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cells that destroy virus-infected cells. 1,7 CD4+ Th2 cells produce IL-4, the cytokine that induces an antibody response. 1,7 γδ T cells have a number of functions within the immune system, and their exact role in humoral immunity and CMI remains

Full access
in American Journal of Veterinary Research

Summary

Vaccina virus (VV) infection induces specific antibodies and cytotoxic T cells in various animal species. Therefore, helper T cells also should be induced that stimulate the humoral and cellular immune responses. We determined such helper T-cell activity in 2 species after VV infection. Rabbits and rhesus macaques were infected with the Copenhagen strain of VV or with recombinant VV expressing retroviral proteins. Animals of both species developed antibodies and specific proliferative T-cell response. This reactivity could be enhanced by booster infection with VV. The proliferating macaque cells were CD4+ and major histocompatability complex class Il-restricted. These data confirm the broad immunogenicity of VV. Expression of additional polypeptides expressed from a recombinant VV does not lead to altered immune response to VV antigens. However, strength of the helper T-cell response, as well as clinical reactions, differed between macaques and rabbits. Infection with recombinant VV as delivery vectors offers the opportunity for combined vaccination against recombinant proteins and does not diminish cellular and humoral immune responses to VV itself.

Free access
in American Journal of Veterinary Research

immune responses against intracellular bacteria. 14 – 19 mRNA vaccines have gained attention for their success against COVID-19 20 because they can achieve superior cell-mediated and humoral immune responses to those from traditional vaccines. 21 , 22

Open access
in American Journal of Veterinary Research

injection-site reactions and humoral immune responses in cattle vaccinated with a clostridial vaccine administered SC by use of a needle and syringe or via TD needle-free injection. Materials and Methods Animals —Sixteen 11- to 12-month-old Herefords

Full access
in American Journal of Veterinary Research

Summary

The IgG and IgM classes of antibodies to a watersoluble antigen preparation derived from Microsporum canis were determined by elisa in the sera of 79 cats with dermatophytosis confirmed by results of fungal culture, and of 46 specific-pathogen-free-derived, barrier-maintained cats with no previous exposure to dermatophytes. Of the 79 cats with dermatophytosis, the species isolated were: M canis from 72, M gypseum from 6, and Trichophyton mentagrophytes from 1.

Concentrations of soluble M canis antigen-specific IgG and IgM were significantly (P < 0.05) higher in the cats with dermatophytosis than in the control cats. The IgG concentration was ≥ 2.0 elisa units/ml in 71% of the cats with dermatophytosis and in 9% of the control cats, whereas IgM concentration was ≥ 4.0 elisa units/ml in 38% of the cats with dermatophytosis and in 11% of control cats. There was no significant difference in either IgG or IgM values between the cats with M canis infection and those with other non-M canis dermatophyte infections.

Free access
in American Journal of Veterinary Research

Summary

Sera from cats with naturally acquired and experimentally induced feline immunodeficiency virus (fiv) infections were tested by immunoblot analysis, radioimmunoprecipitation assay (ripa), and a complex trapping/ blocking elisa. In sequentially obtained samples from experimentally inoculated cats, antibodies against the envelope protein gp120 and the core protein pl5 were the first to appear, as indicated by results of ripa, using lysates of fiv-infected lymphocytes. Antibodies could be detected as early as 2 weeks after infection, followed by a response against p24, p43, and p50. By immunoblot analysis, p24 and p15 were the first proteins detectable between postinoculation weeks 3 and 5; an anti-envelope response was never found by use of this assay, but was found by ripa. Using the latter test, most sera of naturally infected cats were found to recognize the major core protein p24 in addition to 1 or more minor core proteins. All 40 sera tested precipitated the envelope protein; 3 reacted exclusively with it. A complex trapping/blocking elisa was developed to quantitate the anti-p24 response. Sera from healthy Fiv-infected cats were shown to have higher anti-p24 titer than did those from diseased cats.

Free access
in American Journal of Veterinary Research

Summary

Eighty gestating beef cattle were used to determine the effect of trace mineral salt mixtures containing copper (Cu) and iron (Fe) on selected immune functions and factors affecting copper bioavailability. Pastured cattle were randomly assigned to receive one of the following combinations of Cu and Fe in the free-choice trace mineral salt: (1) 0 mg of Cu/0 mg of Fe/kg of trace mineral salt, (2) 1,600 mg of Cu (CuSO4)/3,000 mg of Fe/kg of trace mineral salt, (3) 1,600 mg of Cu (CuSO4)/0 mg of Fe/kg of trace mineral salt, and (4) 1,600 mg of Cu (CuCO3)/3,000 mg of Fe/kg of trace mineral salt. Total Cu/Fe consumption (from trace mineral salt) was 2/678, 193/1,050, 162/553, and 202/1,140 mg/head/d, respectively, for the 4 groups. After a 1-month period of acclimation and also on day 28 of the 36-day study, copper concentrations in serum were significantly (P < 0.05) lower in group 1 than in groups 3 and 4. Serum copper concentrations did not increase with time for any group, whereas hepatic copper concentrations increased significantly (P < 0.05) with time for all groups except group 1. Hepatic iron concentrations were similar among groups at the time of the initial and final hepatic biopsies on days 0 and 28, respectively. Hepatic iron concentrations increased significantly (P < 0.05) with time in groups 3 and 4.

