Canine malignant lymphomas: comparison of morphologic and immunologic parameters.

Twenty-three canine malignant lymphomas were studied to correlate morphologic and immunologic properties of the neoplastic cells. Morphotologic characterization included histologic classification of cell type and growth pattern, anatomic distribution of lesions, and transmission electron microscopic examination. Parameters examined to indicate B- or T-cell nature of lymphoma cells included demonstration of mitogen responsiveness, cell-surface Ig, spontaneous rosette formation with human red blood cells, and scanning electron microscope (SEM) examination of cell-surface features. Results indicated that the cells from histiocytic lymphomas were lymphocytes rather than histiocytes or macrophages. Most cells from lymphomas examined possessed cell-surface ig, indicating B-cell nature. The cell types represented by the different Ig-positive lymphomas were compatible with maturation arrest at different stages in normal lymphocyte differentiation. For the two most common histiologic cell types, nitogen responsiveness and the presence of cell-surface Ig indicated that diffuse, poorly differentiated lymphocytic cases were biologically heterogenous, whereas nodular histiocytic lymphomas were biologically homogenous. Most canine lymphomas had a multicentric anatomic distribution; however, one thymic and two alimentary forms were observed. Lymphomas with a nodular pattern in lymph nodes had multifocal splenic involvement centered on small arteries, whereas lymphomas with a diffuse pattern in lymph nodes had diffuse involvement of splenic white pulp. The cells of Ig-positive and Ig-negative neoplasms examined by SEM were predominantly of the smooth-cell type.

Inhibition of human lymphoma DNA-dependent RNA polymerase activity by 6-mercaptopurine ribonucleoside triphosphate.

6-Mercaptopurine was found to inhibit the growth of cultured human lymphoma P3HR-1 cells and the incorporation of [3H]-uridine into trichloroacetic acid-precipitable materials of the cells. One of the derivatives of 6-mercaptopurine, 6-mercaptopurine ribonucleoside triphosphate (6-thio-ITP), was found to inhibit in vitro RNA synthesis (both engaged and free enzyme activities) of the isolated nuclei from P3HR-1 cells. The alpha-amanitin-resistant RNA polymerase (polymerase I) and alpha-amanitin-sensitive RNA polymerase (polymerase II) of the cells were isolated and partially purified by either diethylaminoethyl cellulose or diethylaminoethyl Sephadex column chromatography, followed by DNA-cellulose affinity chromatography. It was found that these partially purified enzymes were also sensitive to 6-thio-ITP inhibition. Kinetic studies showed that the inhibition of RNA polymerase activities by 6-thio-ITP could be reversed by increasing concentrations of guanosine 5'-triphosphate in the reaction mixture, indicating that 6-thio-ITP may act as a competitive inhibitor of the enzymes by competing with guanosine 5'-triphosphate for its enzyme-binding site. These data suggest that inhibition of RNA transcription by 6-thio-ITP may be considered as one of the mechanisms of the cytotoxic action of 6-mercaptopurine in human tumor cells.

Virulence factors in Escherichia coli isolated from the blood of bacteremic neonatal calves.

Twenty-five Escherichia coli isolates from the blood of critically ill bacteremic calves sampled in two separate studies on a calf-rearing farm housing over 15,000 calves, in the San Joaquin Valley, California were studied. Isolates were characterized for O serogroups and for pathotypes as determined by the presence of specific virulence factors including heat-labile enterotoxin (LT), heat-stable enterotoxins a and b (STa, STb), verotoxins 1 and 2 (VT1, VT2), cytotoxic necrotizing factor (CNF), aerobactin, intimin Eae and P, F17 and CS31A fimbrial adhesins, and resistance to bactericidal effects of serum. These isolates constituted a heterogeneous group. However, isolates were mostly aerobactin positive and often resistant to the bactericidal effects of serum. Isolates of pathotypes O78 (n=6), O119:CS31a (n=3), and P positive but O non-typeable (n=3) were associated with a high mortality rate. The remaining isolates belonged to diverse pathotypes, often possessing the adhesins P, F17, CS31A and Eae but belonging to O serogroups other than O78 and O119, and were less frequently associated with mortality. Although no virulence factor common to all isolates was identified, the capacity to use iron by the presence of aerobactin which is important to the capture of iron was a predominant factor. Moreover, certain pathotypes appear to be associated with primary colisepticemia whereas other pathotypes may cause a bacteremia without necessarily leading to septicemia.

