Outcomes from a mechanistic biomarker multi-arm and randomised study of liposomal MTP-PE (Mifamurtide) in metastatic and/or recurrent osteosarcoma (EuroSarc-Memos trial)

The phase III clinical study of adjuvant liposomal muramyl tripeptide (MTP-PE) in resected high-grade osteosarcoma (OS) documented positive results that have been translated into regulatory approval, supporting initial promise for innate immune therapies in OS. There remains, however, no new approved treatment such as MTP-PE for either metastatic or recurrent OS. Whilst the addition of different agents, including liposomal MTP-PE, to surgery for metastatic or recurrent high-grade osteosarcoma has tried to improve response rates, a mechanistic hiatus exists in terms of a detailed understanding the therapeutic strategies required in advanced disease. Here we report a Bayesian designed multi-arm, multi-centre, open-label phase II study with randomisation in patients with metastatic and/or recurrent OS, designed to investigate how patients with OS might respond to liposomal MTP-PE, either given alone or in combination with ifosfamide. Despite the trial closing because of poor recruitment within the allocated funding period, with no objective responses in eight patients, we report the design and feasibility outcomes for patients registered into the trial. We demonstrate the feasibility of the Bayesian design, European collaboration, tissue collection with genomic analysis and serum cytokine characterisation. Further mechanistic investigation of liposomal MTP-PE alone and in combination with other agents remains warranted in metastatic OS.

Evaluating the antibacterial activity of muramyl dipeptide derivatives, retro-tuftsin derivatives, and anthraquinone oligopeptides against a range of pathogenic bacteria

Search for new and efficient antibiotic is crucial because of microbial drug resistance and problems with side effects of the administered medication. In this study, we evaluate the in vitro microbiological activity of muramyl dipeptide derivatives, retro-tuftsin derivatives (i.e., tuftsin with reversed amino acid sequences), and combinations of retro-tuftsin derivatives with substituted anthraquinones. The potency of the investigated derivatives towards methicillin-sensitive Staphylococcus aureus (MSSA), methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumoniae ESBL (extended-spectrum β-lactamases) was compared based on the spectroscopically-measured minimal inhibitory concentrations (MIC values). The bacterial growth have also been studied with different concentrations of compounds. Statistical analysis of the results revealed that certain modifications lead to promising activity against S. aureus (anthraquinone analogue - 3c and retro-tuftsin derivative - 2b), while other derivatives exhibit activity against P. aeruginosa (muramyl dipeptide derivative - 1d and retro-tuftsin derivative - 2b). The obtained results of microbiological activity indicate that the structure of the tested compounds may be the basis for further modifications.

Differential Peptidoglycan Recognition Assay Using Varied Surface Presentations

Bacterial peptidoglycan (PG) is recognized by the human innate immune system to generate an appropriate response. To gain an appreciation of how this essential polymer is sensed, a surface plasmon resonance (SPR) assay using varied PG surface presentation was developed. PG derivatives were synthesized and immobilized on the surface at different positions on the molecule to assess effects of ligand orientation on the binding affinities of NOD-like receptors (NLRs). NLRP1 and NOD2 are cytosolic innate immune proteins known to generate an immune response to PG. Both possess conserved leucine rich repeat domains (LRR) as proposed sites of molecular recognition, though limited biochemical evidence exists regarding the mechanisms of PG recognition. Here direct biochemical evidence for the association of PG fragments to NOD2 and NLRP1 with nanomolar affinity is shown. The orientations in which the fragments were presented on the SPR surface influenced the strength of PG recognition by both NLRs. This assay displays fundamental differences in binding preferences for PG by innate immune receptors and reveals unique recognition mechanisms between the LRRs. Each receptor uses specific ligand structural features to achieve optimal binding, which will be critical information to manipulate these responses and combat diseases.

Muramyl Tripeptide Plus Chemotherapy Reduces Metastasis in Non-Metastatic Osteosarcoma: A Single-Center Experience

BACKGROUND

The immunomodulator mifamurtide plus a chemotherapy regimen has been shown to significantly improve the outcome in non-metastatic osteosarcoma patients. We report the results of the addition of mifamurtide to chemotherapy in newly diagnosed patients with osteosarcoma.

METHODS

A total of 36 children with osteosarcoma without detectable metastasis were treated between November 2010 and April 2018 at the Ankara University Department of Pediatric Oncology. Mifamurtide was added to the chemotherapy regimen in 17 patients while the remaining 19 did not receive mifamurtide. The probabilities of metastasis and overall survival were compared between the groups.

RESULTS

The 43-month survival rate was 87.5% and 89.9% in the patients who received and did not receive mifamurtide, respectively (p=0.65). Common side effects of mifamurtide were chills and fever. The addition of mifamurtide in the high-risk group with ≤95% necrosis tended to decrease the probability of distant metastasis (36.4% vs. 58.3%) (p=0.39). The time to metastasis in the group with positive surgical margins (4 months in one patient in the non-mifamurtide group, 7 and 20 months in the mifamurtide group) was also longer in the mifamurtide group. During the 43-month follow up period, median time to metastasis was longer in the mifamurtide group (20 vs. 5 months). In addition, mifamurtide plus chemotherapy decreased the risk of metastasis in the cases with primary site relapse.

CONCLUSIONS

The addition of mifamurtide to chemotherapy might improve event-free survival by decreasing the probability of distant metastasis in bad histologic responders, and also by increasing the time to distant metastasis in the surgical margin positive group. Additional clinical studies are necessary to determine the long-term effects of mifamurtide on metastatic disease.
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Sarcome-13/OS2016 trial protocol: a multicentre, randomised, open-label, phase II trial of mifamurtide combined with postoperative chemotherapy for patients with newly diagnosed high-risk osteosarcoma

INTRODUCTION

The controversial results on the mifamurtide efficacy associated with chemotherapy, issued from the American INT-0133-study, in localised osteosarcomas, and the underpowered analysis performed separately in metastatic patients, should be clarified to homogenise international use of this promising drug. The European Commission has granted a marketing authorisation to mifamurtide combined with postoperative chemotherapy in localised osteosarcomas but not in metastatic patients, while the Food and Drug Administration (FDA) has denied this authorisation.

METHODS AND ANALYSIS

Sarcome-13/OS2016 trial is a multicentre randomised open-label phase II trial evaluating the survival benefit of mifamurtide administered during 36 weeks in combination with postoperative chemotherapy versus chemotherapy alone, in patients >2 and ≤50 years with newly diagnosed high-risk localised or metastatic osteosarcoma. The main objective is to evaluate the impact on event-free survival (EFS) of mifamurtide on intention-to-treat population. The secondary objectives are to evaluate the impact of mifamurtide on overall survival, to evaluate the feasibility and toxicity of the planned treatment, to correlate biology/immunology with the mifamurtide efficacy/toxicity. With a total of 126 enrolled patients and 51 events, the power is 80% if mifamurtide is associated with an 18% improvement of the 3-year EFS (52%vs70%, equivalent to an HR=0.55), with a one-sided logrank test alpha=10%. As relevant historical data are available (aggregate treatment effect from the INT-0133 trial and individual data from the control group of the Sarcome-09/OS2006 trial), a Bayesian analysis is also planned.

ETHICS AND DISSEMINATION

This study was approved by the 'Comité de Protection des Personnes Ile de France I' (12/06/2018), complies with the Declaration of Helsinki and French laws and regulations, and follows the International Conference on Harmonisation E6 Guideline for Good Clinical Practice. The trial results, even if they are inconclusive, as well as biological ancillary studies will be presented at appropriate international congresses and published in international peer-review journals.

TRIAL REGISTRATION NUMBER

EudraCT 2017-001165-24, NCT03643133.

In Vitro Synergic Effect of Interferon Gamma Combined with Liposomes Containing Muramyl Tripeptide on Human Monocyte Cytotoxicity Against Fresh Allogeneic and Autologous Tumor Cells

Aims

The purpose of the present study was to investigate whether human recombinant interferon- γ (hrIFN - γ) can act synergically with various activators in increasing the cytotoxicity of cancer patient monocytes against fresh autologous and allogeneic tumor cells.

