@article{pinelli_gebhard_mommaas_hoeij_langermans_ruitenberg_rutten_2000, title={Infection of a canine macrophage cell line with Leishmania infantum: determination of nitric oxide production and anti-leishmanial activity}, volume={92}, ISSN={["0304-4017"]}, DOI={10.1016/S0304-4017(00)00312-5}, abstractNote={We have previously shown that resistance to Leishmania infantum in dogs is associated with a Th1 type of immune response. In this study, we use a canine macrophage cell line (030-D) that can readily be infected with this protozoan parasite. Our aim is to further characterize the effector mechanisms involved in killing of Leishmania parasite in dogs. We observed that activation of 030-D cells by incubation with a supernatant derived from a Leishmania-specific T cell line containing IFN-gamma, TNF-alpha and interleukin-2 (IL-2) resulted in enhanced nitric oxide (NO) production by these cells. In addition, we observed enhanced anti-leishmanial activity of infected 030-cells after activation. Both, NO production and anti-leishmanial activity were abrogated by addition of L-N(G)-nitroargininemethyl ester (L-NAME), an analogue of L-arginine. Thus, NO play an important role in the anti-leishmanial activity of these canine macrophages. We propose the infection of the 030-D cell line as a good in vitro model to further investigate parasite-host cell interactions in dogs, a natural host of Leishmania parasites.}, number={3}, journal={VETERINARY PARASITOLOGY}, author={Pinelli, E and Gebhard, D and Mommaas, AM and Hoeij, M and Langermans, JAM and Ruitenberg, EJ and Rutten, VPMG}, year={2000}, month={Oct}, pages={181–189} }
 @article{gebhard_dow_childers_alvelo_tompkins_tompkins_1999, title={Progressive expansion of an L-selectin-negative CD8 cell with anti-feline immunodeficiency virus (FIV) suppressor function in the circulation of FIV-infected cats}, volume={180}, ISSN={["0022-1899"]}, DOI={10.1086/315089}, abstractNote={The acute stage of feline immunodeficiency virus (FIV) infection is characterized by the appearance of a major CD8 subpopulation with reduced expression of the CD8 beta chain (CD8alpha+betalo). CD8 antiviral activity was subsequently shown to be mediated by the CD8alpha+betalo phenotype, which is the dominant CD8 phenotype in long-term infected cats. Two- and three-color flow cytometric analysis demonstrated that the CD8alpha+betalo subset is L-selectin negative (CD62L-) and has increased expression of CD44, CD49d, and CD18, consistent with an activation phenotype. The CD8alpha+betaloCD62L- cells but not the CD8alpha+betahiCD62L+ cells demonstrated strong antiviral activity in the FIV acute-infection assay. The progressive expansion of the CD8alpha+betaloCD62L- effector subset cells in FIV-infected cats parallels that seen in human immunodeficiency virus (HIV)-infected patients, suggesting that failure in homeostatic mechanisms regulating lymphocyte activation or trafficking (or both) may be a consequence of both HIV and FIV infections.}, number={5}, journal={JOURNAL OF INFECTIOUS DISEASES}, author={Gebhard, DH and Dow, JL and Childers, TA and Alvelo, JI and Tompkins, MB and Tompkins, WAF}, year={1999}, month={Nov}, pages={1503–1513} }
 @article{bucci_gebhard_childers_english_tompkins_tompkins_1998, title={The CD8(+) cell phenotype mediating antiviral activity in feline immunodeficiency virus-infected cats is characterized by reduced surface expression of the CD8 beta chain}, volume={178}, ISSN={["0022-1899"]}, DOI={10.1086/515699}, abstractNote={The acute stage of feline immunodeficiency virus (FIV) infection is characterized by a CD8+ anti-FIV response that parallels the appearance of a CD8+ subpopulation with reduced expression of the beta chain (CD8 alpha + beta lo). The relationship between the CD8 alpha + beta lo