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PubMed1998

[Effects of composite blood-activating decoction on bone marrow microenvironment in mice of immune-induced aplastic anemia].

OBJECTIVE: To explore the mechanism of elevating efficacy for aplastic anemia (AA) by using blood-activating and stasis-eliminating drugs. METHODS: Immune-induced aplastic anemia model was established. Each mouse was gastrogavaged by 0.2 ml 100% composite blood-activating decoction (CBAD) twice a day. On the 10th day, the bone marrow histology, CFU-F, adhesive function of the cultured stromal cell layer, bone marrow PO2 were observed. RESULTS: In CBAD group, the WBC count, bone marrow karyocytes, bone marrow hematopoietic tissue volume, CFU-F count were significantly higher than those in AA group (P < 0.01). Moreover, the adhesive function of stromal cells and bone marrow PO2 recovered to normal level. CONCLUSION: The commonly used composite blood-activating decoction could promote the recovery and oxygen-supply of bone marrow microenvironment in AA mice, and improved the bone marrow hematopoiesis.

Anemia, Aplastic↗
PubMedDate not supplied

Sustained Release of Granulocyte-Macrophage Colony-Stimulating Factor From a Modular Peptide-Based Cancer Vaccine Alters Vaccine Microenvironment and Enhances the Antigen-Specific T-Cell Response.

SUMMARY: The recent identification and molecular characterization of tumor antigens provides the opportunity to explore the rational development of peptide-based cancer vaccines. However, the response to these vaccines remains variable, and peptide-based cancer vaccines may even produce tolerance induction and enhanced tumor growth. The authors have developed a unique method for the isolation of a polysaccharide polymer of chemically pure poly- N -acetyl glucosamine (p-GlcNAc). This highly purified polysaccharide can be formulated into a stable gel matrix (designated F2 gel matrix) with unique properties of a sustained-release delivery system that has previously been shown to be an effective immune adjuvant. F2 gel matrix is capable of providing sustained release of antigenic peptide and cytokine in vitro. The purposes of this study were to characterize the ability of F2 gel matrix to provide sustained local release of cytokines in vivo and to test the hypothesis that such sustained release can enhance the microenvironment for antigen presentation, leading to a more effective antitumor response. Subcutaneous administration of F2 gel/cytokine matrix resulted in sustained release of cytokine at the vaccine site for up to 120 hours. Sustained release of granulocyte-macrophage colony-stimulating factor (GM-CSF) was associated with an increased inflammatory infiltrate at the vaccine site and enhanced dendritic cell activation. Further, accination with F2 gel/SIINFEKL/GM-CSF matrix resulted in enhanced antigen-specific immunity. Addition of GM-CSF to the F2 gel matrix resulted in an increase in the percentage of antigen-specific T cells in the draining lymph nodes, enhanced cytotoxicity, a sustained presence of antigen-specific T cells in the peripheral blood, and protection from E.G7 tumor challenge. These results support the potential of an F2 gel matrix modular vaccine delivery system that can provide sustained local release of cytokine in vivo, and confirm the powerful effects of GM-CSF as an immune adjuvant.

Journal Article↗
PubMedDate not supplied

Sustained release of granulocyte-macrophage colony-stimulating factor from a modular peptide-based cancer vaccine alters vaccine microenvironment and enhances the antigen-specific T-cell response.