Methods

Fresh target cells were obtained by means on the mechanical and enzymatic dissociation of human renal carcinomas. A 375 and SW 626 cell lines were used as positive controls. Monocytes from renal cancer patients and normal volunteers were activated in vitro with lipopolysaccharide, muramyl tripeptide (MTP-PE) or liposomes containing MTP-PE (MTP-PE liposomes), with or without a pre-incubation with hrIFN- γ and were tested for cytotoxicity by means of a 72-hr 111indium-release assay. All of the patients were tumor free at the time of the study.

Results

Cancer patient peripheral blood monocytes were activated in vitro by different immunomodulators and became cytotoxic to freshly dissociated autologous or allogeneic tumor cells. A synergic effect producing maximal cytotoxicity was obtained with an appropriately scheduled combination of hrIFN- γ (10 U/ml) and MTP-PE liposomes (50 nm/ml), free lipopolysaccharide (10 μg/ml) or MTP-PE (100 μg/ml). The synergic cytotoxicity was observed against fresh allogeneic and autologous tumor cells, as well as against cultured cells.

Conclusions

All of these data support the possibility of a combined treatment using hrIFN- γ and MTP-PE liposomes in human studies, particularly when it is borne in mind that liposomes can prevent the direct toxicity of many immunomodulators and that the low levels of hrIFN- γ required for the synergic activation are not toxic in vivo.

Soluble Intercellular Adhesion Molecule-1 and Serum Cytokines in Melanoma Patients Treated with Liposomes Containing Muramyl Tripeptide

Aims and Background

A soluble form of intercellular adhesion molecule-1 (sICAM-1) has been recently identified in patients with malignant melanoma. It has been demonstrated that inflammatory cytokines can modulate the cellular expression of ICAM-1 and the shedding of this molecule by cells. To our knowledge, few data exist on serum sICAM-1 levels in cancer patients treated with immunomodulators. Liposomes containing muramyl tripeptide (MLV MTP-PE) can activate monocytes from cancer patients in vitro and in vivo, making them cytotoxic such as tumor necrosis factor- α (TNF-α) and Interleukin-6 (IL-6). The purpose of the present study was to evaluate the levels of sICAM-1 and their possible correlation with serum inflammatory cytokine levels in melanoma patients treated with MLV MTP-PE.

Methods

The sera from 9 patients with metastatic melanoma treated with MLV MTP-PE, 4 mg i.v. twice a week for 12 weeks, were tested in ELISA system to detect sICAM-1, TNF-α, IL-6, Interleukin-1 β (IL- β) and Interferon-γ (IFN-γ) before, and 2 and 24 h after the 1st, 12th and 24th infusion of MLV MTP-PE.

Results

Baseline levels of sICAM-1 were elevated in all patients (median 540 ng/ml: range 400-1030 ng/ml). Twenty-four h after the 1st infusion of MLV MTP-PE, we observed 6 increases in sICAM-1 levels, 1 decrease and 2 stable values (median 720 ng/ml: range 410-1820; P = 0.060). Twenty-four h after the 12th infusion, sICAM-1 increased in 3 patients and did not change in 4 (median 790 ng/ml: range 495-1650 ng/ml; P = 0.069). At the 24th infusion, sICAM-1 increased in 4 of 6 evaluable patients and remained stable in 2 (median 802 ng/ml: range 510-1450 ng/ml; P = 0.045). To better analyze the variations in sICAM-1, the patients were arbitrarily divided into two groups according to their clinical behavior: 4 presented stabilization (all lesions, n = 2; some lesions, n = 2) (Group A); 5 presented progressive disease (Group B). In Group A, sICAM-1 levels remained stable or showed a modest increase during treatment (except in 1 patient, who exhibited a substantial variation after the 12th infusion). In contrast, in Group B very high levels of sICAM-1 were observed at the beginning of the study therapy in 1 patient and after the 1st infusion in 3 patients; these values remained high until the 24th infusion. In most of the patients, TNF-α and IL-6 increased after the 1st infusion, but not thereafter. IFN-γ was never detected; IL-1 β was detectable in a few cases, but only before the infusions.

Conclusions

baseline levels of sICAM-1 were elevated in all patients and further increased during treatment only in patients with more aggressive disease. No correlation was found between sICAM-1 and inflammatory cytokines. It would therefore seem that in patients with advanced disease, higher levels and a progressive increase in sICAM-1 may be unfavorable prognostic factors.

Tunable degradation of acetalated dextran microparticles enables controlled vaccine adjuvant and antigen delivery to modulate adaptive immune responses

Subunit vaccines are often poorly immunogenic, and adjuvants and/or delivery vehicles, such as polymeric microparticles (MPs), can be used to enhance immune responses. MPs can also be used to understand cell activation kinetics and the significant impact antigen and adjuvant release has on adaptive immune responses. By controlling antigen and adjuvant release, we can determine if it is important to have precise temporal control over release of these elements to optimize the peak and duration of protective immunity and improve vaccine safety profiles. In order to study the effect of tunable adjuvant or antigen delivery on generation of adaptive immunity, we used acetalated dextran (Ace-DEX) MPs. Ace-DEX MPs were used because their tunable degradation can be controlled based on polymer cyclic acetal coverage (CAC). Ace-DEX MPs of varying degradation profiles were used to deliver murabutide or ovalbumin (OVA) as a model adjuvant or antigen, respectively. When murabutide was encapsulated within Ace-DEX MPs to test for controlled adjuvant delivery, fast-degrading MPs exhibited higher humoral and cellular responses in vivo at earlier time points, while slow-degrading MPs resulted in stronger responses at later time points. When OVA was encapsulated within Ace-DEX MPs to test for controlled antigen delivery, fast-degrading MPs induced greater antibody and cytokine production throughout the length of the experiment. This differential response suggests the need for distinct, flexible control over adjuvant or antigen delivery and its impact on immune response modulation.

Effectiveness of mifamurtide in addition to standard chemotherapy for high-grade osteosarcoma: a systematic review

BACKGROUND

Osteosarcoma mostly occurs during the period of rapid bone growth in children and adolescents as high-grade osteosarcomas. Current treatment recommended for high-grade non-metastatic and metastatic and/or relapsed osteosarcoma involves neoadjuvant multiagent conventional chemotherapy, followed by surgical resection of macroscopically detected tumor and postoperative adjuvant chemotherapy. However, residual micrometastatic deposits that develop following surgery have shown resistance to postoperative/adjuvant chemotherapy. Therefore, there is a critical need for more effective and innovative therapeutic approaches such as immune stimulatory agents. The most extensively studied immune stimulatory agent in the treatment of osteosarcoma is mifamurtide. The aim of this systematic review was to identify and synthesize the evidence on the effectiveness of mifamurtide in addition to standard chemotherapy on survival outcomes.

OBJECTIVES

To present the best available evidence on the treatment of high-grade non-metastatic and metastatic osteosarcoma with mifamurtide in addition to standard chemotherapy.

INCLUSION CRITERIA TYPES OF PARTICIPANTS

All populations of patients regardless of age, gender or ethnicity with high-grade, resectable, non-metastatic and metastatic osteosarcoma based on histological diagnosis.

TYPES OF INTERVENTIONS AND COMPARATORS

This review focused on intravenous infusion of either of the pharmaceutical formulations of mifamurtide (MTP-PE or L-MTP-PE) in addition to standard chemotherapy, and the comparator was chemotherapy alone.

TYPES OF STUDIES

This review considered any experimental study design including randomized controlled trials, non-randomized trials and quasi-experimental studies.

OUTCOMES

The primary outcomes of interest were event-free survival, overall survival and recurrence of osteosarcoma. Secondary outcomes that were considered included health-related quality of life and any mifamurtide-related adverse events.

SEARCH STRATEGY

A search for published and unpublished literature in English was undertaken (seven published literature databases, four unpublished literature databases, and three government agency and organizational websites were searched). Studies published between 1990 to June 2016 were considered. A three-step strategy was developed using MeSH terminology and keywords to ensure that all relevant studies were included related to this review.

METHODOLOGICAL QUALITY

The methodological quality of included studies was assessed by two reviewers, who appraised each study independently, using a standardized Joanna Briggs Institute (JBI) critical appraisal tool.

DATA EXTRACTION

Data was extracted from the studies that were identified as meeting the criteria for methodological quality using the standard JBI data extraction tool.

DATA SYNTHESIS

Due to the heterogeneity of populations and interventions in available studies, meta-analysis was not possible and results are presented in narrative form.