Cytotoxic immune response of puppies to feline sarcoma virus induced tumors.

The cytotoxic immune response of puppies to feline sarcoma virus induced tumors was studied. Neonatal puppies were compared with adolescent dogs. Three different types of cytotoxicity were investigated: complement dependent cytotoxicity, T-cell-mediated cytotoxicity and antibody dependent cellular cytotoxicity. The relationship between the spontaneous regression of the sarcoma and the development of the immune system of the puppies is discussed.

Hemolytic complement measurement in eleven species of nonhuman primates.

A microtiter system was used to measure hemolytic complement levels in serum from eleven nonhuman primate species. The species studied were Macaca mulatta (rhesus macaque), Macaca radiata (bonnet macaque), Macaca nemestrina (pig-tailed macaque), Macaca fascicularis (crab-eating macaque), Macaca speciosa (stumptailed macaque), Papio cynocephalus (yellow baboon), Papio anubis (olive baboon), Cercopithecus aethiops (African green monkey), Aotus trivirgatus (owl monkey), Ateles fusceps robustus (spider monkey), and Galago crassicaudatus panganiensis (thick-tailed galago). The optimal hemolytic complement titer of the various nonhuman primate species was found to vary with different species sources of erythrocytes and anti-erythrocyte reagents used in the assay. No single erythrocyte and anti-erythrocyte test reagent produced optimal titers for all of the primate species examined. Sera from several species was found to have high spontaneous lytic activity towards non-sensitized sheep erythrocytes which for six species (M. mulatta, M. radiata, M. speciosa, P. cynocephalus, P. anubis and A. trivirgatus) was equal to the titer for antibody sensitized erythrocytes. Evidence of alternate pathway complement activation as a possible reason for the high titer of lytic activity towards unsensitized erythrocytes could not be demonstrated for any nonhuman primate species. In one species, M. mulatta, the sensitizing activity of normal serum for sheep erythrocytes was shown to be in the IgM containing fraction obtained with gel filtration and to be absorbed by boiled sheep erythrocyte stroma which contains Forssman antigen.

Characterization of rhesus macaque peripheral blood T-lymphocyte subpopulations.

Highly enriched rhesus macaque (Macaca mulatta) peripheral blood T-lymphocytes were separated into functional subpopulations by Fc-receptors. The T-lymphocyte population was comprised of both Fc-IgM (T mu +, 3.4 +/- 1.6) and Fc-IgG (T gamma +, 16.2 +/- 4.0) bearing cells. T-cells depleted of cells bearing Fc-IgG receptors (T gamma -) and T gamma + subpopulations were characterized and assessed for functional activity. T gamma + and T gamma - subpopulations were found to have the following characteristics: 1) T gamma + cells were stimulated by concanavalin-A (Con-A)3, pokeweed mitogen (PWM), and phytohemagglutinin-P (PHA-P), while T gamma - cells were stimulated by Con-A and PWM, but not PHA-P; 2) T gamma - cells were found to mediate PWM induced differentiation of autologous B-cells including EAC+ and EAC- enriched subpopulations, while T gamma + cells did not induce differentiation; 3) T gamma + cells released soluble factors which depressed mitogen stimulation of T gamma- cells; and 4) approximately 8-10% of the T gamma + cells phagocytized IgG sensitized bovine red blood cell (BRBC) immune complexes.

Relationships between maternal and fetal liver copper, iron, manganese, and zinc concentrations and fetal development in California Holstein dairy cows.

