Low molecular weight immunosuppressive factors found in elevated amounts in cancer ascitic fluids of mice. 2. 1-Methyladenosine isolated from cancer ascitic fluids enhances Listeria infection in mice

Cysteine Supplementation Mitigates the Toxicity Associated with Antitumor Therapy of Ehrlich's Ascites Fluid Adsorbed over Protein A Containing Staphylococcus aureus Cowan I

Introduction:

Previously, we have reported the amelioration of ad-AF induced hepatotoxicity with the exogenous supplementation of glutathione (GSH) without compromising the anti-tumor effect of ad-AF in ascites tumor model of mice with transplantable Ehrlich’s Ascites Tumor cells. Cellular uptake of glutathione (GSH) has its own limitations, therefore exogenous supplementation of L-cysteine (Cys) was tried to reduce the toxicity of ad-AF by providing –SH contents without compromising the anti-tumor property of adsorbed ascites fluid (ad-AF).

Results:

A significant increase in mean survival time (MST) of tumor bearing mice from 18.1 days to 32.9 days with exogenous supplementation of Cys was observed. Cys supplementation did not alter decline in body-weight gain, tumor cell counts as well as decrease in the viability of tumor cells in ascites tumor bearing animals. Similarly, Cys has been helpful to restore the hepatic –SH contents upto the levels of –SH content in tumor control group. The exogenous supplementation of Cys along with ad-AF has been helpful to restore the decline in the activities of phase-I and enhanced levels of glutathione-S-transferase (GST). The changes in the activities of different enzymes of phase-I and phase-II indicate the reduction in toxic insult induced by the therapeutic material (ad-AF). However, ad-AF treatment could not prevent tumor bearers from natural death due to tumor progression but significantly reduced the rate of tumor progression.

Conclusions:

Our study suggests that exogenous supplementation of Cys alongwith ad-AF could have a potential to be developed as a modality for the treatment of ascites tumor at least at experimental level.

Exogenous supplementation of N-acetylcysteine Can Reduce Hepatotoxicity Induced by Ascites Fluid (Cell-Free) Adsorbed Over Protein-A-Containing Staphylococcus aureus Cowan-I Without Compromising Its Antitumor Effect

Introduction:

Hepatotoxicity along with enhanced mortality has remained a major concern during the development of antitumor therapy with the use of cell-free ascites fluid adsorbed (ad-AF) over Protein-A-containing Staphylococcus aureus Cowan I (SAC). Major issue with ad-AF inoculation is the significant depletion of hepatic glutathione (GSH). Exogenous supplementation of –SH contents to the host has offered an encouraging hope to explore the possibilities to use ad-AF as a therapeutic material due to its antitumor effects. GSH and l-cysteine have shown a promise with the recovery of –SH contents as well as the recovery of phase I and phase II biotransformation enzymes. Aforementioned observations prompted us to try other –SH donors.

Materials and Methods:

Therefore, in this study, N-acetylcysteine (NAC) was used as an exogenous source to provide –SH contents to reduce hepatotoxicity and mortality induced by ad-AF treatment.

Results:

Exogenous supplementation of NAC along with ad-AF treatment to ascites tumor bearers has shown a significant protection against hepatotoxicity and mortality caused by ad-AF. NAC substitution along with ad-AF has significantly enhanced the mean survival time (MST), without altering the antitumor effect of ad-AF as evident from tumor cell counts and viability.

Discussion:

NAC supplementation has been successful to recover hepatic –SH contents along with the significant recovery of phase I and phase II biotransformation enzymes. Marker enzymes for liver injury have also given clear-cut indications for the recovery of tumor bearers from hepatotoxicity induced by ad-AF.

Conclusion:

This study has shown that exogenous supplementation of NAC protects the host from the enhanced mortality and hepatotoxicity induced by ad-AF. These observations offer a hope to develop ad-AF as one of the probable treatment strategies for ascites tumors at least at experimental levels.

