Parvovirus-induced regression of canine transmissible venereal sarcoma

In 1981, during the worldwide canine parvovirus (PV) epizootic, canine transmissible venereal sarcomas growing in Beagles in a colony regressed earlier than expected after the dogs became infected with PV. Subsequent studies revealed that modified-live PV vaccine (feline panleukopenia virus) was capable of preventing tumor transplantation when the vaccine was inoculated simultaneously with the tumor in a site distant from the implantation site. However, the PV vaccine had no effect if it was inoculated 3 or 18 days after the tumor was transplanted.

Metastatic transmissible venereal sarcoma in a dog

An adult male dog with large penile sheath and serosanguineous exudate from the preputial orifice and a cutaneous fistula in the right inguinal area was examined. Necropsy revealed tumor masses on the penis and prepuce, in superficial inguinal and external iliac lymph nodes, and in the liver. Histopathologic diagnosis of the tumor was confirmed by transplantation studies.

Growth stage dependent expression of MHC antigens on the canine transmissible venereal sarcoma

Canine transmissible venereal sarcoma (CTVS) is a naturally occurring contagious neoplasm which can be transplanted with intact viable cells across major histocompatibility (MHC) barriers within the species and even to other members of the canine family, such as foxes, coyotes, and wolves. After 2 to 4 months of progressive growth the tumour regresses spontaneously in adults but metastasizes in immunosuppressed hosts and neonates. The mechanisms of how the tumour cells manage to overcome histocompatibility barriers so successfully for such a long period and yet succumb later are not known. In the present study we found that CTVS cells were not stimulatory to the lymphocytes of normal or tumour-bearing animals in mixed lymphocyte-tumour reaction (MLTR), although the lymphocytes from tumour-bearing animals in mixed lymphocyte-tumour reaction (MLTR), although the lymphocytes from tumour-bearing hosts responded well to either phytohaemagglutinin (PHA) or third-party allogeneic lymphocytes. Immunofluorescent antibody (IFA) assay of MHC antigens by monoclonal antibodies (MoAb) to monomorphic Class I and Class II MHC antigens showed that progressor tumour cells lacked the expression of the antigens whereas 30 to 40% of regressor tumour cells expressed them.

Separation and identification of bovine lymphocyte populations

Various methods for separation of lymphocyte populations have been modified and adapted for use in isolating and identifying bovine lymphocytes. Ficoll diatrizoate (F-D) with a specific density of 1.084 was found to be superior to those with densities of 1.080 and 1.077 which were developed originally for the mouse and human mononuclear cells, respectively. F-D with a density of 1.084 attained a lymphocyte (absolute number) recovery rate of 92% whereas those with densities of 1.080 and 1.077 yielded 81% and 71% recovery rate of lymphocytes, respectively. Subsequent separation of T lymphocytes was achieved best by nylon wool column whereas separation of B lymphocytes was attained best by complement-mediated depletion of T lymphocytes with the T lymphocyte specific monoclonal antibody (MAb), BLT-1. The former yielded 95 +/- 3% T lymphocytes with 47 +/- 9% recovery rate, and the latter gave 96 +/- 3% B lymphocytes with 71 +/- 9% recovery rate. In comparison, direct panning of F-D gradient separated mononuclear cells with goat anti-bovine IgG coated plates yielded 80% B lymphocytes with 31% recovery rate and indirect panning of MAb BLT-1 treated F-D gradient-separated mononuclear cells with goat anti-mouse IgG coated plates yielded 89% T lymphocytes with 35% recovery rate.

Non-gradient regional differences in tumor growth

Tumor cells inoculated subcutaneously into various regions of the trunk of dogs showed differences in growth for prolonged time periods. However, consistent antero-posterior gradient tumor growth patterns previously reported by other investigators in mouse tumor systems were not observed. The regional variance in tumor growth was not great enough to overcome the dose-response growth relationship in the dogs inoculated with doubling doses of tumor cells.

Canine cyclic hematopoiesis: alterations in T lymphocyte subpopulations in peripheral blood, lymph nodes, and thymus of gray collie dogs

Cyclic hematopoiesis (CH), also called cyclic neutropenia, is an inherited disorder known to occur in both humans and gray collie dogs. Previous reports have provided ample evidence to suggest that lymphocyte activity and regulatory mechanisms may be abnormal in CH. The present study examined the lymphocyte populations of several lymphoid compartments of gray collie dogs. The percentage of B lymphocytes in the lymph nodes of CH dogs was significantly increased whereas that of null lymphocytes was decreased. The percentage of T lymphocytes did not differ between CH and normal dogs, however, the proportions of T lymphocyte subpopulations were significantly different. The levels of T lymphocytes expressing IgGFc receptors (T gamma) in the thymus, lymph nodes, and peripheral blood were significantly increased; whereas the levels of T lymphocytes expressing IgMFc receptors (T mu) were significantly decreased. The percentage and absolute numbers of T gamma and T mu lymphocytes cycled in CH dogs. The percentage and absolute numbers of neutrophils were greatest when that of T gamma lymphocytes was reduced. The cycles of monocytes and T gamma lymphocytes occurred in close association and a linear relationship between the levels of these cells was observed both in terms of percentage (r = 0.62; P less than 0.01) and absolute number (r = 0.67; P less than 0.05). The percentage of T gamma and T mu lymphocytes were inversely correlated (r = -0.68; P less than 0.01).

H-Y antigen expression in heterogametic males (XY) and females (ZW): a factor in reproductive strategy?

The cells of heterogametic females with ZW sex chromosomes express H-Y or H-W antigen. A hypothesis is formulated to explain why these animals are capable of 'practicing' amphigonia retardata, i.e., delay in actual fertilization of eggs by retaining viable sperm within the oviduct for a considerable time (several months).