The recent identification and molecular characterization of tumor antigens provides the opportunity to explore the rational development of peptide-based cancer vaccines. However, the response to these vaccines remains variable, and peptide-based cancer vaccines may even produce tolerance induction and enhanced tumor growth. The authors have developed a unique method for the isolation of a polysaccharide polymer of chemically pure poly- N -acetyl glucosamine (p-GlcNAc). This highly purified polysaccharide can be formulated into a stable gel matrix (designated F2 gel matrix) with unique properties of a sustained-release delivery system that has previously been shown to be an effective immune adjuvant. F2 gel matrix is capable of providing sustained release of antigenic peptide and cytokine in vitro. The purposes of this study were to characterize the ability of F2 gel matrix to provide sustained local release of cytokines in vivo and to test the hypothesis that such sustained release can enhance the microenvironment for antigen presentation, leading to a more effective antitumor response. Subcutaneous administration of F2 gel/cytokine matrix resulted in sustained release of cytokine at the vaccine site for up to 120 hours. Sustained release of granulocyte-macrophage colony-stimulating factor (GM-CSF) was associated with an increased inflammatory infiltrate at the vaccine site and enhanced dendritic cell activation. Further, accination with F2 gel/SIINFEKL/GM-CSF matrix resulted in enhanced antigen-specific immunity. Addition of GM-CSF to the F2 gel matrix resulted in an increase in the percentage of antigen-specific T cells in the draining lymph nodes, enhanced cytotoxicity, a sustained presence of antigen-specific T cells in the peripheral blood, and protection from E.G7 tumor challenge. These results support the potential of an F2 gel matrix modular vaccine delivery system that can provide sustained local release of cytokine in vivo, and confirm the powerful effects of GM-CSF as an immune adjuvant.

Acetylglucosamine↗
PubMed2001

[Influence of chemotherapy on hematopoietic microenvironment and effect of autologous bone marrow stromal cell infusion on the recovery of hematopoiesis after chemotherapy].

OBJECTIVE: To observe the influence of chemotherapy on hematopoietic progenitor cells (HPC) and hematopoietic microenvironment (HME). To observe whether intravenous infusion of autologous bone marrow stromal cells (ABMSC) expanded in vitro can improve the hematopoietic function. METHODS: Cultures of CFU-GM, BFU-E, CFU-E and stromal progenitor cells (CFU-F) from normal control and chemotherapeutic patients were performed. The stromal function was analyzed by the assessment of the area of flask surface covered by stromal cells (ASSC) and the time when stromal cells reach confluence (TC). The recovery of hematopoietic function in short term chemotherapy group and long term chemotherapy, with or without ABMSC infusion (1.1 - 8.7) x 10(8) post chemotherapy groups was observed. RESULTS: The yields of CFU-GM, BFU-E, CFU-E and CFU-F in long term chemotherapy group were significantly lower than that in normal group or in short term chemotherapy group. There was no significant difference among three groups in the ASSC and TC. In long term chemotherapy group, the yields of CFU-GM, CFU-E, BFU-E and CFU-F after chemotherapy with BMSC infusion were significantly higher than that without BMSC infusion. In long term chemotherapy group, the lowest value of white blood cell (WBC) and platelet after chemotherapy with BMSC infusion was significantly higher than that without BMSC infusion. The times for WBC and platelets recovered to normal were significantly shorter in BMSC group than in without BMSC. No adverse reaction was observed with ABMSC infusion. CONCLUSION: Long term chemotherapy results in severe impairment in HPC and mesenchymal progenitor cell (MPC), but has no obvious influence on the in vitro BMSC confluent layer formation. Intravenous infusion of expanded ABMSC can accelerate the recovery of hematopoiesis after chemotherapy.

Adolescent↗
PubMed2002

[Desorption of kaolin adsorbed copper in the fish gill microenvironment].

In order to investigate the bioavailability of kaolin adsorbed copper on gills of carpio, and to explain its possible mechanism in terms of speciation, exposure experiments with constant concentration of water soluble copper and increased concentration of kaolin adsorbed copper was carried on, and the speciation analyses was developed using MINTEQA2. The results of the exposure experiment indicated that expose to kaolin adsorbed copper would increase the metal accumulation in the fish gills. The shift of the copper speciation was demonstrated via chemical equilibrium calculation. To be specific, the kaolin adsorbed copper would be partially desorbed in the fish gill microenvironment in the alkaline water environment.

Adsorption↗
PubMedDate not supplied

Restoration of the thymic cellular microenvironment following autologous bone marrow transplantation.

