At the current time, a similar infectious origin has not yet been confirmed that leads to Beh�et's disease, but certain strains of " Streptococcus sanguinis " has been found to have a homologous antigenicity.
22.
"Since 1997, studies of influenza A ( H5N1 ) indicate that these viruses continue to evolve, with changes in antigenicity and internal gene constellations; an expanded host range in avian species and the ability to infect felids; enhanced pathogenicity in experimentally infected mice and ferrets, in which they cause systemic infections; and increased environmental stability ."
23.
In the past, NIAID supported researchers have improved antigenicity through modifications to the envelope protein, elucidated the envelope structure of HIV, advanced our understanding of the role of cellular responses in controlling HIV, developed improved assays for measuring cytotoxic T lymphocytes ( CTLs ), developed new and better animal models for testing candidate vaccines, and evaluated promising candidates in animal and clinical studies.