Production and characterization of a bovine T cell-specific monoclonal antibody identifying a mature differentiation antigen

A monoclonal antibody (MAb), BLT-1, with specificity for bovine mature T cells was prepared by somatic cell hybridization of myeloma NS-1 and spleen cells from BALB/c mice hyperimmunized with bovine T lymphocytes. The MAb reacted with over 92% of nylon wool-nonadherent lymphocytes (T cells) but not with nylon wool-adherent EAC-positive lymphocytes (B cells) in the indirect immunofluorescence assay. It is an IgM, with kappa-light chains, which fixed complement well and killed over 95% of mature T cells in complement-mediated cytotoxicity assays. It reacted with the same proportions of peripheral lymphoid cells (peripheral blood, lymph nodes, and spleen) as the polyclonal goat anti-bovine thymocyte serum (GABTS), but only with 25% of GABTS-positive thymocytes. Immunoperoxidase staining of frozen tissue sections showed that the BLT-1-positive cells were located in the medulla of the thymus and in the T lymphocyte areas of lymph nodes. Western immunoblotting assays showed that the BLT-1-reactive membrane antigen is a 22,000 m.w. protein which was inducible in bovine thymocytes with bovine thymic hormones, thymosin fraction 5, thymosin alpha 1, and thymopentin ORF-18150, indicating that it is a mature T lymphocyte differentiation antigen. The thymosin alpha 1 and thymopentin were found to show additive effects on mature T cell antigen expression by bovine thymocytes.

Production and characterization of a bovine T cell-specific monoclonal antibody identifying a mature differentiation antigen

A monoclonal antibody (MAb), BLT-1, with specificity for bovine mature T cells was prepared by somatic cell hybridization of myeloma NS-1 and spleen cells from BALB/c mice hyperimmunized with bovine T lymphocytes. The MAb reacted with over 92% of nylon wool-nonadherent lymphocytes (T cells) but not with nylon wool-adherent EAC-positive lymphocytes (B cells) in the indirect immunofluorescence assay. It is an IgM, with kappa-light chains, which fixed complement well and killed over 95% of mature T cells in complement-mediated cytotoxicity assays. It reacted with the same proportions of peripheral lymphoid cells (peripheral blood, lymph nodes, and spleen) as the polyclonal goat anti-bovine thymocyte serum (GABTS), but only with 25% of GABTS-positive thymocytes. Immunoperoxidase staining of frozen tissue sections showed that the BLT-1-positive cells were located in the medulla of the thymus and in the T lymphocyte areas of lymph nodes. Western immunoblotting assays showed that the BLT-1-reactive membrane antigen is a 22,000 m.w. protein which was inducible in bovine thymocytes with bovine thymic hormones, thymosin fraction 5, thymosin alpha 1, and thymopentin ORF-18150, indicating that it is a mature T lymphocyte differentiation antigen. The thymosin alpha 1 and thymopentin were found to show additive effects on mature T cell antigen expression by bovine thymocytes.

Effects of horse and fetal calf serum on the expression of tumor-associated antigen and tumorigenicity of L5178Y leukemia/lymphoma cells

A tumor antigen (TA) associated with murine leukemia-lymphoma L5178Y cells has been identified by the enzyme-linked immunosorbent assay (ELISA) and indirect immunofluorescence (IIF) techniques. The antigen was present in both non-solubilized and 0.5% NP-40 solubilized membrane extracts. Rabbit anti-L5178Y lymphoma serum (RALS), extensively absorbed with normal mouse tissues, identified TA in extracts of L5178Y lymphoma and L5178Y leukemia cells grown in horse serum (L5178Y/HS), but not in extracts of L5178Y cells grown in fetal calf serum (L5178Y/FCS). Similarly, absorbed rabbit anti-L5178Y/HS serum specifically reacted with extracts of lymphoma and L5178Y/HS but not with L5178Y/FCS cells. Membrane IIF showed positive reactivity in 88% of lymphoma and 73% of L5178Y/HS cells, whereas splenic lymphocytes and L5178Y/FCS cells were negative. Goat anti-AKR virus serum reacted with soluble extracts of lymphoma, L5178Y/HS, and L5178Y/FCS as well as with normal DBA/2 tissues in the ELISA. However, goat anti-AKR virus serum did not block the reactivity of RALS to lymphoma in the blocking ELISA (BELISA). Expression of TA, but not murine leukemia viral antigen(s), was correlated with the in-vivo tumorigenicity of the L5178Y cells. The antigenic activity of lymphoma extract was reduced by incubation for 1 h at 56 and 65 degrees C, by trypsin digestion, and by exposure to pH 2.8 or 11.0 for 1 h. The antigen, sequentially purified by gel filtration and Lentil-lectin affinity chromatography, was a glycoprotein, with a molecular weight of approx. 64,000 daltons, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis.

Immunoelectron microscopic localization of a tumor-associated antigen (TAA) in the canine transmissible venereal sarcoma by anti-TAA-antiferritin hybrid antibodies

Immunoferritin and immunoperoxidase reagents were used to localize a tumor-associated antigen (TAA) of the canine transmissible venereal sarcoma (CTVS). Round tumor cells from the CTVS at different stages of growth, i.e., progressive, steady state, and regressing, had TAA diffusely distributed throughout the cytoplasm. In general, TAA was not found on the plasma membrane, within the nucleus, between inner and outer membranes, in cytoplasmic vacuoles, or specifically with any part of the cytocavitary system. Transitional tumor cells, which are intermediate cell types between round cells and spindle-shaped cells and which appear in the tumors at steady state and regressing stages, contained less TAA in their cytoplasm than did the round cell type. The microvilli of tumor cells also contained TAA, suggesting that, in addition to whole cell lysis, shedding of all or parts of these processes may be a mechanism of TAA release as evidenced by the presence of antigenic activity in the extracellular material.