The Polarization of M2b Monocytes in Cultures of Burn Patient Peripheral CD14+ Cells Treated with a Selected Human CCL1 Antisense Oligodeoxynucleotide

M2b macrophages (Mφ) play a major role in the increased susceptibility of subacutely burned patients, to sepsis stemming from enterococcal translocation. Certain opportunistic infections in severely burned mice have been controlled by murine CCL1 antisense oligodeoxynucleotide (ODN), a specific polarizer of mouse M2bMφ. In the present study, we have screened CCL1 antisense ODN, which is active against human M2bMφ. Among the 20 CCL1 antisense ODNs synthesized in our laboratory, HCA-11 was shown to be the most active polarizer for human CCL1⁺CD163⁺CD14⁺ cells. Burn patient CCL1⁺CD163⁺CD14⁺ cells (3 × 10⁵ cells/mL) switched to quiescent CCL1^-CD163^-CD14⁺ cells within 48 h in cultures supplemented with 100 μg/mL of HCA-11. After treatment with a 25 μg/chimera dose of HCA-11, the bacterial growth was not observed in various organs of patient chimeras (γNSG mice inoculated with burn patient WBCs) infected with a lethal dose of Methicillin-resistant Staphylococcus aureus. The host antibacterial defenses against certain opportunistic pathogens should be improved in severely burned patients treated with a human CCL1 antisense ODN, HCA-11.

Orosomucoid 1 drives opportunistic infections through the polarization of monocytes to the M2b phenotype. Cytokine. 2015;73:8-15. [PMID: 25689617 DOI: 10.1016/j.cyto.2015.01.017]

Orosomucoid (ORM, composed of two isoforms, ORM1 and ORM2) has been described as an inducer of M2 macrophages, which are cells that decrease host antibacterial innate immunities. However, it is unknown which phenotypes of M2 macrophages are induced by ORM. In this study, healthy donor monocytes stimulated with ORM (ORM-monocytes) were characterized phenotypically and biologically. CCL1 (a biomarker of M2b macrophages) and IL-10 were detected in monocyte cultures supplemented with ORM1; however, CCL17 (a biomarker of M2a macrophages) and CXCL13 (a biomarker of M2c macrophages) were not produced in these cultures. All of these soluble factors were not detected in the culture fluids of monocytes stimulated with ORM2. Monocytes stimulated with ORM1 were characterized as CD64(-)CD209(-)CD163(+)CCL1(+) cells. MRSA and Enterococcus faecalis infections were accelerated in chimeras (NOD/scid IL-2Rγ(null) mice reconstituted with white blood cells) after inoculation with monocytes stimulated with ORM1 or treatment with ORM1; however, the infections were greatly mitigated in both chimeras inoculated with ORM1-stimulated monocytes and treated with ORM1, after an additional treatment with an inhibitor of M2b macrophages (CCL1 antisense ODN). These results indicate that ORM1 stimulates quiescent monocytes to polarize to M2b monocytes. The regulation of M2b macrophages may be beneficial in controlling opportunistic infections in patients with a large amount of plasma ORM1.

Acceleration of R5 HIV replication by polymorphonuclear neutrophils in cultures of macrophages

Cell-to-cell contact between monocyte-derived macrophages (MDM) and endothelial cells has resulted in the increased proliferation of CC chemokine receptor 5/M-tropic (R5) human immunodeficiency virus (HIV) in MDM. In the present study, R5 HIV replication was shown to be increased by polymorphonuclear neutrophils (PMN) in MDM cultures through the soluble factors released from these PMN. The replication of R5 HIV in MDM was greatly enhanced when PMN were added to cultures. An increase in the replication of R5 HIV was also demonstrated when the virus was replicated in MDM cultured in a double chamber transwell with PMN. Chemokine ligand (CCL) 2 and interleukin (IL)-10 were detected in culture fluids of PMN exposed to R5 HIV. The replication of R5 HIV was not accelerated in cultures of MDM and PMN in a double chamber transwell supplemented with a mixture of monoclonal antibodies directed against CCL2 and IL-10. Similarly, the replication of R5 HIV was accelerated in MDM cultures supplemented with a mixture of recombinant CCL2 and IL-10. These results indicated that, in response to the viral stimulation, PMN produce CCL2 and IL-10 and enhance the replication of R5 HIV in MDM cultures.

