Experimental Brucella Abortus Strain 19 Arthritis in Young Cattle

Abstract

Abstract. Several reports have shown an association between lameness in cattle and vaccination with Brucella abortus strain 19. Affected joints are culture negative for Brucella, but the synovial fluid is positive for B. abortus antibodies. The joints contain cloudy fluid, with villous proliferation of the synovium. Brucella abortus antigens are often found in the synovium with fluorescent antibody staining. This report describes the experimental reproduction of a chronic synovitis in 6 young Angus steers using intra-articular injections of B. abortus strain 19. The carpal and tibia1 joints were injected with 5 x 10 9 colony-forming units/ml of B. abortus strain 19 and regularly biopsied over a 28-day period. Steers started becoming serologically positive for B. abortus on postinoculation day (PID) 5 and were all positive by PID 7. Joints were cultured and examined by fluorescent antibody staining, immunohistochemical methods, and light and transmission electron microscopy. Lesions typical of the field cases were present by PID 21. Brucella abortus was cultured more often during PID l-5 (6 of 9 joints) than during PID 7-28 (3 of 15 joints). Brucella abortus was only found on PID 1, and 5 by fluorescent antibody staining and in only 2 joints immunohistochemically on PID 5 and 7. The reproduction of lesions typical of field cases but the inability to locate B. abortus antigens in the synovium raises the question of whether in field cases the synovium is continually or intermittently seeded with bacteria or if factors other than just the bacterium are needed to perpetuate the lesion.During the 1970s an association between lameness in young cattle and a positive serologic test for Brucella abortus was described. 1 The only known exposure of many of these cattle to B. abortus was from B. abortus strain 19 vaccination 9-12 months previously. The condition has now been reported in England, the USA, and Australia. 1,4,12,14,15 The stifle joints are most commonly involved. Affected joints are culture negative for Brucella spp., but synovial fluid is positive for Brucella antibodies. Often, B. abortus antigens are detected in synovium by fluorescent antibody (FA) staining. 1,4,15 Gross lesions in affected joints consist of villus proliferation of the synovium with fibrosis and pitting erosions of the opposing cartilaginous surfaces. The synovial fluid is usually cloudy and turbid but not purulent. Microscopically, lymphoplasmacytic infiltrates and granulomata are present in the subsynoviurn.In 1 of those reports, although Brucella spp. was not isolated from affected joints, B. abortus strain 19 was isolated from the supramammary lymph node of 1 animal.14 Experimental attempts to reproduce the disease by injection of strain 19 organisms have not beenOn postinoculation days (PID) 1, 3, 5, 7, 10, 14, 21, and 28, biopsies

Brucella abortus Invasion of Synoviocytes Inhibits Apoptosis and Induces Bone Resorption through RANKL Expression

“…Importantly, cultures of synovial fluid were negative in these cases, suggesting that the bacterium was located intracellularly in the synovial membrane. In support of this hypothesis, foci of intracytoplasmic granular reactions were detected by immunofluorescence with anti-Brucella antibodies in the synovial surface of joints obtained from cattle experimentally infected with B. abortus S19 (63,64). Interestingly, synoviocytes are located in the intimal layer of the synovium, which agrees with the "synovial surface" location described in that study.…”

Potential Role of Fibroblast-Like Synoviocytes in Joint Damage Induced by Brucella abortus Infection through Production and Induction of Matrix Metalloproteinases

“…Importantly, cultures of synovial fluid were negative in these cases, suggesting that the bacterium was located intracellularly in the synovial membrane. In support of this hypothesis, foci of intracytoplasmic granular reactions were detected by immunofluorescence with anti-Brucella antibodies in the synovial surface of joints obtained from cattle experimentally infected with B. abortus S19 (22,55). Interestingly, FLS are located in the intimal layer of the synovium, which agrees with the "synovial surface" location described in that study.…”

“…In cattle experimentally infected with B. abortus S19, a marked inflammation dominated by neutrophils was observed along the joint surface during the first 3 days postinfection, but this infiltrate evolved to a lymphocytic and histiocytic one by 14 days p.i. (22). In vivo, recruited neutrophils and monocytes may contribute to joint damage in at least two ways.…”

Brucella ceti and Brucellosis in Cetaceans

“…These bone-joint lesions are not uncommon in secondary hosts such as humans brucellosis cases (Chelli-Bouaziz et al, 2008). With the solely example of occasional hygromas in cattle with brucellosis (Humphreys and Moore, 1941), joint lesions are rare in ungulates (Johnson et al, 1994). …”