Detection of immune complexes in sera of dogs with canine transmissible venereal sarcoma (CTVS) by a conglutinin-binding assay

The canine transmissible venereal sarcoma (CTVS) is capable of extended growth in an allogeneic host. Since immune complexes can enhance allograft survival in other animal models, we used an enzyme-linked conglutinin-binding assay to determine the presence and amount of circulating immune complexes in dogs with CTVS. With the conglutinin-binding assay, 23 of 64 dogs (36 per cent) bearing CTVS had concentration of immune complexes 3 standard deviations greater than those detected in normal canine serum. When dogs with circulating immune complexes were separated into 3 groups based on whether the size of CTVS had increased (progressor), decreased (regressor) or remained the same (steady-state) during the week before collection of serum, no significant difference was found in the amounts of immune complexes in sera from progressor dogs. In 3 regressor dogs that received a second transplant of CTVS, the mean concentration of circulating immune complex was significantly greater than the mean for progressor dogs. In progressor dogs, amounts of immune complexes decreased with increasing tumour volume. Following sucrose density gradient ultracentrifugation analysis of sera from a normal and progressor dog, 27S complexes containing both IgG and IgM were detected in serum from a progressor dog. Thus, it appears that the conglutinin-binding assay is a useful and sensitive method for detecting immune complexes in canine serum.

Canine transmissible venereal sarcoma: quantitation of T-lymphocyte subpopulations during progressive growth and spontaneous tumor regression

The levels of T-lymphocyte subpopulations expressing IgMFc and IgGFc receptors (i.e., T mu lymphocytes and T gamma lymphocytes, respectively) were quantitated for T-lymphocytes obtained from peripheral blood, draining and nondraining lymph nodes, and the tumor mass during progressive growth and spontaneous regression of the canine transmissible venereal sarcoma. Analysis of the T-lymphocyte subpopulations in these lymphoid compartments demonstrated that distinct profiles of T mu and T gamma lymphocytes correlated respectively with the growth and regression statuses of the tumor. The percent of T gamma lymphocytes in the peripheral blood of dogs with progressing, steady-state, and late-regressing tumors was significantly increased over that of control dogs (P less than .05, P less than .001, and P less than .001, respectively) and over that of dogs with early-regressing tumors (P less than .05, P less than .01, and P less than .02, respectively). The percent of T gamma lymphocytes in the lymph nodes draining the tumor was observed to have a significant increase in dogs with progressing (P less than .01), steady-state (P less than .01), and late-regressing (P less than .001) tumors compared with that in control dogs. The percentage of T gamma lymphocytes was observed to have a significant increase in the nondraining lymph nodes of dogs with steady-state and late-regressing tumors compared with that of control dogs (P less than .01 and P less than .002, respectively) and that of dogs with progressing tumors (P less than .001 and P less than .0005, respectively). The percent of tumor-infiltrating T gamma lymphocytes was lowest in tumors that were growing progressively. A significant increase in T gamma lymphocytes was observed in steady-state (P less than .05), early-regressing (P less than .001), and late-regressing (P less than .05) tumors. Early-regressing tumors contained significantly (P less than .005) greater levels of T gamma lymphocytes than did late-regressing tumors.

The pineal body of the dog

A technique is described for finding the pineal body of the dog. The posterior half of the skull is cut a little behind the parietofrontal suture, through the occipital condyles. The cerebral hemispheres and cerebellum are carefully sliced, disclosing the pineal at the frontal edge of the colliculi. Two types of cells are present, those with completely round nuclei, and others with vesicular and variably shaped nuclei. In the histological pattern, ependymal cells were observed on the edges, pinealocytes and glial cells within the gland.

Role of cyclic AMP in antiserum-induced growth inhibition of murine leukemia L5178Y cells

Heat-inactivated rabbit antiserum, in the absence of complement, induced a 1.5-2-fold increase in cyclic AMP levels in target cells L5178Y leukemia lymphoblasts within 10-20 min after the experiment. This change preceded the previously reported delayed inhibitory effects of antiserum on cell growth such as inhibition of RNA, DNA, and protein synthesis and cell proliferation, suggesting that cyclic AMP may be one of the mediators of the antigen-antibody reactions which occur at the cell surface. Furthermore, the addition of cyclic GMP or excess calcium to either antiserum or cyclic AMP-treated cultures alleviated the growth inhibitory effects of either antiserum or cyclic AMP, substantiating further the hypothesis proposed.

Regulation of leukocyte glass adherence and tube leukocyte adherence inhibition (LAI) reactivity by serum factors in dogs with progressing or spontaneously regressing canine transmissible venereal sarcoma (CTVS)

We examined the regulation of leukocyte glass adherence and tube leukocyte adherence inhibition (LAI) reactivity by serum factors in dogs with regressing or progressing canine transmissible venereal sarcomas (CTVS). Both regressor and progressor peripheral blood leukocytes (PBL), draining and non-draining lymph node cells (LNC), and splenic leukocytes were significantly responsive to CTVS antigen extract in tube LAI. In contrast, a significant decrease in basal glass adherence of progressor PBL, draining and non-draining LNC, and splenic leukocytes was observed. Normal glass adherence was restored to progressor leukocytes by extensive washing with warm serum-free media, while significant tube LAI responsiveness to CTVS antigen extract was maintained. Preincubation of regressor PBL and LNC with progressor sera in two-stage tube LAI decreased the basal glass adherence of treated leukocytes. This effect of progressor sera was heat labile, a characteristic of CTVS antigen. Collectively, these findings suggest that progressor leukocytes and progressor sera treated regressor leukocytes were activated by interaction with serum CTVS antigen and thus behaved in tube LAI as stimulated cells, even in the absence of CTVS antigen. Regressor but not progressor sera were shown to contain anti-CTVS IgG with specific arming activity for normal dog PBL, but not LNC in two-stage tube LAI. The nonadherent response of peripheral blood neutrophils in two-stage tube LAI was proportional to the concentration of arming IgG, whereas no change was observed in glass adherence of PBL. The results of this study define the role of progressor and regressor serum factors in the mechanism of tube LAI and demonstrate a relationship between leukocyte glass adherence and the clinical course of CTVS. These findings show that tube LAI is a simple and reproducible measure of active factors in the immune response to a tumor.