Associations between maternal trace element deficiencies and abortion have been made for many mammalian species. Objectives of this study were to estimate and correlate maternal and fetal hepatic Cu, Fe, Mn, and Zn concentrations through gestation. Additionally, aborted fetuses, stratified by cause of abortion (infectious or noninfectious), were compared to size-matched nonaborted fetuses to examine for magnitude and direction of change in hepatic trace element status. Dam and fetal liver were removed at slaughter from 103 Holstein dairy cows judged grossly normal by ante- and postmortem examination. Liver samples were collected from fetuses submitted by veterinarians for routine diagnosis of abortion (n = 80). Hepatic Cu, Fe, Mn, and Zn concentrations were determined by flame spectrophotometry. Comparisons of groups, estimations of correlations, and derived prediction equations were made by least-squares methods. Maternal liver Cu, Fe, Mn, and Zn concentrations did not vary during gestation. Compared with the dam, fetal liver Fe and Zn concentrations were higher (P < 0.05), fetal Cu concentrations were similar (P > 0.05), and fetal liver Mn concentrations were lower (P < 0.05). As fetal size increased, fetal liver Cu and Zn concentrations increased (P < 0.05), fetal liver Fe concentration decreased (P < 0.05), and fetal liver Mn did not change (P > 0.05). Aborted fetuses had lower liver Cu, Mn, and Zn concentrations than did nonaborted fetuses (P < 0.05). Liver Fe concentration was lower in aborted fetuses than in nonaborted fetuses in the second trimester only (P < 0.05). Consistently lower liver Cu, Fe, Mn, and Zn concentrations in aborted fetuses suggest a nonspecific change in trace element status, which implies an effect of abortion, not a cause of abortion.

Bovine ketosis and somatotrophin: risk factors for ketosis and effects of ketosis on health and production.

Aspects of the metabolism and health of 63 cows which had been treated with different amounts of bovine somatotrophin (BST) daily in the preceding lactation and 25 control cows were studied. The aims of the study were first, to identify cows with ketotic conditions, either by measurements of blood metabolite concentrations or by clinical observations, secondly, to evaluate the risk of such conditions in cows treated with BST in the preceding lactation, and thirdly, to examine the metabolic and production consequences of the ketotic conditions in an environment in which the cows' health, body condition and nutrition were closely observed. The cows were categorised objectively by the use of cluster analysis into non-ketotic cows and ketonaemic cows, on the basis of their plasma metabolite concentrations. Twelve of the control cows and none of the cows previously treated with BST were classified as ketonaemic. Similarly, nine of the control cows but only two of the cows previously treated with BST had clinical ketosis. Some, but not all, of the decrease in the risk of clinical ketosis was attributable to the lower body condition score of the cows previously treated with BST. The clinically ketotic cows had a greater risk of other illness in the first 10 days post partum than their herdmates, but the ketonaemic cows had a significantly lower risk of other disease in the first 10 days post partum. The ketonaemic control cows were significantly heavier than the non-ketotic control cows, but they maintained a higher dry matter intake than the latter cows, probably a key factor in reducing the risk of clinical ketosis.

Factors associated with in utero or periparturient transmission of bovine leukemia virus in calves on a California dairy.

A three-year prospective study involving 143 calves born from infected cows was undertaken on a California dairy to evaluate possible factors of the dam associated with bovine leukemia virus infection in utero or during the periparturient period. In utero or periparturient infection occurred at a rate of 4.8% and was more likely in calves born to cows with an average peripheral blood lymphocyte count during pregnancy greater than 12,000 cells/microL (p = 0.043) or in calves born to cows that developed malignant lymphoma (p = 0.00004), but not in calves born to cows with p-24 antibodies (p = 0.675).

Induction of mycoplasmosis in goat kids by oral inoculation with Mycoplasma mycoides subspecies mycoides.