phenotype and CD8+ anti-FIV activity was examined. Flow cytometric analysis of peripheral blood mononuclear cells with anti-CD8 beta chain monoclonal antibody 117 revealed that the CD8 alpha + beta lo phenotype expanded throughout the asymptomatic infection, constituting 80%-90% of the CD8 beta + cells in long-term-infected cats. Purified CD8 alpha + beta hi and CD8 alpha + beta lo subpopulations were analyzed for anti-FIV activity in an acute infection assay. Anti-FIV activity resided principally in the CD8 alpha + beta lo population and was demonstrated in acute FIV infections, as well as in long-term asymptomatic infections. These data suggest that a unique CD8 alpha + beta lo anti-FIV phenotype arises early in infection and may play a major role in eliminating virus and maintaining the asymptomatic infection.}, number={4}, journal={JOURNAL OF INFECTIOUS DISEASES}, author={Bucci, JG and Gebhard, DH and Childers, TA and English, RV and Tompkins, MB and Tompkins, WAF}, year={1998}, month={Oct}, pages={968–977} }
 @article{hammerberg_bevier_deboer_olivry_orton_gebhard_vaden_1997, title={Auto IgG anti-IgE and IgG x IgE immune complex presence and effects on ELISA-based quantitation of IgE in canine atopic dermatitis, demodectic acariasis and helminthiasis.}, volume={60}, ISSN={["1873-2534"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0031565919&partnerID=MN8TOARS}, DOI={10.1016/S0165-2427(97)00119-0}, abstractNote={Atopic dermatitis is a common allergic disease manifestation in dogs; however, there is no correlation between clinical disease and detectable total serum IgE. Auto antibodies of the IgG subclass against IgE may affect the detection of serum IgE by immunoassay and may be important in the regulation of IgE production by B cells. ELISA were developed to detect serum antibodies specific for IgE using a newly available canine monoclonal IgE of known antigen specificity, generated from a canine × murine heterohybridoma. To test for correlation of auto IgG anti-IgE levels with manifestation of atopic dermatitis, the sera from 101 atopic dogs were compared with sera from non-atopic dogs of various breeds, foxhounds manifesting clinical signs of demodectic acariasis and helminth parasitized random bred dogs for quantities of IgG anti-IgE measured in units/ml compared to a high titer standard serum. To test for serum effects on quantitation of IgE, known amounts of canine monoclonal IgE were added to various sera and measured by capture ELISA with detecting monoclonal antibodies specific for heat labile or heat stabile epitopes. Unheated sera from dogs manifesting clinical atopic dermatitis and helminth parasitized dogs had levels of IgG anti-IgE that were significantly lower than various breeds of dogs not manifesting dermatologic lesions and foxhounds manifesting demodectic acariasis. Heating sera at 56°C for 3 h to denature the high affinity binding site on the IgE heavy chain caused a marked increase over non-heated sera in detectable IgG angi-IgE in almost all dogs. This increase was most profound in helminth-infected dogs and foxhounds manifesting demodectic mange with 7 fold increases each, respectively, and in atopic dogs with a 5 fold increase compared to 3 fold increases for clinically-normal springer spaniels and all soft coated wheaten terriers. The terriers demonstrated an association of lower heated serum values of IgG anti-IgE with manifestation of a familial syndrome of protein-losing enteropathy and protein-losing nephropathy. The ability of mouse anti-canine IgE monoclonal antibodies specific for either heat labile or heat stabile epitopes to detect canine monoclonal IgE added to sera in known amounts varied from serum to serum and at different concentrations of the same serum, but did not correlate with IgG