Mammalian thymic histogenesis can be morphologically divided into three consecutive stages: 1) epithelial; 2) lymphopoietic or lympho-epithelial; and 3) differentiated cellular microenvironmental, with formation of Hassall's bodies (HBs). The marked reduction of the thymic cellular microenvironment (TCM) is a well-controlled physiological process and is presumably under both local and global regulation by the cells of the RE meshwork and by the neuroendocrine axis, respectively. In humans, the age-related decline of facteur thymique sérique (FTS) levels in blood begins after 20 years of age and FTS completely disappears between the 5th and 6th decade of life. In contrast, serum levels of thymosin-alpha 1 and thymopoietin seem to decline earlier, starting as early as 10 years of age. The influences of other hormones on the thymic involution have also been characterized: testosterone, estrogen and hydrocortisone treatment results in marked involution, cortisone and progesterone administration causes slight to moderate, while use of desoxycorticosterone has no effect. Since the thymus is the primary T-lymphopoietic organ during mammalian ontogenesis, its age-related involution with the typical immunomorphological alterations can be held responsible only for a decline in antigen-specific T-lymphocyte immune functions. Thymic involution and diminished T-lymphocyte proliferation can be partially restored by thymic tissue transplantation or administration of thymic hormones. The stimulus for thymic cell proliferation and differentiation is genetically determined within the organ implant. The only partial reconstitution of CD4+ T-helper-lymphocyte subset after anti-neoplastic chemotherapy and autologous BTM represents a significant, therapy-complicating, clinical problem. After high-dose chemotherapy, the restoration of thymus-dependent CD4+ T-lymphocyte genesis was reported only in children. Our radiation, stem cell transplantation, and hormone treatment experiments in animals resulted in age- and time-dependent regeneration of the cytoarchitecture of the TCM, as well as intrathymic lymphopoiesis.

Biopsy, Needle↗
PubMed2002

The vascular endothelial growth factor receptor tyrosine kinase inhibitor PTK787/ZK222584 inhibits growth and migration of multiple myeloma cells in the bone marrow microenvironment.

Our prior studies show that multiple myeloma (MM) cell lines and patient cells express high-affinity vascular endothelial growth factor (VEGF) receptor (VEGFR) Flt-1 but not Flk-1/KDR. Moreover, these studies have shown that VEGF induces proliferation and migration of MM cells, and we have begun to delineate the signaling cascades mediating those sequelae. In this study, we examined the activity of PTK787/ZK 222584 (PTK787), a molecule designed to bind specifically to the tyrosine kinase domain of VEGFR and inhibit angiogenesis. We show that PTK787 acts both directly on MM cells and in the bone marrow microenvironment. Specifically, PTK787 (1-5 micro M) inhibits proliferation of MM cells by 50%, as assayed by [(3)H]thymidine uptake. This effect of PTK787 is dose dependent in both MM cell lines and patient cells that are both sensitive and resistant to conventional therapy. PTK787 enhances the inhibitory effect of dexamethasone on growth of MM cells and can overcome the protective effect of interleukin 6 (IL-6) against dexamethasone-induced apoptosis. PTK787 (1 micro M) also blocks VEGF-induced migration of MM cells across an extracellular matrix. Importantly, PTK787 also inhibits the increased MM cell proliferation and increased IL-6 and VEGF secretion in cultures of MM cells adherent to bone marrow stem cells. These findings therefore demonstrate that PTK787 both acts directly on MM cells and inhibits paracrine IL-6-mediated MM cell growth in the bone marrow milieu. The demonstrated anti-MM activity of PTK787, coupled with its antiangiogenic effects, provides the framework for clinical trials of this agent to overcome drug resistance and improve outcome in MM.

Bone Marrow↗
PubMed1975

Studies of the hemopoietic microenvironment. IV. In vivo microscopic and histochemical study of allografts of bone marrow in the hamster cheek pouch chamber.