A one-time, orally administered dose of greater than or equal to 1 X 10(6) colony-forming units of Mycoplasma mycoides subspecies mycoides was sufficient to induce clinical mycoplasmosis (n = 37) terminating in fatal mycoplasmemia in 73% (37 of 51) of the clinically affected kids. The pathogen was isolated from the blood samples as early as 24 hours after oral inoculation; hot, swollen joints frequently were evident by 4 or 5 days after exposure. Pyrexia (to 42.3 C) was detected in about 95% (35 of 37) clinically affected kids, although about 5% (2 of 35) died peracutely without fever or other premonitory signs. At necropsy, the cardinal lesions were a fibrinopurulent polyarthritis and red, patchy to diffuse areas of consolidation in 1 or more lung lobes. At death, usually within 4 to 16 days after oral inoculation, the concentration of M mycoides subspecies mycoides in the blood was 1 X 10(6) to 1 X 10(7) colony-forming units/ml. Histologically, the kids had diffuse fluid leakage into pulmonary alveoli and to a lesser extent into small vessels of various other organs. Fibrinocellular thrombi of terminal occurrence were occasionally present in various organs. The meningeal, pleural, and peritoneal surfaces had vascular leakage and a minimal perivascular accumulation of leukocytes. The disease was contagious. Of 14 noninoculated control kids in close confinement with affected kids, 8 (57%) developed mycoplasmosis in 7 to 15 days and died of mycoplasmemia. The remaining 5 noninoculated kids remained healthy, as did noninoculated kids that were kept isolated from affected kids.

Fecal shedding of Giardia duodenalis, Cryptosporidium parvum, Salmonella organisms, and Escherichia coli O157:H7 from llamas in California.

OBJECTIVE: To evaluate fecal shedding of Giardia duodenalis, Cryptosporidium parvum, Salmonella organisms, and Escherichia coli O157:H7 from llamas in California with respect to host factors and management practices. ANIMALS: 354 llamas from 33 facilities. PROCEDURE: Fecal specimens were collected and examined for G. duodenalis and C. parvum by means of immunofluorescent microscopy. Salmonella organisms were cultured by placing feces into selenite enrichment broth followed by selective media. Escherichia coli O157:H7 was cultured by use of modified tryptocase soy broth followed by sorbitol MacConkey agar, with suspect colonies confirmed by means of immunofluorescent microscopy. RESULTS: 12 of 354 fecal specimens (3.4%) had G. duodenalis cysts. Younger llamas (crias) were more likely to be shedding cysts, compared with older llamas. Farm-level factors that increased the risk of shedding were large numbers of yearlings on the property (> 10), smaller pen sizes, large numbers of crias born during the previous year (> 10), and large pen or pasture populations (> 20). None of the 354 fecal specimens had C. parvum oocysts. Seventy-six (from 7 facilities) and 192 (from 22 facilities) llamas were tested for Salmonella organisms and E. coli O157:H7, respectively. All fecal specimens had negative results for these bacteria. CONCLUSIONS AND CLINICAL RELEVANCE: Shedding of G. duodenalis was primarily limited to crias 1 to 4 months old. Llamas from properties with large numbers of crias born in the previous year, resulting in large numbers of yearlings in the current year, were at greater risk of infection. In addition, housing llamas in smaller pens or pastures and managing llamas and crias in large groups also increased the risk of G. duodenalis shedding.

Immunologic surface markers on nonhuman primate lymphocytes.

Peripheral blood lymphocytes from 37 healthy rhesus macaques (Macaca mulatta) and thymocytes from 10 fetal and neonatal rhesus macaques were studied for membrane characteristics. Spontaneous rosette formation with sheep erythrocytes, a characteristic of human T lymphocytes, was evaluated. The presence of membrane-bound immunoglobulin and surface receptors for fixed complement was measured, using fluorescent antibody techniques and erythrocyte-antibody-complement rosettes, respectively. The mean percentages +/- 1 standard error of the lymphocyte markers in the peripheral blood lymphocytes from the macaques were: spontaneous rosettes, 63 +/- 1.0; erythrocyte-antibody-complement rosettes, 14.9 +/- 1.2; and membrane immunoglobulin-positive cells, 21.9 +/- 2.2. These values are very similar to values reported for human beings.

