Effects and plasma proteomic analysis of GLP-1RA versus CPA/EE, in combination with metformin, on overweight PCOS women: a randomized controlled trial.

PURPOSE: Polycystic ovary syndrome (PCOS) is characterized by reproductive dysfunctions and metabolic disorders. This study aims to compare the therapeutic effectiveness of glucagon-like peptide-1 receptor agonist (GLP-1RA) + Metformin (Met) versus cyproterone acetate/ethinylestradiol (CPA/EE) + Met in overweight PCOS women and identify potential proteomic biomarkers of disease risk in women with PCOS. METHODS: In this prospective, open-label randomized controlled trial, we recruited 60 overweight PCOS women into two groups at a 1:1 ratio to receive CPA/EE (2 mg/day: 2 mg cyproterone acetate and 35-µg ethinylestradiol,) +Met (1500 mg/day) or GLP-1 RA (liraglutide, 1.2-1.8 mg/day) +Met (1500 mg/day) for 12 weeks. The clinical effectiveness and adverse effects were evaluated, followed by plasma proteomic analysis and verification of critical biomarkers by ELISA. RESULTS: Eighty(80%) patients completed the study. Both interventions improved menstrual cycle, polycystic ovaries, LH(luteinizing hormone) and HbA1c(hemoglobin A1c) levels after the 12-week treatment. GLP-1RA + Met was more effective than CPA/EE + Met in reducing body weight, BMI (Body Mass Index), and waist circumference, FBG(fasting blood glucose), AUCI(area under curve of insulin),TC (Total Cholesterol), IL-6(Interleukin-6) and improving insulin sensitivity, and ovulation in overweight women with PCOS, with acceptable short-term side effects. CPA/EE + Met was more effective in improving hyperandrogenemia, including T(total testosterone), LH, LH/FSH(Luteinizing hormone/follicle-stimulating hormone), SHBG(sex hormone-binding globulin) and FAI (free androgen index). By contract, GLP-1RA+Met group only improved LH. Plasma proteomic analysis revealed that the interventions altered proteins involved in reactive oxygen species detoxification (PRDX6, GSTO1, GSTP1, GSTM2), platelet degranulation (FN1), and the immune response (SERPINB9). CONCLUSIONS: Both CPA/EE+Met and GLP-1RA + Met treatment improved reproductive functions in overweight PCOS women. GLP-1RA + Met was more effective than CPA/EE + Met in reducing body weight, BMI, and waist, and improving metabolism, and ovulation in overweight women with PCOS, with acceptable short-term side effects. CPA/EE + Met was more effective in reducing hyperandrogenemia. The novel plasma biomarkers PRDX6, FN1, and SERPINB9, might be indicators and targets for PCOS treatment. TRIAL REGISTRATION CLINICALTIALS. GOV TRIAL NO: NCT03151005. Registered 12 May, 2017, https://clinicaltrials.gov/ct2/show/NCT03151005 .

GSTP1 c.313A > G mutation is an independent risk factor for neutropenia hematotoxicity induced by anthracycline-/paclitaxel-based chemotherapy in breast cancer patients.

