[[File:Influenzastructure.png|thumb|360px|The biosynthesis Structure of proBNP and its derivativesthe influenza virus.<ref name="Arti1">Cardiac biomarker testing in the clinical laboratory: Where do we stand? General overview of the methodology with special emphasis on natriuretic peptidesHost Protective Immune Responses against Influenza A Virus Infection, Aldo ClericoHi Eun Jung, Claudio PassinoHeung Kyu Lee, Maria Franzini, Michele Emdin, June 2014, Clinica Chimica Acta, httphttps://dxwww.doimdpi.orgcom/10.10161999-4915/12/5/504/j.cca.2014.06.003htm</ref>]]