The alpha 1-proteinase inhibitors of trypsin, Spi1, Spi3A, and Spi3B, in bronchoalveolar lavage fluid (BALF) and serum of horses were separated by electrophoresis, and their proportions were quantified in 12 control horses and 12 with chronic obstructive pulmonary disease (COPD). A significantly lower proportion of Spi3B (P < 0.05) and higher proportion of Spi1 (P < 0.02 to P < 0.01) were detected in BALF, compared with serum, in control and COPD-affected horses and appeared to be attributable to reduced Spi3 activity in BALF. There was no significant difference between the control and COPD groups in this respect, indicating that the decrease in Spi3 may be a physiologic phenomenon. The differences observed may be associated with proteolytic damage to or preferential complex formation by Spi3.

The alpha 1-proteinase inhibitors of trypsin, Spi1, Spi3A, and Spi3B, in bronchoalveolar lavage fluid (BALF) and serum of horses were separated by electrophoresis, and their proportions were quantified in 12 control horses and 12 with chronic obstructive pulmonary disease (COPD). A significantly lower proportion of Spi3B (P < 0.05) and higher proportion of Spi1 (P < 0.02 to P < 0.01) were detected in BALF, compared with serum, in control and COPD-affected horses and appeared to be attributable to reduced Spi3 activity in BALF. There was no significant difference between the control and COPD groups in this respect, indicating that the decrease in Spi3 may be a physiologic phenomenon. The differences observed may be associated with proteolytic damage to or preferential complex formation by Spi3.

Turkey enteric coronavirus (TCV) from intestinal contents of diarrheal poults was isolated and serially propagated in HRT-18 cells, an established cell line derived from a human rectal adenocarcinoma. In these cells, TCV induced cytopathic changes, including polykaryocytosis, which depended on trypsin in the medium and incubation at 41 C. Viral antigens could be demonstrated in the cytoplasm by immunofluorescence, and extracellular virus was detected by an ELISA and negative electron microscopy. The cell-free virus had characteristics of TCV: shape, surface projections, buoyant density of 1.18 to 1.20 g/ml in sucrose, and hemagglutination of rat RBC. The one-step growth curve was complete by postinoculation hours 14 to 16, and maximal titers reached 9 to 9.5 log10 TCID50/ml during 5 passages, after which the titer remained stable. Electron microscopic examination of infected cell monolayers revealed budding of typical coronavirus particles through intracytoplasmic membranes and accumulation of complete virus in cytoplasmic vesicles. Late in the infection, aggregated progeny vial particles were detected near the outer surface of infected cells. One-day-old turkey poults inoculated orally with tissue culture-adapted TCV isolates developed mild to severe diarrhea.

The ability of Mycoplasma hyopneumoniae to agglutinate RBC was evaluated to develop an in vitro cytadsorption assay. Using swine RBC in a microtitration hemagglutination test, no agglutination or partial agglutination was detected. Comparison of RBC from various other species indicated that improved hemagglutination was obtained with RBC from turkeys. This hemagglutination was detected only when mycoplasma cells used in the assay had been frozen and thawed, heated at 50 C for 30 minutes, or treated with trypsin. Treatment of RBC with trypsin or neuraminidase enhanced hemagglutination. Possible surface lectin activity in M hyopneumoniae was evaluated by use of carbohydrates in a blocking assay; hemagglutination was not inhibited by any of 13 carbohydrates evaluated. Mycoplasma hyopneumoniae convalescent porcine serum and monoclonal antibodies against 2 M hyopneumoniae immunogens of molecular weights of 64,000 and 41,000 inhibited hemagglutination.

