The paper
D.L. Mallery et al., “Antibodies mediate intracellular immunity through tripartite motif-containing 21 (TRIM21),” PNAS, 107:19985-90, 2010. Free F1000 Evaluation
The finding
Antibodies work by activating the complement cascade, preventing invading microorganisms from entering cells, or binding to a pathogen and marking it for destruction by immune cells. Now, Leo James and colleagues at the MRC-LMB in Cambridge have discovered a fourth method that works inside cells, providing a “last line of defense” against infection.
The ambush
James’ lab observed that antibodies can remain bound to adenovirus as it infects cells. The result sparked their curiosity, because they had previously shown that the intracellular protein TRIM21 binds to the Fc region of antibodies with higher affinity than any other antibody receptor in the body.
Animated Immunity
The neutralization
They found that TRIM21 adds ubiquitin to the adenovirus-antibody complex, targeting it for destruction by the proteasome. The finding “adds conceptually ...
