ABSTRACT
The aim of the present study was to investigate the influence of a nonselective COX1/COX2 inhibitor (indomethacin) on tumor growth of Ehrlich Ascites Tumor (EAT) in mice, using as parameters the tumor growth and cytokine profile. Mice were inoculated with EAT cells and treated with indomethacin. After 1, 3, 6, 10, and 13 days the animals were evaluated for the secretion of TNFα, IL-1α, IL-2, IL-4, IL-6, IL-10, and IL-13 and PGE2 level in peritoneal cavity. The results have shown that EAT induces PGE2 production and increases tumor cells number from the 10th day. The cytokine profile showed EAT induces production of IL-6 from 10th day and of IL-2 on 13th day; the other studied cytokines were not affected in a significant way. The indomethacin treatment of EAT-bearing mice inhibited the tumor growth and PGE2 synthesis from the 10th day. In addition, the treatment of EAT-bearing mice with indomethacin has stimulated the IL-13 production and has significantly inhibited IL-6 in the 13th day of tumor growth. Taken together, the results have demonstrated that EAT growth is modulated by PGE2 and the inhibition of the tumor growth could be partly related to suppression of IL-6 and induction of IL-13.
Subject(s)
Carcinoma, Ehrlich Tumor/drug therapy , Carcinoma, Ehrlich Tumor/immunology , Animals , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Carcinoma, Ehrlich Tumor/metabolism , Cytokines/blood , Indomethacin/therapeutic use , Interleukin-10/blood , Interleukin-13/blood , Interleukin-2/blood , Interleukin-4/blood , Interleukin-6/blood , Male , MiceABSTRACT
OBJECTIVE AND DESIGN: The effects of anesthetics on cytokine release in patients without comorbidities who undergo minor surgery are not well defined. We compared inflammatory cytokine profiles in adult patients undergoing minimally invasive surgery who received isoflurane or propofol anesthesia. METHODS: Thirty-four patients without comorbidities undergoing minor surgery were randomly assigned to receive an inhaled anesthetic (isoflurane; n = 16) or an intravenous anesthetic (propofol; n = 18). Blood samples were drawn before premedication and anesthesia (T1), 120 min after anesthesia induction (T2), and on the first post-operative day (T3). Plasma concentrations of interleukins (IL-) 1ß, 6, 8, 10 and 12 and tumor necrosis factor (TNF)-α were measured using flow cytometry. RESULTS: The pro-inflammatory cytokine IL-6 was increased in the isoflurane group at T2 and T3 compared to T1 (P < 0.01). In the propofol group, IL-6 and IL-8 were significantly increased at T3 compared to T1. However, there were no significant differences in cytokine concentrations between the isoflurane and propofol groups. CONCLUSION: An inflammatory response occurred earlier in patients who received an inhaled agent compared with an intravenous anesthetic, but no differences in plasma cytokine profiles were evident between isoflurane and propofol anesthesia in patients without comorbidities undergoing minimally invasive surgeries.
Subject(s)
Anesthetics, Inhalation/pharmacology , Anesthetics, Intravenous/pharmacology , Cytokines/blood , Isoflurane/pharmacology , Propofol/pharmacology , Adolescent , Adult , Female , Humans , Male , Otorhinolaryngologic Surgical Procedures , Young AdultABSTRACT
Solanum paniculatum L. or popularly known as "jurubeba" is an herbal medicinal plant. A few studies have investigated its biological effects; however, research aimed at elucidating the redox balance effects from its fruits has not been reported so far. ROS interplays in various fields of medicine such as chemotherapy. Here, we evaluated antioxidant and inflammatory activities of the hydroethanolic extract of Solanum Paniculatum L. (HESPL) fruits in breast cancer cells, as well as its phytochemical profile. The antioxidant profile (carotenoids and phenolic compounds) was obtained by HPLC-DAD-UV and HPLC-APCI-MS. Cancer cell lines and human vein endothelial cells (HUVECs) were cultivated and treated with 1.87-30 µg/mL of HESPL for 24 hrs. Cytotoxicity, oxidative, and inflammation biomarkers were evaluated. The dose of 30 µg/mL of the HESPL extract presented cytotoxicity in the MCF-7 cell line. However, for MDA-MB-231, the cytotoxicity was observed in the dose of 1.87 g/mL. The 1.87 µg/mL and 3.75 µg/mL doses decreased the concentration of IL-6 in MCF-7 cells. In the MDA-MB-231 cells, the HESPL did not decrease the IL-6 concentration; however, in the doses of 15 and 30 µg/mL, an increase in this parameter was observed. The HESPL increased IL-1ß concentration in HUVECs. The ROS level in MCF-7 was elevated only at the 30 µg/ml dose. Regarding MDA-MB-231, HESPL promoted increased ROS levels at all doses tested. HUVEC showed no increase in ROS under any dose. HESPL treatment may modulate cytotoxicity, ROS, and cytokine levels due to its phytochemical profile, and it has shown an antioxidant or anti-inflammatory effect.
