Genetic association of the humoral and cellular immune responses of rats to Moloney sarcomas

Brown Norway (BN), Lewis (Le), F1 hybrids of LexBN (LBN) and parent-to-LBN backcross rats were tested for cellular and humoral responses to a BN Moloney sarcoma. Regardless of AgB phenotype, BN backcrosses produced low levels of cell-mediated cytotoxicity (CMC) that were comparable to those of BN parents. Le backcrosses developed high levels of CMC similar to those produced in Le parents. An inverse relationship between levels of CMC and serum antibodies (cytotoxic for tumor cells and anti-p30 of MuLV) was observed; BN parents and backcrosses produced high levels of serum antibodies whereas levels in Le parents and backcrosses were low. LBN hybrids developed relatively high levels of CMC and serum antibodies. An additional finding was that the CMC response in Le parents and back-crosses was directed primarily against tumor-associated antigens rather than histocompatability antigens expressed on the tumor cells. The results suggest that humoral and cellular responses to Moloney sarcoma in rats are not determined solely by the major AgB histocompatibility locus but do have a genetic association. This genetic association was detected with a 51Cr release assay which detects T-cells, suggesting that select populations of effector T-cells may be genetically regulated.

Morphological and antigenic relationships between viruses (rotaviruses) from acute gastroenteritis of children, calves, piglets, mice, and foals

The reovirus-like particles present in the feces of young pigs and foals with acute enteritis and the virus causing epizootic diarrhea of infant mice were found to be indistinguishable morphologically from each other, from the South African SA. 11 and "O" viruses, and from the rotaviruses of children and calves. The inner capsid layer of each of these viruses reacted seriologically with sera of children, calves, mice, piglets, and foals convalescent from infection with their respective rotaviruses. These sera reacted by immunofluorescence with human, bovine, porcine, and murine rotaviruses, SA.11, and "O" viruses in tissue cultures and with human bovine, procine, nad murine viral antigens by complement fixation and gel diffusion. However, the antisera differed in their ability to react serologically with the outer capsid layer of the viruses investigated and in their ability to neutralize tissue culture-adapted calf virus. These two tests may demonstrate strain or host specificity among rotaviruses. Since the porcine, murine, and equine viruses are closely related serologically to and are morphologically identical to the human and bovine viruses, they should be included in the group of viruses for which the term "rotavirus" has been suggested. All known members of this proposed group of viruses share a common antigen, probably situated within the inner capsid layer; thus, any one of the viruses may be used for the preparation of antigen or antibody for diagnostic tests, and this will aid in the diagnosis of virus infection in those species from which a rotavirus has not been cultured.

The isolation of reovirus-like agents (rota-viruses) from acute gastroenteritis of piglets

Isolations of reovirus-like agents (rotaviruses) were made from nine of 23 outbreaks of piglet diarrhoea on different farms and from both weaned and unweaned piglets. The viruses were shown to be morphologically and anti-genically similar to the rotaviruses of children and calves. Gnotobiotig piglets given intranasal inoculations of five different isolates developed acute gastroenteritis, and the virus was re-isolated from the faeces or intestinal contents. The piglet virus was not adapted to replicate in cell culture. We conclude that the pig rotavirus is commonly associated with outbreaks of gastroenteritis and is probably an important aetiological factor in this disease.

Kinetics of the antibody response to type III pneumococcal polysaccharide. I. Evidence that suppressor cells function by inhibiting the recruitment and proliferation of antibody-producing cells

For the first 126 hr after immunization of mice with an optimally immunogenic dose (0.5 mug) of Type III pneumococcal polysaccharide (SSS-III), splenic antibody-forming PFC and serum antibody levels were measured at 2- and 8-hr intervals, respectively. PFC were detected at 28 hr after immunization and then increased through 86 hr after immunization; thereafter, the number of PFC remained nearly constant for the next 20 to 24 hr, and then began to decline. In contrast, serum antibody was first detected 60 hr after immunization. The accumulation of serum antibody continued to lag behind the increase in numbers of PFC by 16 to 20 hr until maximal serum antibody levels were attained; curves fitted to the values obtained for each parameter were nearly parallel.

Kinetics of the antibody response to type III pneumococcal polysaccharide. II. Factors influencing the serum antibody levels after immunization with an optimally immunogenic dose of antigen

When the number of PFC present in the spleen was measured at 24-hr intervals after immunizing with an optimally immunogenic dose of type III pneumococcal polysaccharide (SSS-III), maximal numbers of PFC were attained 4 days after immunization; thereafter, the number of PFC decreased rapidly. By contrast, serum antibody levels, which were measured in the same mice using a Farr test, reached peak values 5 days after immunization and then declined much more slowly than did the number of PFC. Two factors were found to contribute to this disparity. First, experiments conducted with splenectomized mice showed that extrasplenic antibody synthesis, which began between days 3 and 4 after immunization and peaked on days 6 to 7, accounted for nearly one-third of the total amount of serum antibody produced. Second, the average rate of antibody synthesis by PFC increased through day 6 after immunization and then declined. Antigen-antibody dissociation tests showed that the avidity of the serum antibody obtained 4 to 7 days after immunization was the same. Moreover, during the same interval, all the antibody detected by the Farr test was of the IgM class. Thus, a change in avidity or class of immunoglobulin after day 5 did not account for the disparity observed. The clearance rate of antibody injected i.v. into nonimmune and immunized mice was studied. The data obtained indicated that accelerated clearance of antibody was occurring prior to day 3 after immunization; however, after day 3 the antibody clearance rate was constant and was the same as that found when antibody was injected into nonimmune mice. These findings affirmed the results of previous studies showing that treadmill neutralization was not important in determining the serum antibody levels present after immunization with an optimally immunogenic dose of SSS-III.