BACKGROUND: The link between glutathione S-transferase P1 (GSTP1) c.313A > G polymorphism and chemotherapy-related adverse events remains controversial. The goal of this study was to assess how this variant affected the toxicity of anthracycline-/paclitaxel-based chemotherapy in patients with breast cancer. METHODS: This study retrospectively investigated pharmacogenetic associations of GSTP1 c.313A > G with chemotherapy-related adverse events in 142 breast cancer patients who received anthracycline and/or paclitaxel chemotherapy. RESULTS: There were 61 (43.0%), 81 (57.0%), 43 (30.3%), and 99 (69.7%) patients in the T0-T2, T3-T4, N0-N1, and N2-N3 stages, respectively. There were 108 (76.1%) patients in clinical stages I-III and 34 (23.9%) patients in clinical stage IV. The numbers of patients with luminal A, luminal B, HER2 + , and triple-negative breast cancer (TNBC) were 10 (7.0%), 77 (54.2%), 33 (23.2%), and 22 (15.5%), respectively. The numbers of patients who carried GSTP1 c.313A > G A/A, A/G, and G/G genotypes were 94 (66.2%), 45 (31.7%), and 3 (2.1%), respectively. There were no statistically significant differences in the proportion of certain toxicities in patients with A/G, G/G, and A/G + G/G genotypes, except for neutropenia, in which the proportion of patients with A/G + G/G (χ2 = 6.586, P = 0.035) genotypes was significantly higher than that with the AA genotype. The logistic regression analysis indicated that GSTP1 c.313A > G mutation (A/G + G/G vs. A/A genotype) (adjusted OR 4.273, 95% CI 1.141-16.000, P = 0.031) was an independent variable associated with neutropenia. CONCLUSIONS: The findings of this study indicate that the GSTP1 c.313A > G mutation is an independent risk factor for neutropenia hematotoxicity in breast cancer patients induced by anthracycline-/paclitaxel-based chemotherapy.

Contribution of the Gut Microbiota in P28GST-Mediated Anti-Inflammatory Effects: Experimental and Clinical Insights.

An original immuno-regulatory strategy against inflammatory bowel diseases based on the use of 28 kDa glutathione S-transferase (P28GST), a unique schistosome protein, was recently proposed. Improvement of intestinal inflammation occurs through restoration of the immunological balance between pro-inflammatory T-helper 1 (Th1) responses and both T-helper 2 (Th2) and regulatory responses. However, detailed mechanisms explaining how P28GST prevents colitis and promotes gut homeostasis remain unknown. Considering the complex interplay between the adaptive and innate immune system and the intestinal microbiota, we raised the question of the possible role of the microbial ecosystem in the anti-inflammatory effects mediated by the helminth-derived P28GST protein. We first analyzed, by 16S rRNA sequencing, the bacterial profiles of mice fecal microbiota at several time points of the P28GST-immunomodulation period prior to trinitrobenzene sulfonic acid (TNBS)-colitis. The influence of gut microbiota in the P28GST-mediated anti-inflammatory effects was then assessed by fecal microbiota transplantation experiments from P28GST-immunized mice to either conventional or microbiota depleted naïve recipient mice. Finally, the experimental data were supplemented by the temporal fecal microbiota compositions of P28GST-treated Crohn's disease patients from a pilot clinical study (NCT02281916). The P28GST administration slightly modulated the diversity and composition of mouse fecal microbiota while it significantly reduced experimental colitis in mice. Fecal microbiota transplantation experiments failed to restore the P28GST-induced anti-inflammatory effects. In Crohn's disease patients, P28GST also induced slight changes in their overall fecal bacterial composition. Collectively, these results provide key elements in both the anti-inflammatory mechanisms and the safe therapeutic use of immunomodulation with such promising helminth-derived molecules.

Peroxiredoxin 3 promotes IL-12 production from macrophages and partially protects mice against infection with Toxoplasma gondii.

Toxoplasmosis remains a life-threatening infection of humans and various domestic and wild animals worldwide. It is caused by the obligatory intracellular protozoan parasite Toxoplasma gondii. Peroxiredoxins (Prxs) are a family of antioxidant enzymes that protect cells from oxidative stress from hydroperoxides. In the recent years, several studies have reported the potential use of T. gondii-derived enzymes in triggering protective immunity against T. gondii infection. Therefore, this study was conducted to investigate the immunogenicity and protective efficacy of TgPrx3. In vitro stimulation of peritoneal macrophages with recombinant TgPrx3 protein fused to glutathione-S transferase (TgPrx3-GST) enhanced IL-12p40 production, indicating the immune-stimulating potentials of TgPrx3. Next, protective efficacy was investigated by subcutaneous inoculation of mice with TgPrx3-GST (25pmol), and recombinant GST or PBS were used as the controls. Mice immunized with TgPrx3-GST exhibited a significant elevation of specific antibodies in terms of IgG1 and IgG2c isotypes. Moreover, interferon-gamma production and spleen cell proliferation dramatically increased in the TgPrx3-GST-sensitized cells from mice immunized with the same antigen. The severity of the T. gondii infections tended to be attenuated in the TgPrx3-GST-immunized mice, as evidenced by their higher survival rates and lower parasite burdens in the brain. Altogether, TgPrx3 immunization induced specific humoral and cellular immune responses and partially protected the mice against lethal toxoplasmosis. Our results suggest the possible use of TgPrx3 as a vaccine candidate against T. gondii infections.

