The Up-Scale Manufacture of Chondrocytes for Allogeneic Cartilage Therapies

Background: Allogeneic chondrocyte therapies need to be developed to allow more individuals to be treated with a cell therapy for cartilage repair and to reduce the burden and cost of current two-stage autologous procedures. Up-scale manufacture of chondrocytes using a bioreactor could help provide an off-the-shelf allogeneic chondrocyte therapy with many doses being produced in a single manufacturing run. Here we assess a Good Manufacturing Practice compliant hollow-fibre bioreactor (Quantum®) for adult chondrocyte manufacture. Methods: Chondrocytes were isolated from knee arthroplasty derived cartilage (n=5) and expanded in media supplemented with 10% fetal bovine serum (FBS) or 5% human platelet lysate (hPL) on tissue culture plastic (TCP) for a single passage. hPL supplemented cultures were then expanded in the Quantum® bioreactor for a further passage. Matched, parallel cultures in hPL or FBS were maintained on TCP. Chondrocytes from all culture conditions were characterised in terms of growth kinetics, morphology, immunoprofile, chondrogenic potential (chondrocyte pellet assays) and single telomere length analysis. Results: Quantum® expansion of chondrocytes resulted in 86.4±38.5x106 cells in 8.4±1.5 days, following seeding of 10.2±3.6 x106 cells. This related to 3.0±1.0 population doublings in the Quantum® bioreactor, compared with 2.1±0.6 and 1.3±1.0 on TCP in hPL and FBS supplemented media, respectively. Quantum® and TCP expanded cultures retained equivalent chondropotency and mesenchymal stromal cell markers immunoprofiles, with only integrin marker, CD49a, decreasing following Quantum® expansion. Quantum® expanded chondrocytes demonstrated equivalent chondrogenic potential (as assessed by ability to form and maintain chondrogenic pellets) with matched hPL TCP populations. hPL manufacture however, led to reduced chondrogenic potential and increased cell surface positivity of integrins CD49b, CD49c and CD51/61 compared with FBS cultures. Quantum® expansion of chondrocytes did not result in shortened 17p telomere length when compared with matched TCP cultures. Discussion: This study demonstrates that large numbers of adult chondrocytes can be manufactured in the Quantum® hollow-fibre bioreactor. This rapid, up-scale expansion, does not alter chondrocyte phenotype when compared with matched TCP expansion. Therefore, the Quantum® provides an attractive method of manufacturing chondrocytes for clinical use. Media supplementation with hPL for chondrocyte expansion may, however, be unfavourable in terms of retaining chondrogenic capacity

No correlation exists Between Tibial And Femoral Based Measurements Of Patella Alta In A Population with chronic patellofemoral pain or instability undergoing patella distalisation

Purpose To investigate if Patellotrochlear index (PTI) predicts patella alta as determined by tibial based methods of Insall Salvati (IS) and Caton Deschamp (CD) in a pathological population (with patellofemoral pain and/or instability). In addition to determining if PTI and Sagittal Patellofemoral engagement (SPE) correlate with trochlea length as determined by Lateral condyle index (LCI). Methods Patients with confirmed patella alta (IS/CD ratio > 1.2) undergoing tibial tubercle osteotomy for patellofemoral pain/instability with an available MRI were included. Patients who had undergone previous soft tissue realignment, prior surgery or trauma to the extensor mechanism were excluded. Two raters measured the IS, CD, PTI, SPE, LCI and Knee flexion angle (KFA) on MRI. Inter-observer reliability and correlation between measurements were calculated. Results 71 knees were included. PTI(0.73), SPE(0.836), LCI(0.701), KFA(0.8) demonstrated good to near excellent inter-observer reliability. IS(0.65) and CD(0.66) demonstrated moderate inter-observer reliability. PTI and SPE showed the strongest significant correlation (0.8112, p = 2.2x10-16). IS and CD (0.39, p = 0.0007) showed a moderate significant correlation. PTI and KFA (0.53, p = 1.685x10-6), SPE and KFA (0.61, p = 1.991x10-8) had a significant moderate correlation. LCI and KFA (-0.37, p = 0.0017), showed a significant moderate negative correlation. All other measurement indices correlated poorly and were insignificant. A total of 94.4% of the knees were defined as having patella alta using IS with the remaining 5.6% having a raised CDI. Only 14% of cases had an IS of >1.2, a CDI >1.2 and a PTI <0.125, which increased to 39% (28/71) when the threshold for PTI was increased to <0.28. Conclusion There was no correlation between tibial (IS and CD) and femoral methods (PTI and SPE) of quantifying patella alta. PTI and SPE did not correlate with trochlea length as measured by LCI. PTI, SPE and LCI are significantly affected by the KFA during MRI Level of Evidence level IV, retrospective diagnostic radiographic investigatio

EVALUATING THE UTILITY OF SPECT/CT FOR THE IDENTIFICATION OF CARTILAGE LESIONS: A SYSTEMATIC REVIEW

AbstractObjectiveA common orthopaedic pain found in a wide spectrum of individuals, from young and active to the elderly is anterior knee pain (AKP). It is a multifactorial disorder which is thought to occur through muscular imbalance, overuse, trauma, and structural malalignment. Over time, this can result in cartilage damage and subsequent chondral lesions. Whilst the current gold standard for chondral lesion detection is MRI, it is not a highly sensitive tool, with around 20% of lesions thought to be mis-diagnosed by MRI. Single-photon emission computerised tomography with conventional computer tomography (SPECT/CT) is an emerging technology, which may hold clinical value for the detection of chondral lesions. SPECT/CT may provide valuable diagnostic information for AKP patients who demonstrate absence of structural change on other imaging modalities. This review systematically assessed the value of SPECT/CT as an imaging modality for knee pain, and its ability to diagnose chondral lesions for patients who present with knee pain.MethodsUsing PRISMA guidelines, a systematic search was carried out in PubMed, Science Direct, and Web of Knowledge, CINAHL, AMED, Ovid Emcare and Embase. Inclusion criteria consisted of any English language article focusing on the diagnostic value of SPECT/CT for knee chondral lesions and knee pain. Furthermore, animal or cadaver studies, comparator technique other than SPECT/CT or patients with a pathology other than knee chondral lesions were excluded from the study. Relevant articles underwent QUADAS-2 bias assessment.Results11,982 manuscripts were identified, and the titles were screened for relevance. Seven studies were selected as being appropriate and were subjected to QUADAS-2 assessment. All 7 articles scored low for bias. Two papers deemed that the ICRS score of chondral lesions at intraoperative assessment correlated with SPECT/CT tracer uptake. Two studies concluded that MRI significantly correlated with SPECT/CT tracer uptake, with some instances whereby SPECT/CT identified more chondral lesions than MRI. Two papers compared bone scintigraphy (BS) to SPECT/CT and concluded that SPECT/CT was not only able to identify more chondral lesions than BS, but also localise and characterise the lesions.ConclusionEvidence implies that SPECT/CT may be a useful imaging modality for the detection and localisation of cartilage lesions, particularly in discrepant cases whereby there is an absence of lesions on other imaging modalities, or a lack of correspondence with patients’ symptoms. More studies would be of value to confirm the conclusions of this review.Declaration of Interest(b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project