Glycyrrhizin Inhibits R5 HIV Replication in Peripheral Blood Monocytes Treated with 1-Methyladenosine

R5 HIV replicated in freshly isolated human peripheral blood monocytes after treatment with 1-methyladenosine (fresh PBM/MA), an immunosuppressive compound isolated from tumorous ascites fluids, while viral replication was not demonstrated in untreated peripheral blood monocytes (fresh PBM). The R5 HIV replication in fresh PBM/MA was inhibited by glycyrrhizin (GL). Without any other stimulation, fresh PBM/MA produced CCL2 and IL-10, while these soluble factors were not released from fresh PBM. GL greatly inhibited the production of CCL2 and IL-10 in fresh PBM/MA. After treatment with CCL2 and/or IL-10, CCR5 mRNA expression in fresh PBM was markedly enhanced, while only a trace level of the mRNA expression was detected in these cells in the absence of CCL2 or IL-10. CCR5 mRNA expression in fresh PBM treated with CCL2 or IL-10 was clearly inhibited by GL. These results indicate that GL inhibits R5 HIV replication in fresh PBM/MA through the inhibiting CCR5 expression mediated by CCL2 or IL-10.

Cytokine production by rabbit alveolar macrophages: differences between activated and suppressor cell phenotypes

The differences between cytokine-producing profiles of activated macrophages (A-M phi) and suppressor macrophages (S-M phi) were examined. A-M phi, which exhibited cytotoxicity against RK-13 cells, were generated from resident rabbit alveolar M phi by treatment with lymphokine solution (culture fluids of rabbit spleen cells stimulated with concanavalin A [Con A]). S-M phi, which were able to inhibit cellular proliferations of rabbit spleen cells stimulated with Con A, were generated from resident alveolar M phi by treatment with 1-methyladenosine (an immunosuppressive molecule in tumourous ascites fluids). When A-M phi were stimulated with lipopolysaccharide (LPS) in vitro, the cells produced significantly more interleukin (IL)-1 (approximately 1.4 times), IL-6 (approximately 2.1 times), IL-12 (approximately 60 times), and tumour necrosis factor-alpha (TNF-alpha) (approximately 37 times) than did resting macrophages (R-M phi) stimulated with LPS as control cells. After the stimulation with LPS, both A-M phi and R-M phi did not produce transforming growth factor-beta (TGF-beta). In contrast, when S-M phi were stimulated with LPS in vitro, the cells produced significantly more TGF-beta (approximately 1.6 times) and significantly less IL-6 (approximately 1.8 times) than did control cells. Also, S-M phi did not produce IL-1, IL-12, and TNF-alpha into their culture fluids after the stimulation with LPS. These results show the differences between cytokine-producing profiles of A-M phi and S-M phi, and characteristics of their cytokine-producing profiles are analogous to T cell subsets. Differences displayed in the cytokine profiles may contribute to the effector (A-M phi) or the suppressor (S-M phi) functions of alveolar M phi.

Glutathione reduces the toxicity associated with antitumor therapy of ascites fluid adsorbed over Staphylococcus aureus Cowan I in tumor bearing mice

It has been well documented in the literature that the removal of circulatory immune complexes (CICs) from the host circulation leads to the immunopotentiation as well as generation of antitumor responses in a variety of tumors in rats, cats, dogs and human patients. CICs are the major immunosuppressive factors in tumor bearing host. Protein A (PA) has been extensively used for the removal of these CICs from the sera/plasma of tumor bearers, because PA has the ability to bind with the Fc portion of mammalian immunoglobulins. Previously, we reported for the first time a potent antitumor response by the inoculation of cell free Ehrlich's ascites fluid adsorbed in vitro over PA containing Staphylococcus aureus Cowan I (SAC) in Ehrlich's ascites tumor model. However, there was toxicity associated with this form of therapy in terms of early death of treated animals and the depletion of hepatic glutathione pool as well as phase I biotransformation enzyme and increase in glutathione-S-transferase (GST) activities. In the present investigation, tumor bearing animals were treated intraperitoneally (i.p.) on alternate days for 15 days with adsorbed ascites fluid (ad-ASF) (0.1 ml) and glutathione (GSH) (250 mg/kg body weight) separately. We found that GSH supplementation increases mean survival time of GSH and ad-ASF treated mice up to 37.2 days in comparison with 19.9 days for only ad-ASF treated animals, while percent increase in body weight was found to be not affected by the GSH substitution, which remains significantly lower (P < 0.01) in comparison to the tumor control animals. GSH supplementation causes a significant decrease (P < 0.05) of glutathione-S-transferase and restoration of aniline hydroxylase activity (P < 0.05) and aminopyrine-N-demethylase activity. We have also observed that GSH supplementation does not alter the tumor cell viability and tumor cell counts in ad-ASF treated animals in comparison to only ad-ASF treated animals, which indicates that GSH supplementation does not alter the antitumor effect of the therapy. Treatment of Ehrlich's ascites tumor bearing mice with ad-ASF and glutathione increased their survival, but did not reduce the mortality of animals because of tumor.