Lymphocyte subpopulations in spontaneous disease of rhesus macaques.

The immunologic status of rhesus macaques (Macaca mulatta) with naturally occurring disease was evaluated by determining the percentages of B and T lymphocytes and mitogen responsiveness of lymphocytes in peripheral blood and lymph nodes. The B lymphocytes were identified by the presence of cell surface immunoglobulin and receptors for complement. The T lymphocytes were identified by their ability to form spontaneous rosettes with sheep red blood cells. Rhesus macaques with idiopathic or primary amyloidosis had normal lymphocyte characteristics. Peripheral blood lymphocytes from rhesus macaques with atypical tuberculosis had decreased percentages of spontaneous rosette-forming cells and depressed responses to concanavalin A, and those with chronic diarrhea or chronic arthritis were also found to have abnormal peripheral blood lymphocyte characteristics. The percentage of B and T lymphocytes in normal lymph nodes was variable, making simultaneous histologic examination necessary for evaluation of diseased animals.

Malignant lymphoma with B-lymphocyte characteristics in dogs.

Cell surface membrane characteristics of B and T lymphocytes were demonstrated on cells from canine malignant lymphoma, and the results were compared with cytologic classification. Lymphoma in 4 of 5 dogs was found to have one or more characteristics of B lymphocytes. Correlation between the cytologic classification and the presence of B- and T-lymphocyte characteristics was not apparent.

Feline malignant lymphomas: comparison of morphologic and immunologic characteristics.

Lymphoid cell populations from various hematopoietic tissues of normal cats (n = 22) and from cats with malignant lymphoma (n = 14 cats) were examined simultaneously for morphologic and immunologic features. Scanning electron microscopy and mitogen stimulation studies were not useful in identifying the B or T cell nature of malignant lymphomas. Cell markers successfully used to identify B cells were the presence of surface immunoglobulin by fluorescent-immunoglobulin staining procedures and the presence of complement receptors by EAC (erythrocyte, antibody, complement) rosette formation. The formation of rosettes with guinea pig erythrocytes was used to identify T cells. Using these cell surface markers, thymic lymphomas were found to be composed of T cells and alimentary lymphomas were found to be composed of B cells. The multicentric lymphomas lacked B or T cell surface markers. Classification by cytologic type of cell did not show any correlation with other values.

Rotavirus antibody assays on monkey sera: a comparison of enzyme immunoassay with neutralization and complement-fixation tests.

An enzyme immunoassay (EIA) for the detection of rotaviral antibodies was developed, using a purified, cell culture-grown SA 11 viral antigen and alkaline phosphatase as an enzyme label. This technique was evaluated by comparative testing with tube neutralization and complement-fixation assays on a collection of simian sera. There was close correlation between positive and negative results obtained by EIA and by neutralization. The EIA was as easy to perform as complement fixation testing, but showed greater sensitivity and fewer nonspecific reactions. Thus, EIA was shown to be a very suitable test for routine detection of rotaviral antibodies in serum. Results of neutralization tests suggested that the monkeys (mostly rhesus macaques) in the present study were infected with viruses varying in their antigenic relatedness to SA 11 virus and to a British isolate of calf rotavirus.

Histologic classification as a prognostic criterion for canine lymphosarcoma.