Subject(s)
Cytokines/metabolism , Ethanol/chemistry , Fruit/chemistry , Plant Extracts/pharmacology , Reactive Oxygen Species/metabolism , Solanum/chemistry , Water/chemistry , Carotenoids/analysis , Cell Line , Cell Survival/drug effects , HumansABSTRACT
γ-Oryzanol, a prevalent compound in pigmented rice varieties, has been reported to ameliorate obesity-associated metabolic disorders. Antiadipogenic activities of γ-oryzanol were determined in human adipose-derived mesenchymal stem cells and mouse-derived 3T3-L1 cells. γ-Oryzanol significantly decreased lipid accumulation and reduced glycerol-3-phosphate dehydrogenase activities in both adipocytes. In addition, γ-oryzanol in four pigmented rice varieties (black with giant embryo, brown, sugary brown, and red) was stable when stored at 4°C and also at room temperature for 22 weeks, whereas other bioactives such as lutein and ß-carotene were stable only at -80°C. Furthermore, the yield of γ-oryzanol from these rice varieties was significantly increased through steaming and roasting processes. Therefore, γ-oryzanol exerts antiadipogenic activity by suppressing adipocyte differentiations and is stable in pigmented rice for an extended period of time during storage and after cooking. Thus, the intake of pigmented rice may be a useful strategy for preventing obesity.
Subject(s)
Adipogenesis/drug effects , Oryza/chemistry , Phenylpropionates/pharmacology , 3T3-L1 Cells , Adipocytes/drug effects , Adipose Tissue/cytology , Animals , Cell Line , Drug Stability , Food Handling/methods , Food Preservation/methods , Hot Temperature , Humans , Mesenchymal Stem Cells/drug effects , Mice , Obesity/prevention & control , Phenylpropionates/analysis , Pigments, Biological , Seeds/chemistry , TemperatureABSTRACT
Peripheral blood monocytes obtained from paracoccidioidomycosis patients and healthy individuals were preactivated with recombinant gamma interferon (IFN-gamma) in different concentrations (250, 500 and 1000 U/ml) and evaluated for fungicidal activity against Paracoccidiodes brasiliensis strain 18 (Pb 18, high-virulence strain) and strain 265 (Pb 265, low-virulence strain) by plating of cocultures and counting of colony-forming units, after 10 d. Monocytes from healthy individuals failed to present fungicidal activity against P. brasiliensis even after IFN-gamma activation at the three concentrations. However, patient monocytes activated with IFN-gamma (1000 U/ml) showed a significant fungicidal activity when compared to that obtained with non-activated or activated cells with other IFN-gamma concentrations (250 and 500 U/ml). Moreover, patient monocytes presented higher fungicidal activity than the control, even before the activation process. These results may be explained by the activation state of patients' cells as a function of the in vivo contact with the fungus, which was confirmed by their higher capacity to release H(2)O(2) in vitro. Unlike the results obtained with Pb 18, patient and control cells presented a significant fungicidal activity against Pb 265, after priming with IFN- gamma. These results are explained by the higher levels of TNF-alpha in supernatants of cultures challenged with Pb 265. Moreover, higher levels of the cytokine were obtained in patient cell supernatants. Taken together, our results suggest that for effective killing of P. brasiliensis by monocytes, an initial activation signal induced by IFN-gamma is necessary to stimulate the cells to produce TNF-alpha. This cytokine may be involved, through an autocrine pathway, in the final phase activation process. The effectiveness of this process seems to depend on the virulence of the fungal strain and the activation state of the challenged cells.