RESULTS

Three papers outlining two studies involving 802 patients evaluated the effectiveness of mifamurtide in addition of chemotherapy. Results indicated no significant difference in event-free survival between the addition of mifamurtide to standard chemotherapy regimen and chemotherapy alone, both in non-metastatic and metastatic osteosarcoma patients. There was a significant difference in progression-free survival favoring the addition of mifamurtide in pulmonary metastatic and/or relapsed osteosarcoma. There was no significant difference in overall survival between the addition of mifamurtide and chemotherapy alone in metastatic osteosarcoma; however there was a significant difference favoring the addition of mifamurtide in non-metastatic osteosarcoma patients. The addition of mifamurtide resulted in a significant difference in survival after relapse in pulmonary metastatic and/or relapsed osteosarcoma patients. Both studies reported on mifamurtide-related adverse events - the first was reported as toxicity which included haematological, hepatic, renal, gastrointestinal disorders, cardiac, rhythm and nervous system disorders, ear disorders and others (infection, fever; and performance status) in metastatic osteosarcoma patients. Results were similar across all combined treatment regimens. Although no statistical analysis was undertaken, the figures suggest there were no significant differences between the treatment regimens. In the other study, mifamurtide-related adverse events were reported as clinical toxic effects of mifamurtide in relapsed osteosarcoma, which included chills, fever and headache for the initial dose of mifamurtide, while for the subsequent doses of mifamurtide all patients reported toxicity as delayed fatigue.

CONCLUSIONS

The available evidence on the effectiveness of mifamurtide in addition to a standard chemotherapy regimen for the treatment of high-grade osteosarcoma is limited and therefore no definitive conclusions can be made.

Heavy metals produce toxicity, oxidative stress and apoptosis in the marine teleost fish SAF-1 cell line

The use of cell lines to test the toxicity of aquatic pollutants is a valuable alternative to fish bioassays. In this study, fibroblast SAF-1 cells from the marine gilthead seabream (Sparus aurata L.) were exposed for 24 h to the heavy metals Cd, Hg, MeHg (Methylmercury), As or Pb and the resulting cytotoxicity was assessed. Neutral red (NR), MTT-tetrazolio (MTT), crystal violet (CV) and lactate dehydrogenase (LDH) viability tests showed that SAF-1 cells exposed to the above heavy metals produced a dose-dependent reduction in the number of viable cells. Methylmercury showed the highest toxicity (EC50 = 0.01 mM) followed by As, Cd, Hg and Pb. NR was the most sensitive method followed by MTT, CV and LDH. SAF-1 cells incubated with each of the heavy metals also exhibited an increase in the production of reactive oxygen species and apoptosis cell death. Moreover, the corresponding gene expression profiles pointed to the induction of the metallothionein protective system, cellular and oxidative stress and apoptosis after heavy metal exposure for 24 h. This report describes and compares tools for evaluating the potential effects of marine contamination using the SAF-1 cell line.

[The clinical economic analysis of application of immune correcting preparations to prevent respiratory infections and their complications in frequently ill children of early school age]

The article presents the results of clinical economic analysis of effect of different immune correcting preparations on rate of respiratory infections in 548 frequently ill children of early school age. It is established that preventive immune correction with lysates of bacteria or glucosaminyl muramyl dipeptide in aggregate with vitamin mineral complex results in statistically significant decreasing of rate of respiratory infections and dramatic decreasing of direct and indirect costs of treatment of infectious diseases of respiratory ways. The preventive application of juice of cone-flower herb or interferon in aggregate with vitamnin mineral complex statistically significantly decreases rate of respiratory infections and negligibly decreases direct and indirect costs of their treatment.

Mifamurtide for high-grade, resectable, nonmetastatic osteosarcoma following surgical resection: a cost-effectiveness analysis

OBJECTIVES

Mifamurtide is an immune macrophage stimulant that when added to standard chemotherapy has demonstrated survival benefit for newly diagnosed osteosarcoma. The objectives of this study were to investigate the cost-effectiveness of adding mifamurtide to standard three- or four-agent chemotherapy for high-grade, resectable, nonmetastatic osteosarcoma following surgical resection and the issues of obtaining robust cost-effectiveness estimates for ultra-orphan drugs, given the shortage of data.

METHODS

An economic evaluation was conducted from the perspective of the UK's National Health Service as part of the manufacturer's submission to the National Institute for Health and Care Excellence. The disease process was simplified to a transition through a series of health states, modeled by using a Markov approach. Data to inform the model were derived from patient-level data of Study INT-0133, published literature, and expert opinion. The final efficacy measure was life-years gained (LYG), and utilities were used to obtain quality-adjusted life-years (QALYs).

RESULTS

For a 60-year time frame and a discount rate of 3.5% for outcomes, patients receiving mifamurtide benefited from an average additional 1.57 years of life and 1.34 QALYs, compared with patients receiving chemotherapy alone, giving an incremental cost-effectiveness ratio (ICER) of £58,737 per LYG and £68,734 per QALY. Because treatment effects were both substantial in restoring health and sustained over a very long period, the National Institute for Health and Care Excellence changed its guidance to allow a discount of 1.5% for outcomes to be applied in these special circumstances. By using this discount factor, it was found that patients receiving mifamurtide had an average additional 2.58 years of life and 2.20 QALYs compared with patients receiving chemotherapy alone, resulting in an ICER of £35,765 per LYG and £41,933 per QALY.

CONCLUSION

Mifamurtide's ICER is cost-effective compared with that of other orphan and ultra-orphan drugs, for which prices and corresponding cost-effectiveness estimates are high.

[Comparative characteristic of the treatment efficacy in patients with often recurrent acute respiratory infections complicated with immunodeficiency treated with likopid]

It was analysed the fascinating and metabolic phagocytic activity of neutrophilis (cationic-protein, myeloperoxidase and latex tests, NST-test: spontaneous and stimulated, stimulation index) in patients with often recurrent acute respiratory infections on the base of immunodeficiency disorders who received sublingual drug Licopid in dose of 1 mg/daily (30 patients) and 3 mg/daily (30 patients) during 14 days. It was found that Licopid in the daily dose of 3 mg could lead to more rapid regression of clinical symptoms of acute respiratory disease, more intensive strengthening neutrophils absorption capacity, metabolic and protease activity, activated by myeloperoxidase and cationic proteins. To improve of neutrophils phagocytic activity in patients with frequent acute respiratory diseases on the base of immunodeficiency disorders it could be recommended to increase the total dose of Licopid to 3 mg/daily and the frequency of repeated courses during the year, especially for patients of immunocompromised group.

[Induction and protective properties of antibodies against muramyl peptides of gram-negative bacteria]

AIM

Characterize the role of humoral immune response in mechanisms of action of muramyl dipeptide immune stimulators.

MATERIALS AND METHODS

Mice were immunized by a complex of muramyl peptides (CMP) obtained from Salmonella typhi peptidoglycan and consisting of 3 components: 1) N-acetyl-D-glucoasminyl-(beta1- > 4)-N-acetyl-D-muramoyl-L-alanyl-D-isoglutaminyl-meso-diaminopimelic acid (GMtri); 2) N-acetyl-D-glucosaminyl-(beta1- > 4)-N-acetyl-D-muramoyl-L-alanyl-D-isoglutaminyl-meso-diaminopimeloyl-D-alanine (GMtetra) and 3) GMtetra dimer (diGMtetra), in which monomeric residues of GMtetra are linked by an amid bond between carboxyl group of terminal D-alanine of one of GMtetra residues and omega-amino group of meso-diaminopimelic acid of the other GMtetra residue.

RESULTS

Immunization resulted in a multifold increase of IgM, IgG1 and IgG2a titers against CMP. Antibodies were directed against the whole molecule of diGMtetra and did not recognize its fragments. Sera of mice immunized with CMP protected the mice from lethal infection with Gram-negative (S. typhimurium) but not Gram-positive (Staphylococcus aureus) microorganisms.

CONCLUSION

Induction of protective antibodies may present a novel mechanism of action of muramyl dipeptide immune stimulators.

[Likopid in complex treatment of oral dysbiosis]

The aim of the study was to assess likopid effectiveness in complex treatment of oral dysbiosis. The study included 76 patients: 23 patients receiving antifungal and antimicrobial treatment, eubiotics and bacteriophages and 53 patients in which the above mentioned therapy was combined with licopid as immunocorrective agent. Laser flow cytometry was used to examine oral fluid bacteriostatic properties. The results of the study confirm licopid to be useful for complex treatment of oral dysbiosis.