Increase in the haemolytic complement activity of dogs affected with cyclic haematopoiesis

Cyclic haematopoiesis (CH) is an inherited disorder which occurs in both humans and Grey Collie dogs. The disease is characterized by fluctuations in the numbers of peripheral blood leucocytes, reticulocytes and platelets at regular intervals and is associated with a variety of clinical signs. The most prominent cycle observed is that of neutrophils. The 12-day neutropenic cycle includes a period of relatively normal neutrophil counts, a period of neutropenia and generally a period in which neutrophil counts greatly exceed the normal range. In this study the daily serum haemolytic complement activity (classical pathway CH50) of CH and normal Collie dogs was assayed. The serum CH50 of normal Collie dogs was relatively stable throughout the test period. In contrast, the serum CH50 of CH dogs fluctuated extensively and the mean serum CH50 of CH dogs during the neutropenic cycle greatly exceeded that of normal Collie dogs over the same test period. A close temporal relationship between the stage of the CH neutropenic cycle and the serum CH50 was observed. The mean serum CH50 during neutropenia was not significantly different from that observed when neutrophil counts were within normal range, both values being significantly higher than that of normal dogs. However, the mean serum CH50 during the period of neutrophil rebound was significantly (P less than 0.01) higher than that during the period of neutropenia or normal neutrophil counts. These data suggest that alterations in the production of complement components or regulatory proteins occur at regular intervals in CH dogs.

Amplification of lymph node cell tube leukocyte adherence inhibition (LAI) reactivity by leukocyte adherence inhibition factor (LAIF)

This investigation examines the immunologic basis for specific antigen-induced tube leukocyte adherence inhibition (LAI) reactivity of draining lymph node cells (LNC) from dogs with canine transmissible venereal sarcoma (CTVS). CTVS regressor LNC, macrophage-depleted LNC, and enriched T lymphocyte fractions, but not enriched B lymphocyte fractions, were specifically reactive to CTVS antigen extract in direct tube LAI. In addition, regressor LNC amplified tube LAI responses by generating supernatants with leukocyte adherence inhibition factor (LAIF) activity for normal dog indicator LNC and enriched peripheral blood mononuclear cells (PBMC) in an indirect tube LAI assay. However, macrophage-depleted LNC and enriched T lymphocyte fractions failed to generate supernatants with LAIF activity, suggesting that macrophage accessory cells play a central role in the amplification of tube LAI. Interestingly, CTVS regressor peripheral blood leukocytes (PBL) and PBMC, which were specifically reactive in direct tube LAI, also failed to generate supernatants with LAIF activity. These findings demonstrate a distinction between LAIF-mediated amplification and direct tube LAI reactivity, and suggest that leukocyte populations with differing cellular proportions and from different immunologic compartments may participate in tube LAI via different mechanisms.

Canine transmissible venereal sarcoma: tumor cell and infiltrating leukocyte ultrastructure at different growth stages

Electron microscopic study of the canine transmissible venereal sarcoma (N = 26) at different stages of growth showed that tumors in a progressive phase of growth (N = 12) were comprised mostly of large, round cells with prominent nuclei and nucleoli, a few spindle-shaped cells and collagen fibers, focal areas of necrosis, and lymphocyte infiltrates. Regressing tumors (N = 9) had the fewest viable round cells, greater numbers of infiltrating leukocytes, and were comprised almost entirely of connective tissue (collagen bundles) in the latest stages of regression. The infiltrating leukocytes consisted primarily of lymphocytes, some eosinophils, and neutrophils, but very few macrophages. Round-cell nuclei contained numerous perichromatin and interchromatin granules. Their cytoplasm often had annulate lamellae complexes and large deposits of glycogen. Loosely packed tumor cells had extensive proliferation and elongation of cytoplasmic extensions (filopodia). Evidence for cell-mediated tumor cell lysis was demonstrated by degenerative changes in tumor cells which were closely apposed to lymphocytes. Spindle-shaped cells in regressing tumors had intravacuolar collagen fragments, suggesting a possible degradative capacity by these cells.

Establishment of asparaginase- and guinea pig complement-resistant subline of murine lymphoblastic leukemia L5178y cells

Asparaginase-resistant subline L5178Y/Asp of murine lymphoblastic leukemia L5178Y cells was established from resistant clones isolated from soft agar cultures treated with Escherichia coli asparaginase. The L5178Y/Asp cells were found to be over 1000-fold more resistant to E. coli asparaginase, co-resistant to inhibitory effect of guinea pig serum (complement), more tumorigenic for syngeneic DBA/2 mice, and to grow much better (higher plating efficiency) in soft agar medium. With the use of the resistant subline in immunocytotoxicity-cytostasis test in the presence of guinea pig complement, we have been able to demonstrate the presence of tumor-associated antigen(s) on the L5178Y cells which is/are also demonstrable by enzyme-linked immunosorbent assay.