Subject(s)
Interferon-gamma/pharmacology , Monocytes/immunology , Paracoccidioides/pathogenicity , Paracoccidioidomycosis/immunology , Tumor Necrosis Factor-alpha/metabolism , Cells, Cultured , Coculture Techniques , Colony Count, Microbial , Humans , Hydrogen Peroxide/metabolism , Monocytes/drug effects , Monocytes, Activated Killer/immunology , Monocytes, Activated Killer/metabolism , Paracoccidioides/immunology , Paracoccidioidomycosis/microbiology , Recombinant Proteins , VirulenceABSTRACT
Patients with paracoccidioidomycosis (PCM) present marked involvement of the lungs during the course of the mycosis. The purpose of this work was to obtain bronchoalveolar lavage (BAL) fluid from these patients to study the cytopathology, TNF levels and the oxidative and fungicidal response of alveolar macrophages (AMs) to in vitro incubation with recombinant IFN-gamma. To compare the lung and blood compartments, these determinations were also made in plasma and blood monocytes (BMs) obtained from the same patients. The cytopathology of BAL fluid revealed a predominance of macrophages, but with the presence of neutrophil exudation, and rare lymphocytes and epithelioid and giant cells. Comparison of the oxidative status and fungicidal activity of AMs and circulating BMs demonstrated that both cell types are highly activated for these two functions when compared to control cells. However, TNF levels were higher in BAL fluid than in plasma. The possible mechanisms involved in the hyperresponsiveness of cells from PCM patients are discussed.
Subject(s)
Bronchoalveolar Lavage Fluid/immunology , Interferon-gamma/pharmacology , Macrophages, Alveolar/drug effects , Monocytes/drug effects , Paracoccidioidomycosis/pathology , Tumor Necrosis Factor-alpha/metabolism , Humans , Macrophages, Alveolar/immunology , Monocytes/immunology , Paracoccidioides/immunology , Paracoccidioidomycosis/immunology , Paracoccidioidomycosis/microbiology , Recombinant ProteinsABSTRACT
Bioactive components in rice vary depending on the variety and growing condition. Fat-soluble components such as γ-oryzanol, tocopherols, tocotrienols, carotenoids, and fatty acids were analyzed in brown, sugary brown, red, and black rice varieties using established high-performance liquid chromatography (HPLC) and GC methodologies. In addition, these colored rice varieties were further analyzed using a high-resolution liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) (LTQ-Orbitrap XL) to identify the [M-H](-) ions of γ-oryzanol, ranging from m/z 573.3949 to 617.4211. The highest content of tocopherols (α-, 1.5; γ-, 0.5 mg/100 g) and carotenoids (lutein 244; trans-ß carotene 25 µg/100 g) were observed in black rice; tocotrienols (α-, 0.07; γ-, 0.14 mg/100 g) in red rice, and γ-oryzanol (115 mg/100 g) in sugary brown rice. In all colored rice varieties, the major fatty acids were palmitic (16:0), oleic (18:1n-9), and linoleic (18:2n-6) acids. When the γ-oryzanol components were further analyzed by LC-MS/MS, 3, 10, 8, and 8 triterpene alcohols or sterol ferulates were identified in brown, sugary brown, red, and black rice varieties, respectively. Such structural identification can lead to the elucidation of biological function of each component at the molecular level. Consumption of colored rice rich in beneficial bioactive compounds may be a useful dietary strategy for achieving optimal health.
Subject(s)
Oryza/chemistry , Plant Extracts/chemistry , Carotenoids/chemistry , Chromatography, High Pressure Liquid , Color , Fatty Acids/chemistry , Oryza/classification , Phenylpropionates/chemistry , Seeds/chemistry , Seeds/classificationABSTRACT
Patients undergoing surgical procedure develop an inflammatory response due to surgical trauma that may be modulated by anesthetics. The aim of this study was to investigate the cytokine profile in the plasma of adult patients who underwent minimally invasive surgery with balanced anesthesia with propofol, fentanyl, and sevoflurane. The study included 15 healthy patients scheduled for tympanoplasty or septoplasty under balanced anesthesia. Blood samples were drawn at four time points: before anesthesia, before surgery, 120 min after anesthesia induction, and on the first postoperative day. Plasma interleukin (IL)-1ß, -2, -4, -6, -8, -10, -12, TNF-α, and INF-γ levels were assessed by flow cytometry. IL-6 levels were elevated on the day after the surgery (p < 0.001). All other cytokines did not change either during or after balanced anesthesia (p > 0.05). In conclusion, balanced anesthesia with propofol, fentanyl, and sevoflurane anesthesia is not associated with intraoperative changes in the plasma cytokines in healthy patients undergoing minimally invasive otorhinological surgeries. Considering IL-6 results, a postoperative inflammatory response may have occurred due to surgical stress.