Neoplastic tissues from 72 dogs with lymphosarcoma were histologically classified according to the Rappaport schema to determine if the histologic features of the disease had any clinical or prognostic importance. Of 72 dogs, lymphosarcomas in 7 were classified as nodular (9.7%) and 65 were classified as diffuse (90.3%). The two principal cytologic types were lymphocytic, poorly differentiated, and histiocytic, which composed 39% and 56% of the lymphosarcomas, respectively; whereas lymphocytic, well differentiated, mixed, and undifferentiated composed 6%. Clinically, all of the dogs were stage III or IV, according to the accepted criteria for canine lymphosarcoma. The overall complete remission rate was 64% and was defined as no clinical evidence of disease after 9 weeks of chemotherapy. Median remission among nodular histiocytic, diffuse lymphocytic, poorly differentiated, and diffuse histiocytic (DH) groups of dogs was 42 days, 29 days, and 42 days (range, 0 to 1,095), respectively. Median survival for the same groups was 235 days, 190 days, and 173 days (range, 1 to 1,261), respectively. A logarithmic analysis of variance revealed no significant differences among nodular histiocytic, diffuse lymphocytic, poorly differentiated, and DH groups relative to days remission, as well as to days survival. It was observed that those dogs with neoplasms classified as DH had longer remission durations. It would appear that for any one animal, histologic classification according to the Rappaport schema cannot be used as a prognostic criterion in predicting therapeutic response, remission, or survival.

Immunologic abnormality in a group of Macaca arctoides with high mortality due to atypical mycobacterial and other disease processes.

Of 54 Macaca arctoides, 44 died during the 2.5 years after their assignment to a common cage. Although early deaths were due to trauma, acute gastric dilatation, and shigellosis; latter deaths were the result of a variety of uncommon diseases including atypical mycobacterial disease, malignant lymphoma, protozoan encephalomyelitis, and other necrotizing and inflammatory lesions. Atypical mycobacterial disease due to Mycobacterium avium intracellular serotypes was the most frequent single disease agent recognized (33% [18 macaques]). This disease began in the ileum and large intestine with subsequent systemic involvement. An abnormality of host response to infective agents, in general, was indicated by the unusually high occurrence of this disease, as well as other disease processes. Morphologic evaluation of lymphoid organs revealed decreased cellularity of follicles and decreased numbers of plasma cells in all macaques, whereas T cell-dependent areas varied from hypocellular to hypercellular with 5 macaques with malignant lymphoma. The spontaneous erythrocyte rosette-forming subpopulation of T cells was decreased in peripheral blood, but was increased in lymph nodes containing atypical mycobacterial lesions. Serum immunoglobulin value decreased progressively in diseased macaques. A basic abnormality of T-cell subpopulations controlling other components of host response was suspected. Macrophages from lesions that contain mycobacterial organisms did not phagocytize latex beads normally in vitro, whereas monocytes in the blood of the same macaques were capable of in vitro phagocytosis.

Cellular immunologic studies of malignant lymphoma in rhesus macaques.

Cells from malignant lymphoma in 10 rhesus macaques were examined for lymphocyte surface markers. Three had features of T cells, 5 had features of B cells, and 2 lacked evidence of either B- or T-cell differentiation. Correlation between the histologic classification of cell type and the B- or T-cell nature of the neoplasms was not evident. Evaluation of serum electrophoresis, mitogen responses tests, and previous histologic studies suggest that the development of the neoplastic lymphocyte proliferation occurred following or during an abnormal immunologic response.

Polyclonal gammopathies associated with chronic diseases in nonhuman primates.

Serum samples collected from clinically healthy rhesus macaques (Macaca mulatta) were compared with serums from animals diagnosed as having malignant lymphoma, atypical tuberculosis, progressive multifocal leukoencephalopathy, or more than 1 of these. Electrophoretic analyses of serum proteins (in grams per deciliter) indicated that mean values in a clinically normal group were as follows--total protein, 8.30; albumin, 4.07; alpha-globulin, 0.85; beta-globulin, 2.23; and gamma-globulin, 1.15. In macaques with malignant lymphoma, mean values were--total protein, 7.60; albumin, 2.72; alpha-globulin, 0.91; beta-globulin, 1.71; and gamma-globulin, 2.23. In macaques with atypical tuberculosis, these values were 8.47, 2.92, 0.84, 2.18, and 2.52, respectively, and those with progressive multifocal leukoencephalopathy, 9.06, 4.01, 6.71, 2.42, and 1.93. Where multiple serum samples were available from 1 macaque for analysis, gamma-globulin values were increased before clinical disease was apparent. Evaluation of serums from macaques may be used as a means of detecting preclinical lymphoproliferative disease.