cells and peripheral blood leukocytes in both strains. (3) Delayed footpad reactions to SRBC were augmented by a pretreatment with cholera toxoid 4 or 7 days before immunization in both strains. The delayed reactions were not suppressed in the presence of a prominent antibody production and were accompanied by positive macrophage migration inhibition. (4) Antibody production against SRBC, especially of IgG class, was facilitated, when cholera toxoid was given 7 days before the immunization through the footpad in DDD mice. On the other hand, antibody production was suppressed irrespective of immunizing routes and mouse strains, when cholera toxoid was given 1 day before immunization.

Involution of the thymus in tumor-bearing mice and its restoration by PSK

In Balb/C mice, the size and weight of the thymus and the number of thymus cells were reduced 1 week after the subcutaneous inoculation of Meth A fibrosarcoma. These changes were prevented by the intraperitoneal administration of PSK. In normal mice, the majority of thymus cells are large and the minority are small as demonstrated by analysis with a fluorescence activated cell sorter. In tumor-bearing mice, the number of large cells are decreased and the number of small cells are relatively increased. PSK prevented such a modulation in tumor-bearing mice.

Effects of cholera toxin on the lymphoid system. III. In vivo generation of cytotoxic lymphocytes

Cytotoxic T lymphocytes (CTL) were generated in the spleen by subcutaneous inoculation of EL-4 leukaemia cells (H-2b) into C3H/He mice (H-2k). (1) Cytotoxicity of spleen cells was profoundly suppressed by an intravenous injection of 1 microgram cholera toxin on the day of tumor inoculation. Tumors continued to grow progressively. (2) Differentiation of memory cells to mature CTL was suppressed by cholera toxin injection on the day of booster inoculation of EL-4 cells. The tumors grew progressively in immune mice given cholera toxin on the day of the booster. (3) In vitro treatment of CTL with cholera toxin suppressed the expression of their cytotoxic activity to a considerable extent. However, tumors regressed very rapidly after rechallenge to immune mice carrying CTL, even when cholera toxin was injected on the day of rechallenge. Cholera toxin suppressed not only the functional expression of CTL but also the induction phase of CTL generation.

Effects of PSK on specific tumor immunity to syngeneic tumor cells

Substantial degrees of resistance against rechallenge with viable tumor cells and cytotoxic activity of peritoneal exudate cells (PE cells) as detected by in vitro 51Cr-release test or in vivo Winn's test were raised by immunization with Mitomycin C-treated EL-4 tumor cells in syngeneic C57BL/6J mice. Cytotoxicity of PE cells was found to reside in glass-nonadherent and anti-Thy 1.2-sensitive population, while such activity was not detected within the spleen and mesenteric lymph nodes. Intraperitoneal or oral administration of PSK augmented such resistance or cytotoxicity.

[Effect of solcoseryl and combined therapy of solcoseryl and FT-207 for mice bearing meth-A tumor]

The effects of a combined chemotherapy of solcoseryl and FT-207 on tumor growth, delayed hypersensitivity and cell population of the spleen were studied using inbred BALB/c mice. Meth-A tumor cells (2 X 10(6] were inoculated into the back of 5 to 6 week old BALB/c male mouse. Animals were divided into three groups: Solcoseryl group, in which 0.04 mg of solcoseryl was injected intravenously three times before inoculation and four times after inoculation; Combined group, in which 1.2 mg of FT-207 and 0.04 mg of solcoseryl were injected intravenously four times after inoculation; FT-207 group, in which 1.2 mg of FT-207 was injected four times after inoculation, with out solcoseryl administration. Following results were obtained: Solcoseryl group showed enhanced immunity and tumor suppression; Decreased immunity due to FT-207 was recovered by administration of solcoseryl but no tumor suppression was observed and, Decreased T-cell population of spleen due to FT-207 was recovered by administration of solcoseryl. These facts suggested that solcoseryl was useful because of making recovery possible from decreased immunity due to chemotherapy.

Production by cultured spleen cells of inflammatory substances and other lymphokines that mediate delayed-type hypersensitivity in mice

In vitro cultivation of normal mouse spleen cells with human serum albumin generated effector cells that mediate the delayed-type hypersensitivity (DTH) reaction. The cultured cells, when incubated in a serum-free medium for a further 24 hr, released substances (FPRF) which caused a footpad inflammatory reaction at a maximum of 6 hr after injection into normal syngeneic or allogeneic strains of mice, as well as macrophage migration inhibition factor (MIF) and macrophage activating factor (MAF). The DTH-effector cells in the culture were fractionated in the low density layers by discontinuous bovine serum albumin density gradient centrifugation. The effector cells in the low density layers were further enriched in the Lyt 1 subpopulation of T cells when fractionated on a fluorescence activated cell sorter. Cells capable of producing the inflammatory substances (FPRF), MIF and MAF were also enriched in the same fraction containing DTH-effector cells. These results suggest that low density, Lyt 1-positive T cells mediating the DTH reaction produce FPRF as well as MIF and MAF.