Coccidiosis vaccine
AssigneeMerck & Co., Inc.
InventorsPeter K. Murray, Stefan Galuska
Life of this patent
Estimating the term…
Abstract
Sporozoites of coccidia fail to develop in chickens which are immune and many are blocked from penetrating host cells. Although previous attempts to immunize chickens with non-viable coccidial antigens have been unsuccessful it has been discovered that extracts from sporozoites or sporulated oocysts of E. tennella induce high levels of protective immunity. These extracts contain at least 15 polypeptides many of which are associated with the surface of the sporozoite and induce good immune responses. Antibody to these polypeptides blocks sporozoite-host cell penetration in vitro and neutralizes sporozoites in vivo. One or more of these polypeptides may be used as an antigen to protect against coccidiosis.
Claims13
An extract obtained by grinding and centrifuging a suspension of sporulated oocysts of Eimeria tenella, and purifying sporozoites from the pelleted material resulting from the centrifugation step, the pelleted material containing antigens capable of immunizing chickens against coccidiosis.
An extract from the supernatant liquid obtained by centrifuging a suspension of ground sporulated oocysts of Eimeria tenella, the extract containing polypeptides having molecular weights of 235, 105, 94, 71, 64, 45 and 26 KD.
Dependencies are inferred from the claim text.