Artificial lymph nodes successfully implanted into mice.

A team from the RIKEN institute in Japan has successfully transplated artifical lymph nodes using a collagen created bioscaffold into mice, where the lymph nodes successfully attracted lymphocytes already circulating in the mouse, and organized them just as they are in normal lymph nodes.  After the node was filled with antigen specific lymphocytes, the team then transplated it to a mouse with no functioning immune system, where the lymphocytes then spread from the artifical node to the mouses own lymph nodes. When injected with the specific antigen, the mouses transplanted immune system responded, producing lymphocytes to neutralize the antigen.

 

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Making memories that last a lifetime

Neurobiologists have discovered a mechanism by which the constantly changing brain retains memories�from that dog bite to that first kiss. They have found that the brain co-opts the same machinery by which cells stably alter their genes to specialize during embryonic development.

 

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How common viruses can turn cells cancerous

Common viruses may play a bigger role in cancer than anyone thought.

 

It is well known that certain viruses can trigger specific cancers. Human papillomavirus, for example, causes around 93 per cent of cancers of the cervix. Now Dominik Duelli and Yuri Lazebnik at Cold Spring Harbor Laboratory in New York and colleagues have found evidence for how they might do it.

 

During tumour development, the chromosomes of affected cells often become wildly rearranged, but no one knew why. Duelli and Lazebnik suspected that cell fusion - when two or more cells unite by merging membranes - might be to blame. Several common viruses can initiate this process.

 

To test their idea, the researchers took human fibroblast cells with genes that made them more likely to turn into a tumour and infected them with a retrovirus that can cause fusion. Sure enough, fused cells had many more chromosomal abnormalities than unfused ones, and when transplanted into mice, only the fused cells produced tumours (Current Biology, DOI: 10.1016/j.cub.2007.01.049).

 

The team is now asking other cancer researchers to examine tumour samples for signs of cell fusion.

 

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