Clinical outcome of cisplatin-based chemotherapy is associated with the polymorphisms of GSTP1 and XRCC1 in advanced non-small cell lung cancer patients

Introduction. This study is to evaluate the association of polymorphisms of glutathione S-transferase P1 (GSTP1), copper-transporting P-type adenosine triphosphatase A (ATP7A) and X-ray repair cross-complementing group 1 (XRCC1) with the efficacy and toxicity of cisplatin-based treatment in advanced non-small cell lung cancer (NSCLC) patients. Materials and methods. The outcomes of 97 advanced non-small cell lung cancer patients treated with cisplatin-based chemotherapy were estimated. GSTP1, ATP7A, and XRCC1 genetic polymorphisms were determined via polymerase chain reaction of restriction fragment length polymorphism (PCR–RFLP) and DNA sequencing. Association of the polymorphisms with the efficacy and toxicity of cisplatin was analyzed, respectively. Results. Significant associations were observed between GSTP1 A313G and response rate (RR) (p = 0.027), disease control rate (DCR) (p = 0.019), and progression-free survival (PFS) (p = 0.044), respectively. Patients with AG and GG of GSTP1 have notably lower risk of anemia (p = 0.046). XRCC1 A1196G was associated with the incidence of lymphopenia (p = 0.024) and diarrhea (p = 0.020). ATP7A C2299G was not related with RR, DCR, PFS, and the risk of toxicity. Conclusions. Advanced NSCLC patients with AA genotype of GSTP1 would obtain better curative effect followed with more risk of anemia when treated by cisplatin-based chemotherapy. ATP7A C2299G does not impact the efficacy and toxicity of cisplatin-based chemotherapy. XRCC1 1196A allele could predict the incidence of lymphopenia and diarrhea (AU)

No disponible

Tumor targeting of a cell penetrating peptide by fusing with a pH-sensitive histidine-glutamate co-oligopeptide.

Cell penetrating peptides (CPPs) have been well established as potential carriers for intracellular delivery of protein/peptide therapeutics. However, their lack of selectivity impedes their application in vivo. In order to increase their specificity, a highly pH-sensitive histidine-glutamate (HE) co-oligopeptide was fused with a CPP, i.e. model amphipathic peptide (MAP), and was expressed as a fusion protein with glutathione S-transferase (GST) acting as a cargo protein. Compared with two other fusion proteins containing either HE or MAP, only the fused peptide (HE-MAP) could effectively deliver the cargo GST protein to cells at pH 6.5 or below, while maintaining low delivery to cells at pH 7.0 and above. Using a xenograft mouse model of human breast cancer, fluorescent imaging showed that only HE-MAP could effectively target GST to the tumor site, while reducing non-specific association of MAP in other organs. The data presented in this report demonstrate the diagnostic and/or therapeutic potential of the fused peptide, HE-MAP, for targeting the acidic tumor microenvironment. The concise design for this pH-sensitive peptide offers a simple way to overcome CPP's lack of selectivity, which could lead to increased application of CPPs and macromolecular therapeutics.

