Three-dimensional changes of noses after transplantation of implant-type tissue-engineered cartilage for secondary correction of cleft lip–nose patients

Introduction: We have developed an implant-type tissue-engineered cartilage using a poly-l-lactide scaffold. In a clinical study, it was inserted into subcutaneous areas of nasal dorsum in three patients, to correct cleft lip–nose deformity. The aim of this study was to helping evaluation on the efficacy of the regenerative cartilage. Methods: 3D data of nasal shapes were compared between before and after surgery in computed tomography (CT) images. Morphological and qualitative changes of transplants in the body were also evaluated on MRI, for one year. Results: The 3D data from CT images showed effective augmentation (>2 mm) of nasal dorsum in almost whole length, observed on the medial line of faces. It was maintained by 1 year post-surgery in all patients, while affected curves of nasal dorsum was not detected throughout the observation period. In magnetic resonance imaging (MRI), the images of transplanted cartilage had been observed until 1 year post-surgery. Those images were seemingly not straight when viewed from the longitudinal plain, and may have shown gentle adaptation to the surrounding nasal bones and alar cartilage tissues. Conclusion: Those findings suggested the potential efficacy of this cartilage on improvement of cleft lip–nose deformity. A clinical trial is now being performed for industrialization

Utility of NucleoCounter for the chondrocyte count in the collagenase digest of human native cartilage

In cartilage tissue engineering, viable cell numbers should be correctly counted in the collagenase digest of the biopsied cartilage. However, this is a difficult task due to the presence of matrix debris, cell ghosts and their aggregates. To search for the correct cell counting method in this situation, we evaluated the utility of an automatic cell counting device, the NucleoCounter, and compared it with conventional staining using the LIVE/DEAD® kit. We first measured the cell numbers of a standard chondrocyte sample by the NucleoCounter, which showed a high accuracy (R2 = 0.9999) and reproducibility (%CV: 2.00–8.66). We then calculated the cell numbers and viability in some collagenase digests of native cartilage using either the NucleoCounter or LIVE/DEAD® kit, revealing that the total cell numbers, viable ones and viability were highly correlated between them (R2 = 0.9601, 0.9638 and 0.917, respectively). However, both the intrapersonal and interpersonal variabilities in the NucleoCounter was significantly decreased to about 1/20–1/5, compared to that of the LIVE/DEAD® kit. The NucleoCounter was regarded as a useful tool for simple, rapid, and highly reproducible cell counts, which may not only provide constant experimental data in a certain laboratory, but also contribute to the high reproducibility of the clinical results of cartilage tissue engineering among multiple institutions