[Use of the immunopotentiator N-acetyl-glucosamine-N-acetylmuramyl dipeptide during triple anti-Helicobacter pylori therapy]

AIM

To evaluate the efficiency of first-line Helicobacter pylori eradication therapy with glucosaminylmuramyldipeptide (Licopid JSC "Peptek", Russia).

SUBJECTS AND METHODS

Eradication therapy was performed in 128 patients (84 men and 34 women; mean age 44.1 +/- 13.5 years) with duodenal bulb ulcer associated with H. pylori. The latter was detected in the gastroduodenal mucosa by a morphological study and rapid urease test before and 6-8 weeks after treatment and discontinuation of all drugs. Gastric metaplasia areas in the duodenum were revealed by periodic acid-Schiff and Alcian blue staining. The patients were divided into 4 groups according to the treatment protocol: 1) omeprazole (O) 0.04 g/day, clarithromycin (C) 1 g/day, amoxicillin (A) 2 g/day for 7 days (OCA7; n = 33); 2) the above drugs for 14 days (OCA14; n = 34); 3) O 0.04 g/day, C 1 g/day, A 2.0 g/day for 7 days, and glucosaminylmuramyldipeptide (Licopid) (L) 0.001 g/day for a day (OCA7L1; n = 34) and 4) the above drugs and L 0.01 g/day for 10 (OCA7L10; n = 27).

RESULTS

According to the data of intention-to-treat analysis and per protocol, the H. pylori eradication rate was 81.8 and 87.1% for OCA7; 82.4 and 93.3% for OCA14; 88.2 and 93.8% for OCA7L1; 88.9 and 96% for OCA7L10 after PT and RRT, respectively. The rate of side effects was as follows: 6.1% for OCA7; 17.6% for OCA14 (5.9% stopped treatment); 5.9% for OCA7L1; 7.4% for OCA7L10. The cost of the treatment protocols was $ 32 for OCA7; $ 64 for OCA14; $ 40 for OCA7L1; $ 67 for OCA7L10. The intake of glucosaminylmuramyldipeptide (licopid) 0.001 g/day during 7-day triple anti-Helicobacter pylori therapy increased eradication by 6.4% (ITT) and 6.7% (PP), without raising the rate of side effects.

CONCLUSION

H. pylori-positive patients with duodenal bulb ulcer should be given glucosaminylmuramyldipeptide (Licopid) 0.001 g/day during 7-day first-line eradication therapy as alternative to the 14-day treatment regimen.

[Effects of immunocorrective therapy on immunological indices in patients with chronic bacterial prostatitis]

A total of 57 patients with chronic bacterial prostatitis were divided into two groups. The control group (n = 28) received standard treatment, the study group (n = 29) received treatment including immunomodulator likopid. The tests for IgA, IgM, IgG, compliment components C3, C4, circulating immune complexes were made, immunophenotyping of peripheral blood lymphocytes was performed, chemiluminescence parameters of whole blood and plasma, content of IL-10, TNF-alpha, IL-lbeta in seminal fluid were assessed. The detected abnormalities in parameters of systemic and mucose-associated immunity give ground for inclusion of immunomodulators in combined treatment of patients with chronic bacterial prostatitis.

[Correction of the immune disorders in patients with diabetes mellitus type II with complicated diabetic foot syndrome]

There were examined 86 patients, suffering mixed form of diabetic foot syndrome. In all the patients diabetes mellitus type II was diagnosed, the disease duration have constituted (12.3 +/- 2.5) yrs at average. The immune status was estimated, using determination of the lymphocytes subpopulations with the help of the monoclonal antibodies towards antigens reaction by the flowcytometry method, as well as concentration of the main classes of immunoglobulins IgA, IgM, IgG. The investigation was performed in dynamics: immediately after a patient admittance to hospital, on the 7 - 8th, 12 - 16th and 25 - 30th day. Basing on the analysis of the data obtained, there was conclusion made, that immediately after admittance to the hospital in the patients, suffering complicated diabetic foot syndrome, the disorders of cellular immunity of degree II and of humoral immunity of I degree were revealed. The indices improvement were noted while application of certain immunocorrecting therapy.

A synthetic NOD2 agonist, muramyl dipeptide (MDP)-Lys (L18) and IFN-β synergistically induce dendritic cell maturation with augmented IL-12 production and suppress melanoma growth

BACKGROUND

A synthetic NOD2 agonist, muramyl dipeptide (MDP)-Lys (L18), mimics the bacterial peptidoglycan moiety and acts as a powerful adjuvant that induces cell-mediated immunity.

OBJECTIVE

To investigate the induction of antitumor immune response for malignant melanoma by IFN-β in combination with MDP-Lys (L18) (IFN-MDP-Lys (L18)).

METHODS

Human monocyte-derived DCs (MoDCs) are stimulated with IFN-MDP-Lys (L18) in vitro. We assess the expression of costimulatory molecules on MoDCs by FACS. Moreover, we investigate the induction of Th1 cytokines by real time PCR and ELISA. Further to confirm the anti tumor immune response of IFN-MDP-Lys (L18) therapy, we examine the growth of B16F10 melanoma in vivo.

RESULTS

The stimulation of human MoDCs with IFN-MDP-Lys (L18) significantly augmented the production of IL-12p70, TNF-α, and IL-6 compared to that with MDP or that with IFN-β alone. IFN-MDP-Lys (L18) increased the expression of IL-12p35, IL-12p40, IL-10, TNF-α, IL-6 and IL-1β mRNA by MoDC using real-time PCR. The expression of CD83 and costimulatory molecules CD40, CD80, and CD86 was also augmented in MoDC treated with IFN-MDP-Lys (L18), which resulted in their augmented allogeneic T cell stimulation. In vivo, the administration of IFN-MDP-Lys (L18) significantly suppressed the growth of B16F10 melanoma, while the monotherapy of IFN-β or MDP-Lys (L18) did not significantly affect the tumor growth.

CONCLUSION

These findings suggest that IFN-MDP-Lys (L18) can be a promising adjuvant therapy for malignant melanoma.

Mifamurtide: osteosarcoma: ineffective and harmful

The standard treatment for children and young adults with osteosarcoma consists of surgery, preceded and followed by methotrexate-based chemotherapy. Mifamurtide is an immunostimulant derived from a bacterial cell wall component. It is authorised in the European Union as an adjunct to combination chemotherapy after complete excision of non-metastatic osteosarcoma. Only one comparative, unblinded trial has been published, and its design was particularly complex. In a study population of 678 patients, adding mifamurtide to chemotherapy after tumour excision did not prolong the overall 6-year survival rate, which was about 75% with both treatments. Only serious adverse effects were collected, and they were not systematically recorded. Hypersensitivity reactions occurred in clinical trials, along with pleural and pericardial effusions, seizures, and muscle spasms. Severe hearing loss occurred in 12% of the patients treated with mifamurtide in the comparative trial, versus 7% of the other patients. In practice, given the lack of any survival benefit and the risk of serious adverse effects, it is better not to add mifamurtide to chemotherapy regimens used for treatment of osteosarcoma.

[Evaluation of the efficiency and reactogenicity of emulsion-based adjuvant systems in the manufacture of polyclonal enteroviral diagnostic sera]

Whether various adjuvants might be used in the manufacture of commercial enteroviral diagnostic sera (EDS) was studied. The following adjuvants: Ribi, SAF-1, and TiterMax were compared; vaseline-lanoline emulsion used to prepare EDSs, as well as modified Freund's complete adjuvant served as controls. Chinchilla rabbits were intramuscularly injected enterovirus antigens (enterovirus 70 and ECHO 2) together with the adjuvant emulsions. TiterMax showed the highest efficiency comparable with the activity of Freund's adjuvant. The activities of Ribi, SAF-1, and vaseline-lanoline emulsion were 3-4 times lower. The neutralizing activity of the sera obtained after 2-3 (TiterMax) or 4-5 (Ribi, SAF-1) immunizations was maximal. Further immunizations resulted in a reduction in the titers of neutralizing antibodies. TiterMax and vaseline-lanoline emulsion caused minimal complications at the site of inoculation whereas SAF-1 and Ribi gave rise to severer inflammatory responses.

