Generation of a human control iPS cell line (ESi080-A) from a donor with no rheumatic diseases.

Here, we report the establishment of the human iPS cell line N1-FiPS4F#7 generated from skin cells of a patient with no rheumatic diseases, thus obtaining an appropriate control iPS cell line for researchers working in the field of rheumatic diseases. The reprogramming factors Oct4, Sox2, Klf4 and c-Myc were introduced using a non-integrating reprogramming strategy involving Sendai Virus.

Usefulness of Mesenchymal Cell Lines for Bone and Cartilage Regeneration Research.

The unavailability of sufficient numbers of human primary cells is a major roadblock for in vitro repair of bone and/or cartilage, and for performing disease modelling experiments. Immortalized mesenchymal stromal cells (iMSCs) may be employed as a research tool for avoiding these problems. The purpose of this review was to revise the available literature on the characteristics of the iMSC lines, paying special attention to the maintenance of the phenotype of the primary cells from which they were derived, and whether they are effectively useful for in vitro disease modeling and cell therapy purposes. This review was performed by searching on Web of Science, Scopus, and PubMed databases from 1 January 2015 to 30 September 2019. The keywords used were ALL = (mesenchymal AND ("cell line" OR immortal*) AND (cartilage OR chondrogenesis OR bone OR osteogenesis) AND human). Only original research studies in which a human iMSC line was employed for osteogenesis or chondrogenesis experiments were included. After describing the success of the immortalization protocol, we focused on the iMSCs maintenance of the parental phenotype and multipotency. According to the literature revised, it seems that the maintenance of these characteristics is not guaranteed by immortalization, and that careful selection and validation of clones with particular characteristics is necessary for taking advantage of the full potential of iMSC to be employed in bone and cartilage-related research.

Induced pluripotent stem cells for cartilage repair: current status and future perspectives.

The establishment of cartilage regenerative medicine is an important clinical issue, but the search for cell sources able to restore cartilage integrity proves to be challenging. Human mesenchymal stromal cells (MSCs) are prone to form epiphyseal or hypertrophic cartilage and have an age-related limited proliferation. On the other hand, it is difficult to obtain functional chondrocytes from human embryonic stem cells (ESCs). Moreover, the ethical issues associated with human ESCs are an additional disadvantage of using such cells. Since their discovery in 2006, induced pluripotent stems cells (iPSCs) have opened many gateways to regenerative medicine research, especially in cartilage tissue engineering therapies. iPSCs have the capacity to overcome limitations associated with current cell sources since large numbers of autologous cells can be derived from small starting populations. Moreover, problems associated with epiphyseal or hypertrophic-cartilage formation can be overcome using iPSCs. iPSCs emerge as a promising cell source for treating cartilage defects and have the potential to be used in the clinical field. For this purpose, robust protocols to induce chondrogenesis, both in vitro an in vivo, are required. This review summarises the recent progress in iPSC technology and its applications for cartilage repair.

In vitro repair model of focal articular cartilage defects in humans.

Articular cartilage lesions, which do not affect the integrity of subchondral bone, are not able to be repaired spontaneously, thus inducing cartilage degeneration and developing an arthrosic process. To avoid the need for prosthetic replacement, different cell treatments were developed with the aim of generating a repaired tissue with structure, biochemistry composition, and functional behavior equal or similar to those of natural articular cartilage.The following protocols describe the methods for harvesting articular cartilage explants both from pig and human specimens and isolating and culturing pig chondrocytes. Moreover, the methodology for an in vitro model of xenoimplant of pig chondrocytes in focal defects of human articular cartilage is described.

Morphological study of root surfaces in teeth with adult periodontitis.

BACKGROUND: Our study correlates the histological alterations in the cementum (especially resorption areas) of teeth with the different stages of adult periodontitis. METHODS: Sixty-seven teeth affected by adult periodontitis and 7 healthy teeth extracted from patients over 40 years old were used. The teeth were divided into 3 groups according to radiographic data: group 1: five teeth with bone loss less than one-third of the normal alveolar height; group 2: thirty-one teeth with bone loss between one and two thirds; and group 3: thirty-one teeth with bone loss greater than two thirds. The samples were prepared for light and scanning electron microscopy, considering the gingival, middle, and apical thirds in each root. RESULTS: Two control teeth, 4 teeth in group 1, and all teeth in groups 2 and 3 showed resorption areas. Regarding the gingival third, the control teeth did not show any resorption, while 25% of affected teeth in group 1, 38.7% of teeth in group 2, and 35.5% of teeth in group 3 exhibited resorption. Regarding the middle third, 50% of affected teeth belonging to the control group and group 1; 67.7% of teeth in group 2; and 87.1% of teeth in group 3 showed resorption. Regarding the apical third, all teeth belonging to the control group and group 1 showed resorption, while 93.5% and 87.1% of teeth in groups 2 and 3, respectively, exhibited resorption. Most of the resorptions did not extend beyond the cementum. However, in 29.0% of teeth in group 2 and 38.7% of teeth in group 3, resorption had spread as far as the dentin. All the lesions in the control group and group 1 were practically repaired, while only 71.0% of teeth in group 2 and 61.3% of teeth in group 3 showed some sign of reparation. However, in groups 2 and 3, practically all lesions affecting dentin were repaired. CONCLUSIONS: These data suggest that the spread of root resorption is associated with inflammation. This study also suggests that the capacity for repair of root resorption is diminished with greater severity of periodontitis.