Kinetics of the antibody response to type III pneumococcal polysaccharide (SSS-III). I. Use of 125I-labeled SSS-III to study serum antibody levels, as well as the distribution and excretion of antigen after immunization

A simple method was described for the preparation of 125I-labeled type III neumococcal polysaccharide (SSS-III) with a high specific radioactivity which retained the physical and immunologic properties of native SSS-III. SSS-III was used to study the serum and tissue levels of antigen, as well as its excretion, after i.p. injection. When an optimally immunogenic dose (0.5 mug) of antigen was given, greater than 90% of the injected antigen was excreted during the first 3 days after injection; however, after day 3, the SSS-III which remained in each mouse was firmly bound to various tissues, and less than 5 ng SSS-III was released into the circulation daily. SSS-III was also used in a Farr test to measure serum antibody levels; the kinetics for the appearance of PFC/spleen and serum antibody levels were measured at 24-hr intervals after immunization with 0.5 mug of antigen. Maximum PFC/spleen were observed on day 4 after immunization whereas the peak serum antibody level was seen on day 5. The decay of serum antibody level from its maximum value was much slower than that of the PFC/spleen. The data describing the distribution of SSS-III in vivo and the measurement of serum antibody levels indicated that treadmill neutralization was not a factor in determining the serum antibody levels after immunization with an optimally immunogenic dose of SSS-III.

Transmission of human rotaviruses to gnotobiotic piglets

Faecal filtrates containing rotavirus particles, from children with acute infectious diarrhoea, were inoculated intranasally into gnotobiotic piglets. The piglets developed no symptoms, but birus was readily found by electron microscopy in their faeces during three serial passages. Among 11 piglets tested 3 weeks after inoculation of virus, all had developed fluorescent antibodies against tissue-culture-adapted calf rotavirus but only two had neutralising antibody. Growth of human rotavirus did not occur in either normal or "nude", thymus-deficient suckling mice.

Alloantigen expression of a rat Moloney sarcoma

Cells of a brown Norway (BN) rat Moloney sarcoma (MST) failed to express certain BN alloantigen specificities and bound only about 30-50% the amount of labeled alloantibody bound by normal BN spleen cells. MST cells lacked antigen specificities shared by BN and WF rats, but expressed some of the antigen shared by BN and AUG rats. Further loss of alloantigens that occurred with prolonged in vitro culture was associated with reduced virulence of MST cells for syngeneic hosts and with increased expression of tumor-associated antigens. The LEW rats, which are resistant to MST cells, might have rejected the tumor on the basis of factors other than Ag-B antigens.

Soluble membrane antigen fractions that react with rat enhancing alloantibodies

Soluble extracts were prepared from cells of Brown Norway (BN) rat spleens by sonication in 2 M KI. Extracts were fractionated by gel filtration and electrophoretic procedures. The fractions specifically inhibited the binding of Lewis alloantibodies to target BN cells in vitro and in vivo. A homogeneous component that retained antigen activity was obtained by preparatory polyacrylamide gel electrophoresis. Lewis rats injected with BN antigen fractions produced histocompatibility alloantisera that would prolong the survival of BN skin grafts applied to Lewis neonates.

Relations of personality factors and student nurses' attitudes toward abortion

The present study, conducted just prior to the 1973 U. S. Supreme Court decision on abortion, focused on effects of personality characteristics and one health-profession choice (student nursing vs a liberal arts major) upon attitudes toward abortion. Ss were 96 students from an introductory psychology class, 49 student nurses, and 46 liberal arts majors. It was predicted that student nurses would be more negative toward legalizing abortion than would liberal arts majors. Results supported this prediction ( p < .025). Personality characteristics were assessed by the 16 PF (Cattell, Eber, & Tatsuoka, 1970) and were analyzed to yield four second-order factors: anxiety vs adjustment, extraversion vs introversion, subduedness vs independence, and tender-minded emotionality vs alert poise. Anxiety, introversion, subduedness, and tendermindedness were all expected to predispose Ss to be more against abortion than the other halves of these dichotomies. Predictions were supported ( ps from .05 to .025) for all but anxiety.

Contact sensitivity in vitro: activation of actively allergized lymphocytes by a beryllium complex

Beryllium either as salts or in a complexed form was studied for its ability to trigger lymphocytes from guinea pigs painted with beryllium fluoride. The triggering was assessed by assaying and partially characterizing culture supernatants for macrophage migration inhibition factor. It was found that beryllium complexed to the ligand sulphosalicylic acid was able to induce macrophage inhibition factor (MIF) formation. The insoluble beryllium oxide and the immunizing agent beryllium fluoride did not produce MIF. Data is presented which would support a direct interaction of beryllium sulphosalicylate with cells without prior complexing to macromolecules.