[Methodic approaches to treatment of the chronic generalized parodontitis in elderly and senile patients]

A comprehensive treatment with Likopid of chronic generalized parodontitis in 114 elderly and senile patients was carried out. The state of mechanisms of innate immunity (phagocytosis mechanisms) as well as the profile of proinflammatory cytokines was assessed. The effect of antibiotic-resistant strains of prior microflora on the combined therapy of patients of different age with chronic generalized parodontitis was studied. It is established that due to presence of various types of opportunistic pathogens in patients of different age with parodontitis using the prophylactic antibiotics for the empirical (to determine the antibiotic resistance), a combination of Metronidazole and Lincomycin with the mandatory appointment of immunomodulatory drugs for activation of monocyte-phagocytic system of the patient elderly is most advisable. Use of the drug , "Likopid" significantly improves the results of treatment the elderly and old patients with chronic generalized parodonthitis.

[Experience with use of immunomodulators in treatment of tonsillitis developed at the background of preimmunization by TEOVac]

The use of immunomodulators in the treatment of subjects with postvaccinal reactions to TEOVac was investigated. The most effective schemes were shown to be those with the use of viferon or combination of arbidol and licopide. The terms of the response signs cupping off were much shorter vs. the cases treated with polyoxidonium. The immunomodulating factors did not affect the intensity of the immunity to the vaccine virus.

Effect of cycloalkyl glycosides of muramyl dipeptide on antibacterial resistance of mice and cytokine production by human mononuclear cells

Beta-cyclohexylmethyl-, beta-cyclohexylethyl-, and beta-4-tert-butyl-cyclohexyl glycosides of muramyl dipeptide were shown to increase the resistance of mice to intraperitoneal infection with cultures of Staphylococcus aureus and Escherichia coli. These compounds increased the production of cytokines by mononuclear cells from healthy donors. Beta-cyclohexylethyl glycoside of muramyl dipeptide was more potent than muramyl dipeptide and other derivatives in increasing in vivo antibacterial resistance and in vitro production of interleukin-1beta, interleukin-6, tumor necrosis factor-alpha, and interferon-gamma;. This glycopeptide had a strong stimulatory effect on the production of interleukin-4 and tended to stimulate the synthesis of interferon-alpha. Beta-cyclohexylmethyl glycoside of muramyl dipeptide was most potent in stimulating the production of interleukin-4. Biological activity of beta-4-tert-butyl-cyclohexyl glycoside of muramyl dipeptide was lower than that of other glycosides of muramyl dipeptide.

[Influence of liposomal glucosaminyl-muramyl dipeptide on superoxide and nitric oxide production by murine macrophages]

Reactive oxygen and nitrogen intermediates are key factors in inflammatory response and antitumoral activity of macrophages. Free and liposomal N-acetylglucosaminyl-N-acetylmuramyl-L-alanyl-D-isoglutamine influence on murine macrophages ability to generate superoxide and nitric oxide were studied. The cells pretreated by GMDP increased superoxide generation in response to secondary stimuli (phorbol ether, lipopolysaccharide, zymosan). Encapsulation in the egg phosphatidylcholine liposomes enhanced cell sensitivity to priming effect of GMDP. The presence of liposomes (up to 0.5 mg/ml) in the medium inhibited superoxide release by macrophages probably due to participation of NO as redox-active metabolite. GMDP (up to 50 microg/ml) alone as well as GMDP with LPS treatment stimulated nitric oxide synthesis by macrophages. Liposomal GMDP at lower concentrations (up to 0.02 microg/ml) enhanced macrophage response to LPS. In contrast, NO-synthetic activity of LPS-stimulated cells decreased along with the increase of liposomal GMDP concentration (up to 0.5 microg/ml). The conditions for effective use of liposomal GMDP in immunotherapy are discussed.

Synthesis of N-acetyl-muramyl-L-alanyl-D-glutamic-alpha-amide(MDP) or -alpha-methyl ester derivatives, bearing a lipophilic group at the C-terminal peptide end

We report the synthesis of nine lipophilic derivatives of N-acetyl-muramyl-L-alanyl-D-glutamic-alpha-amide (MDP) or -alpha-methyl ester in which the gamma-carboxyl function of the D-glutamyl residue is either esterified by a medium chain alcohol or substituted by an L-alanyl residue esterified by a medium or long chain alcohol. A new method is described which easily allows one to obtain derivatives of MDP, bearing a free or substituted amino-acyl or peptidyl residue on the gamma-carboxyl function.

[Complex treatment of acute hematogenous osteomyelitis in children]

The acute hematogenous osteomyelitis continues to remain at present one of the actual problems to pediatric surgery, being characterized by severe course, difficulty of the early diagnostics and frequency of unfavourable outcomes, becoming chronic and complications. We investigated the levels of CRP, IL-1beta, TNF-alpha in 74 children with acute hematogenous osteomyelitis. In the first (control) group children had standart therapy, in the second (main) group children had standart therapy with Licopid. The level of TNF-alpha in the main group on 7 days after operation was 91,8 + or - 4,1 pcg/ml, on 14 days -- 44,3 + or - 8,3 pcg/ml. The level of TNF-alpha in the control group on 14 days was 92,0 + or - 2,0 pcg/ml (p<0,01). The level of IL-1beta in the main group on 7 days -- 120,0 + or - 30,8 pcg/ml, on 14 days -- 80,0 + or - 15,3 pcg/ml. The level of IL-1beta in the control group on 14 days -- 100,5 + or - 2,4 pcg/ml. The level of CRP in the main group on 14 days -- 22,9 + or - 4,1 mg/ml. The level of CRP in the control group on 14 days -- 12,9 + or - 0,4 mg/ml (p<0,05). The use the complex treatment of acute hematogenous osteomyelitis in children has allowed to obtain a good results of the treatment.

[Adverse immunologic effects of immunomodulators revealed in experiment and ways to their surmounting]

Immunomodulators licopid (synthetic analogue of muramylpeptide) and purified staphylococcal toxoid (PST) in some variants of experiments on mice caused adverse immunologic effects: enhancement of virus-induced immunosupression, shift from latent immunosupression (revealed only by low, but not standard, doses of test-antigen) to manifested one. Described adverse effects are not a contraindication for use of the studied drugs in practice. Their adverse effects were revealed only after single inoculation, whereas in clinical conditions PST and licopid are used by courses with duration of 5-7 and 10 days respectively. Our experiments show that inoculation of suppressive doses of the preparations repeated by 2-4 times can prevent the shift from latent to manifested immunosupression. Enhancement of immunosupression was not observed in case of combined administration of suppressive doses of PST and adjuvant dose of licopid.

Mifamurtide: CGP 19835, CGP 19835A, L-MTP-PE, liposomal MTP-PE, MLV 19835A, MTP-PE, muramyltripeptide phosphatidylethanolamine

