Directed differentiation of regulatory T cells from naive T cells and prevention of their inflammation-mediated instability using small molecules.

Regulatory T (Treg ) cell therapy is a promising approach for immune tolerance induction in autoimmunity conditions and cell/organ transplantations. Insufficient isolation yields and impurity during downstream processes and Treg instability after adoptive transfer in inflammatory conditions are major limitations to Treg therapy, and indicate the importance of seeking a valid, reliable method for de-novo generation of Tregs . In this research, we evaluated Treg -like cells obtained from different Treg differentiation protocols in terms of their yield, purity and activity. Differentiation was performed on naive CD4+ cells and a naive CD4+ /Treg co-culture by using three different protocols - ectopic expression of forkhead box protein P3 (E-FoxP3), soluble transforming growth factor ß (S-TGF) and small molecules [N-acetyl puromycin and SR1555 (N-Ac/SR)]. The results showed that a high yield of a homogeneous population of Treg -like cells could be achieved by the N-Ac/SR method under a T helper type 17 (Th17)-polarizing condition, particularly interleukin (IL)-6 and TGF-ß, when compared with the E-FoxP3 and S-TGF methods. Surprisingly, SR completely inhibited the differentiation of IL-17-producing cells and facilitated Treg generation in the inflammatory condition and had highly suppressive activity against T cell proliferation without Treg -specific demethylase region (TSDR) demethylation. For the first time, to our knowledge, we report the generation of efficient, pure Treg -like cells by using small molecules during in-vitro inflammatory conditions. Our results suggested that the N-Ac/SR method has several advantages for Treg generation when compared with the other methods, including a higher purity of Tregs , easier procedure, superior suppressive activity during the inflammatory condition and decreased cost.

Effects of enriched environment on alterations in the prefrontal cortex GFAP- and S100B-immunopositive astrocytes and behavioral deficits in MK-801-treated rats.

A plethora of studies have indicated that enriched environment (EE) paradigm provokes plastic and morphological changes in astrocytes with accompanying increments of their density and positively affects the behavior of rodents. We also previously documented that EE could be employed to preclude several behavioral abnormalities, mainly cognitive deficits, attributed to postnatal N-methyl-d-aspartate (NMDA) receptor antagonist (MK-801) treatment, as a rodent model of schizophrenia (SCH) aspects. Given this, the current study quantitatively investigated the number of cells, presumed to be astrocytes, expressing two astroglia-associated proteins (S100B and glial fibrillary acidic protein (GFAP)) by immunohistochemistry in the prefrontal cortex (PFC), along with anxiety and passive avoidance (PA) learning behaviors by utilizing elevated plus maze (EPM) and shuttle-box tests, in MK-801-treated male wistar rats submitted to EE and non-EE rats. Following a treatment regime of sub-chronic MK-801 (1.0mg/kg i.p. daily for five consecutive days from postnatal day (P) 6), S-100B-positive cells and anxiety level were markedly increased, while the GFAP-positive cells and PA learning were notably attenuated. The trend of diminished GFAP-immunopositive cells and elevated S100B-immunostained cells in the PFC was reversed in the SCH-like rats by exposure of animals to EE, commencing from birth up to the time of experiments on P28-85. Additionally, EE exhibited an ameliorating effect on the behavioral abnormalities evoked by MK-801. Overall, present findings support that improper astrocyte functioning and behavioral changes, reminiscent of the many facets of SCH, occur consequential to repetitive administration of MK-801 and that raising rat pups in an EE mitigates these alterations.

Antimutagenic effects of vitamin E on oncology and non oncology hospital nurses by comet assay.

Vitamin E is a natural antioxidant and its most common biologically active form is α-tocopherol. The antiproliferative effects of α-tocopherol have been previously demonstrated. In this study the antimutagenic effects of vitamin E on oncology and non oncology hospital nurses was investigated. A total of 138 female nurses from oncology and non oncology hospitals participated in the study. They received 200 mg/day vitamin E for 2 weeks. The urine samples before and after intake of vitamin E were collected and the nucleus of urothelial cells were evaluated with comet assay. The length of epithelial cells nuclei correlated with increased fracture rate of DNA. Nucleolus length of urine epithelial cells of all nursing staff before and after vitamin E treatment were measured and the data were evaluated by student t-test and SPSS. Our study showed that 20% of nursing staff have apoptosis and DNA fracture in the nucleolus of their urine epithelial cells and DNA damage in the urothelial cells of exposed nurses was significantly higher than the control group (P<0.05).The antimutagenic activity of vitamin E had significant effects on oncology hospital nurses effectively in repairing DNA damage and decreasing their nucleus length in urine epithelial cells.We propose that the higher therapeutic doses of vitamin E and increasing the length of treatment period will be effective against DNA strand breakage and may have more effect on oncology nurses.

Cytologic features of "dry-type" cutaneous leishmaniasis.

Exfoliative cytology smears from the lesions of 179 patients with cutaneous leishmaniasis due to Leishmania tropica were studied with specific reference to cellular reactions and their effect on the parasite. Aggregates of the parasite (so-called Leishmania Donovan bodies) were present within macrophages and in some fibroblasts. The nature of the inflammatory reaction to the disease was studied by performing differential counts of the inflammatory cells present in the smears. These were correlated with the number of Leishman Donovan bodies. There was an inverse relationship between the number of Leishman Donovan bodies and the percentage of small lymphocytes, neutrophils, and type I macrophages. It is postulated that aggregates of activated macrophages (designated types II and III) and the Leishmanian milieu (sticky matrix) protect the amastigote Leishmania parasites from being eradicated by the inflammatory and immune reaction. The cytoplasmic blebbing of the parasitophorous vacuoles and cell to cell connection of the activated histiocytes could be shown by the CD-68 immunostaining of the tissue biopsy.