MBL2 and infection: The classical pathway is triggered by a ‘lethal array’ of antibody on a target surface, the lectin pathway is initiated when a lectin such as mannan-binding lectin (MBL) binds a pathogen, and the alternative pathway constantly ‘ticks over’ in fluids, priming the system to enable rapid response in the face of infection; this background turnover of complement results in continual surveillance of tissues and preservation of health; there are many excellent reviews in this area [1–4].