Mifamurtide is a conjugate of muramyl tripeptide linked to dipalmitoyl phosphatidyl ethanolamine; the phospholipid facilitates incorporation of the peptide into liposomes. The agent stimulates macrophages to seek out and destroy cancer cells. The compound was originated by Novartis (formerly CIBA-Geigy), and is being developed by IDM Pharma for osteosarcoma. Mifamurtide is being reviewed by regulatory authorities in the US and EU for this indication.CIBA-Geigy originally developed mifamurtide in the early 1980s and the agent was subsequently outlicensed to Jenner Biotherapies in the 1990s. IDM Pharma acquired the rights to the drug from Jenner in April 2003.IDM and Genesis Pharma have entered into an exclusive licensing and marketing agreement for mifamurtide in South East Europe. Under the agreement terms, IDM will receive an upfront fee from Genesis, as well as milestone payments on reaching certain sales levels in the territory. Medison Pharma signed an agreement with IDM Pharma for the sales and marketing of mifamurtide in Israel. IDM will receive an upfront license fee from Medison and will be entitled to receive a milestone payment upon regulatory approval of the agent in Israel, as well as royalties on net sales.IDM outlicensed exclusive marketing rights for mifamurtide in the UK and Ireland to Cambridge Laboratories in June 2005. In exchange, IDM is entitled to an upfront license fee and milestone payments prior to launch, as well as royalties calculated on product sales.Previously, Chiron Vaccines (a joint venture between Novartis and Chiron formed in 1995) investigated mifamurtide as an adjuvant in HIV gp120 vaccine; however, development has been discontinued.IDM Pharma will purchase approximately 7.1 million shares of its common stock to raise approximately $US23.5 million in net proceeds. The company intends to use the funds for working capital and corporate purposes, including the company's activities related to gaining marketing approval of mifamurtide in the US and Europe. Following the announcement by ODAC in May 2007, IDM Pharma decided to amend the NDA for mifamurtide with additional vital status data from the completed phase III trial. This data was not available at the time the original filing was made, and the company believes that capturing this supplemental data will overcome the need for additional trials, further confirm the overall survival benefit of mifamurtide in osteosarcoma, and provide evidence for approvability. IDM Pharma intends to analyse the additional follow-up data and submit an amendment to the agency by the first quarter of 2008; the company is also working on addressing other concerns raised by the US FDA in the non-approvable letter. The US regulatory submission included safety and efficacy data from NCI-funded phase III trials in 678 patients with osteosarcoma conducted by the Pediatric Oncology Group and the Children's Cancer Group in over 147 US centres. The NDA also included safety and biological effects data of mifamurtide from 17 phase I and II studies in 248 patients conducted by Ciba-Geigy. In the EU, IDM Pharma filed a MAA with the EMEA in November 2006 for approval of mifamurtide (Mepacttrade mark) in combination with postoperative chemotherapy for the treatment of patients with newly diagnosed osteosarcoma following complete surgical resection. The company expects that the EMEA will make a decision regarding marketing approval for mifamurtide by the end of 2007. Mifamurtide has orphan drug status for the treatment of osteosarcoma in the US and EU.

[Synthesis and biological activity of aryl S-beta-glycosides of 1-thio-N-acetylmuramyl-L-alanyl-D-isoglutamine]

Phenyl, p-tolyl, and p-tert-butylphenyl beta-1-thio-N-acetylglucosaminides were synthesized by the treatment of thiophenols with peracetate of alpha-D-glucosaminyl chloride in the presence of triethylamine or under the conditions of phase-transfer catalysis with quaternary ammonium salts. The compounds synthesized were used for obtaining of glycosides of 4,6-O-isopropylidene-N-acetylmuramic acid, which were coupled with L-Ala-D-Glu(NH2)-OBzl and then deprotected to obtain the target aryl beta-thioglycosides of N-acetylmuramyl-L-alanyl-D-isoglutamine (MDP). The aryl beta-thioglycosides of MDP were found to stimulate an antibacterial resistance toward Staphylococcus aureus in mice. The reliable induction of the spontaneous activity of natural killers in the population of blood mononuclear cells was observed only for phenyl beta-thio-MDP at a dose of 200 microg/ml. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2008, vol. 34, no. 2; see also http://www.maik.ru.

[Dialkylmethyl beta-glycosides of N-acetylmuramyl-L-alanyl-D-isoglutamine: synthesis and infection protective and cytotoxic activities]

Symmetric secondary linear alcohols were proposed as aglycones for the synthesis of lipophilic beta-glycosides of N-acetylmuramyl-L-alanyl-D-isoglutamine (MDP). Pentadecan-8-ol, nonadecan-10-ol, and tricosan-12-ol were glycosylated by the oxazoline method. Based on the corresponding glucosaminides, alkyl beta-glycosides of 4,6-O-isopropylidene-N-acetylmuramic acid were synthesized and coupled with the dipeptide. Deprotection of isopropylidene groups by acidic hydrolysis and catalytic hydrogenolysis of benzyl esters resulted in the target muramyldipeptide glycosides. Nonadecan-10-yl and tricosan-12-yl [beta]-MDPs at doses 2 microg/mice most effectively stimulated antibacterial resistance in mice against Staphylococcus aureus. In contrast to the previously synthesized undecan-6-yl beta-MDP, pentadecan-8-yl, nonadecan-10-yl, and tricosan-12-yl beta-MDPs demonstrated direct cytotoxicity toward tumor cells E-562 and blood mononuclear cells.

Liposomal delivery of Mycobacterium leprae antigen(s) with murabutide and Trat peptide inhibits Fas-mediated apoptosis of peripheral blood mononuclear cells derived from leprosy patients

Protective immunity against intracellular pathogen Mycobacterium leprae is dependent on the activation of T cells. Repeated stimulation of T cells by M. leprae antigens MLCwA (M. leprae total cell wall antigen) and ManLAM (mannose capped lipoarabinomannan) may lead to apoptosis in leprosy patients. In the present study, inhibition of the Fas-induced apoptosis of peripheral blood mononuclear cells of leprosy patients was investigated using above M. leprae antigen(s), in combination with immunomodulators murabutide (MB) and a Trat peptide in particulate form (liposome). Incubation of the cells with particulate mode of antigen presentation led to both decreased percentage of propidium iodide (PI) positive cells and T cells expressing Fas-FasL, as well as decreased caspase-8/-3 activities in the lepromatous patients, thereby inhibiting apoptosis, while converse was true with stimulation with soluble antigen. Concurrently, there was an upregulation of antiapoptotic protein Bcl-X(L) in the lepromatous patients, thereby inhibiting apoptosis. Thus, the liposomal formulation of antigen promoted proliferation of anergized T cell by inhibiting apoptosis through decreased expression of death receptors and caspase activities and increased expression of anti-apoptotic protein Bcl-X(L) in these patients.

hPepT1 selectively transports muramyl dipeptide but not Nod1-activating muramyl peptides

Muramyl peptides derived from bacterial peptidoglycan are detected intracellularly by Nod1 and Nod2, 2 members of the newly characterized nod-like receptor (NLR) family of pattern recognition molecules. In the absence of bacterial invasion into the host cytosolic compartment, it remains unclear whether muramyl peptides can cross the plasma membrane and localize into the cytosol. We have recently demonstrated that the plasma membrane transporter, hPepT1, was able to efficiently translocate muramyl dipeptide (MDP), a specific Nod2-activating molecule, into host cells. We aimed to characterize the transport properties of hPepT1 towards a spectrum of muramyl peptides, including Nod1-activating molecules. To do so, we designed an original procedure based on the ectopic expression of hPepT1 in oocytes from Xenopus laevis. Our results demonstrated that hPepT1 transports MDP but no other Nod2-activating molecule. Moreover, we observed that Nod1-stimulating muramyl peptides were not transported by hPepT1. Since hPepT1 expression is strongly associated with intestinal epithelial cells, where Nod1 and Nod2 have been shown to play a key role, these observations suggest a distinct contribution of Nod1 and Nod2 in mucosal homeostasis following the cellular uptake of muramyl peptides by hPepT1.

Identification of pentadecapeptide mimicking muramyl peptide

We used monoclonal antibody, generated against N-acetylglucosaminyl-beta1-4-N-acetylmuramyl-alanyl-D-isoglutamine (GMDP), and phage display libraries of random peptides to select for oligopeptides, that mimic GMDP in their biological activity. Selected phage clones displayed a peptide RVPPRYHAKISPMVN (called RN-peptide) on their surface. This peptide was synthesized. RN-peptide was shown to augment the antibody response to ovalbumin in mice while the peptide was non-immunogenic and non-pyrogenic. We also characterized adjuvant activity of 14-, 10- and 7-mer analogs of RN-peptide truncated at the C-terminus and found them to be active. Because both carbohydrate and peptide fragments are critical for the biological activity of muramyl peptides, the results indicate that RN-peptide mimicks the spatial structure of intact GMDP.

Selective NOD1 agonists cause shock and organ injury/dysfunction in vivo

RATIONALE

NLRs (nucleotide oligomerisation domain [NOD] proteins containing a leucine-rich repeat) are cytosolic pattern recognition receptors. NOD1 senses diaminopimelic acid-containing peptidoglycan present in gram-negative bacteria, whereas NOD2 senses the muramyl dipeptide (MDP) present in most organisms. Bacteria are the most common cause of septic shock, which is characterized clinically by hypotension resistant to vasopressor agents. In animal models, gram-negative septic shock is mimicked by lipopolysaccharide (LPS), which signals through Toll-like receptor 4 (TLR4) and its adaptor MyD88. The role of NLRs in the pathophysiology of septic shock is not known.

