Comparison of α2-macroglobulin synthesis by juvenile vs. mature rats after identical inflammatory stimulation.

Synthesis of α2-macoglobulin (α2M) by 3-week-old juvenile rats was compared to that of mature 7- and 11-week-old rats. Serum concentrations of α2M, interleukin (IL)-6- and cytokine-induced neutrophil chemoattractant (CINC)-1 were measured by enzyme-linked immunosorbent assay. The area under the concentration vs. time curve (AUC) for α2M was significantly different among the three groups. The synthesis of α2M increased in an age-dependent manner. No significant difference was observed for the AUC of IL-6, but that of CINC-1 in 3-week-old rats was significantly lower than that in 7- or 11-week-old rats. These results suggest that synthesis of α2M was increased in mature compared to juvenile rats, possibly due to differences in liver function. The maximum concentration of CINC-1 in 3-week-old rats was observed 6 h after turpentine oil injection. The serum concentrations of IL-6 and CINC-1 increased more quickly in juvenile rats than in mature rats after inflammatory stimulation.

Determination of antibody titers against soluble antigen by indirect fluorescent antibody (IFA) assay using latex particles coupled with soluble antigen: a preliminary study.

A method for indirect fluorescent antibody (IFA) assay for soluble antigen has been developed using latex particles (latex) as a carrier for soluble antigen. Two types of latex having grain sizes of 1.0 and 6.0 µm were used for IFA assay and were evaluated in this study. Bovine IgG and rabbit anti-bovine IgG antibody were used as soluble antigen and as primary antibody, respectively. Bovine IgG-sensitized latex on slide glass was not washed off after immersion for 45 min. IFA using latex appears to have high specificity, as no reactions between fluorescein isothiocyanate (FITC)-conjugated antibody and protein-sensitized latex were observed, and the latex did not show auto-fluorescence or non-specific reactions. Latex with a grain size of 6.0 µm was appropriate as a carrier of soluble antigen, as the amount of soluble antigen necessary for sensitization was approximately one-eighth that necessary for the small-diameter latex (1.0 µm), and large-diameter latex is easier to distinguish under the fluorescence microscope. IFA assay using soluble antigen-sensitized latex is suitable for more widespread use in the future.

Carbonic anhydorase isoenzyme I (CA-I) concentration in feces and urine as a temporary marker of occult blood in beagle dogs.

This study was undertaken to investigate whether the concentration of carbonic anhydorase isoenzyme I (CA-I) in canine feces and urine is useful as a temporary marker of occult blood. Concentrations of CA-I were measured by enzyme-linked immunosorbent assay (ELISA). Fecal CA-I concentrations in 113 healthy beagle dogs (50 male and 63 female) of various ages ranged from 4.3 to 16.7 ng/g feces (mean; 7.0 +/- 2.9 ng/g feces). One milliliter of blood from 3 healthy beagle dogs was found to contain 1,047, 1,062 and 1,150 microg CA-I. The fecal CA-I concentrations of dogs receiving intragastric infusions of autologous blood (10 ml) were very low. However, the fecal CA-I concentrations of dogs receiving infusion of autologous blood (5 ml) into the ascending colon were very high. Detection of fecal CA-I would be useful for identifying dogs with hemorrhaging of the large intestine. Of 55 urinary samples collected from healthy beagle dogs by catheter, chemical tests for occult blood were negative in 44, but CA-I concentrations ranged from 1.8 to 12.6 ng/ml (mean; 6.9 +/- 5.4 ng/ml) by ELISA. The CA-I concentrations of the other 11 samples, which tested positive for occult blood on chemical testing, ranged from 41.2 to 525.0 ng/ml by ELISA. Although CA-I is not a specific marker of erythrocytes, CA-I may be used to detect occult blood in canine feces and urine until a specific immunological test kit using antibody for Hb is developed.

Determination of serum C-reactive protein (CRP) in healthy beagle dogs of various ages and pregnant beagle dogs.

Serum C-reactive protein (CRP) concentrations in healthy beagle dogs of various ages and in pregnant beagles were measured by enzyme-linked immunosorbent assay (ELISA). Serum CRP concentrations were 1.5-16.0 microg/ml (mean 7.9 +/- 3.4 microg/ml) in male, and 1.8-18.9 microg/ml (mean 8.3 +/- 4.0 microg/ml) in female dogs. No significant sex-related differences were observed in the values. Further, there were no significant age-related differences either. Serum CRP concentrations increased during pregnancy. The concentration of serum CRP in pregnant dogs peaked at 70.2-90.4 microg/ml (mean 77.5 +/- 7.1 microg/ml) 30 or 45 days after ovulation, demonstrating two characteristic features of CRP concentration change in pregnant dogs.