Ovulation has been likened to an inflammatory process. Inflammatory cells accumulate in the ovulating follicle, presumably because of chemotactic factors. Chemotactic activity was measured in fluid aspirated from follicles of estrous mares 0, 12, 24, and 36 hours after ultrasonographic detection of a 35-mm follicle and IV treatment with 2,500 IU of human chorionic gonadotropin. Chemotaxis was assessed by measuring directional migration of equine neutrophils under agarose. Follicular fluid acted as a chemoattractant for neutrophils, but there was no significant difference in chemotactic activity among different time intervals after administration of human chorionic gonadotropin. On the basis of results of various treatments, chemotactic properties of serum and follicular fluid were similar. Chemotactic activity was significantly reduced by heating (56 C for 30 minutes) and by trypsinization and was virtually removed by charcoal treatment. Dialyzing the follicular fluid (3,500 and 8,000 molecular weight cut-off) significantly reduced the chemotactic activity of follicular fluid and serum. The importance of chemotactic factors in the process of ovulation in the mare is yet to be established.

Serum trypsinogen concentration was studied in 6 adult mixed-breed dogs randomly fed diets containing 6.8, 31.4, or 39.7% protein (dry weight) for 3 weeks each. Blood was collected on days 20, 21, and 22 of each feeding period, and serum trypsinogen concentrations were determined by radioimmunoassay of trypsin-like immunoreactivity (TLI). Mean serum TLI concentrations for each dog fed each diet were compared. A significant (P < 0.05) positive linear relationship (P < 0.02) was determined between serum TLI concentrations and the percentage of dietary protein. Mean serum TLI concentrations for each dog fed all diets ranged from 5.7 to 20.2 microgram/L.

OBJECTIVE To use proteomic analysis to determine the protein constituents of synovial fluid samples from the stifle joints of dogs with and without osteoarthritis secondary to cranial cruciate ligament rupture (CCLR). ANIMALS 12 dogs with clinically normal stifle joints (controls) and 16 dogs with osteoarthritis secondary to CCLR. PROCEDURES A synovial fluid sample was obtained from all dogs. Synovial fluid total protein concentration was determined by the Bradford assay. Proteins were separated by use of a 1-D SDS-PAGE to detect protein bands that differed between dogs with and without osteoarthritis. Those protein bands then underwent trypsin digestion and were analyzed by matrix-assisted laser desorption-ionization time-of-flight mass spectrometry, the results of which were compared with a curated protein sequence database for protein identification. One of the most frequently identified proteins, apoprotein (apo) A-I, was then quantified in all synovial fluid samples by use of a competitive-inhibition ELISA. Results were compared between dogs with and without osteoarthritis. RESULTS Median synovial fluid total protein and apo A-I concentrations for dogs with osteoarthritis were significantly greater than those for control dogs. The most abundant proteins identified in the synovial fluid were albumin and apo A-I. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that quantification of synovial fluid total protein and apo A-I concentrations might facilitate diagnosis of osteoarthritis secondary to CCLR in dogs. Further research and validation of synovial fluid apo A-I concentration as a biomarker for osteoarthritis in dogs are necessary before it can be recommended for clinical use.

Cell surface hydrophobicity of Mycoplasma hyopneumoniae was evaluated by phase partitioning in a hydro-carbon-aqueous mixture, by hydrophobic interaction chromatography, and by salting out with ammonium sulfate. Results obtained by use of these techniques gave evidence that the cell surface of M hyopneumoniae is weakly hydrophobic, compared with strongly hydrophobic Staphylococcus aureus Cowan I and hydrophilic Klebsiella pneumoniae. After treatment of the organisms with trypsin, M hyopneumoniae became less hydrophobic as measured by hydrophobic interaction chromatography. Significant changes in hydrophobicity were not seen after periodate treatment. Electron microscopy of M hyopneumoniae treated with polycationic ferritin revealed an intermediate, compact, unlabeled layer between the cytoplasmic membrane and an external, heavily labeled layer. Electron microscopy of ferritin-labeled M hyopneumoniae after treatment with trypsin or periodate revealed the intermediate layer to be composed of a trypsin-sensitive protein(s). The outer layer was made of periodate-sensitive carbohydrate(s). Therefore, it appears that proteins in the intermediate layer confer at least part of the total hydrophobicity of the mycoplasmal cell and may contribute to adherence of M hyopneumoniae to target respiratory cells by hydrophobic interactions.