OBJECTIVES

To compare the effects of selective NOD1 agonists with LPS in vivo.

METHODS

Vascular smooth muscle cells or whole aortas from wild-type or genetically modified mice were stimulated in vitro with agonists of NOD1 (FK565) or NOD2 (MDP). Vasoconstriction was measured using wire myography. Nitric oxide (NO) formation was measured using Griess reaction and NO synthase-II protein by Western blotting. In vivo, blood pressure, heart rate, and urine output were measured in sham-, LPS-, or FK565-treated animals. Biomarkers of end-organ injury, coagulation activation, NO, and cytokines were measured in plasma.

MAIN RESULTS

FK565, but not MDP, induced NO synthase-II protein/activity in vascular smooth muscle and vascular hyporeactivity to pressor agents. FK565 had no effect on vessels from NOD1(-/-) mice, but was active in vessels from TLR4(-/-), TLR2(-/-), or MyD88(-/-) mice. FK565 induced hypotension, increased heart rate, and caused multiple (renal, liver) injury and dysfunction in vivo.

CONCLUSIONS

Activation of NOD1 induces shock and multiple organ injury/dysfunction.

[Clinical laboratory substantiation of immunocorrection use in comprehensive treatment of chronic catarrhal gingivitis]

The role of immune system in development of chronic catarrhal gingivitis in 60 primary patients was defined and substantition of immunocorrection with Licopid in combined treatment was done.

[Immunomodulators of microbial origin enhance cytotoxicity of human mononuclear leukocytes and reduce metastatic progression of Lewis lung carcinoma in mice]

Effect of immunomodulators for microbial origin on innate immunity and antitumor system was continued to study. Immunomodificator Immunovac VP-4, purified staphylococcal toxoid and glucosaminyl muramyl dipeptide (GMDP) equally enhanced cytotoxicity of mononuclear leukocytes of peripheral blood of healthy donors. Index of cytotoxicity was 2.78, 2.77 and 2.70 respectively. Reduced metastatic progression of Lewis lung carcinoma in mice was observed after Immunovac VP-4 and GMDP administration. Effectiveness was seen when preparations administered according to schedules including their administration before implantation of the tumor. If preparations were administered number of metastases reduced in 4.4-5.6 times and size of metastases reduced in 7-10 times. Interplay between antitumor activity of studied immunomodulators and cytotoxic activity of NK-cells, which are base effectors of antitumor immune response, are discussed.

Comparative study of macrophage response in mice after DNA immunization and infection with herpes simplex virus type 1

Functional activity of macrophages and intensity of T cell immune response in mice were studied after intravaginal and intraperitoneal infection with herpes simplex virus type 1 and DNA vaccination in combination with adjuvant treatment (recombinant granulocyte-macrophage colony-stimulating factor and glucosaminylmuramyl dipeptide). DNA vaccination induced a virus-specific T cell immune response with no macrophagic inflammatory reaction. Infection with herpes simplex virus type 1 was accompanied by sustained inflammation, but not by the T cell immune response.

[Synthesis and protective anti-infective action of anomeric lipophilic glycosides of N-acetylmuramyl-L-alanyl-D-isoglutamine]

Anomeric pairs of alpha- and beta-dodecyl, alpha- and beta-(1-pentylhexyl), and alpha- and beta-cyclododecyl glycosides of N-acetylmuramyl-L-alanyl-D-isoglutamine (MDP) were synthesized. The starting beta-D-glucosaminides were obtained by the oxazoline method, and the corresponding alpha-isomers, by the mercuric iodide-catalyzed glycosylation of alcohols with alpha-glucosaminyl chloride peracetate in nitromethane at -90 degrees C. No reliable differences between the stimulation of mouse resistance to the infection with Staphylococcus aureus (doses of 2, 20, and 200 microg/mouse) and Escherichia coli (doses of 0.05, 1, and 20 microg/mouse) with the MDP alpha- and beta-glycosides were found.

Liposomal muramyl tripeptide phosphatidyl ethanolamine: ifosfamide-containing chemotherapy in osteosarcoma

Liposomal muramyl tripeptide phosphatidyl ethanolamine (L-MTP-PE) is a synthetic biological investigational agent used for treating osteosarcoma. It has been used in both canine and human osteosarcoma to reduce pulmonary metastases, the most common pattern of treatment failure for sarcomas. L-MTP-PE has been well tolerated using the concept of biological cancer therapy during chemotherapy. The use of L-MTP-PE with ifosfamide is the best studied combination with single agent chemotherapy. This may represent a new treatment choice for osteosarcoma patients receiving ifosfamide. Such patients include those with a poor initial histological response to primary therapy and/or metastatic disease including pulmonary metastases. Reduction of side effects of L-MTP-PE, such as fever and/or flu-like symptoms, with ibuprofen has not reduced efficacy. Since improved symptom control is possible using drug combinations that are especially effective for delayed nausea, outpatient high-dose ifosfamide chemotherapy combined with L-MTP-PE may lead to a safe and effective therapy while maintaining the patients’ quality of life.

Normal responses to specific NOD1-activating peptidoglycan agonists in the presence of the NOD2 frameshift and other mutations in Crohn's disease

Both NOD2/CARD15 alleles are mutated in approximately 10% of Crohn's disease patients, causing loss of functional responses to low-dose muropeptide agonists. We hypothesized that NOD2 mutations may also impair NOD1/CARD4 responses, supported by data suggesting NOD2 1007fs/1007fs patients had reduced responses to a putative NOD1 agonist, diaminopimelic acid-containing muramyl tripeptide (M-TriDAP). We measured peripheral blood mononuclear cell (n = 8 NOD2 wild type, n = 4 1007fs/1007fs, n = 6 702Trp/1007fs, n = 5 702Trp/702Trp, n = 3 908Arg/1007fs) responses to NOD1 agonists alone (IL-8/TNF-alpha), and agonist enhancement of lipopolysaccharide (LPS) responses (IL-1beta). Significant responses were seen with M-TriDAP at 10 nM (as with NOD2 agonists), but only at > or =100 nM with FK565/TriDAP. M-TriDAP induced IL-8/TNF-alpha secretion, and enhancement of LPS IL-1beta responses was significantly reduced between NOD2 double mutation carriers versus healthy controls, whereas there was no difference with FK565 or TriDAP stimulation, or between 1007fs/1007fs cells and other genotypes. M-TriDAP contains both NOD1 (gamma-D-Glu-mesoDAP) and NOD2 (MurNAc-L-Ala-D-Glu) minimal structures whereas FK565/TriDAP contain only NOD1 activating structures. M-TriDAP has dual NOD1/NOD2 agonist activity in primary cells, possibly due to different intracellular peptidoglycan processing compared to the HEK293 cell system typically used for agonist specificity studies. Responses to specific NOD1 agonists are unaffected by NOD2 genotype, suggesting independent action of the NOD1 and NOD2 pathways.

MDP and other muropeptides--direct and synergistic effects on the immune system

Muropeptides are breakdown products of peptidoglycan (PGN) of Gram-negative and Gram-positive bacteria. They are released during bacterial growth and division, as part of the host response by lysozyme and amidases, or upon antibiotic treatment. After phagocytosis of bacteria or bacterial breakdown products by host immune cells, the muropeptides trigger intracellular signaling cascades, leading to altered gene expression and activation of the immune response. Numerous muropeptides and derivatives have been synthesized chemically to characterize their immunostimulatory effects and adjuvant activity. Muramyl dipeptide, a natural partial structure of PGN, is the minimal structure with adjuvant activity. This review discusses the structure and occurrence of muropeptides and gives a broad overview of their inflammatory and adjuvant activity and the possible involvement of receptors in these responses.

Liposomal preparations of muramyl glycopeptides as immunomodulators and adjuvants

The need for safe and structurally defined immunomodulators and adjuvants is increasing in connection with the recently observed marked increase in the prevalence of pathological conditions characterized by immunodeficiency. Important groups of such compounds are muramyl glycopeptides, analogs of muramyl dipeptide (MDP), glucosaminyl-muramyl dipeptide (GMDP), and desmuramylpeptides. We have designed and synthesized new types of analogs with changes in both the sugar and the peptide parts of the molecule that show a high immunostimulating and adjuvant activity and suppressed adverse side effects. The introduction of lipophilic residues has also improved their incorporation into liposomes, which represent a suitable drug carrier. The proliposome-liposome method is based on the conversion of the initial proliposome preparation into liposome dispersion by dilution with the aqueous phase. The description of a home-made stirred thermostated cell and its link-up with a liquid delivery system for a rapid and automated preparation of multilamellar liposomes at strictly controlled conditions (sterility, temperature, dilution rate and schedule) is presented. The cell has been designed for laboratory-scale preparation of liposomes (300-1000 mg of phospholipid per run) in a procedure taking less than 90 min. The method can be readily scaled up. Examples of adjuvant and immunostimulatory effect of liposomal preparation in mice model will be presented.

