The response of the hepatic lymph node of the sheep to swine influenza virus.

Abstract

SummaryThe primary and secondary responses of the hepatic lymph node to Swine influenza virus were studied following the injection of the virus intravenously or locally beneath the liver capsule. The hepatic lymph node did not respond in a detectable manner to a primary intravenous injection of virus and the antibody titres in the blood plasma were low. Following a second intravenous injection of virus, there was a slight cellular response in the efferent lymph from the hepatic node. The antibody response was vigorous and typically secondary, and it appeared that some antibody was synthesized in the hepatic node.Primary and secondary responses to the injection of virus beneath the liver capsule were characterized by a significant cellular reaction in the efferent lymph with the appearance of basophilic cells. Antibody titres in both blood and lymph were higher than those which followed primary or secondary intravenous injections. There was no correlation between the appearance of basophilic cells in the lymph and the appearance or persistence of antibody in the lymph in the primary response.The reactions of the hepatic node to influenza virus indicated that there was no immunological liaison between the phagocytic cells in the liver and the afferent hepatic lymph and the regional lymph node of the liver. These phagocytic cells do not therefore have a role in processing antigens as a prelude to an immune response.