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BACKGROUND: In vitro studies using nucleus pulposus (NP) cells are commonly used to investigate disc cell biology and pathogenesis, or to aid in the development of new therapies. However, lab-to-lab variability jeopardizes the much-needed progress in the field. Here, an international group of spine scientists collaborated to standardize extraction and expansion techniques for NP cells to reduce variability, improve comparability between labs and improve utilization of funding and resources. METHODS: The most commonly applied methods for NP cell extraction, expansion, and re-differentiation were identified using a questionnaire to research groups worldwide. NP cell extraction methods from rat, rabbit, pig, dog, cow, and human NP tissue were experimentally assessed. Expansion and re-differentiation media and techniques were also investigated. RESULTS: Recommended protocols are provided for extraction, expansion, and re-differentiation of NP cells from common species utilized for NP cell culture. CONCLUSIONS: This international, multilab and multispecies study identified cell extraction methods for greater cell yield and fewer gene expression changes by applying species-specific pronase usage, 60-100 U/ml collagenase for shorter durations. Recommendations for NP cell expansion, passage number, and many factors driving successful cell culture in different species are also addressed to support harmonization, rigor, and cross-lab comparisons on NP cells worldwide.

peer-reviewed Ireland has a strong tradition of philanthropy, and charity has played a significant part in the development of modern Ireland. Charitable giving in Ireland has, however, changed considerably over the past 15 years. This paper analyses charitable giving in Ireland by using the general population of the Mid-West region of Ireland as a sample of the entire Irish population. A self-completion questionnaire is used to examine people’s altruistic behaviour, in order to determine whether the recent economic downturn has had an impact on their attitudes towards charity. This paper concludes that financial stability is not the sole determinant of an individual’s ability to make donations to charity. Irish philanthropy is very reactive and spontaneous in nature; therefore the level of donations is unlikely to fluctuate greatly between periods of both strong and weak economic activity.