Liposomal Muramyl Tripeptide Phosphatidylethanolamine: Targeting and Activating Macrophages for Adjuvant Treatment of Osteosarcoma

About one third of osteosarcoma patients develop lung metastasis refractory to chemotherapy. Recent studies indicate that biological response modifiers activating the patient's immune system may help controlling minimal residual disease via pathways distinct from those used by cytotoxic drugs, and therefore prove effective against tumor resistance. Muramyl tripeptide phosphatidylethanolamine (MTP-PE) is a synthetic lipophilic glycopeptide capable of activating monocytes and macrophages to a tumoricidal state. When intercalated in multilamellar liposomes (L-MTP-PE) and injected intravenously, it targets lung, liver, and spleen macrophages. Therapeutic activity of L-MTP-PE was demonstrated in several preclinical models of experimental lung metastasis and in clinical trials in dogs with osteosarcoma. Although macrophage activation was shown to be directly involved in the in vivo anti-metastatic activity of this molecule, cytokine and chemokine secretion by activated macrophages could induce recruitment and stimulation of other immune cells, which may in turn indirectly contribute to the anti-tumor effect. L-MTP-PE has undergone clinical development in humans. In early trials, most side effects of L-MTP-PE were minimal. L-MTP-PE showed signs of efficacy in treatment of patients with recurrent osteosarcoma and the encouraging results from phase II studies led to a phase III trial conducted by the Children's Oncology Group in patients with newly diagnosed high-grade osteosarcoma. Patients were treated with or without L-MTP-PE in combination with multi-drug chemotherapy in adjuvant setting; significantly higher overall survival and disease-free survival were observed in the group receiving L-MTP-PE.

Synthesis and proinflammatory properties of muramyl tripeptides containing lysine and diaminopimelic acid moieties

The unusual amino acid diaminopimelic acid (DAP) was prepared by cross metathesis of appropriately protected vinyl glycine and allyl glycine derivatives. Catalytic hydrogenation of the cross-coupling product resulted in reduction of the double bond and the removal of protecting groups. The resulting compounds were appropriately protected for the polymer-supported and solution-phase synthesis of muramyl tripeptides 2 and 3, which differ in the amidation of the alpha-carboxylic acids of the isoglutamine and DAP moieties. Muramyl dipeptide (1, MDP), the DAP-containing muramyl tripeptide 3, and the lysine-containing muramyl tripeptides 4 and 5 induced TNF-alpha gene expression without TNF-alpha protein production in a human monocytic cell line. The observed block in translation could be removed by co-incubation with LPS, resulting in an apparent synergistic effect. Compound 2 did not induce TNF-alpha gene expression, neither did it exhibit a synergistic effect with LPS; this indicates that amidation of the alpha-carboxylic acids of the isoglutamine and DAP moieties results in a loss of biological activity. It is proposed that amidation of alpha-carboxylic acids is a strategy that may be used by pathogens to avoid detection by the innate immune system. Furthermore, the pattern recognition receptors Nod1 and Nod2 have been implicated in the possible induction of a synergistic effect of muropeptides with LPS.

Muramyl peptides augment cytotoxic effect of tumor necrosis factor-alpha in combination with cytotoxic drugs on tumor cells

We have demonstrated that biologically active muramyl peptides, in particular, glucosaminylmuramyl dipeptide (GMDP), augmented in vitro cytotoxic activity of tumor necrosis factor-alpha (TNF-alpha) against murine fibrosarcoma L929 cells. The introduction of GMDP resulted in cytotoxic effect characteristic for substantially higher dose of cytokine. Even more potent was the combination of GMDP, TNF-alpha and Actinomycin D (ActD). According to clonogenic and MTT assays 100% L929 cells could be killed in culture with low doses of TNF-alpha and ActD if GMDP was present. When cisplatin was substituted for ActD similar results were obtained. GMDP also enhanced cytotoxicity of TNF-alpha and cisplatin against human breast carcinoma MCF7 and histiocytic lymphoma U937 cells. Normal cells, namely human peripheral blood leucocytes and murine peritoneal macrophages, were resistant to selected doses of TNF-alpha/cisplatin/GMDP.

Synthesis of peptidoglycan fragments and evaluation of their biological activity

The peptidoglycan (PG) bacterial cell wall glycoconjugate has been well known as a strong immunopotentiator. Partial structures of PG were chemically synthesized for elucidation of precise biological activities. Effective construction of distinct repeating glycans of PG was accomplished by the coupling of a key disaccharide glucosaminyl-beta(1-4)-muramic acid unit. Stereoselective glycosylation of disaccharide units was achieved by neighboring group participation of the N-Troc (Troc = 2,2,2-trichloroethoxycarbonyl) group and appropriate reactivity of N-Troc-glucosaminyl trichloroacetimidate. By using an efficient synthetic strategy, mono-, di-, tetra- and octasaccharide fragments of PG were synthesized in high yields. The biological activity of synthetic fragments of PG was evaluated by induction of tumor necrosis factor-alpha (TNF-alpha) from human monocytes, and toll-like receptor 2 (TLR2) and Nod2 dependencies by using transfected HEK293 cells, respectively. Here we reveal that TLR2 was not stimulated by the series of synthetic PG partial structures, whereas Nod2 recognizes the partial structures containing the MDP moiety.

[Synthesis and protective activity of beta-glycosides of N-acetylmuramyl-L-alanyl-D-isoglutamine with alkylalicyclic and arylaliphatic aglycons]

The following glycosides of N-acetylmuramyl-L-alanyl-D-isoglutamine (MDP) were synthesized: beta-4-tert-butylcyclohexyl MDP, beta-2-(adamant-1-yl)ethyl MDP, beta-2,2-diphenylethyl MDP, and 3-2-(p-biphenyl)ethyl MDP. The starting peracetylated beta-N-acetylglucosaminides were prepared by the oxazoline method. They were converted into 4,6-O-isopropylidene-N-acetyl-D-muramic acids, which were coupled with L-Ala-D-Glu(NH2)OBn. The target glycopeptides were obtained after their deprotection. The stimulation of the antiinfection resistance of mice against Staphylococcus aureus by the MDP glycosides was studied. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2005, vol. 31, no. 6; see also http://www.maik.ru.

A novel immunostimulator, N-[alpha-O-benzyl-N-(acetylmuramyl)-L-alanyl-D-isoglutaminyl]-N6-trans-(m-nitrocinnamoyl)-L-lysine, and its adjuvancy on the hepatitis B surface antigen

N(2)-[alpha-O-benzyl-N-(acetylmuramyl)-L-alanyl-D-isoglutaminyl]-N(6)-trans-(m-nitrocinnamoyl)-L-lysine (muramyl dipeptide C, or MDP-C) has been synthesized as a novel, nonspecific immunomodulator. The present study shows that MDP-C induces strong cytolytic activity by macrophages on P388 leukemia cells and cytotoxic activity by cytotoxic T lymphocytes (CTLs) on P815 mastocytoma cells. Our results also indicate that MDP-C is an effective stimulator for production of interleukin-2 and interleukin-12 by murine bone marrow derived dendritic cells (BMDCs) and production of interferon-gamma by CTLs. Additionally, MDP-C increases the expression levels of several surface molecules, including CD11c, MHC class I, and intercellular adhesion molecule-1 in BMDCs. Moreover, MDP-C remarkably enhances the immune system's responsiveness to hepatitis B surface antigen (HBsAg) in hepatitis B virus transgenic mice for both antibody production and specific HBsAg T-cell responses ex vivo. Our results indicate that MDP-C is an apyrogenic, nonallergenic, and low-toxicity immunostimulator with great potential for diagnostic, immunotherapeutic, and prophylactic applications in diseases such as hepatitis B and cancers.