Within a transparent chamber enclosing subcutaneous tissue of the hamster cheek pouch, allogeneic femoral marrow was grafted. This permitted in vivo microscopic study of the grafts for 14 days. Five to seven days after grafting, blood flow was established within sinusoids arranged in interconnecting polygonal networks, a pattern characteristic of marrow. All vessels appeared to have a complete and continuous endothelial lining. The graft contained foci of erythropoiesis, granulopoiesis, and megakaryocytopoiesis, but no osteogenic activity. Degeneration of the grafts began to occur between days 9 and 13 after implantation. Generally, this was preceded by infection within the chamber, fibroblastic proliferation, and an accumulation of acid mucopolysaccharide in the stroma. The concomitant loss of hemopoiesis and accumulation of acid mucopolysaccharides was consistent with our hypothesis reported previously that excessive concentrations of acid mucopolysaccharide in the hemopoietic microenvironment are not conducive to supporting hemopoiesis, especially erythropoiesis. Degeneration of the grafts probably was the result of infection since there was no evidence of an immunologic response to the graft, and in chambers not containing grafts, similar infections and changes in the connective tissue were observed. The technique of grafting marrow into the hamster cheek pouch chamber provides a model for long-term, in vivo microscopic study of bone marrow. However, methodologic improvements, especially in the control of infections, are needed.

Animals↗
PubMed1992

[Malignant lymphomas in spleen--morphology and microenvironment].

The different entities of malignant lymphomas in the spleen exhibit characteristic stage-dependent infiltration patterns which, in conjunction with cytologic findings, may be employed for diagnostic purposes. These infiltration patterns result from complex interactions between neoplastic and non-neoplastic splenic cell populations which are only incompletely understood. These interactions are governed by intrinsic properties of the involved cell populations, e.g. surface receptors, proliferation activity, cytokine production, immunocompetence etc., as well as by extrinsic factors, e.g. splenic microanatomy and the behavior of splenic immunocompetent and accessory cells which are responsible for the highly organized splenic microenvironments.

Diagnosis, Differential↗
PubMed2003

[Effects of long-term installation of intrauterine devices on intrauterine microenvironment].

OBJECTIVES: To study the effect of long-term installation of intrauterine devices (IUD) on the intrauterine microenvironment. METHODS: Eighty-nine healthy 26 - 50-year-old women undergoing physical examination or having their IUD removed were recruited. Among them 62 had used IUDs, including 32 inert IUD (I-IUD) and 30 copper releasing IUD (T-IUD), for 5 - 20 years, and 27 women without installation of IUD were used as controls. In the 3rd to 13th day of menstrual cycle, 3 ml of irrigation of intrauterine cavity were collected to examine the concentrations of tumor necrosis factor-alpha (TNF-alpha), interleukin 2 (IL-2) and secretary IgA (SIgA) by radioimmunoassay (RIA). Hysteroscopy was used to obtain 3 pieces of endometrium at the place where the IUD was attached for each subject. Three pieces of endometrium were curretted from each control during the proliferative stage. Thirty specimens of endometrium, including 10 cases with I-IUD, 10 cases with T-IUD, and 10 control cases were used to examine the distribution of T cell subset by immunohistochemistry. Fifteen specimens of endometrium, including 6 cases with I-IUD, 6 cases with T-IUD, and 3 control cases, were used to examine the endometrial ultrastructure by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Twenty-five specimens of endometrium, including 10 cases with I-IUD, 10 cases with T-IUD, and 5 control cases, were used to detect the expression and mutation of P16, P53 and K-ras by PCR-SSCP technique. RESULTS: There was no significant difference in TNF-alpha level in the irrigation among the three groups (P > 0.05). IL-2 and SIgA levels (0.39 +/- 0.18) microg/L and (2000 +/- 1224) microg/L respectively) in the T-IUD group were significantly lower than those in the control group (0.96 +/- 0.15) microg/L and (3377 +/- 1906) microg/L respectively, both (P < 0.05). There was a significant difference in the population of T lymphocytes (CD(8)(+) and CD(4)(+) lymphocytes) between the T-IUD group and control group (P < 0.05). SEM and TEM showed no necrosis and atypia in the endometrial cells of I-IUD group and T-IUD group. There was no positive expression of gene p16, p53 and K-ras in the endometrium of the three groups. CONCLUSION: It is safe and effective using I-IUD or T-IUD for a long time, however, T-IUD has some effects on intrauterine local immune function.