Subject(s)
Balanced Anesthesia , Cytokines/blood , Inflammation/blood , Minimally Invasive Surgical Procedures , Adult , Anesthetics, Inhalation/pharmacology , Anesthetics, Intravenous/pharmacology , Female , Fentanyl/administration & dosage , Humans , Male , Methyl Ethers/administration & dosage , Propofol/administration & dosage , Sevoflurane , TympanoplastyABSTRACT
An L-amino acid oxidase (BjarLAAO-I) from Bothrops jararaca snake venom was highly purified using a stepwise sequential chromatography on Sephadex G-75, Benzamidine Sepharose and Phenyl Sepharose. Purified BjarLAAO-I showed a molecular weight around 60,000 under reducing conditions and about 125,000 in the native form, when analysed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gel filtration, respectively. BjarLAAO-I is a homodimeric acidic glycoprotein, pI approximately 5.0, and N-terminal sequence showing close structural homology with other snake venom LAAOs. The purified enzyme catalysed the oxidative deamination of L-amino acids, the most specific substrate being L-Phe. Five amino acids, L-Ser, L-Pro, L-Gly, L-Thr and L-Cys were not oxidized, clearly indicating a significant specificity. BjarLAAO-I significantly inhibited Ehrlich ascites tumour growth and induced an influx of polymorphonuclear cells, as well as spontaneous liberation of H(2)O(2) from peritoneal macrophages. Later, BjarLAAO-I induced mononuclear influx and peritoneal macrophage spreading. Animals treated with BjarLAAO-I showed higher survival time.
Subject(s)
Antineoplastic Agents/pharmacology , Bothrops , Carcinoma, Ehrlich Tumor/drug therapy , Crotalid Venoms/enzymology , L-Amino Acid Oxidase/pharmacology , Amino Acids/metabolism , Animals , Carcinoma, Ehrlich Tumor/enzymology , Carcinoma, Ehrlich Tumor/pathology , Cell Movement/drug effects , Cell Movement/physiology , Crotalid Venoms/chemistry , Drug Screening Assays, Antitumor , Hydrogen Peroxide/metabolism , L-Amino Acid Oxidase/chemistry , L-Amino Acid Oxidase/isolation & purification , Macrophages, Peritoneal/drug effects , Macrophages, Peritoneal/physiology , Male , Mice , Neutrophils/drug effects , Neutrophils/pathology , Oxidation-Reduction , Sequence Alignment , Sequence Analysis, Protein , Species SpecificityABSTRACT
The production of prostaglandins (PGs) during fungal infections could be an important suppressor factor of host immune response. Host cells are one source of prostaglandin E(2) (PGE(2)); however another potential source of PGE(2) is the fungal pathogen itself. Thus, both host and fungal PGE2 production is theorized to play a role in pathogenesis, being critical for growth of the fungus and to modulate the host immune response. The purpose of this work was to investigate if high and low virulent strains of Paracoccidioides brasiliensis have the capacity to produce PGE(2) in vitro, and if this production was related to the fungal growth. The results demonstrated that both strains of P. brasiliensis produce high levels of PGE(2) and the treatment with indomethacin, a cyclooxygenase inhibitor, significantly reduced the production of this mediator, as well as the viability of the fungus. Thus, our data indicate that PGE(2) is produced by P. brasiliensis by a cyclooxygenase-dependent metabolic pathway, and its production is required for fungal survival. This discovery reveals an important factor that has potentially great implications for understanding the mechanisms of immune deviation during infection.
