Urethral reconstruction is one of the great surgical challenges for urologists. A cell-based tissue-engineered urethra may be an alternative for patients who have complicated long strictures and need urethral reconstruction. Here, we demonstrated the feasibility of using autologous urine-derived stem cells (USCs) seeded on small intestinal submucosa (SIS) to repair a urethral defect in a rabbit model. Autologous USCs were obtained and characterized, and their capacity to differentiate into urothelial cells (UCs) and smooth muscle cells (SMCs) was tested. Then, USCs were labeled with PKH67, seeded on SIS, and transplanted to repair a urethral defect. The urethral defect model was surgically established in New Zealand white male rabbits. A ventral urethral gap was created, and the urethral mucosa was completely removed, with a mean rabbit penile urethra length of 2 cm. The urethral mucosal defect was repaired with a SIS scaffold (control group: SIS with no USCs; experimental group: autologous USC-seeded SIS; n = 12 for each group). A series of tests, including a retrograde urethrogram, histological analysis, and immunofluorescence, was undertaken 2, 3, 4, and 12 weeks after the operation to evaluate the effect of the autologous USCs on urethral reconstruction. Autologous USCs could be easily collected and induced to differentiate into UCs and SMCs. In addition, the urethral caliber, speed of urothelial regeneration, content of smooth muscle, and vessel density were significantly improved in the group with autologous USC-seeded SIS. Moreover, inflammatory cell infiltration and fibrosis were found in the control group with only SIS, but not in the experimental autologous USC-seeded SIS group. Furthermore, immunofluorescence staining demonstrated that the transplanted USCs differentiated into UCs and SMCs in vivo. Autologous USCs can be used as an alternative cell source for cell-based tissue engineering for urethral reconstruction.

Although it has been demonstrated that cAMP pathway affect both adaptive and innate cell functions, the role of this pathway in the regulation of T-cell-mediated central nervous system (CNS) autoimmune inflammation, such as in experimental autoimmune encephalomyelitis (EAE), remains unclear. It is also unclear how cAMP pathway affects the function of CD4 T cells in vivo at the site of inflammation. We found that adenylyl cyclase activator Forskolin besides inhibition of functions autoimmune CD4 T cells also upregulated microRNA (miR)-124 in the CNS during EAE, which is associated with M2 phenotype of microglia/macrophages. Our study further established that in addition to direct influence of cAMP pathway on CD4 T cells, stimulation of this pathway promoted macrophage polarization toward M2 leading to indirect inhibition of function of T cells in the CNS. We demonstrated that Forskolin together with IL-4 or with Forskolin together with IL-4 and IFNγ effectively stimulated M2 phenotype of macrophages indicating high potency of this pathway in reprogramming of macrophage polarization in Th2- and even in Th1/Th2-mixed inflammatory conditions such as EAE. Mechanistically, Forskolin and/or IL-4 activated ERK pathway in macrophages resulting in the upregulation of M2-associated molecules miR-124, arginase (Arg)1, and Mannose receptor C-type 1 (Mrc1), which was reversed by ERK inhibitors. Administration of Forskolin after the onset of EAE substantially upregulated M2 markers Arg1, Mrc1, Fizz1, and Ym1 and inhibited M1 markers nitric oxide synthetase 2 and CD86 in the CNS during EAE resulting in decrease in macrophage/microglia activation, lymphocyte and CD4 T cell infiltration, and the recovery from the disease. Forskolin inhibited proliferation and IFNγ production by CD4 T cells in the CNS but had rather weak direct effect on proliferation of autoimmune T cells in the periphery and in vitro, suggesting prevalence of indirect effect of Forskolin on differentiation and functions of autoimmune CD4 T cells in vivo. Thus, our data indicate that Forskolin has potency to skew balance toward M2 affecting ERK pathway in macrophages and indirectly inhibit pathogenic CD4 T cells in the CNS leading to the suppression of autoimmune inflammation. These data may have also implications for future therapeutic approaches to inhibit autoimmune Th1 cells at the site of tissue inflammation.

Soil fungi are known to contain a rich variety of defense metabolites that allow them to compete with other organisms (fungi, bacteria, nematodes, and insects) and help them occupy more preferential areas at the expense of effective antagonism. These compounds possess antibiotic activity towards a wide range of other microbes, particularly fungi that belong to different taxonomical units. These compounds include peptaibols, which are non-ribosomal synthesized polypeptides containing non-standard amino acid residues (alpha-aminoisobutyric acid mandatory) and some posttranslational modifications. We isolated a novel antibiotic peptide from the culture medium of Emericellopsis alkalina, an alkalophilic strain. This peptide, called emericellipsin A, exhibited a strong antifungal effect against the yeast Candida albicans, the mold fungus Aspergillus niger, and human pathogen clinical isolates. It also exhibited antimicrobial activity against some Gram-positive and Gram-negative bacteria. Additionally, emericellipsin A showed a significant cytotoxic effect and was highly active against Hep G2 and HeLa tumor cell lines. We used NMR spectroscopy to reveal that this peptaibol is nine amino acid residues long and contains non-standard amino acids. The mode of molecular action of emericellipsin A is most likely associated with its effects on the membranes of cells. Emericellipsin A is rather short peptaibol and could be useful for the development of antifungal, antibacterial, or anti-tumor remedies.