If you have been keeping up with the news for the past eight months or so, you will be aware that the issue of bioterrorism has received a lot of coverage. Smallpox was eradicated in 1977, and only two declared stocks of variola virus — the causative agent of smallpox — exist. But, is it possible that undeclared virus stocks exist, and could they be used as biological weapons? Is the world prepared for such an eventuality? These issues are discussed by Geoffrey Smith and Grant McFadden on page 521.

Three articles in this issue focus on aspects of autoimmune disease. Immunologists now have a fairly good understanding of the central and peripheral mechanisms that prevent autoimmune responses. On page 487, Stephen Anderton and David Wraith discuss a phenomenon that is less well understood — how the biochemical tuning of T-cell functional avidity shapes the T-cell repertoire in a way that minimizes the potential for autoimmune responses. On page 465, Fabienne Mackay and Jeffrey Browning discuss BAFF, a recently discovered survival factor for B cells that could be a new therapeutic target for antibody-mediated autoimmune diseases. The third article on autoimmunity is an Opinion piece by Richard Pope on page 527, in which he suggests that it might be possible to influence the survival of pathogenic cells in rheumatoid arthritis by targeting apoptotic pathways.

Schistosomiasis is a disease that is caused by parasitic worms, in which individuals can become chronically infected despite a robust immune response. On page 499, Edward Pearce and Andrew MacDonald outline the immunobiology of this disease.

Finally, two articles concern T-cell signalling — on page 476, Martin Turner and Daniel Billadeu discuss VAV proteins, and on page 512, Ton Schumacher descibes T-cell-receptor gene therapy.