Subject(s)
Dinoprostone/biosynthesis , Paracoccidioides/metabolism , Paracoccidioides/pathogenicity , Animals , Cyclooxygenase Inhibitors/pharmacology , Indomethacin/pharmacology , Mice , Paracoccidioides/growth & development , VirulenceABSTRACT
We previously demonstrated that Bothrops jararaca venom (BjV) has an antitumor effect on Ehrlich ascites tumor (EAT) cells and induces an increase of polymorphonuclear leukocytes in early stages of tumor growth. It has been reported that this venom presents an important inflammatory effect when inoculated in animal models and in human snakebites, and that cytokine levels have been detected in these cases. To evaluate whether the cytokines can be involved with the suppression of the tumoral growth, we evaluate the cytokine profile in the peritoneal cavity of mice inoculated with EAT cells and treated with BjV. Swiss mice were inoculated with EAT cells by the intraperitoneal route and treated with BjV venom (0.4 mg/kg, intraperitoneally), on the 1st, 4th, 7th, 10th, and 13th day. Mice were evaluated for cytokine levels on the 2nd, 5th, 8th, 11th and 14th day. Analysis was performed using an enzyme-linked immunosorbent assay for interleukin (IL)-1alpha, IL-2, IL4, IL-6, IL-10, IL-13, and tumor necrosis factor-alpha (TNF-alpha) levels in the peritoneal washing supernatant. Results were analyzed statistically by the Kruskal-Wallis and Dunn's tests at the 5% level of significance. We observed that EAT implantation induces IL-6 production on the 11th and 14th days of tumor growth, IL-10 on the 11th day and TNF-alpha on the 14th day. The treatment with BjV suppresses production of these cytokines. In addition, IL-13 was produced by animals that were inoculated only with venom on the 11th and 14th days, and by the group inoculated with EAT cells and treated with venom on the 2nd and 14th days. Furthermore, we suggest that the IL-6 detected in the present study is produced by the EAT cells and the suppression of its production could be associated with the antitumor effect of BjV.
Subject(s)
Carcinoma, Ehrlich Tumor/immunology , Crotalid Venoms/therapeutic use , Cytokines/biosynthesis , Animals , Carcinoma, Ehrlich Tumor/therapy , Interleukin-10/biosynthesis , Interleukin-13/biosynthesis , Interleukin-6/biosynthesis , Male , Mice , Tumor Necrosis Factor-alpha/biosynthesisABSTRACT
Many experimental studies have been carried out using snake venoms for the treatment of animal tumors, with controversial results. While some authors have reported an antitumor effect of treatment with specific snake venom fractions, others have reported no effects after this treatment. The aim of this study was to evaluate the effect of Bothrops jararaca venom (BjV) on Ehrlich ascites tumor (EAT) cells in vivo and in vitro. In the in vivo study, Swiss mice were inoculated with EAT cells by the intraperitoneal (i.p.) route and treated with BjV venom (0.4 mg/kg, i.p.), on the 1st, 4th, 7th, 10th, and 13th days. Mice were evaluated for total and differential cells number on the 2nd, 5th, 8th, 11th and 14th days. The survival time was also evaluated after 60 days of tumor growth. In the in vitro study, EAT and normal peritoneal cells were cultivated in the presence of different BjV concentrations (2.5, 5.0, 10.0, 20.0, 40.0, and 80 microg) and viability was verified after 3, 6, 12 and 24 h of cultivation. Results were analyzed statistically by the Kruskal-Wallis and Tukey tests at the 5% level of significance. It was observed that in vivo treatment with BjV induced tumor growth inhibition, increased animal survival time, decreased mortality, increased the influx of polymorphonuclear leukocytes on the early stages of tumor growth, and did not affect the mononuclear cells number. In vitro treatment with BjV produced a dose-dependent toxic effect on EAT and peritoneal cells, with higher effects against peritoneal cells. Taken together, our results demonstrate that BjV has an important antitumor effect. This is the first report showing this in vivo effect for this venom.