Adult↗
PubMedDate not supplied

Transforming growth factor-beta is not the major soluble immunosuppressor in the microenvironments of human breast tumours.

The immunosuppressive nature of the human breast cancer microenvironment was investigated. The soluble fraction of individual tumours was tested for its ability to influence the activation of peripheral blood lymphocytes (PBL) by interleukin-2 (IL-2) and to effect the continued proliferation of cells which had been pre-activated with IL-2. In all cases, both assays were profoundly inhibited (90-100%). None of this inhibition was due to cell killing by the tumour-derived soluble material (TDS). Sixty-two percent of TDS tested contained measurable transforming-growth factor-beta (TGF-beta) activity; following acidification TGF-beta was present in all TDS. However, in neither case was this material present in sufficient amounts to account for the degree of inhibition observed. In addition, neutralisation experiments failed to demonstrate consistent relief of inhibition in the presence of excess anti-TGF-beta antisera. These results demonstrate that TGF-beta s are not the major soluble immunosuppressive materials within human breast tumours.

Breast Neoplasms↗
PubMed1992

[Changes of microenvironment and tumor cell heterogeneity--consequences for bioptic diagnosis].

During the last several decades, immunohistochemical studies of tumors, along with other approaches, have suggested that the clinical and biological progression results, at least in part, from the sequential appearance within the neoplasm of cellular subpopulations whose new characteristics reflect specific somatic genetic changes. However, CNS may provide a different microenvironment for activation and proliferation than other tissues. The tissue-specific distribution of intermediate filament proteins, in particular the keratins, permits their use as marker in histopathology, but several important exceptions are recognized. In this connection, it is of interest that, according to the other reports, glial tumors may be positive for different anti-keratin antibodies. However, the gliomas did not show an immunoreaction in any of the cases when HEA-125 and Ber-EP4 were applied. The great number of multihormonal pituitary adenomas and possible change of the immunohistochemically detectable hormone status in cases of recurrent tumors have particularly re-emphasized the need for new thinking about patterns of classification. The diagnosis of malignant melanoma has been considerably facilitated recently by the introduction of immunohistological labelling with antibodies selective against melanoma antigen (HMB-45). Our results confirmed the necessity of cautious interpretation of HMB-45 immunoreactivity because a HMB-45 expression can be observed in several non-melanotic tumors.

Adenoma↗
PubMed1992

Follicular dendritic cells in the alternative antigen transport pathway: microenvironment, cellular events, age and retrovirus related alterations.

Follicular dendritic cells (FDC) are located in lymphoid follicles of secondary lymphoid tissues and play a pivotal role in the initiation and maintenance of the secondary antibody response. FDC are an integral part of the microenvironment of the follicle and function as members of the 'alternative antigen transport pathway.' This pathway consisting of the antigen transport cell-FDC-ICCOSOME-B cell axis, leads to the formation of germinal centers where antibody-forming cell and memory B cell development are initiated through interaction of FDC-retained antigen, B cells and T helper cells. Evidence suggests that these interactions are down-regulated through antibody feedback, or as needed, reactivated with the utilization of FDC-retained antigen for the maintenance of antibody levels. Age- and retrovirus-related FDC defects seriously compromise the capacity of this pathway to maintain immunity.

Aging↗
PubMed2003

A workshop on the marrow microenvironment and hematological malignancy.

The Division of Cancer Biology of the National Cancer Institute hosted a workshop on hematological malignancies and the marrow microenvironment in Rockville, Maryland in the fall of 2002. There were 22 invited participants from the United States, Canada, and Europe, and the workshop was organized into disease-specific sessions. The sessions were designed to explore the basic science and therapeutic applications related to the stromal and nonstromal components of the marrow in malignant hematological diseases.

