Humoral and Cellular Immune Responses in Turkey Poults Infected with Turkey Coronavirus

Abstract The objective of the present study was to elucidate the kinetics of humoral and cellular immune responses of turkey poults infected with turkey coronavirus (TCV). Turkey poults were orally inoculated with TCV at 10 d of age, and the immune responses were analyzed at 1, 3, 7, 14, 21, 28, 42, and 63 d postinfection (PI) in three different experiments. Total Ig to TCV was initially detected at 7 and 14 d PI in Experiments 1 and 3. In addition, Ig gradually increased from 7 to 21 d PI and remained at 80 immunofluroescent antibody assay (IFA) titers or more thereafter. Lymphocyte proliferation responses of spleen cells to concanavalin A were higher in TCV-infected turkeys than in noninfected control turkeys with significant differences (P < 0.05) being noted at 14 and 63 d PI in Experiment 2 and at 3 and 28 d PI in Experiment 3. Strong IFA staining response to TCV antigen was observed in intestines of turkeys at 1, 3, and 7 d PI, and the response declined from 14 to 28 d PI in Experiment 3. In Experiment 3, the IgG isotype antibody response to TCV was markedly increased after 21 d PI and remained high until 63 d PI. The IgM isotype antibody response to TCV was 1.40 and 0.91 at 7 and 14 d PI, respectively. The IgA isotype antibody response to TCV was very low as detected at 7 (0.13), 14 (0.20), and 21 (0.17) d PI. Turkeys infected with TCV had significantly higher (P < 0.05) antibody response to sheep erythrocytes than noninfected controls at 7 d PI. Virus-specific lymphocyte proliferation response of spleen cells was significantly stimulated (P < 0.05) at 63 d PI in Experiment 3. The proportion of the CD4+ subpopulation of T lymphocytes was significantly increased (P < 0.05) at 1, 7, and 21 d PI in Experiment 3. The results indicate that humoral and cellular immunities to TCV are elicited in turkeys following infection with TCV.

[1]  H. L. Thacker,et al.  Detection of antibody to turkey coronavirus by antibody-capture enzyme-linked immunosorbent assay utilizing infectious bronchitis virus antigen. , 2000, Avian diseases.

[2]  G. B. Havenstein,et al.  Alterations in the lymphocytic and mononuclear phagocytic systems of turkey poults associated with exposure to poult enteritis and mortality syndrome. , 1998, Avian diseases.

[3]  R. Ahmed,et al.  Humoral immunity due to long-lived plasma cells. , 1998, Immunity.

[4]  Richard C. Jones,et al.  Infectious bronchitis virus: immunopathogenesis of infection in the chicken , 2007, Avian pathology : journal of the W.V.P.A.

[5]  F. Haesebrouck,et al.  Monoclonal and polyclonal antibodies to chicken immunoglobulin isotypes specifically detect turkey immunoglobulin isotypes. , 1997, Veterinary immunology and immunopathology.

[6]  D. Smith,et al.  Infection and cross-protection studies of winter dysentery and calf diarrhea bovine coronavirus strains in colostrum-deprived and gnotobiotic calves. , 1996, American journal of veterinary research.

[7]  J. Lunney,et al.  Cellular immune responses of pigs after primary inoculation with porcine respiratory coronavirus or transmissible gastroenteritis virus and challenge with transmissible gastroenteritis virus , 1995, Veterinary Immunology and Immunopathology.

[8]  J. Spencer,et al.  Cell-mediated and humoral immune responses in chickens infected with Salmonella typhimurium. , 1995, Avian diseases.

[9]  J. M. Sharma,et al.  Studies on lymphocyte subpopulations and the effect of age on immune competence in turkeys. , 1993, Developmental and comparative immunology.

[10]  F. Pierson,et al.  Optimum conditions for the turkey lymphocyte transformation test. , 1992, Avian diseases.

[11]  J. M. Sharma,et al.  Blastogenic response of whole blood cells of turkeys to a T-cell mitogen. , 1992, Developmental and comparative immunology.

[12]  S. Dea,et al.  Identification of Coronaviruses by the Use of Indirect Protein A-Gold Immunoelectron Microscopy , 1991, Journal of veterinary diagnostic investigation : official publication of the American Association of Veterinary Laboratory Diagnosticians, Inc.

[13]  J. Beaubien,et al.  Coronaviruses associated with outbreaks of transmissible enteritis of turkeys in Quebec: hemagglutination properties and cell cultivation. , 1986, Avian diseases.

[14]  K. Nagaraja,et al.  Immunofluorescent studies on localization of secretory immunoglobulins in the intestines of turkeys recovered from turkey coronaviral enteritis. , 1980, American journal of veterinary research.

[15]  K. Nagaraja,et al.  Cell-mediated immunity against turkey coronaviral enteritis (bluecomb). , 1980, American journal of veterinary research.

[16]  K. Nagaraja,et al.  Secretory antibodies against turkey coronaviral enteritis. , 1978, American journal of veterinary research.

[17]  B. S. Pomeroy,et al.  Indirect fluorescent antibody test for the diagnosis of coronaviral enteritis of turkeys (bluecomb). , 1976, American journal of veterinary research.

[18]  B. S. Pomeroy,et al.  Fluorescent antibody test for rapid diagnosis of coronaviral enteritis of turkeys (bluecomb). , 1975, American journal of veterinary research.

[19]  L. Reed,et al.  A SIMPLE METHOD OF ESTIMATING FIFTY PER CENT ENDPOINTS , 1938 .