Ehrlich's ascites fluid adsorbed over protein A containing Staphylococcus aureus Cowan I produces inhibition of tumor growth

Our earlier studies have shown that removal of various blocking factors from the sera of tumor-bearing animals and humans by adsorption over heat-attenuated and formalin-fixed-Staphylococcus aureus Cowan I (SAC) containing Protein A (PA) causes antitumor immune response. It was also shown that this procedure caused regression of a wide variety of established animal and human tumors. In the present investigation, the therapeutic potential of inoculation of ascites fluid adsorbed in vitro over non-viable SAC containing PA has been demonstrated in Ehrlich' s ascites tumor (EAT) in mouse. The antitumor effect was evident by a significant decrease in body weight (p<0.001) as well as significant reduction in viability of ascites tumor cells (p<0.001) in peritoneal cavity. However, some of the responding animals died earlier than controls, this may be due to the toxicity associated with therapy. The toxic effects were evident in decreased contents of glutathione, and increased activity of glutathione-S-transferase, decreased activity of microsomal enzymes and also in an early death of some of tumor regressed animals. The probable causes of toxicity of the therapy and prospects of reversing these toxic effects are discussed.

Polysaccharide (ANK-102) from Polianthes tuberosa cells deteriorates the resistance of mice to Listeria monocytogenes infection

Modulatory effect on the murine self defense system by a newly discovered acidic polysaccharide (ANK-102) produced by P. tuberosa cells in liquid culture was examined. Pretreatment with ANK-102 deteriorated the murine survival against lethal infection of Listeria monocytogenes, an intracellular gram-positive bacterium eliminated mainly by macrophages through T-cell mediated immune response. Pretreatment with ANK-102 resulted in the accumulation of Mac 1 and Mac 2 positive cells in the peritoneal cavity of the infected animals and the reduction of Thy1.2 expression on the surface of the thymocytes. A new type of immunosuppressive polysaccharide ANK-102 was introduced.

Immunochemical detection of urinary 5-methyl-2'-deoxycytidine as a potential biologic marker for leukemia

A monoclonal antibody against 5-methylcytidine was prepared and characterized. This antibody, termed AMC, was reactive with compounds that had 5-methylcytosine structure (i.e. 5-methyl-2'-deoxycytidine, 5-methylcytidine and 5-methylcytosine). AMC had the highest reactivity to 5-methyl-2'-deoxycytidine among reactive compounds and had no or very slight cross-reactivity to cytidine-related compounds and any other compounds. Analysis of immunoreactive materials in urine revealed that 5-methyl-2'-deoxycytidine rather than 5-methylcytidine was, contrary to our expectation, the major component. Then the inhibition ELISA system using AMC was established and urinary levels of 5-methyl-2'-deoxycytidine in healthy individuals and cancer patients were determined. The mean excretion levels of healthy individuals was 0.90 +/- 0.43 nmol/mumol creatinine and the cut-off value was set at the mean + 2 S.D. of healthy individuals (1.76 nmol/mumol creatinine). Among various types of cancer tested, elevated levels of 5-methyl-2'-deoxycytidine were detected in leukemia patients. From these results, urinary 5-methyl-2'-deoxycytidine might be applicable as a biologic marker for leukemia.

Relationship of urinary pseudouridine and 1-methyladenosine to activity of leukemia and lymphoma

Urinary levels of pseudouridine and 1-methyladenosine in patients with leukemia and lymphoma were measured by the inhibition ELISA using monoclonal antibodies to determine the correlation of nucleosides excretion with disease activity. Significantly elevated levels of these nucleosides were detected in patients with all types of disease tested. Seventy-seven percent (46/60) and 62% (37/62) of patients had elevated levels of pseudouridine and 1-methyladenosine above normal mean + 2S.D., respectively, and combination assay of these nucleosides gave higher positive rate (87%; 52/60) than either single assay. The changes of urinary pseudouridine and 1-methyladenosine reflected the disease status of patients in remission or in relapse and the effect of chemotherapy. These results suggest that urinary pseudouridine and 1-methyladenosine might be clinically useful as complementary markers to the monitoring of the disease status of patients with leukemia and lymphoma by hematological examination.

