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-10, or TNF-α expression did not significantly differ with age, but IL-1β and IL-8 expression appeared to increase with age. Interleukin-1 plays an important role in nonspecific immunologic defense, and IL-8 is an important proinflammatory chemokine

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in American Journal of Veterinary Research

cytokine production. Interleukin-10 is a part of the host protective mechanisms during endotoxemia. 1 In the present study, epinephrine and norepinephrine increased LPS-stimulated production of IL-10, which is similar to that observed in a study 17 with

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in American Journal of Veterinary Research

rates. 6–8 Inflammation associated with transfusion results, in part, from the accumulation of cytokines in stored blood products. 1,2 Interleukin-1β, IL-8, and TNF-α are cytokines that increase in concentration in human whole blood and PRBCs during

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in American Journal of Veterinary Research

transcription-6. 15 Interleukin-4 also appears to regulate the transcription factors p38, mitogen-activated protein kinase, and phosphoinositide-3 kinase in neutrophils, as their activity is correlated with an upregulation of mRNA for cell differentiation

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in American Journal of Veterinary Research

SUMMARY

Six nonpregnant, nonlactating Jersey cows, averaging 4 to 6 years old, were used to evaluate the immunomodulatory effects of recombinant bovine interleukin 1β (rBoIL-1β). Cows were given 166 ng of rBoIL-1β/kg of body weight at 8-hour intervals for 96 hours. Persistent leukocytosis was observed within 3 hours of rBoIL-1 treatment, peaking 24 hours after the first IL-1β injection and returning to baseline values within 72 hours after cessation of IL-1β treatment. Injection of cows with rBoIL-1β stimulated lymphocyte blastogenesis and mitochondrial methyl-thiazoltetrazolium cleavage activity in resting cell cultures. Increases in the aforementioned lymphocyte activities were also observed in stimulated blood mononuclear cell cultures during IL-1β administration. Change in IgM production in cell cultures was not observed during IL-1β treatment. Within 24 hours of the first IL-1β injection, IL-1β mRNA transcription in stimulated blood mononuclear cell cultures was markedly increased, suggesting that IL-1β upregulates its own production in mononuclear cells. These data provide evidence that administration of cytokines, such as rBoIL-1β, enhances immune cell function and, therefore, may be useful in alleviating immunosuppression in cattle.

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in American Journal of Veterinary Research

Summary

Serum interleukin-6 (il-6) concentration was measured in 11 colostrum-fed (cf) and 8 colostrum-deprived (cd) 2- to 3-day-old foals after foals were infused with lipopolysaccharide (lps; Escherichia coli O55:B5 endotoxin, 0.5 µ.g/kg of body weight in sterile saline [0.9% NaCl] solution). Four cf and 2 cd foals were given saline solution alone. Serum il-6 concentration was estimated by use of an in vitro proliferative bioassay, using the IL-6 dependent B.13.29 clone 9 cells. Interleukin-6 concentration increased in all lps-infused foals, and geometric mean serum il- 6 concentration was significantly higher in cf than cd foals 30 and 90 minutes after infusion. Both lps- infused groups had multiple spikes of mean il-6 concentration that peaked at 120 minutes in cf foals and 150 minutes in cd foals. Results indicated that il-6 is produced in neonatal foals in response to lps infusion. Furthermore, colostrum deprivation resulted in longer times to peak mean serum il-6 concentration and tended to reduce serum il-6 concentration in neonatal foals.

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in American Journal of Veterinary Research

SUMMARY

Interleukin-1 (il-1) is a protein secreted by stimulated cells of the monocyte-macrophage line, which has a number of important biologic activities. Interleukin-1 has been implicated in the induction and augmentation of the pathologic processes involved in arthritis and articular cartilage destruction. Horses develop osteoarthritis with a frequency and degree of severity similar to human beings. To further document the similarity of the osteoarthritic process in people and horses, the synovial fluid from 5 horses with clinical osteoarthritis was tested for il-1 bioactivity. Interleukin-1 activity was found in all tested synovial fluids. Upon column chromatography, the synovial fluid-derived factor had a molecular weight consistent with that of il-1 in other mammalian species. Ion exchange chromatography of osteoarthritic synovial fluid revealed the principal peaks of bioactivity to be in the fractions with isoelectric points of 7.2, 5.4, and 4.7, which are characteristic of il-1. A considerable degree of homology between human and equine il-1 was demonstrated by the cross hybridization of a human il-1β cDNA probe with rna derived from il-1-producing equine adherent monocytes. These results indicate that equine il-1 is in all of the osteoarthritic equine joints tested and that equine il-1 has many of the characteristics of il-1 isolated from other species.