Morphologic changes following intraarticular inoculation of Mycoplasma bovis in calves

Intraarticular inoculation of Mycoplasma bovis into the joints of six-week-old calves caused severe arthritis in five inoculates and mild arthritis in a sixth. Intraarticular inoculation of killed M. bovis did not cause arthritis. Arthritic calves had fever, joint swelling, lameness, neutrophilia, and intercurrent pneumonia from which M. bovis could not be recovered. Gross lesions were massive fibrinosuppurative synovitis and tenosynovitis, erosion of cartilage, and its replacement by polypoid granulation tissue. Histologic lesions were extensive ulceration of synovial membranes, leukocytic infiltration of the subsynovium, congestion, hyperemia, and thrombosis of the subsynovial vessels. Cartilage erosion was accompanied by chronic osteomyelitis and formation of pannus tissue. The presence of thrombi and platelet aggregates suggests that the inflammatory process in the synovium may arise from the interaction of M. bovis with the vasculature and the coagulation process of the host.

Identification and quantitation of bovine T cell antigen with enzyme-linked immunosorbent assay (ELISA)

The enzyme-linked immunosorbent assay (ELISA) was used to identify and quantitate T cell antigen(s) in bovine thymocytes and peripheral blood T cells. The ELISA, employing non-ionic detergent-solubilized lymphocyte membranes as antigen, and goat anti-bovine thymocyte serum (GABTS) and horseradish peroxidase-conjugated rabbit anti-goat immunoglobulin (PORAG) as direct and indirect reactants, respectively, showed that thymocytes and peripheral blood T cells separated by erythrocyte-antibody-complement (EAC) rosetting technique had high concentrations of T cell antigen. In contrast, bone marrow cells and EAC-positive peripheral blood B cells had minimal T cell antigen. 92.0 +/- 3.5% of EAC-positive bovine lymphocytes were found to be B cells and 89.5 +/- 5.8% of EAC-negative lymphocytes T cells, as determined by SmIg and anti-T cell immunofluorescence (IF) techniques. In both IF and ELISA, pre-absorption of rabbit anti-goat IgG serum was needed to obviate cross-reactions with bovine B cells. A competitive ELISA developed for quantitating T cell antigens, showed that peripheral blood T cells contained only 46% of the antigen present in thymocytes.

Increase in the serum macrophage migration inhibitory activity and lysozyme in dogs affected with cyclic hematopoiesis

Cyclic neutropenia (CN) is an inherited disease known to occur in both humans and Gray Collie dogs. In dogs, the disease is characterized by a profound and cyclic decrease in circulating granulocytes at 12-day intervals. Other formed elements of the blood also show cyclic changes and thus the disease is also called cyclic hematopoiesis (CH). In this study, daily serum levels of lysozyme and a factor with macrophage migration inhibitory (MIF) activity were assayed. Both MIF activity and lysozyme levels were elevated more than 2-fold and fluctuated cyclically in CH dogs during the 12-day cycle: CH dogs CH 490 and CH 491, had 32.7 +/- 16.8% and 35.9 +/- 18.3% migration inhibitory activity, respectively, as compared to 15.1 +/- 1.4% in normal dog N 492; CH 490 and CH 491 had 78.7 +/- 43.7 units and 86.9 +/- 58.7 units of lysozyme, respectively, as compared to 33.4 +/- 1.7 units in N 492. The change of MIF activity tended to precede that of lysozyme activity in CH dogs. Furthermore, MIF levels and monocyte counts correlated significantly during the 12-day neutropenia cycle (CH 490, r = 0.677, P less than 0.001; CH 491, r = 0.583, P less than 0.01).

Effect of antiserum on leukemia L5178Y cells: [3H]thymidine incorporation does not reflect DNA synthesis

1. The total amount of DNA present in L5178Y cells treated with antiserum in the absence of complement was decreased whereas the rate of incorporation of [3H]thymidine into DNA during a 1 hr pulse was increased as compared with those of controls. 2. This increase in specific activity of [3H]thymidine in the DNA of antiserum-treated cells appeared to be due, at least in part, to an increase in thymidine kinase activity.

Canine transmissible venereal sarcoma: distribution of T and B lymphocytes in blood, draining lymph nodes and tumours at different stages of growth

The levels of T, B and null lymphocytes in the peripheral blood, draining lymph nodes, and tumour masses at different growth stages in dogs transplanted with canine transmissible venereal sarcoma (CTVS) were determined by immunofluorescence techniques. The tumours were classified at excision into "progressor", "steady state", and "regressor" stages of growth. The percentage of B cells in the lymphocytes infiltrating into the progressively growing tumours (n = 10, 37.3 +/- 7.4%) was significantly higher (P less than 0.025) than that in regressing tumours (n = 21, 26.1 +/- 1.9%). In contrast, the percentage of T cells in the lymphocytes infiltrating into the regressing tumours (n = 21, 61.2 +/- 2.6%) was significantly higher (P less than 0.005) than that in the progressively growing tumours (n = 10, 34.0 +/- 5.1%). The tumours at the steady-state growth stage (n = 9) had 50.8 +/- 5.7% infiltrating T-cells, which was significantly higher (P less than 0.005) than the progressors and lower (P less than 0.005) than the regressors. The percentage of null cells of progressors (n = 10, 26.0 +/- 6.9%) was significantly (P less than 0.025) higher than in regressors (n = 21, 13.5 +/- 2.9%). The draining lymph nodes of progressor dogs (n = 5) had significantly fewer (P less than 0.025) B cells (8.2 +/- 2.3%) than in normal (n = 5, 16.1 +/- 3.1%), regressors (n = 12, 19.1 +/- 1.7%) and steady-state dogs (n = 5, 15.8 +/- 2.6%). Although there was slight lymphopenia and fluctuation of null cells, no significant differences in T- and B-lymphocyte levels were noted in the peripheral blood of the tumour dogs (n = 44) studied.