Nuevas estrategias en terapia antitumoral basadas en la inducción de la apoptosis / New strategies in antitumor therapies based on apoptosis induction

Según la OMS para el año 2030 se producirán un total de 11,5 millones de defunciones por cáncer. Una alta proporción de estos tumores serán resistentes a los agentes antineoplásicos actuales, por ello, en los últimos años se ha realizado una intensa labor investigadora en la búsqueda de nuevas dianas para el tratamiento de tumores. Una de las dianas que está ofreciendo más posibilidades es el mecanismo de la apoptosis. La apoptosis se produce en condiciones fisiológicas como un mecanismo regulador del crecimiento de tejidos, en equilibrio con la proliferación celular. Su desregulación podría ayudar a explicar la patogénesis de algunos tumores malignos (AU)

According to OMS, in 2030 will be a total of 11.5 million deaths by cancer. A high proportion of these tumors will be resistant to current anticancer agents, and therefore, in the last years an intense investigation has been done to search new targets for antitumor treatment. One of the most interesting targets is the apoptosis mechanism. Apoptosis is produced in physiological conditions as a growth tissue regulator mechanism, in equilibrium with cellular proliferation. Its deregulation could explain the pathogenesis of some malignant tumors (AU)

A study on effects of glutathione s-transferase from silkworm on CCL4-induced mouse liver injury.

To assess the hepatoprotective activity of Glutathione S-transferase(GSTsw), extracted and purified from silkworm, in experimental acute mice liver injury and explore mechanisms. Mice were divided into five groups: control group, carbon tetrachloride (CCl4) group, and three treatment groups that received CCl4 and GSTsw at doses of 0.083 mg•g(-1), 0.0415 mg•g(-1) and 0.0207 mg•g(-1) for 3 days. ALT in serum, GST, SOD and T-AOC in liver tissue homogenate, and changes in liver pathology in the five groups were studied. CCl4 administration led to pathological and biochemical evidence of liver injury as compared to untreated controls. GSTsw administration led to significant protection against CCl4-induced changes in liver pathology. It was also associatedwith significantly lower serum ALT levels, higher GST-SOD and T-AOC level in live tissue homogenate. Thus, GSTsw showed protective activity against CCl4-induced hepatotoxicity in mice.

[Protective efficacy induced by dendritic cells pulsed with GST in combination with CpG oligodeoxynucleotide against Schistosoma japonicum infection].

OBJECTIVE: To study the protective effects on the infection of Schistosoma japonicum in C57BL/6 mice induced by dendritic cells DCs pulsed with GST in combination with CpG oligodeoxynucleotide. METHODS: GST was purified and used to stimulate DC2.4 cell line. Antigen loading was analyzed by immunofluorescence method. Thirty-five C57BL/6 mice were divided into seven groups(5 mice per group). Mice in groups A, B, C, D and E were immunized subcutaneously with DCs, DCs treated with PSA, DCs pulsed with GST, DCs stimulated with GST+CpG ODN, DCs stimulated with CpG ODN, respectively. For the above five groups, each mouse received 100 microl cell suspension at the density of 10(7)/ml subcutaneously for three times at 2-week intervals. Each mouse of group F was immunized subcutaneously with 50 microg GST formulated in complete Freund's adjuvant first, and 50 microg, 10 microg GST respectively in incomplete Freund's adjuvant for the last two doses. Group G received PBS and served as control. Serum samples were collected 10 days after the final immunization, and were analyzed for specific antibodies by ELISA. At two weeks after the final immunization, each mouse were challenged by 30 +/- 1 cercariae of S. japonicum. Six weeks after infection the mice were sacrificed, and number of worms was counted. RESULTS: Light green fluorescence was observed in dendritic cells under the fluoroscope after pulsing with GST which indicated the protein loaded dendritic cells. The IgG level in groups C, D and F was 0.555 2 +/- 0.078 9, 0.715 0 +/- 0.052 3, and 2.127 0 +/- 0.411 5, respectively, all higher than that of group G (P < 0.05). The worm reduction rate of group D was 53.3%, followed by group F (24.0%) and group C (21.3%). There was no significantly difference in the worm reduction rate between group D and groups F and C (P > 0.05). CONCLUSION: Dendritic cells pulsed with GST in combination with CpG oligodeoxynucleotide induce significant immunoprotection against the infection of Schistosoma japonicum.

