The immune response to Hymenolepis nana in mice decreases tumorigenesis induced by 7,12 dimethylbenz-anthracene.

BACKGROUND: Cancer is a high-impact disease throughout the world. A negative correlation has been established between the development of cancer and the Th2 immune response. Infection by helminth parasites is characterized by the induction of a strong and long-lasting Th2 response. The aim of this work was to evaluate the effect of the immune response induced by the infection with the helminth Hymenolepis nana, on the tumorigenesis induced by dimethylbenz-anthracene (DMBA) in mice. METHODOLOGY: Four different groups of 14 female BALB/c mice were formed; Group A, dimethyl sulfoxide (DMSO) (vehicle) was administered cutaneously, Group B infected with H. nana, group C, cutaneously DMBA and finally Group D infected with H. nana and cutaneous DMBA. The tumor load was determined in those animals that developed cancerous lesions. In all groups were determined: serum concentration of IgE, IFNγ, IL-10, IL-5 and malondialdehyde (MDA). The inflammatory infiltrate was analyzed from skin samples and the expression of the main eosinophilic protein and myeloperoxidase was determined. RESULTS: The group previously infected with H. nana had a reduced amount of tumors with smaller size, in comparison to the group that received only DMBA; this reduction was associated with lower levels of IFNγ and IL-10, while levels of IgE, IL-5 and MDA were higher. Further, the number of eosinophils and neutrophils was statistically higher in the animals that were previously infected with the helminth and developed less tumors. CONCLUSION: The immune response induced by H. nana infection is associated with the reduction of tumors probably due to the activity of eosinophils and neutrophils.

Reduction of respiratory infections in asthma patients supplemented with vitamin D is related to increased serum IL-10 and IFNγ levels and cathelicidin expression.

BACKGROUND: Vitamin D is a molecule that modulates the immune response and shows anti-inflammatory effects that are beneficial for the control of chronic diseases such as asthma. The trial aim was to explore the effect of vitamin D supplementation on the colonization of pathogenic bacteria in the upper respiratory tract of allergic asthmatic patients. METHODS: This study was conducted in 86 patients between 18 and 50 years of age who were randomly divided into two groups. Both groups received the treatment recommended by the Global Initiative for Asthma (GINA). One group also received calcitriol (1,25-(OH)2D3), and the other group received a placebo. At baseline and 6 months, skin prick tests were conducted, pharyngeal bacterial cultures were performed, and cathelicidin LL-37 was measured in sputum. Serum levels of IgE, eosinophils, IL-5, IL-9, IL-10, IL-13, and IFNγ were quantified at the beginning and the end of the study. RESULTS: Serum levels of IL-10 and IFNγ increased significantly in the group of patients with vitamin D supplementation, while IL-5, IL-9, and IL-13 decreased significantly. At the end of the trial, IgE and eosinophil levels significantly decreased but allergen sensitivity did not show any changes from baseline. Respiratory infections were drastically reduced, and this decrease was related to the number of patients who had high serum levels of IL-10 and IFNγ and expressed LL-37 in their sputum. CONCLUSION: Treatment of asthma patients with vitamin D reduced respiratory infections, and this effect was related to the increase of cathelicidin LL-37.

Effect of 1,25(OH)2D3 on BALB/c mice infected with Leishmania mexicana.

The most active metabolite of vitamin D, 1,25(OH)2D3 is a steroid hormone implicated in a wide range of cell functions such as differentiation, proliferation and apoptosis. Leishmania mexicana causes two kinds of cutaneous leishmaniasis: localized or diffuse. In this work we explored the effect of treatment of 1,25(OH)2D3 on a susceptible leishmaniasis mice model. A significant reduction in the lesion size was found in animals treated with 1,25(OH)2D3. Well preserved tissue and presence of large numbers of eosinophils and fibroblasts was found in the group treated with 1,25(OH)2D3. By contrast, destroyed epidermis was observed with large amount of neutrophils and epithelioid macrophages, on infected groups without 1,25(OH)2D3 treatment. The production of pro-inflammatory cytokines in mice infected and treated with 1,25(OH)2D3 was lower than the animals infected without 1,25(OH)2D3 treatment. Interestingly, there were no differences in the number of parasites in both groups. Finally, the amount of collagen was higher in animals with treatment compare with animals without 1,25(OH)2D3 treatment. In summary, mice treated with 1,25 (OH) 2D3 reflect a healing process without elimination of L. mexicana.

Culture of an epithelial cell line (MDCK) with a serum substitute.

This paper reports the suitability of culturing a line of dog kidney epithelial cells, MDCK, in the presence of a serum substitute, Ultroser G. Serial subcultivation with this product was possible for at least 10 passages without any change in cell shape and size, saturation density, dome-forming ability, transepithelial resistance, and growth curve. Adhesion of newly plated cells to plastic was somewhat lower than in fetal calf serum but the trypsin-harvesting kinetics were essentially the same. However, the membrane ion transport system was altered: cell sodium influx was greatly diminished, suggesting a deep change in the amiloride-sensitive Na+ channels; sodium efflux was highly enhanced (both active and passive).