Animals↗
PubMed2003

Expression of matrix metalloproteinases in the microenvironment of spontaneous and experimental melanoma metastases reflects the requirements for tumor formation.

Expression of matrix metalloproteinases (MMPs) and their activation in tumor cells, as well as tumor surrounding stromal cells have been implicated in tumor cell invasion and metastasis. By means of a syngeneic tumor model for either experimental or spontaneous metastases, the differential expression of MMPs and tissue inhibitors of MMPs (TIMPs) in relation to the microenvironment and the way of metastasis induction was characterized. In vitro characterization revealed that increased levels of secreted MMP-2, MMP-9, and TIMP-1 were only detectable in the most aggressive cell line, B16G3.12BM2. Remarkably, active MMP-2 was restricted to this cell line, whereas TIMP-2 and membrane type (MT) 1-MMP expression was comparable in all three of the spontaneously metastasizing melanoma cell lines investigated. In vivo analysis demonstrated that MMP-2, MMP-9, and MT1-MMP were predominantly expressed at the tumor-stroma border of s.c. tumors. Furthermore, functional active MMP-2 was restricted to this invasive front. In spontaneous lymph node or lung metastases, however, MMP-9 was expressed both in the center and the periphery of tumors; these areas were largely negative for MMP-2 and MT1-MMP. Notably, tumor cells of experimental lung metastases did not express MMP-9 at all. These results indicate that expression of MMPs in melanoma metastases is not only influenced by their localization but also the nature of tumor induction, suggesting that individual MMPs serve specific roles during the different stages of metastasis formation.

Animals↗
PubMed1992

Composition and functional integrity of the in vitro hemopoietic microenvironment in acute myelogenous leukemia: effect of macrophage colony-stimulating factor.

In the present work, we have investigated the composition and hemopoietic supportive capacity of eleven normal and six acute myelogenous leukemia (AML) marrow-derived stromal adherent layers, established in the absence or in the presence of recombinant human colony-stimulating factor 1 (rhCSF-1, macrophage colony-stimulating factor). Two of six AML adherent layers were deficient in composition (i.e., no confluency, reduced numbers of macrophages and fibroblastic progenitors, and no fat cell formation), resulting in reduced CSF-1 production and a poor hemopoietic supportive capacity (assessed by the ability of an irradiated stroma to sustain the growth of myeloid, erythroid, and multipotential progenitors derived from a second innoculum of normal bone marrow). Four out of six AML adherent layers showed levels of macrophages, fibroblastic progenitors, fat cells, and CSF-1 similar to those observed in adherent layers from normal bone marrow; however, their capacity to sustain normal hemopoiesis was still significantly reduced. The deficient hemopoietic supportive capacity of all AML adherent layers correlated with the presence of a soluble activity in the culture supernatant that inhibited hemopoietic colony formation. Addition of rhCSF-1 during the establishment of AML adherent layers significantly increased their hemopoietic supportive capacity. In contrast, the hemopoietic supportive capacity of normal adherent layers was reduced by rhCSF-1. The opposite effects of rhCSF-1 on the hemopoietic supportive capacity of normal and AML adherent layers correlated with the levels of the soluble inhibitory activity, that is, increased levels in cultures containing rhCSF-1-treated normal adherent layers, and slightly reduced levels in cultures of rhCSF-1-treated AML layers. These results indicate that, despite a morphologically normal composition in most cases (four out of six), the hemopoietic microenvironment developed in long-term marrow culture (LTMC) from all AML marrows analyzed has a deficient hemopoietic supportive capacity, due, at least in part, to the production of hemopoietic inhibitor(s). Such a deficiency can be partially overcome by establishing the stroma layers in the presence of rhCSF-1.

Bone Marrow↗
PubMed2003

[Regulating effect of pineal gland peptides on development of T-lymphocytes in CBA aging mice: role of microenvironment of immune system organs and neuroendocrine factors].