Enzymes and bioscavengers for prophylaxis and treatment of organophosphate poisoning.

Organophosphorus (OP) pesticide poisoning causes significant morbidity and mortality, particularly in the developing world, with upwards of 3 million people poisoned each year. Although OP poisoning is not common in developed countries, recently greater attention has been given to these chemicals because of their similarity to chemical warfare agents. Despite the agricultural use of OP pesticides for roughly 60 years, no new therapies have been developed since the 1960s. A promising field of novel antidotes for OP poisoning, OP hydrolases, has recently garnered increased support. These bacterial enzymes have demonstrated tremendous prophylactic and antidotal efficacy against a few different OP classes in animal models. These studies, as well as the limitations and challenges of therapeutic development of these enzymes, are discussed.

Protective effect of glutathione S-transferase-fused mutant staphylococcal enterotoxin C against Staphylococcus aureus-induced bovine mastitis.

Recent studies have demonstrated that immunization with nontoxic mutant staphylococcal enterotoxin C (mSEC) provides protection against Staphylococcus aureus infection in mouse models. In the present study, we investigated whether vaccination with a glutathione S-transferase-fused SEC (GST-mSEC) can protect against S. aureus-induced bovine mastitis. Cows were immunized with the GST-mSEC plus alum adjuvant and then challenged with viable S. aureus by an intramammary route. The results showed that immunization with GST-mSEC-induced production of SEC-specific antibodies in sera and the high titers of antibodies could persist for over 12 weeks. Importantly, immunization with GST-mSEC also induced production of SEC-specific antibodies in milk. The somatic cell counts in the milk from S. aureus challenged quarters of vaccinated lactating cows were significantly lower than those of the non-vaccinated control animals. Furthermore, the sera from GST-mSEC-immunized cows significantly inhibited interferon-gamma and tumor necrosis factor-alpha production from mouse spleen cells induced by wild-type SEC. These results suggest that vaccination with GST-mSEC provides protection against S. aureus-induced bovine mastitis and that the protection might be mediated by SEC-neutralizing antibodies.

Identification of immunodominant Th1-type T cell epitopes from Schistosoma japonicum 28 kDa glutathione-S-transferase, a vaccine candidate.

Th1-type cytokines produced by the stimulation of Th1-type epitopes derived from defined schistosome-associated antigens are correlated with the development of resistance to the parasite infection. Schistosoma mansoni 28 kDa glutathione-S-transferase (Sm28GST), a major detoxification enzyme, has been recognized as a vaccine candidate and a phase II clinical trial has been carried out. Sheep immunized with recombinant Schistosoma japonicum 28GST (Sj28GST) have shown immune protection against the parasite infection. In the present study, six candidate peptides (P1, P2, P3, P4, P7 and P8) from Sj28GST were predicted, using software, to be T cell epitopes, and peptides P5 and P6 were designed by extending five amino acids at the N-terminal and C-terminal of P1, respectively. The peptide 190-211 aa in Sj28GST corresponding to the Th1-type epitope (190-211 aa) identified from Sm28GST was selected and named P9. The nine candidate peptides were synthesized or produced as the fusion protein with thioredoxin in the pET32c(+)/BL21(DE3) system. Their capacity to induce a Th1-type response in vitro was measured using lymphocyte proliferation, cytokine detection experiments and flow cytometry. The results showed that P6 (73-86 aa) generated the strongest stimulation effect on T cells among the nine candidate peptides, and drove the highest level of IFN-gamma and IL-2. Therefore, P6 is a functional Th1-type T cell epitope that is different from that in Sm28GST, and will be useful for the development of effective vaccines which can trigger acquired immunity against S. japonicum. Moreover, our strategy of identifying the Th1-type epitope by a combination of software prediction and experimental confirmation provides a convenient and cost-saving alternative approach to previous methods.