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in American Journal of Veterinary Research

SUMMARY

The relative sensitivity of bovine blood monocytes and macrophages isolated from milk to lipopolysaccharide, with respect to interleukin 1 (il-1) production, was evaluated. Addition of lipopolysaccharide (0 to 30 μg/ml) to the culture medium resulted in increases in secreted and intracellular il-1 activity for monocytes and milk macrophages, with maximal stimulation achieved at 30 μg of lipopolysaccharide/ ml of medium. At this concentration of lipopolysaccharide, monocytes released 76% of the total il-1, whereas milk macrophages released only 26% of the total il-1 produced within the cell. Secretion of a small quantity of il-1 was a common property of macrophages isolated from healthy and mastitic quarters. We concluded that limited secretion of il-1 may render the milk macrophages less efficient in promoting lymphocyte activation.

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in American Journal of Veterinary Research

Summary

The immunomodulating polypeptide interleukin 1β (il-1β) has been shown to be homologous to osteoclast-activating factor and is capable of stimulating increased osteoclastic bone resorption. This effect prompted an investigation into the potential use of il-1β for prevention of parturient paresis, a disease of dairy cows characterized by hypocalcemia and poor osteoclastic resorption of bone. Six nonpregnant cows were treated with a high dosage of il-1β (166 ng/kg of body weight) every 8 hours for 4 days. The il-1β treatment significantly (P < 0.05) increased urinary hydroxyproline excretion, an index of osteoclast activity, indicating that bone calcium resorption might be stimulated by il-1β treatment of cows. However, il-1β treatment also caused transient fever, inappetence, increased pulse and respiratory rate, and diuresis. The acute, but transient, effect of il-1β treatment was to cause a decrease in plasma calcium and phosphorus concentrations. The pleiotropic effects of il-1β administration negated the positive effects on osteoclastic bone resorption, and indicates that this cytokine may be of minimal benefit for prevention of parturient paresis.

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in American Journal of Veterinary Research

Abstract

Objective

To clone and characterize the cDNA encoding feline interleukin-5 (IL-5) cDNA and the 170 basepairs (bp) of the 5' flanking region of the feline IL-5 gene.

Sample Population

Blood mononuclear cells from a healthy cat.

Procedures

Cells were cultured, stimulated for 48 hours with concanavalin A, and harvested for RNA and DNA isolation. Recovered RNA was used in northern blot and reverse transcription-polymerase chain reaction analyses. Resulting cDNA was used for rapid amplification of 3' cDNA ends, dideoxy chain termination sequencing, and primer extension analysis.

Results

Full length cDNA was 838 bp, including a 402-bp open reading frame that encoded a precursor protein of 134 amino acids including a putative peptide signal of 19 residues. Homologies of the nucleotide and derived protein sequences between feline and human IL-5 cDNA were 72 and 71%, respectively. There also was homology between the human and predicted feline cytokines at amino acid positions that are critical for IL-5 receptor binding and signal transduction. The 5' flanking region of the feline gene was homologous to corresponding regions of the human (88%) and murine (72%) genes, and included putative transcriptional regulatory elements.

Conclusions and Clinical Relevance

Identification of feline IL-5 cDNA is an important step toward a detailed, fully comprehensive characterization of the mechanisms that may be operative in the pathogenesis of eosinophilic disorders in cats. The striking homology between the human and feline IL-5 genes suggests that cats can be used as animal models for human diseases characterized by eosinophil infiltration of tissues. (Am J Vet Res 1998;59:1263–1269)

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in American Journal of Veterinary Research