Studies were undertaken on the development of T-lymphocytes in adult and old CBA mice and its changes at aging after injections of pineal gland peptides. It was shown that in old mice the disturbances of T-cells differentiation are registered in bone marrow, thymus, spleen and characterized by the changes of lymphocyte markers expression, migration and proliferation of cells. In old mice FTS titer, melatonin and testosterone levels decreased, the balance of noradrenalin and serotonin in hypothalamus and the cell composition of microenvironment immune systems organs impaired. After chronic (18 mo) administration of the pineal gland preparation epithalamin the amount of stromal cells-precursors, CD4+ and Mac-1(+)-cells in old bone marrow increased, improved the migration of T-cell precursors from bone marrow to thymus and their proliferative potential. The proportion of CD3+, CD4+CD8-, CD4-CD8+, Mac-1(+)-cells in old thymus increased, while that of CD44(+)-cells decreased. The proportion of CD4-CD8(+)-cells in spleen increased. The most number of indices and their balance showed a pattern of adult mice. In old mice after epithalamin the balance of amines in hypothalamus improved, concentration of melatonin in pineal gland, testosterone and FTS titer in blood increased. Epithalon has also the possibility to increase of thymic endocrine function.

Aging↗
PubMed2004

Locoregional immunotherapy of malignant ascites from gastric cancer using DTH-oriented doses of the streptococcal preparation OK-432: Treatment of Th1 dysfunction in the ascites microenvironment.

Locoregional administration of the streptococcal preparation OK-432 is effective in treating malignant ascites from gastric cancer. In order to enhance the efficacy, we conducted a pilot study of locoregional immunotherapy for malignant ascites using host-oriented doses of OK-432. Moreover, action mechanisms of OK-432 were further explored in view of the T-helper type 1 (Th1)-Th2 concept. Gastric cancer patients with cytologically determined malignant ascites were locoregionally administered with OK-432. The dose of OK-432 was selected according to the delayed-type hypersensitivity (DTH) reaction levels to OK-432. Cytokine production profiles of ascites cells were determined using whole ascites assay by stimulation with OK-432. IL-10 mRNA expression was analyzed using RT-PCR. It was found that a positive clinical response was observed in 37 of the 51 (73%) patients with the DTH-oriented approach, showing a significantly higher efficacy than traditional dosage methods using empirical doses (31/58, 53%) (p=0.0487). The DTH-oriented administration of OK-432 produced adverse effects such as fever elevation (p<0.0001) and abdominal pain (p=0.0013) to a significantly lesser extent compared with the traditional treatment. Analysis of the action mechanism of OK-432 revealed that the DTH reaction in responders (19+/-6 mm) was stronger than that in non-responders (6+/-4 mm) (p<0.0001). Tumor necrosis factor (TNF)-alpha production of ascites cells was also higher in responders (3943+/-1247 pg/ml) than in non-responders (1217+/-939 pg/ml) (p=0.0002). There was a significant positive correlation (p=0.0085) between the levels of DTH reaction and TNF-alpha production of ascites cells, but not of blood cells. Responders appeared to polarize on the Th1 axis when clinical responses were plotted on Th1-Th2 dimensions according to the cytokine production profiles of TNF-alpha, IFN-gamma, IL-4 and IL-6 of ascites cells. In vitro culture with IL-2 of ascites cells after OK-432 administration demonstrated an almost clonal expansion of CD4+ lymphocytes, which produced TNF-alpha and IFN-gamma, but did not produce IL-4 or IL-6. IL-10 mRNA expression was detectable in ascites cells from non-responders before treatment. These results suggest that the DTH-oriented locoregional administration of OK-432 may be both effective and less toxic in treating malignant ascites from gastric cancer, showing a possibility of the tailored immunotherapy for malignant ascites. Th1 dysfunction exists in the microenvironment of malignant ascites from gastric cancer, in which IL-10 may, in part, play a role. The up-regulation of Th1 responses by OK-432 may result in positive clinical responses. The DTH reaction to OK-432 may be a useful tool not only for predicting clinical response but also for selecting the optimal dose of OK-432.

Aged↗