Agent Of Proliferative Kidney Disease Research Articles

Monoclonal antibody and lectin probes recognize developmental and sporogonic stages of PKX, the causative agent of proliferative kidney disease in European and North American salmonid fish

Monoclonal antibody and lectin probes recognize developmental and sporogonic stages of PKX, the causative agent of proliferative kidney disease in European and North American salmonid fish

Development of monoclonal antibodies to PK‘X’, the causative agent of proliferative kidney disease

Abstract. Two monoclonal antibody probes were produced against PK'X’ cells. The parasites were partially purified by filtration and centrifugation of kidney tissue from rainbow trout with proliferative kidney disease and used as antigen for immunization of mice. The resulting monoclonal antibodies reacted with PK'X’ cell antigens in enzyme‐linked immunosorbent assay and immunohistochemistry tests. One antibody (Mab 12) appeared to be specific for PK'X’in kidney tissue, while the other (Mab 18) cross‐reacted with host cell antigens in the kidney tubules. These probes are invaluable tools for the investigation of parasite surface antigens and life cycle studies.

Transmission of PKX. the causative agent of pro-liferative kidney disease (PKD), to rainbow trout Oncorhynchus mykiss following filtration of water and sediments

Transmission of PKX. the causative agent of pro-liferative kidney disease (PKD), to rainbow trout Oncorhynchus mykiss following filtration of water and sediments

Experimental transmission of PKX, the causative agent of proliferative kidney disease, to three species of Pacific salmon

Summary PKX, the causative agent of proliferative kidney disease, was experimentally transmitted to three species of Pacific salmon. Chinook (Oncorbynchus tshawytscba), kokanee (O. nerka) and coho (O. kisutch) salmon were infected by inuaperitoneal injections with PKX and the progress of the disease was examined among fish held in 16–17°C well water. At 42 d post-injection, numerous PKX were found in the kidney interstitium of both chinook and kokanee salmon. No PKX were observed in coho salmon at this time. By 67 d, PKX were found in both interstitial and intraluminal locations in all three species of salmon. At 101 d, PKX were present in the kidney interstitia of chinook and kokanee, but not in coho salmon. Renal inflammation caused a 69% and a 70% reduction in the number of tubules among the chinook and kokanee salmon, respectively, while the coho salmon demonstrated less inflammation with a 35 % reduction in tubule number. The number of interstitial forms of the parasite was greatest in the kokanee salmon, and the intraluminal sporogonic stages were most prevalent in the coho salmon. These observations indicate that these three species of Pacific salmon are susceptible to PKX, although development of the parasite and seventy of disease may vary with host species. Résumé Transmission expérimentale de PKX, l'agent pathogège de la maladie proliférative du rein, Sur trois expèces de saumon Pacifique PKX, l'agent pathogène de la maladie rolifirative du rein, a été transmis sà trois expèces de saumon Pacifique. Les expèces chinook (Oncorbynchus tshawytscha), sockeye (O. nerka) et coho (0. kisutcb) ont été infectées par injection intrapéritoneale de PKX et les progres de la maladie ont été examinès chez des poissons élevés dans de l'eau de puits sà 16–17°C. 42 jours après l'injection, de nombreux PXK ont été trouvés dans l'intersritium rénal des saumons chinook et sockeye, aucun PKX n'a été trouvé dans le saumon coho sà ce momentlh. Après 67 jours, le PKX itait présent sà la fois dans les régions interstitielles et les régions intraluminales des trois espéces de saumon. Aprés 101 jours, le PKX était présent dans I'interstitium rénal des saumon chinook et sockeye, mais pas dans le saumon coho. L'inflammation rénale provoquait une riduction de 69% et 70% du nombre de tubules chez le saumon chinook et chez le saumon sockeye respectivement. Le saumon coho montrait moins d'inflammation avec une réduction de nombre du tubules de 35%. Le nombre de formes interstitielles du parasite était plus grand chez le saumon sockeye et les stades intraluminales sporogenes dominaient chez le saumon coho. Ces observations indiquent que ces trois espèces de saumon Pacifique sont suscetibles au PKX, bien que le développement du parasite et la sévérité de la maladie peuvent varier avec l'espèce de l'hôte. Zusammenfassung Experinaentelle übertragung von PKX, dem auslösenden Erreger der Proliferativen Nierenerkrankung, auf drei Arten des pazifschen Laches PKX, der Erreger der Proliferativen Nierenerkrankun (PKD) wurde experimentell auf drei Arten von pazifischen Lachsen übertragen. Chinook (Oncorbynchus tsbawytscha), Kokanee (O. nerka) und Coho (O. kisutcb) Lachse wurden intraperitoneal mit PKX infiziert. Die Krankheitsentwicklung wurde bei den in 16–17°C warmem Brunnenwasser gehätenen Fischen beobachtet. 42 Tage nach der Injektion wurden bei Chinook und Kokanee zahlreiche PKX irn InterstiriaIraurn der Niere nachgewiesen. Beim Coho traten sie zu dieser Zeit noch nicht auf. Nach 67 Tagen wurden sie bei allen drei Arten sowohl im InterstiriaIraurn als auch in den Lumina gefunden. Nach 101 Taen wurden PKX in den Niereninterstitien von Chinook und Kokanee, nicht aber vom Coho gefunfen. Nierenentzundung verursachte bei Chinook und Kokanee eine 69 bzw. 70%ige Verringerung der Tubuluszahl, während beim Coho die Tubuluszahl nur urn 35% verringert war. Die Anzahl der Interstitialformen des Parasiten war beim Kokanee am größgten. Die intraluminden sporogenen Stadien traten beim Coho am häufigsten auf. Diese Befunde deuten an, daß alle drei Arten von pazifischen Lachsen anfällig gegenüber PKX sind, obwohl bei Parasitenentwicklung und Pathogenität wirtsspezifische Unterschiede bestehen.