anti-IgE values for these sera. The range of absolute levels of serum IgE in dogs showing little or no inhibition of detection of added IgE was < 0.5 ng/ml to 2 μg/ml. It was concluded that the increase in detectable IgG anti-IgE after heating sera indicates that IgG × IgE immune complexes are normally present in most dogs; however, the increase over uncomplexed IgG anti-IgE was most pronounced in dogs manifesting atopic dermatitis and demodectic acariasis. A quantitative comparison of IgG anti-IgE or IgG × IgE to total serum IgE was not made because the ability of monoclonal antibodies specific for either heat labile or heat stable epitopes on the IgE heavy chain to detect IgE added to serum, as well as innate serum IgE, was highly variable in different dilutions of serum from individual to individual.}, number={1-2}, journal={VETERINARY IMMUNOLOGY AND IMMUNOPATHOLOGY}, author={Hammerberg, B and Bevier, D and DeBoer, DJ and Olivry, T and Orton, SM and Gebhard, D and Vaden, SL}, year={1997}, month={Dec}, pages={33–46} }
 @article{ruslander_gebhard_tompkins_grindem_page_1997, title={Immunophenotypic characterization of canine lymphoproliferative disorders}, volume={11}, number={2}, journal={In Vivo (Athens, Greece)}, author={Ruslander, D. A. and Gebhard, D. H. and Tompkins, M. B. and Grindem, C. B. and Page, R. L.}, year={1997}, pages={169–172} }
 @inproceedings{degernes_crosier_harrison_smith_dennis_gebhard_1997, title={Investigation of homologous and heterologous avian blood transfusions}, booktitle={Proceedings Annual Conference of the Association of Avian Veterinarians}, author={Degernes, L. A. and Crosier, M. and Harrison, L. D. and Smith, D. W. and Dennis, P. and Gebhard, D.}, year={1997}, pages={227–278} }
 @article{gebhard_orton_edmiston_nakagaki_deboer_hammerberg_1995, title={Canine IgE monoclonal antibody specific for a filarial antigen: Production by a canine x murine heterohybridoma using B cells from a clinically affected lymph node}, volume={85}, number={3}, journal={Immunology (Oxford, England)}, author={Gebhard, D. and Orton, S. and Edmiston, D. and Nakagaki, K. and Deboer, D. and Hammerberg, B.}, year={1995}, pages={429} }
 @article{gebhard_carter_1992, title={IDENTIFICATION OF CANINE LYMPHOCYTE-T SUBSETS WITH MONOCLONAL-ANTIBODIES}, volume={33}, ISSN={["0165-2427"]}, DOI={10.1016/0165-2427(92)90181-O}, abstractNote={A panel of five murine monoclonal antibodies to canine T-lymphocytes were produced. Antibodies 4.78, 12.125 and 8.358 reacted with approximately 18%, 39% and 60% peripheral blood lymphocytes, respectively. Two color flow cytometric analysis showed that lymphocytes expressing 1.140, 4.78, 8.53 and 12.125 were subsets of lymphocytes expressing 8.358. The lymphocytes expressing 8.358 were negative for surface immunoglobulin. The subsets defined by 1.140, 4.78 or 8.53, 12.125 were mutually exclusive and together account for most cells expressing 8.358 in the peripheral blood, spleen, and lymph node. In the thymus, approximately 47% cells were positive for both 1.140/4.78 and 8.53/12.125. SDS-PAGE analysis of radiolabelled thymus cell lysates demonstrated that antibodies 1.140 and 4.78 immunoprecipitated a 32,35 kd heterodimer under reducing conditions and 12.125 immunoprecipitated a single 56 kd chain under reducing and non-reducing conditions. Antibodies 8.53/12.125 and 1.140/4.78 react with canine lymphocyte populations that occur in proportions similar to lymphocytes expressing CD4 and CD8 like molecules in several primate and non-primate species. The molecules recognized by 12.125 and 1.140/4.78 were similar in size and subunit composition to human CD4 and CD8.}, number={3}, journal={VETERINARY IMMUNOLOGY AND IMMUNOPATHOLOGY}, author={GEBHARD, DH and CARTER, PB}, year={1992}, month={Aug}, pages={187–199} }