Sequential changes in peripheral blood leukocyte adherence inhibition (LAI) reactivity during progressive growth and spontaneous regression of canine transmissible venereal sarcoma

Sequential changes in canine transmissible venereal sarcoma (CTVS) extract-induced leukocyte adherence inhibition (LAI) reactivity of peripheral blood leukocytes (PBL) were monitored in dogs from the time of tumor inoculation through progressive growth and spontaneous regression or surgical excision of CTVS. The time-course profiles of LAI reactivity of tumor dog PBL correlated with the clinical stage of tumor growth, substantiating our previous findings in a cross-sectional study. The kinetics of the time-course appearance of LAI reactivity observed and the demonstration of a rapid anamnestic response following tumor challenge indicate further that LAI is a reliable in vitro measure of in vivo tumor immunity. A significant increase in CTVS antigen extract-induced LAI reactivity observed in the PBL during tumor regression suggest that LAI reflects a function effector cell mechanism associated with spontaneous regression of CTVS. By contrast, absence of significant LAI reactivity of PBL during progressive tumor growth suggests the presence of serum blocking factors. In addition a substantial rebound in LAI reactivity observed in the PBL of dogs 3 to 7 days following surgical excision of progressively growing CTVS provides further evidence that tumor-cell components are associated with progressive tumor growth and diminished LAI reactivity.

Autorosette formation of erythrocytes on peripheral blood mononuclear cells in dogs vaccinated with canine distemper live-virus vaccine

A time course study of the peripheral blood leukocytes of dogs vaccinated with canine distemper live virus (a paramyxovirus) vaccines showed that autorosette-forming leukocytes appeared from day 3 to day 10 after vaccination. The number of these cells peaked at day 7 when as many as 35% of mononuclear cells formed rosettes with autologous erythrocytes. In contrast, in nonvaccinated dogs, only 0.6 +/- 0.3% (standard error of the mean) of mononuclear cells formed rosettes throughout the 2-week period.

Identification of bovine T- and B-lymphocyte subpopulations by immunofluorescence surface marker analysis

A T-cell specific goat anti-bovine thymocyte antiserum was prepared for use in identifying T lymphocytes by an indirect fluorescent antibody (FA) technique. The antiserum was made specific for T lymphocytes through adsorptions with normal bovine RBC, normal serum, and bone marrow cells. It reacted with more than 95% of the thymocytes and less than 5% of the bone marrow cells. By the indirect FA assay, 72.9 +/- 5.7% (SD) of the peripheral blood lymphocytes of adult cows (n = 19) were identified as T lymphocytes. With the previously reported total B-lymphocyte number of 26.9 +/- 4.4%, as determined by a mixture of antiimmunoglobulin (Ig)G, anti-IgA, and anti-IgM, the 2 assays, in conjunction, can thus identify over 95% of the peripheral blood lymphocytes as either T or B lymphocytes. With the use of individual Ig class- and subclass-specific antisera in the direct FA assay, the peripheral blood lymphocytes of adult cows (n = 15) were shown to consist of 8.5 +/- 3.1% IgG1-bearing lymphocytes, 3.5 +/- 2.2% IgG2-bearing lymphocytes, 7.0 +/- 2.4% IgA-bearing lymphocytes, and 13.4 +/- 2.6% IgM-bearing lymphocytes--indicating that although the majority of B lymphocytes possess IgM on their surface, in cattle ther are many B lymphocytes without surface membrane (Sm)IgM, but with only SmIgG1, SmIgG2, or SmIgA.

Identification and physicochemical characterization of a tumor-associated antigen from canine transmissible venereal sarcoma

A tumor antigen associated wtih canine transmissible venereal sarcoma (CTVS) has been identified and partially characterized. The antigen was demonstrated in 3-M KCI and saline extracts of washed CTVS cells. Rabbit anti-CTVS antisera absorbed wih glutaraldehyde cross-linked normal dog serum and pooled homogenates of canine spleen, thymus, lymph node, and liver were used to identify the antigen. The specificity of the rabbit anti-CTVS antiserum for the CTVS antigen was established by use of immunodiffusion, two-dimensional electrophoresis, and the enzyme-linked immunosorbent assay (ELISA). Extracted CTVS antigen was fractionated by Sephadex G-200 chromatography, and the antigen factions were identified with the use of absorbed rabbit anti-CTVS antiserum and the ELISA technique. Antigen activity was detected in samples with estimated molecular weights greater than 70,000 daltons. Antigen fractions reacted with absorbed anit-CTVS antiserum to form a single precipitation band in immunodiffusion studies. Extraction of CTVS antigen with 3 M KCl and saline in the presence of a protease inhibitor did not significantly alter the antigen activity or molecular weight of the CVTS antigen. Cytoplasmic and nucleolar fluorescence were observed in an indirect immunofluorescence test with the use of acetone-fixed CTVS cells and absorbed anti-CTVS antiserum. The CTVs antigen activity was greatly reduced by trypsin digestion, by incubation for 1 hour at 65 degrees C, and by exposure to pH 2.8, 4.0, and 11.0 for 1 hour each.

