Area: Virology Flow cytometry: chicken T cell-mediated immune responses after Newcastle disease virus vaccination A recent study in the Journal Vaccine has found the application of Flow Cytometry (FACS) to be useful in order to study chicken T cell biology. Following vaccination against Newcastle disease T-cell markers were compared using fluorescently labelled antibodies. These antibodies are available on antibodies-online: CD8b, CD4, CD3, CD8a, TCRgd, CD45 and CD44. Newcastle disease affects many domestic and wild avian species. Domestic poultry is highly susceptibility to the contagious disease and occasionally has severe impact on the poultry industries. Exposure of humans to infected birds can cause mild conjunctivitis and influenza-like symptoms, but is otherwise no hazard to human health. The current study establishes Flow Cytometry (FACS) as a useful and quick method for the diagnosis of chicken samples.