Epithelial cells from oral mucosa: How to cultivate them?

Epithelial cells from oral mucosa (EOM) are responsible for important functions, like the primary protection of oral mucosa against external aggressions building a mechanical barrier against microorganisms, mechanical damage, toxic material, thermal regulation and secretion of different classes of inflammatory mediators. EOM could be an interesting tool for cellular and molecular biology research. Usually, EOM are collected by a painful and invasive process. In this study, we propose an alternative method to cultivate EOM collected by non-invasive scraping method of oral mucosa. Papanicolaou staining showed mainly two kinds of epithelial cell population after EOM scraping. As result of the five culture methods tested here, our results revealed that the EOM were successfully cultured on a murine feeder layer. In addition, EOM could be frozen and thawed, without morphology changes and loss of viability. Our findings suggest that EOM can be considered as a good cell source for many purposes, such as genetic studies, diagnosis and cell therapy.

Fibroblast sources: Where can we get them?

Fibroblasts are cells widely used in cell culture, both for transient primary cell culture or permanent as transformed cell lines. Lately, fibroblasts become cell sources for use in disease modeling after cell reprogramming because it is easily accessible in the body. Fibroblasts in patients will maintain all genetic background during reprogramming into induced pluripotent stem cells. In spite of their large use, fibroblasts are obtained after an invasive procedure, a superficial punch skin biopsy, collected under patient's local anesthesia. Taking into consideration the minimum patient's discomfort during and after the biopsy procedure, as well as the aesthetics aspect, it is essential to reflect on the best site of the body for the biopsy procedure combined with the success of getting robust fibroblast cultures in the lab. For this purpose, we compared the efficiency of four biopsy sites of the body (skin from eyelid, back of the ear, abdominal cesarean scar and groin). Cell proliferation assays and viability after cryopreservation were measured. Our results revealed that scar tissue provided fibroblasts with higher proliferative rates. Also, fibroblasts from scar tissues presented a higher viability after the thawing process.

In-a-dish: induced pluripotent stem cells as a novel model for human diseases.

Human pluripotent stem cells bring promise in regenerative medicine due to their self-renewing ability and the potential to become any cell type in the body. Moreover, pluripotent stem cells can produce specialized cell types that are affected in certain diseases, generating a new way to study cellular and molecular mechanisms involved in the disease pathology under the controlled conditions of a scientific laboratory. Thus, induced pluripotent stem cells (iPSC) are already being used to gain insights into the biological mechanisms of several human disorders. Here we review the use of iPSC as a novel tool for disease modeling in the lab.

Identification of three distinguishable phenotypes in golden retriever muscular dystrophy.

Duchenne muscular dystrophy (DMD) is a human disease characterized by progressive and irreversible skeletal muscle degeneration caused by mutations in genes coding for important muscle proteins. Unfortunately, there is no efficient treatment for this disease; it causes progressive loss of motor and muscular ability until death. The canine model (golden retriever muscular dystrophy) is similar to DMD, showing similar clinical signs. Fifteen dogs were followed from birth and closely observed for clinical signs. Dogs had their disease status confirmed by polymerase chain reaction analysis and genotyping. Clinical observations of musculoskeletal, morphological, gastrointestinal, respiratory, cardiovascular, and renal features allowed us to identify three distinguishable phenotypes in dystrophic dogs: mild (grade I), moderate (grade II) and severe (grade III). These three groups showed no difference in dystrophic alterations of muscle morphology and creatine kinase levels. This information will be useful for therapeutic trials, because DMD also shows significant, inter- and intra-familiar clinical variability. Additionally, being aware of phenotypic differences in this animal model is essential for correct interpretation and understanding of results obtained in pre-clinical trials.