Canine transmissible venereal sarcoma: leukocyte adherence inhibition (LAI) reactivity of various lymphoid tissues of dogs with tumors at different stages of growth

Leukocyte adherence inhibition (LAI) reactivity of various lymphoid tissues of dogs with canine transmissible venereal sarcoma (CTVS) at different stages of growth was determined by the tube LAI test. Tumors were classified at the time of excision into progressor, steady state, and regressor stages of growth. The LAI reactivity to CTVS antigen extract of spleen, draining and non-draining lymph-node cells, and peripheral blood leukocytes of regressors (non-adherence index--NAI of 172.8 +/- 46.8, 148.1 +/- 64.7, 138.7 +/- 47.3, and 172.2 +/- 60.7, respectively) was significantly greater than that of progressors (46.1 +/- 20.0, 38.5 +/- 21.5, 50.2 +/- 30.0, 24,6 +/- 37.2, respectively, p less than 0.001) and normal dogs (47.5 +/- 22.8, 54.6 +/- 24.6, 26.7 +/- 14.0, 50.9 +/- 22.4, respectively, p less than 0.001). In contrast, LAI reactivity of progressor lymphoid tissues to CTVS antigen extract did not differ significantly from that of normal dogs. LAI reactivity of lymphoid tissues from steady state tumor bearers (97.9 +/- 39.2, 80.7 +/- 47.3, 87.1 +/- 40.0, 85.1 +/- 53,9, respectively) was intermediate between and significantly different from LAI reactivities of regressor (p less than 0.05) and progressor (p less than 0.01) lymphoid tissues. Significant LAI reactivity observed in regressors suggests the presence of a functional effector cell mechanism associated with spontaneous regression of CTVS. The three distinct patterns of LAI reactivity observed in tumor-bearing dogs appear to correlate with the clinical course of tumor growth.

Identification of canine lymphocyte populations by immunofluorescence surface marker analysis

A T-cell-specific rabbit anti-dog thymocyte antiserum was prepared and used in an indirect fluorescent antibody technique to identify T lymphocytes. The antiserum was rendered specific by absorptions with normal dog red blood cells, lyophilized serum, and bone marrow cells. By the indirect immunofluorescence assay, 73.6 +/- 1.2 (SEM)% of the peripheral blood lymphocytes were identified as T lymphocytes. By direct immunofluorescence assay of surface membrane immunoglobulin-positive lymphocytes, 18.2 +/- 0.8% of the peripheral blood lymphocytes were identified as B lymphocytes. The two assays used in conjunction can thus identify over 90% of the peripheral blood lymphocytes as either T or B lymphocytes, with the remaining 8.2 +/- 1.0% as null cells.

T and B lymphocyte levels in the peripheral blood of dogs affected with cyclic neutropenia

Canine cyclic neutropenia (CN), a heritable disease of Collie dogs, is characterized by the periodic cycling of formed elements of blood and the near disappearance of neutrophils every 11-12 days. Studies suggest that lymphocyte activity and regulatory mechanisms may be abnormal in CN. In this study, an immunofluorescence in the peripheral blood of normal CN Collies. Normal Collie dogs (N = 10) had 73.0 +/- 2.4% T-lymphocytes, whereas CN dogs (N = 4) had only 63.2 +/- 1.9% similar cells among peripheral blood lymphocytes (P less than 0.005). Studies on B-lymphocytes showed that normal Collie dogs (N = 10) had 17.8 +/- 2.0%, whereas CN dogs (N = 4) had 29.6 +/- 3.3% B-lymphocytes (P less than 0.005). Absolute counts for B-lymphocyte levels for 2 CN Collie dogs (N = 10) had 17.8 +/- 2.0%, whereas CN dogs (N = 4) had 29.6 +/- 3.3% B-lymphocytes (P less than 0.005). Absolute counts for B-lymphocytes were also increased in CN dogs. In a related study, daily changes in T- and B-lymphocyte levels for 2 CN Collies and 1 age-and-sex matched normal Collie were monitored over the course of a 2-week hematopoietic cycle. Similar differences in peripheral blood T- and B-lymphocyte levels, as mentioned above, were found between the CN Collies and the normal Collie. The absolute B-lymphocyte counts for CN Collies also showed a statistically significant increase (P less than 0.005) over counts for the normal Collie, and daily changes in both B- and T-lymphocyte counts were always greater for CN Collies than for normal Collies.

Inhibition of calcium and glucose uptake by murine leukemia L5178Y cells treated with antiserum

Studies were performed to determine whether decreases in transport of calcium and glucose might be among the earliest changes triggered by the antigen-antibody reactions occurring on the cell surface of murine leukemia L5178Y cells after treatment with rabbit antisera. After treatment with antisera, in the absence of complement, these cells exhibited a decreased uptake of 45Ca, 2-deoxy[3H]glucose, and 3-0-methyl[3H]glucose. These changes occurred rapidly, within 2 minutes after the addition of antiserum, in contrast to the previously reported inhibitory effects of antiserum on DNA, RNA, and protein synthesis, which became demonstrable only after 4 to 8 hours. The kinetics of uptake of the radioactive substrates was biphasic, with a very rapid initial uptake followed by less rapid linear uptake. The precise mechanism of cell growth inhibition remains to be elucidated, but one of the initial effects of antiserum treatment may be a perturbation at the cell membrane such that transport of specific nutrients is decreased, resulting in the observed effects on macromolecular synthesis.

Karyotype analysis of leukocytes of gray collie (cyclic neutropenia)-normal bone marrow transplant chimeras six years after transplantation

Karyotype analysis was made on the leukocytes of 2 gray Collie (cyclic neutropenia)-normal bone marrow transplant chimeras transplanted 6 years previously to correct cyclic neutropenia of the gray Collie syndrome. In a male-to-female transplant chimera, all of the to metaphase spreads showed the karyotype of male donor origin. In this and the male-to-male chimera, the morphology of all chromosomes examined showed no gross anomalies or breaks which might be of recipient origin.