Ultrastructural aspects of PKX, the causative agent of proliferative kidney disease in rainbow trout, Salmo gairdneri Richardson

Ultrastructural aspects of PKX, the causative agent of proliferative kidney disease in rainbow trout, <i>Salmo gairdneri</i> Richardson

PKX, the causative agent of proliferative kidney disease (PKD) in Pacific salmonid fishes and its affinities with the Myxozoa.

Proliferative kidney disease (PKD), caused by an unclassified protozoan (PKX), is reported from Pacific salmon, Oncorhynchus tshawytscha (Walbaum) and O. kisutch (Walbaum), and steelhead trout, Salmo gairdneri Richardson, held at the Mad River Hatchery in California, USA. The cumulative mortality attributed to the disease was 95, 13, and 18% respectively. The mortalities were greatest at mean water temperatures of 12-14 degrees C during July 1983. The ultrastructure of the PKX organism and its associated pathology during clinical disease in all three species were consistent with those of the parasite in rainbow trout (Salmo gairdneri) as described in European outbreaks. Significant mortalities did not occur after August, at which time the parasite could no longer be detected in the salmon species. The steelhead continued to exhibit parasites in the kidney interstitium and epithelium and lumens of the tubules. Myxosporidan trophozoites and developing spores were also observed in the lumens of the kidney tubules of these fish. Although a mixed infection with another parasite may have occurred, evidence suggests that the myxosporidans are later stages of PKX. They were only observed in fish exposed to water with the infective stage and were particularly prominent in recovering fish. The PKX organism is similar to UBO, an unclassified protozoan of carp suspected to be an early stage of Sphaerospora renicola Dykovà & Lom. Both parasites infect the blood and kidney, divide by endogeny, and are released by disintegration of the primary mother cell. The intraluminal myxosporean forms show similarities to Sphaerospora spp. in that they are monosporous and sporoblasts are formed within pseudoplasmodia.(ABSTRACT TRUNCATED AT 250 WORDS)

Ultrastructure of a Haplosporean‐like organism: the possible causative agent of proliferative kidney disease in rainbow trout

The protozoan parasite which has been suggested as the causative agent of proliferative kidney disease in rainbow trout has previously been described as an‘amoeba’. However, this ultra‐structural study of the organism (named‘PKX’) has demonstrated many similarities to a group of invertebrate parasites, the genus Marleilia (currently classified in the Haplosporea). The suggested affinity of PKX‘ to Marteilia is based on the presence of internal cleavage,‘haplosporosomes’, and an amorphous cell wall. Other cytoplasmic inclusions also show characteristics of the genus. Since a spore stage has not been recognised in ‘PKX’, a definitive taxonomic statement cannot yet be made.