Subject(s)
Antineoplastic Agents/pharmacology , Crotalid Venoms/pharmacology , Animals , Carcinoma, Ehrlich Tumor/drug therapy , Cell Survival/drug effects , Male , Mice , Neutrophils/drug effects , Neutrophils/physiologyABSTRACT
Snake venoms have been used as antineoplastic substances in several experimental models. We demonstrated in previous studies that Bothrops jararaca venom (BjV) induces inhibition of Ehrlich ascites tumor (EAT) growth accompanied by an increase of mononuclear (MN) leukocytes in all groups inoculated with EAT and/or venom. The objective of the present study was to characterize the subpopulations of MN leukocytes involved in the inhibition of EAT growth by treatment with BjV. Swiss mice were inoculated with 1.0x10(3) EAT cells by the intraperitoneal route and treated with 0.4 mg/kg of BjV by the same route (Group TV). Treatment was started 24 h after tumor cell inoculation and consisted of five intraperitoneal injections performed at 72 h intervals. After 2, 8 and 14 days, groups of animals were sacrificed and the number of B, TCD4 and TCD8 lymphocytes, macrophages and natural killer cells present in the peritoneal cavity was determined by flow cytometry. The control group consisted of animals inoculated with EAT and treated with 0.1 ml of saline under the same conditions as the experimental group (Group T). Two additional control groups consisted of animals not inoculated with EAT and treated with saline or venom. Data were analyzed statistically by the Kruskal-Wallis non-parametric test for independent samples. On the 2nd and 8th day we observed a difference between groups T and TV (group T > group TV) for all cell types, except natural killer cells, that only differed on the 2nd day. However, on the 14th day there was no difference in MN cells among groups. These data suggest that the inhibition of EAT is related to the toxic action of BjV on tumor cells and/or to the proteolytic effect of the venom on the mediators produced by the cells for growth modulation.
Subject(s)
Bothrops , Carcinoma, Ehrlich Tumor/pathology , Crotalid Venoms/pharmacology , Leukocytes, Mononuclear/pathology , Animals , B-Lymphocytes/pathology , CD4-Positive T-Lymphocytes/pathology , CD8-Positive T-Lymphocytes/pathology , Cell Division/drug effects , Flow Cytometry , Male , Mice , Neoplasm Transplantation , Peritoneal Cavity/pathology , Time FactorsABSTRACT
Vinte e sete pacientes portadores de paracoccidioidomicose (PCM) foram tratados com itraconazole (100-200 mg/dia no primeiro mes e 100 mg/dia ate 6-8 meses) e avaliados sob o ponto de vista clínico e sorológico, ate 3 e meio anos após o início do tratamento, utilizando-se os testes de Dot-blot e ELISA para medir os titulos de anticorpos IgG, IgA e IgM anti-P brasiliensis, e Western-blot para determinar os anticorpos IgG, IgA e IgM contra os componentes antigenicos do fungo. Antes do tratamento, 81,5 por cento (Dot-blot) e 84 por cento (ELISA) dos pacientes apresentaram titulos elevados de anticorpos IgG anti-P. brasiliensis, que decresceram levemente com o tratamento...
Subject(s)
Humans , Male , Female , Adolescent , Child , Adult , Middle Aged , Itraconazole/therapeutic use , Paracoccidioidomycosis/therapy , Blotting, Western , Enzyme-Linked Immunosorbent Assay , Follow-Up Studies , Immunoblotting , Immunoglobulin A/immunology , Immunoglobulin G/immunology , Immunoglobulin M/immunologyABSTRACT
The objectives of the present study were to optimize the protocol of mouse immunization with Paracoccidioides brasiliensis antigens (Rifkind's protocol) and to test the modulation effect of cyclophosphamide (Cy) on the delayed hypersensitivity response (DHR) of immunized animals. Experiments were carried out using one to four immunizing doses of either crude particulate P. brasiliensis antigen or yeast-cell antigen, followed by DHR test four or seven days after the last immunizing dose. The data demonstrated that an immunizing dose already elicited response; higher DHR indices were obtained with two or three immunizing doses; there were no differences between DHR indices of animals challenged four or seven days after the last dose. Overall the inoculation of two or three doses of the yeast-cell antigen, which is easier to prepare, and DHR test at day 4 simplify the original Rifkind's immunization protocol and shorten the duration of the experiments. The modulation effect of Cy on DHR was assayed with administration of 2.5, 20 and 100 mg/kg weight at seven day intervals starting from day 4 prior to the first immunizing dose. Only the treatment with 2.5 mg Cy increased the DHR indices. Treatment with 100 mg Cy inhibited the DHR, whereas 20 mg Cy did not affect the DHR indices. Results suggest an immunostimulating effect of low dose of Cy on the DHR of mice immunized with P. brasiliensis antigens.