Fasciola antigens as vaccines against fascioliasis and schistosomiasis.

Fascioliasis is an important trematode infection of herbivores worldwide with increasing evidence of prevalence as a disease of humans. Vaccination studies with purified native and recombinant Fasciola antigens suggest that this approach to diminished morbidity and mortality and reduced transmission is a realistic goal. Among the major potential vaccine candidates are fatty acid binding protein (FABP), cysteine (cathepsin) proteases, haemoglobulin, leucine aminopeptidase, and a saposin-like protein. In the case of Fasciola hepatica FABP, cross-reaction and cross-protection against Schistosoma mansoni is an important feature. In addition to protective effects with significant worm burden reductions, some vaccine candidates also have anti-fecundity (smaller flukes), anti-pathology (less liver lesions), and anti-embryonation effects. Optimism is tempered by the fact that fascioliasis in humans is an orphan disease and in need of governmental and foundation support.

Sulfur in human nutrition and applications in medicine.

Because the role of elemental sulfur in human nutrition has not been studied extensively, it is the purpose of this article to emphasize the importance of this element in humans and discuss the therapeutic applications of sulfur compounds in medicine. Sulfur is the sixth most abundant macromineral in breast milk and the third most abundant mineral based on percentage of total body weight. The sulfur-containing amino acids (SAAs) are methionine, cysteine, cystine, homocysteine, homocystine, and taurine. Dietary SAA analysis and protein supplementation may be indicated for vegan athletes, children, or patients with HIV, because of an increased risk for SAA deficiency in these groups. Methylsulfonylmethane (MSM), a volatile component in the sulfur cycle, is another source of sulfur found in the human diet. Increases in serum sulfate may explain some of the therapeutic effects of MSM, DMSO, and glucosamine sulfate. Organic sulfur, as SAAs, can be used to increase synthesis of S-adenosylmethionine (SAMe), glutathione (GSH), taurine, and N-acetylcysteine (NAC). MSM may be effective for the treatment of allergy, pain syndromes, athletic injuries, and bladder disorders. Other sulfur compounds such as SAMe, dimethylsulfoxide (DMSO), taurine, glucosamine or chondroitin sulfate, and reduced glutathione may also have clinical applications in the treatment of a number of conditions such as depression, fibromyalgia, arthritis, interstitial cystitis, athletic injuries, congestive heart failure, diabetes, cancer, and AIDS. Dosages, mechanisms of action, and rationales for use are discussed. The low toxicological profiles of these sulfur compounds, combined with promising therapeutic effects, warrant continued human clinical trails.

Vaccine strategies against schistosomiasis: from concepts to clinical trials.

Schistosomiasis, the second major parasitic disease in the world after malaria, affects 200 million people. Vaccine strategies represent an essential component of the control of this chronic debilitating disease where the deposition of millions of eggs in the tissues is the main cause of pathology. Research developed in our laboratory over the last 20 years has led to the identification of novel effector mechanisms, pointing for the first time to the protective role of Th2 responses and of IgE antibodies now supported by seven studies in human populations. The identification and molecular cloning of a target antigen, a glutathione S-transferase (GST), has made it possible to demonstrate its vaccine potential in several animal species (rodents, cattle, primates) and to establish consistently the capacity of vaccination to reduce female worm fecundity and egg viability through the production of neutralizing antibodies (IgA and IgG). Following promising preclinical studies, clinical trials (phase I and II) have been undertaken using Schistosoma haematobium GST, Sh28GST. High titers of neutralizing antibodies were produced (IgG3 and IgA) together with Th2 cytokines, consistently with the concepts developed from experimental models. With these results we are on the way towards a feasible approach of vaccine development against a major human parasitic disease.

