Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain
the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in
Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles
and JavaScript.
Preclinical challenge studies of AIDS vaccines in non-human primates have an important role in the AIDS vaccine development effort. However, to be most useful, challenge models need to be improved to more closely reflect the actual biological circumstances of HIV-1 infection and transmission in humans.
The finding that fetal mouse neural stem cells do not differentiate into hematopoietic cells contradicts findings from earlier reports and adds to the controversy regarding the rigor of the experimental methods used to demonstrate the differentiation repertoire of stem cells. (pages 268–273)
The finding that cloned mice, produced by transfer of nuclei from cumulus cells, develop obesity but do not transmit the phenotype to their offspring provides further evidence that cloned embryos are vulnerable to epigenetic change. (pages 262–267)
The development of anticancer therapies that target apoptosis pathways may be hampered by resistance of certain tumor cells to death signals. New findings show that tumor cells lacking the pro-apoptotic protein Bax are resistant to apoptosis induced by the death ligand TRAIL, but that chemotherapeutic drugs can restore their sensitivity to TRAIL. (pages 274–281)
The leucine-rich repeat-containing gene, LGI1, was identified as a possible tumor suppressor gene involved in brain tumor development. It now appears that it also plays a role in abnormal brain development that leads to epilepsy.
Interactions between recipient T cells and donor endothelial graft cells may be an important mechanism for both acute and chronic rejection of vascularized allografts. This finding provides a starting point for investigations to develop novel ways of inducing long-lasting immunologic tolerance to donor antigens. (pages 233–239)
