Synovial fluid studies in navicular disease

The purpose of this study was to investigate biochemical changes in synovial fluid in navicular disease, and to establish if synovial fluid from the distal interphalangeal joint (DIP) could be used diagnostically to assess alterations in the synovial fluid of the navicular bursa. Cartilage oligomeric matrix protein (COMP), total glycosaminoglycans (GAG), hyaluronan (HA), metalloproteinases 2 and -9 (MMP-2 and MMP-9) and total protein (TP) levels were determined in synovial fluids obtained from 18 navicular bursae and 35 DIP -joints from animals suffering from navicular disease, and the same synovial structures in 16 joints of horses with no evidence of abnormalities involving the foot. To avoid dilution effects, GAG/COMP, HA/COMP, MMP-2/ COMP and MMP-9/COMP ratios were also calculated for different synovial cavities. There was a good correlation, for COMP, GAG, HA, MMP-2 and TP levels, between synovial fluid from the navicular bursa and fluid from the DIP -joint in healthy animals. However, in animals with navicular disease, only COMP levels showed no difference between the navicular bursal fluid and the DIP-joint fluid concentration. Thus, enabling the use of COMP to standardise other biochemical concentration measurements from the synovial joint fluids. In horses with navicular disease, there was a significantly lower absolute concentration of GAG, and a significantly lower GAG/COMP ratio, in the synovial fluid of the navicular bursa and the DIP-joint compared to synovial fluid from the same joints from healthy horses. In contrast, the absolute HA concentration and HA/ COMP, MMP-2/COMP and MMP-9/COMP ratios were higher in synovial fluid from the DIP-joint of horses with navicular disease, and MMP-2 and MMP-9 relative activity levels and MMP-2/COMP and MMP-9/ COMP ratios were increased in fluid from navicular bursae in horses with navicular disease when compared to a control group.

Inheritance of antibody specificity. II. Anti-(4-hydroxy-5-bromo-3-nitrophenyl) acetyl in the mouse

Mice of 17 inbred strains produced anti-(4-hydroxy-5-bromo-3-nitrophenyl)-acetyl (NBrP) of three different fine specificity types. Anti-NBrP antibodies of all allotype b mice (five strains tested) had a high relative affinity for (4-hydroxy-3.5-dinitrophenyl) acetyl (NNP) but low for (4-hydroxy-5-cloro-3-nitrophenyl) acetyl (NCP). Another category was characterized by high relative affinity for NCP but low for NNP. This category included most of the tested strains. The third category (CBA and C3H strains) had an intermediate fine specificity. Associated with fine specificity characteristics were anti-NBrP titers, mice of allotype b had lower titers than the other mice. Studies of congenic, recombinant inbred, F1 and backcross mice showed that both fine specificity and the magnitude of the anti-NBrP response of tbalb/C MICE WERE CONTROLLED BY AN ALLOTYPE-LINKED GENE. This gene was dominant over the C57BL/6 ALLELE. Lack of recombinant mice in the backcross generatioterns on the other suggest close linkage between the two genes.

Inheritance of antibody specificity. II. Anti-(4-hydroxy-5-bromo-3-nitrophenyl) acetyl in the mouse

Mice of 17 inbred strains produced anti-(4-hydroxy-5-bromo-3-nitrophenyl)-acetyl (NBrP) of three different fine specificity types. Anti-NBrP antibodies of all allotype b mice (five strains tested) had a high relative affinity for (4-hydroxy-3.5-dinitrophenyl) acetyl (NNP) but low for (4-hydroxy-5-cloro-3-nitrophenyl) acetyl (NCP). Another category was characterized by high relative affinity for NCP but low for NNP. This category included most of the tested strains. The third category (CBA and C3H strains) had an intermediate fine specificity. Associated with fine specificity characteristics were anti-NBrP titers, mice of allotype b had lower titers than the other mice. Studies of congenic, recombinant inbred, F1 and backcross mice showed that both fine specificity and the magnitude of the anti-NBrP response of tbalb/C MICE WERE CONTROLLED BY AN ALLOTYPE-LINKED GENE. This gene was dominant over the C57BL/6 ALLELE. Lack of recombinant mice in the backcross generatioterns on the other suggest close linkage between the two genes.