Background

In vitro methods of evaluating or recapitulating developmental toxicity have existed for several decades.  Only relatively recently, however, has a concerted effort been made to apply some of these methods in a predictive capacity. Because there is never a perfect correlation between development in vivo and a truncated in vitro model, there will always be some uncertainty in the application of these models. As each group uses an alternative model, it learns about the performance characteristics of that model, and how to improve it.  This workshop will convene users of several models of developmental toxicity (embryonic stem cells, whole embryo culture, zebrafish) to share their experiences so that we can all shorten our learning curves and hasten the optimal application of these assays in a predictive capacity.

Workshop Goals

Sponsored by the HESI Developmental and Reproductive Toxicology (DART) Technical Committee, with a workshop Steering Team comprised of scientists from government, academia, and industry, the objective of this workshop was to share lessons learned, to share best and worst applications, and to identify strategies for addressing shortcomings in subsequent collaborations (i.e., best ways forward).

Posters

As a venue to share information on approaches and successes, this workshop utilized posters to address the use of each model system to predict in vivo mammalian developmental toxicity or explore mechanisms of toxicity.  One of the primary outcomes from this workshop was the collaborations between labs as a means to move the field forward.

Workshop Format

The workshop was conducted over two days.  The first morning consisted of a plenary session, with introductory presentations on each of the assays, and an overview talk on constructing predictive statistical models.  The first afternoon consisted of break-out sessions, with targeted presentation and time included for discussion of the posters relevant to the specific assay.  There will be a reception on the evening of the first day which provided an opportunity for interaction among the break-out groups and discussion of the posters collectively.  The second morning consisted of break-out groups, with additional presentations and round-table discussion.  The final afternoon was for reports from the break-out groups, with panel discussion and cross-group consensus building.

Break-out Sessions

Break-out sessions addressed each of the three assays being considered:  stem cells, whole embryo culture, and zebrafish.  Some questions to be debated include the following:

• Is there a consensus about what the best/appropriate methods are for using this model as a predictive toxicity test?  If so, what are they?  If not, what needs to be done to move things towards a consensus?  How can this be assisted by this meeting?
• Is there a consensus “best method” for constructing and running a test for predicting the toxicity of environmental exposures?  For pharmaceutical compounds?
• About developing new predictive methods: Are improvements necessary?  If so, what kind of new methods are being evaluated? Are there additional methods which the workshop group identified as being worth following-up?
• Are there consensus outcomes that can be generally applied?

To access a copy of the workshop agenda, click here.