The Immunomodulatory effects of abortion-prone mice decidual and serum soluble factors on macrophages and splenocytes

Cytokine profile and nitric oxide levels in peritoneal macrophages of BALB/c mice exposed to the fucose-mannose ligand of Leishmania infantum combined with glycyrrhizin

Background

The fucose-mannose ligand (FML) of Leishmania infantum is a complex glycoprotein which does not elicit adequate immunogenicity in humans. In recent years, adjuvant compounds derived from plants have been used for improving the immunogenicity of vaccines. Glycyrrhizin (GL) is a natural triterpenoid saponin that has known immunomodulatory activities. In the present study, we investigated the effects of co-treatment with FML and GL on the production of cytokines and nitric oxide (NO) by macrophages, in vitro.

Methods

Lipopolysaccharide (LPS) stimulated murine peritoneal macrophages were treated with FML (5 μg/ml) of L. infantum and various concentrations of GL (1 μg/ml, 10 μg/ml and 20 μg/ml). After 48 h of treatment, cell culture supernatants were recovered and the levels of TNF-α, IL-10, IL-12p70 and IP-10 were measured by sandwich ELISA and NO concentration by Griess reaction.

Results

Our results indicate that the treatment of activated macrophages with FML plus GL leads to enhanced production of NO, TNF-α and IL-12p70, and reduction of IL-10 levels in comparison with FML treatment alone.

Conclusions

Therefore, we concluded that GL can improve the immunostimulatory effect of FML on macrophages and leads to their polarization towards an M1-like phenotype.

Cytokine profile and nitric oxide levels in macrophages exposed to Leishmania infantum FML

Fucose-mannose ligand (FML) is a soluble antigen purified from Leishmania donovani complex and used for diagnosis, prognosis, and vaccine development against visceral leishmaniasis (VL). We aimed to explore the effects of FML on the production of cytokines, chemokines and nitric oxide (NO) by macrophages in vitro. Peritoneal macrophages from BALB/c mice were treated with various concentrations of FML purified from Leishmania infantum in the absence or presence of LPS Peritoneal macrophages. After 48hr, cell culture supernatants were recovered and the levels of TNF-α, IL-10, IL-12p70 and IP-10 measured by Sandwich ELISA and NO concentration by Griess reaction. We found that FML significantly increase NO, IL-12p70 and IP-10 production in both LPS-treated and untreated macrophages and increase IL-10 levels only in LPS-treated macrophages. However, FML could not alert TNF-α levels in both LPS-treated and untreated macrophages. Further analysis revealed that FML can also increase IL-12p70/IL-10 ratio in LPS-treated macrophages. We concluded that FML can polarize macrophages to an appropriate phenotype similar to M1 phenotype against Leishmania donovani complex, although IL10 and TNF results are controversial.

Pregnancy outcomes following the administration of high doses of dexamethasone in early pregnancy

OBJECTIVE

In the present study, we aimed to evaluate the effects of high doses of dexamethasone (DEX) in early pregnancy on pregnancy outcomes.

METHODS

Pregnant BALB/c mice were treated with high-dose DEX in the experimental group or saline in the control group on gestational days (GDs) 0.5 to 4.5. Pregnant mice were sacrificed on GDs 7.5, 13.5, or 18.5 and their peripheral blood, placentas, fetuses, and uterine tissue were collected. Decidual and placenta cell supernatants were examined to evaluate the effect of DEX on the proliferation of mononuclear cells, the quantity of uterine macrophages and uterine natural killer (uNK) cells, and levels of progesterone and 17β-estradiol, as determined by an 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide assay, immunohistochemistry, and enzyme-linked immunosorbent assay, respectively. We also were measured fetal and placental growth parameters on GD 18.5.

RESULTS

We found that high doses of DEX were associated with an increased abortion rate, enhancement of the immunosuppressive effect of the decidua, alterations in placental growth parameters, decreased progesterone and 17β-estradiol levels, and a reduced frequency of macrophages and uNK cells.

CONCLUSION

Our data suggest that the high-dose administration of DEX during early pregnancy negatively affected pregnancy outcomes.