Depression of B-lymphocyte levels in the peripheral blood of cows with mastitis

The levels of B-lymphocytes in the peripheral blood of normal and mastitic cows were evaluated by fluorescent-antibody and erythrocyte-antibody-complement-rosetting techniques. Normal cows (N = 8) had 26.9 +/- 4.4% surface membrane immunoglobulin-positive lymphocytes, whereas mastitic cows (N = 6) had only 16.3 +/- 3.6% similar cells among lymphocyte preparations purified by the Ficoll-Paque density gradient separation and carbonyl iron phagocytosis methods. Studies on smiliar lymphocyte preparations by erythrocyte-antibody-complement-rosetting techniques showed that normal cows (N = 12) had 33.5 +/- 7.1% erythrocyte-antibody-complement-rosetting lymphocytes, whereas mastitic cows (N = 6) had 20.5 +/- 6.0% similar cells.

Adaptation of enzyme-linked immunosorbent assay to the avian system

A microplate enzyme-linked immunosorbent assay was developed to detect chicken anti-rovirus antibodies. Studies of the parameters which affect the outcome of the assay with avian serum revealed two aspects for a successful assay. First, enzyme-antibody conjugates prepared by the periodate oxidation technique were found to have retained far more immunological activity than conjugates produced by a glutaraldehyde cross-linking. Second, the results indicated an unusually high affinity of chicken immunoglobulin for the microplate plastic which was mostly eliminated by a pretreatment technique with fixed fetal calf serum. The enzyme-linked immunosorbent assay compared favorably with the latex passive agglutination test, yielding a titration endpoint of 1:511,000, or approximately 1,300 times more sensitive than the latex passive agglutination assay. The assay proved not only to be sensitive to less than 1 ng of specific antibody, but also to have low to moderate variance and high reliability.

Acid alpha-naphthyl acetate esterase: presence of activity in bovine and human T and B lymphocytes

Non-specific acid alpha-naphthyl acetate esterase (ANAE) activity was demonstrated in a majority of bovine peripheral blood lymphocytes, confirming and extending the observations on murine and human lymphocytes made by previous workers. Simultaneous study of both ANAE activity and spontaneous erythrocyte (E) or erythrocyte-antibody-complement (EAC) rosetting capability of the same bovine lymphocytes showed directly that, while 64.2 +/- 4.6 (SEM) % of bovine lymphocytes capable of forming E rosettes were ANAE positive, 38.3 +/- 0.8% of those forming EAC rosettes were also ANAE positive. Similar studies of human peripheral blood lymphocytes showed also that, while 80.6 +/- 2.2% of the lymphocytes capable of forming E rosettes were ANAE positive, 44.1 +/- 2.6% of EAC forming lymphocytes were ANAE positive. Thus the presence of ANAE activity in a majority of T lymphocytes and a significant proportion of B lymphocytes of both human and bovine peripheral blood is indicated. Human and bovine lymphocytes from phytohaemagglutinin (PHA)-stimulated cultures demonstrated greatly enhanced intensity of ANAE activity.

Elevated autorosette formation by lymphocytes of dogs affectd with cyclic neutropenia (CN)

Cyclic neutropenia (CN) is an inherited disorder characterized by regularly recurring episodes of neutropenia in humans and Gray Collie dogs. Early thymic hypotrophy and lymphoid exhaustion in the CN dogs suggests there may be a lymphoid cell differentiation defect. Later manifestations of CN in dogs include arthritis, anaemia, glomerulone-phritis, and amyloidosis which are often associated with autoimmune diseases. Several Coombs' antiglobulin tests were performed and did not detect autoantibodies, however, peripheral blood lymphocytes from CN dogs formed rosettes with their own erythrocytes while in normal dogs such rosettes were extremely rare. Furthermore, when lymphocytes from CN dogs were rosetted with erythrocytes from normal dogs, the numbers of allogeneic rosettes were comparable to those formed with autologous erythrocytes. These results suggest strongly that the rosetting lymphocytes are specific for common erythrocyte surface components. Although the physiological importance of the autorosetting phenomenon is not known, the frequency of autorosette formation in CN dogs, as reported here, suggests that it may be an early indication of developing autoimmune activity.

An enzyme-linked immunosorbent assay (ELISA) for detecting chicken anti-reovirus antibody at high sensitivity

An enzyme-linked immunosorbent assay (ELISA) with high sensitivity was developed for use in the avian system. Anti-reovirus antibody produced in chickens against the isolants S1133, UMI-203, Reo-25, and Winterfield were detected with this method at high titers (up to 1:14,000).

Lymphocyte response to phytohemagglutinin: temporal variation in normal dogs

The lymphocyte response to mitogens is frequently used as a screening method for monitoring general immunocompetence. In practice, however, the technique is potentially misleading. The results presented here suggest that temporal variation in lymphocyte response is the norm. Considerable variation in response to phytohemagglutinin was found for several dogs tested over different time periods. The response for any individual dog also fluctuated whether testing was at 2-week intervals, daily, or even every 4 h. This temporal variation remained whether separated lymphocytes or whole blood was cultured and when the results were expressed on a per lymphocyte basis. This suggests that there is a real difference in the response capability of individual lymphocytes. Factors affecting the numbers of leukocytes and the proportions of different types of lymphocytes in the peripheral blood are suggested as a possible source of the variation. Because of the inherent variation in lymphocyte responsiveness, it is necessary to test at different intervals to obtain an accurate indication of the general status of an individual's immunocompetence and to determine the time of peak response capability for that individual.

Recovery of hair coat color in Gray Collie (cyclic neutropenia)-normal bone marrow transplant chimeras

Gray Collie-normal bone marrow transplantation chimeras showed normal coloration of the hair coat on tails and several other areas 2 years after successful transplantation of bone marrow to correct cyclic neutropenia of the Gray Collie syndrome.