ATROPHIC RHINITIS AND IMMUNE PROTECTION - COMPILATORY COMMUNICATION

Based on the author's own investigations on atrophic rhinitis (AR) of swine, experiences on the etiology, pathogenesis and epizootiology of the disease have been summarized. It has been stressed that - accordin g to the two etiologic agents - two phases follow each other in the pa thogenesis of the disease. First Bordetella bronchiseptica (Bb) strain s colonize in the nose and their dermonecrotoxin (DNT) causes a severe inflammation in the mucosa causing the separation of cilia and epithe lial cells. That is followed some weeks later by colonization of DNT p roducing Pasteurella multocida (Pm) strains belonging to the D serotyp e which is - due to the biological characteristics of Pm - is not poss ible in reverse order. Pm-DNT due to the lysis and later on resorption of osteocytes and osteoclasts of nasal bones causes severe regressive processes and later on degeneration first in the turbinated bones and also in other nasal bones. The latter process can also develop due to a Pm infection in several months old pigs. In toxin model experiments , the author has clarified that due to Bb- and Pm-DNTs regressive alte rations develop not only in the nose but also in the stomach, liver, s pleen, kidneys and lymph nodes which become more severe due to the eff ect of Bb-DNT. In case of the ulterior, number of T and B cells of per ipheral blood decreases significantly. Thus, AR is a disease affecting the entire organism in which damage of the immune system is stressed. Due to the result of an immunization with toroid prepared from Pm-DNT , large amounts of neutralizing antibodies appear in the blood (4.66 n eutralization index, NI) and manifold amounts of that in the nasal exc rete (30.00 NI). IgG type neutralizing antibodies produced in the nasa l mucosa play the most important role in the immune protection against Pm. The knowledge of that created the possibility of the most effecti ve immune protection against AR, the control based on a subunit vaccin e. In the next future, a vaccine will be in developing, that consists of 3 Bb strains, of one Pm strain of A serotype and of a toroid of a p urified DNT of Pm. This vaccine protects the sows and their offsprings by a single immunization against AR.