Humoral response to chicken γ-globulin was high but did not differ among groups on any of the days analyzed. Neutrophil function tests, consisting of hydrogen peroxide production, phagocytosis of latex particles, calcium uptake, and superoxide production, were different only for phagocytosis among groups; the percentage of neutrophils phagocytizing latex beads was significantly (P < 0.05) lower for group 2 than the other groups. A similar reduction in phagocytosis was prevented by the omission of additional Fe from the trace mineral salt (groups 1 and 3) or use of CuCO3 (group 4).

Free access
in Journal of the American Veterinary Medical Association

SUMMARY

Pseudorabies virus (prv) immediate-early (ie) protein is a nonglycosylated polypeptide localized in the nuclei of infected cells. The ie protein is a regulatory protein that is only synthesized during viral replication and is presented to the immune system of prv-infected swine. Antibodies to the ie protein were demonstrated in swine with induced or naturally acquired infection. However, antiserum raised against purified ie protein could not neutralize prv in vitro.

Free access
in American Journal of Veterinary Research

Abstract

Objective

To investigate ovarian responses and kinetics of gonadotropin-binding immunoglobulin production in domestic cats repeatedly treated with equine chorionic gonadotropin (eCG) and human chorionic gonadotropin (hCG) at short or long treatment intervals.

Design

Queens were treated 3 or 4 times with a standard eCG/hCG regimen at short (49 to 57 days) or long (130 to 135 days) intervals and subjected to laparoscopy after each treatment to evaluate ovarian follicular development. Serial serum samples were assessed by ELISA for the presence of eCG-binding immunoglobulins.

Animals

11 clinically normal sexually mature female cats.

Results

Queens repeatedly stimulated with eCG/hCG at long intervals typically had no decrease (P > 0.05) in ovarian follicle production or in maturity of recovered oocytes, whereas queens treated at short intervals had reduced (P < 0.05) follicular development and compromised oocyte maturity by the third stimulation. For both interval groups, ELISA data indicated individual variability in seroconversion after eCG/hCG challenge exposure. In general, queens treated at short intervals had higher peak anti-eCG immunoglobulin titer than did queens treated at long intervals; high titer at the time of eCG/hCG injection, or rapid increases in titer immediately after injection were predictive (P < 0.05) of poor ovarian responses.

Conclusions

Results suggest that individual variability in immune responses and intervals between repeated gonadotropin treatments determine whether queens develop immunologically mediated ovarian refractoriness to exogenous gonadotropins. Intervals of at least 4 months between successive eCG/hCG treatments are recommended for assisted reproductive procedures in domestic and nondomestic cats.(Am J Vet Res 1996;57:302-307)

Free access
in American Journal of Veterinary Research

Abstract

Objective—To evaluate canarypox-vectored equine influenza virus (EIV) vaccines expressing hemagglutinins of A/equine/Kentucky/94 (vCP1529) and A2/equine/Ohio /03 (vCP2242) for induction of antibody responses against canine influenza virus (CIV) in dogs.

Animals—35 dogs.

Procedures—Dogs were randomly allocated into 4 groups; group 1 (n = 8) and group 2 (9) were inoculated SC on days 0 and 28 with 1.0 mL (approx 105.7 TCID50) of vCP1529 and vCP2242, respectively. Dogs in group 3 (n = 9) were inoculated twice with 0.25 mL (approx 105.7 TCID50) of vCP2242 via the transdermal route. The 9 dogs of group 4 were control animals. All dogs were examined for adverse reactions. Sera, collected on days −1, 7, 13, 21, 28, 35, and 42, were tested by hemagglutination inhibition (HI) and virus neutralization (VN) assays for antibodies against CIV antigens A/Canine/FL/43/04-PR and A/Canine/NY/115809/05, respectively.

Results—Inoculations were tolerated well. The HI and VN antibodies were detected by 7 days after primary inoculation. Most dogs of groups 1 and 2 and all dogs of group 3 had detectable antibodies by 14 days after initial inoculation. The second inoculation induced an anamnestic response, yielding geometric mean HI titers of 139, 276, and 1,505 and VN titers of 335, 937, and 3,288 by day 42 (14 days after booster inoculation) in groups 1, 2, and 3, respectively.

Conclusions and Clinical Relevance—Canarypox-vectored EIV vaccines induce biologically important antibodies and may substantially impact CIV transmission within a community and be of great value in protecting dogs against CIV-induced disease.

Full access
in American Journal of Veterinary Research