Flush exposure and injection immunization of rainbow trout to selected DNP conjugates.

Rainbow trout (Salmo gairdneri) were immunized by flush exposure or intraperitoneal injection with single doses of the following dinitrophenyl (DNP) conjugates: DNP-keyhole limpet hemocyanin (KLH), DNP-Ficoll, DNP-O-antigen (from the fish pathogen, Yersinia ruckeri), DNP-sheep red blood cells, or DNP-duck red blood cells. The immune response was demonstrated by the passive hemolytic plaque assay to show splenic antibody-producing cells (APC) 14 days after antigen administration. High numbers of splenic APC specific for the hapten were found when the conjugates DNP-KLH, DNP-Ficoll, and DNP-O-antigen were given by injection and when DNP-O-antigen was given by flush exposure. The heterologous red blood cells were relatively nonimmunogenic. When the immune response to the hapten and carrier could be measured--e.g., after immunization with the DNP-O-antigen--the numbers of APC were consistently higher for the hapten.

Murine immune memory to a TI-2 antigen, DNP-Ficoll: carrier-specificity, genetic enhancement and phenotypic dominant inheritance.

C3H/HeN x NZB/BIN F1 mice were primed and challenged with DNP-Ficoll, a thymic independent (TI-2) antigen. They developed strong IgM and IgG carrier-specific memory responses: DNP-pneumococcal polysaccharide or DNP-haemocyanin challenge did not elicit memory responses. The IgG response component appeared to be inherited dominantly from the C3H/HeN parent. The IgM component resulted from genetic enhancement.

Immune memory to a nonmitogenic, thymic independent antigen in mice: variation among inbred strains and possible relationship to oncogenesis.

Immune memory to DNP-Ficoll, a nonmitogenic, thymic-independent (TI-2) antigen, was demonstrated in several inbred strains of mice. Direct and indirect splenic plaque-forming cell responses were measured in mice given a secondary challenge with DNP-Ficoll and in appropriate control mice. Strong IgM memory, but no IgG memory, was observed in SJL/J, AKR/J, and C58/J mice. C57L/J mice gave both a strong IgM memory response and a relatively strong IgG memory response to DNP-Ficoll. C57BL/6N, C57BR/cdJ, and A/HeJ mice were unable to mount significant IgM or IgG memory responses to this antigen under an identical immunization schedule. These results are indicative of marked genetic variation in mice in the capacity for B memory cell expression. They also identify a provocative but unexplained association between positive IgM memory responses to DNP-Ficoll in SJL/J, AKR/J, and C58/J mice and a propensity to develop lymphoreticular neoplasia. This association is observed when there is no clear evidence for IgG memory.

Evidence for an H-2-linked Ir gene regulating the immune response to a TI-2 antigen, DNP-Ficoll.

Various H-2 congenic mouse pairs were immunized with 10 microgram of DNP53-Ficoll, a thymic independent (TI-2) antigen. Four-day primary splenic immune responses were measured by a DNP-reactive PFC assay. Significantly different responses were noted between partners of many congenic pairs. An H-2 linked Ir gene for DNP-Ficoll appears likely.

Carrier-specific immune memory to a thymus-independent antigen in congenitally athymic mice.

Immune memory to the DNP epitope coupled to a nonmitogenic thymus-independent carrier, Ficoll, was demonstrated in congenitally athymic outbred Swiss mice. Strong IgM and modest IgG components of this memory were detected. Moreover, this memory was carrier specific since it was elicitable only when DNP-Ficoll primed mice were challenged with DNP-Ficoll and not when similarly primed mice were challenged with DNP coupled to pneumococcal polysaccharide or to keyhole limpet hemocyanin. Ficoll primed mice also demonstrated a memory response when challenged with DNP-Ficoll. These findings indicate that a non-T cell, presumably a B cell, is capable of recognizing the carrier epitopes of this thymus-independent hapten-carrier complex. Unlike their athymic counterparts, euthymic mice of the same genetic background failed to demonstrate the IgM component of this memory, but they did demonstrate modest carrier-specific IgG memory. These results strongly suggest that suppressor T cells are either directly or indirectly important in regulating the IgM memory response of these mice to DNP-Ficoll. Indirect regulation could possibly occur via an antibody-mediated specific immune suppression mechanism.

Isolation of the cytoplasmic granules of guinea pig basophilic leukocytes: identification of esterase and protease activities.

Procedures were developed for isolating highly purified cytoplasmic granules of basophilic leukocytes from guinea pig peripheral blood. The methods involved disruption of cells in 0.34 M sucrose followed by a series of membrane filtrations and fractionation on sucrose density gradients. These preparations, up to 95% pure basophil granules by electron microscopy, contained a mixture of neutral esterases-proteases including caseinolytic activity; both trypsin- and chymotrypsin-like serine hydrolases were identified by means of appropriate inhibitors. Localization of at least one such activity to the basophil granule was confirmed by a cytochemical method; this activity was absent in contaminating lymphocytes and eosinophils. By contrast, several lysosomal enzymes, lactic dehydrogenase, and plasminogen activator activity, present in cell homogenates, were absent from purified granules. The granule matrix of guinea pig basophils, unlike the cytoplasmic granules of other granulocytes or mast cells, was little altered by high or low salt concentration but was disrupted into insoluble fragments by 0.01 N HCl and by Triton X-100. Granules were solubilized by papain and by urea-SDS but enzyme activity was destroyed. Triton X-100 incubation with freeze-thawing proved to be the optimal method for extracting esterase activities. Esterase activities were not released from basophils under conditions of anaphylactic degranulation that liberated the great majority of basophil granule histamine.

F-antigen: nature, liver specificity, and release in experimental liver injury.

F-antigen is a liver-specific antigen detected with antibody, raised in allogeneic (CBA) mice, to BALB/c mouse liver extract. The authors have confirmed the hepatic specificity of this antigen by showing it to be absent in extracts of extrahepatic organs of mouse and human origin. It is present in liver extracts of guinea pigs, rats, and rabbits, as well as in liver extracts from mouse and human sources. The antigen was present in the circulation of rabbits with acute carbon tetrachloride-induced hepatocellular injury. It was also demonstrated in the sera of 3 of 8 patients with acute hepatitis B antigen-positive hepatitis and in 1 of 4 patients with chronic active hepatitis. It was absent from the sera of 121 other patients with a variety of hepatic and nonhepatic diseases, and from the sera of 20 healthy subjects. The antigen is immunologically distinct from hepatitis B antigen, from the liver-specific lipoprotein antigen LP-2 of Meyer zum Buschenfeld, and from each of 15 individual human serum proteins tested.