Anti-miracidial effect of recombinant glutathione S-transferase 26 and soluble egg antigen on immune responses in murine schistosomiasis mansoni.

The anti-miracidial potential of recombinant Schistosoma mansoni glutathione S-transferase 26 (rSmGST26) or native crude soluble egg antigens (SEA) was assessed. The associated dynamics of granuloma formation and immune responses were evaluated. Naive C57BL/6 mice were injected intravenously with multiple doses of either SEA (SEA-group) or rSmGST26 (GST-group) 7 days before cercarial infection. The immunized groups and the respective controls were sacrificed 6, 8 and 16 weeks postinfection (p.i.). Acceleration of ova destruction and reduction of granuloma diameter were greater in the GST-group than the SEA-group, mainly at 8 weeks p.i. However, the amelioration of hepatic pathology and function was more evident in the SEA-group. Concurrently, serum-specific IgG1 levels were elevated throughout the course of infection in the immunized groups compared to the infected controls. Initial rise of all splenic cytokines and serum anti-SEA IgE levels at 6 weeks p.i. was observed, followed by a dramatic drop in the levels of the proinflammatory cytokines IL-2, IFNgamma, IL-4 and TNF-alpha and IgE at 8 weeks of infection. IL-10 level was lower at 8 weeks p.i. than at 6 weeks, but was higher in immunized groups than in infected controls. Several responses may be implicated as an outcome of the present immunization protocol, such as increased levels of blocking antibody (IgG1) and IL-10 with decreased levels of proinflammatory cytokines and IgE.

Overexpression of human glutathione S-transferase pi protects NIH 3T3 cells against (+/-)anti BPDE cytotoxicity but not tumor formation.

In order to explore the protective function of human glutathione S-transferase pi (GST-pi) in vitro and in vivo, transfected NIH 3T3 clones were examined in cytotoxicity assays using the carcinogen (+/-)anti-benzo(a)pyrene 7,8-diol-9,10-epoxide (BPDE) or inoculated into nude mice and treated with the carcinogen benzo(a)pyrene (BP) to induce tumor formation. The human GST-pi cDNA under the control of the murine alpha 2(I)collagen promoter was transfected into NIH 3T3 cells and G418 resistant clones were analyzed by Southern, northern, western, and two-dimensional analysis. Clone A2 stably expressed human GST-pi and has 2.5-fold greater activity toward the substrate 1-chloro-2,4-dinitrobenzene and a 1.7-fold increase in LD50 for BPDE in vitro when compared to control-transfected clone G3. This increase in protection, however, did not prevent the formation of BP-induced tumors in vivo.

[Vaccine against bilharziasis. Strategies and perspectives]. / Un vaccin contre les bilharzioses. Stratégies et perspectives.

Due to the determination of immunity acquisition mechanisms, a number of studies on experimental models and human populations has made it possible to devise a strategy of vaccination against schistosomiasis, a major worldwide parasitic disease affecting 200 million people. A schistosomial protein, identified as glutathione-S-transferase (SM28GST) has been cloned and expressed in various vectors. Immunization with the recumbent protein results in a significant reduction of the parasitic load, while the fertility of schistosoma and the viability of its eggs are markedly inhibited. Recent experiments performed in primates and bovines have shown that a more than 90% inhibition of the schistosoma's transmission potential can be induced by this vaccine. The important role played by IgA antibodies in the inhibition of the parasite's fertility has led to the development of an oral immunization strategy. In view of the results obtained, the availability, in the near future, of a vaccine protecting human beings against this scourge can be considered realistic.

Antitoxic properties of a preparation of glutathione S-transferase.

Pretreatment of rats with a preparation of the cationic form of rat liver cytosolic glutathione S-transferase 1-3 h before injection of a dose of N-nitroso-N-diethylamine equivalent to the LD50 of the drug completely protects the animals against the toxic effects of the drug. The mechanism of the protective action of glutathione S-transferase is discussed.