Evaluation of phagocytosis, bactericidal activity, and production of superoxide anion, nitric oxide, and tumor necrosis factor-alpha in Kupffer cells of neonatal pigs.

OBJECTIVE

To evaluate the activity of Kupffer cells (KC) of control neonatal pigs and neonatal pigs treated with endotoxin and to compare activity of KC with that of pulmonary alveolar macrophages (PAM).

METHODS

Kupffer cells and PAM obtained from 24 neonatal pigs (7 to 10 days old).

METHODS

Pairs (n = 7) of littermates served as treated (lipopolysaccharide [LPS]) or untreated pigs. Pigs were euthanatized 24 hours after treatment, and cells were isolated. Cells were obtained from 10 other neonatal pigs for other assays. Functional activity of cells was evaluated by use of in vitro assays to evaluate bactericidal activity, phagocytosis, and production of superoxide anion (SOA), nitric oxide (NO), and tumor necrosis factor-alpha (TNF-alpha). Each assay was repeated on cells obtained from 4 to 6 pigs.

RESULTS

Phagocytic activity was similar in KC and PAM, but bactericidal activity and production of SDA and TNF-alpha was lower in KC. Neither KC nor PAM produced NO in response to LPS stimulation. Phagocytosis, bactericidal activity, and production of SOA were enhanced for KC obtained from neonatal pigs treated with LPS. The PAM from LPS-treated neonatal pigs had similar bactericidal activity to PAM obtained from untreated pigs.

CONCLUSIONS

Functional capacity of KC is affected by endotoxin. This provides additional information of the role the liver plays in immune surveillance. In addition, the response of KC in neonatal pigs exposed to endotoxin is of value for understanding gram-negative bacterial sepsis, which is a major cause of mortality in neonatal pigs.