Detection of elevated amounts of urinary pseudouridine in cancer patients by use of a monoclonal antibody

Preparation of anti-pseudouridine monoclonal antibodies (MoAbs) and their applications for the quantitation of urinary pseudouridine in cancer patients are described. Seven MoAbs were selected. Five MoAbs were specific for pseudouridine and two MoAbs were cross-reactive with uridine. The most specific antibody, APU-6, was used in an enzyme-linked immunosorbent assay (ELISA) to determine urinary pseudouridine. Sensitivity was in the picomole range and the accuracy was nearly equal to that of the high performance liquid chromatography (HPLC) assay. The amount of pseudouridine in the urine of 28 healthy donors was 31.17 +/- 9.94 nmol/mumol creatinine. In 55% (35/63) of patients with cancer, urinary pseudouridine was elevated above the normal mean + 2 SD (51.04 nmol/mumol creatinine). Particularly, all of the patients (15/15) with leukemia and lymphoma had elevated levels of pseudouridine. These results suggest that urinary pseudouridine might be useful as a marker for leukemia and lymphoma.

Plasma ultrafiltration as successful therapy of rabbit VX-2 carcinoma

It has been demonstrated that tumor-bearing animals elaborate a low molecular weight (less than 10,000 daltons) factor capable of inhibiting in vitro lymphocyte function. It was postulated that removal of this factor would have a favorable effect on host immune response that would translate into improved tumor control. A study was conducted in rabbits bearing the VX-2 carcinoma. Ultrafiltration (UF) was performed 10 days following IV tumor inoculation. UF was achieved by passing blood through an Amicon Diafilter (molecular weight cutoff 10 kD) positioned between the arterial and venous cannulae after heparinization. Two plasma volumes of ultrafiltrate were removed with continuous saline replacement. Two groups of animals received the nonspecific immunoadjuvant, Detox, at time of therapy. Survival in the UF group (N = 9) was compared to untreated tumor-bearing animals (N = 10), sham-operated animals (N = 6), animals receiving Detox (N = 7), and animals receiving UF plus Detox (N = 6). UF imparted a survival advantage when compared to controls (mean 35 days vs. 25 days, P less than .01). The sham group had survival identical to controls. Detox alone conferred minimal survival advantage (mean 29 days, P greater than .05). However, UF + Detox demonstrated maximal survival benefit (mean 40 days, P less than .01). We conclude that UF is an effective anticancer modality in this preclinical model. This study suggests that efforts aimed at eliminating suppressor molecules in cancer patients may be of benefit, especially when combined with biological response modifiers such as Detox.

Preparation of a monoclonal antibody specific for 1-methyladenosine and its application for the detection of elevated levels of 1-methyladenosine in urines from cancer patients

A monoclonal antibody specific for a modified nucleoside, 1-methyladenosine, was prepared and characterized. This antibody, termed AMA-2, reacts with 1-methyladenosine and 1-methyladenine but not with other nucleosides, particularly methylated adenosines other than 1-methyladenosine and methylated guanosines, tested in this investigation. In our experiments, AMA-2 was used in an enzyme-linked immunosorbent assay (ELISA) system for the quantitation of the levels of 1-methyladenosine in urine. Sensitivity was in the picomole range and accuracy was nearly equal to that of the high-performance liquid chromatography (HPLC) assay system. Urinary levels of 1-methyladenosine in healthy donors and patients with various advanced cancers were determined by the inhibition ELISA. The amount of 1-methyladenosine in urine of 33 healthy donors was 1.91 +/- 0.66 nmol/mumol creatinine. In 54% (51/94) of patients, urinary 1-methyladenosine was elevated above the mean plus 2 standard deviations for the healthy donors (3.23 nmol/mumol creatinine). In patients with leukemia, esophageal cancer, stomach cancer, colon cancer, and bladder cancer, urinary levels of 1-methyladenosine were significantly elevated. In patients with leukemia, urinary 1-methyladenosine levels changed almost in parallel with the change in the clinical response during chemotherapy. These results suggest that urinary 1-methyladenosine might be useful in monitoring the effectiveness of therapy.