Department of Population Health Sciences

Permanent URI for this community

https://hdl.handle.net/10919/24262

Browse

Browsing Department of Population Health Sciences by Subject "0707 Veterinary Sciences"

Now showing 1 - 3 of 3
  • Thumbnail Image
    Can levamisole upregulate the equine cell-mediated macrophage (M1) dendritic cell (DC1) T-helper 1 (CD4 Th1) T-cytotoxic (CD8) immune response in vitro?
    Witonsky, Sharon G.; Buechner-Maxwell, Virginia A.; Santonastasto, Amy; Pleasant, R. Scott; Werre, Stephen R.; Wagner, Bettina; Ellison, Siobhan; Lindsay, David S. (Wiley, 2019-03-01)
    Background: Equine protozoal myeloencephalitis (EPM) is a common and devastating neurologic disease of horses in the United States. Because some EPM-affected horses have decreased immune responses, immunomodulators such as levamisole have been proposed as supplemental treatments. However, little is known about levamisole's effects or its mechanism of action in horses. Objective: Levamisole in combination with another mitogen will stimulate a macrophage 1 (M1), dendritic cell 1 (DC1), T-helper 1 (CD4 Th1), and T-cytotoxic (CD8) immune response in equine peripheral blood mononuclear cells (PBMCs) in vitro as compared to mitogen alone. Animals: Ten neurologically normal adult horses serologically negative for Sarcocystis neurona. Methods: Prospective study. Optimal conditions for levamisole were determined based on cellular proliferation. Peripheral blood mononuclear cells were then cultured using optimal conditions of mitogen and levamisole to identify the immune phenotype, based on subset-specific activation markers, intracellular cytokine production, and cytokine concentrations in cell supernatants. Subset-specific proliferation was determined using a vital stain. Results: Concanavalin A (conA) with levamisole, but not levamisole alone, resulted in a significant decrease (P <.05) in PBMC proliferation compared to conA alone. Levamisole alone did not elicit a specific immune phenotype different than that induced by conA. Conclusion and Clinical Importance: Levamisole co-cultured with conA significantly attenuated the PBMC proliferative response as compared with conA. If the mechanisms by which levamisole modulates the immune phenotype can be further defined, levamisole may have potential use in the treatment of inflammatory diseases.
  • Thumbnail Image
    Leptospira Seroprevalence Among Ugandan Slaughter Cattle: Comparison of Sero-Status With Renal Leptospira Infection
    Alinaitwe, Lordrick; Kankya, Clovice; Namanya, Dianah; Pithua, Patrick; Dreyfus, Anou (Frontiers, 2020-02-28)
    Despite evidence of both human and animal Leptospira exposures in Uganda, the epidemiology of the disease is still not well-investigated. Contact with animals and their environments have been pointed out as potential source of infection with Leptospira species in humans; and cattle may be an important reservoir in Uganda. In this cross-sectional study, we estimated the prevalence of anti-Leptospira antibodies by the standard microscopic agglutination test (MAT); and associated risk factors among slaughtered cattle. We also compared the performance of the MAT used in this study against a lipL32 based real time PCR (qPCR) assay previously conducted on the kidneys and urine of the same slaughter cattle as tested in this reported study. Of 500 cattle sampled, 27.8% (95% CI 23.9–32.0) tested positive (titer ≥ 100) to at least one Leptospira serovar, with the majority of seropositive cattle reacting to serovars Tarassovi (sg Tarassovi) (11.6%), Sejroe (Sg Sejroe) (7.8%), and Australis (Sg Australis) (5.2%). Older animals had 2.8 times (95% CI 1.0–8.2, p-value 0.055) greater odds of being seropositive than younger ones (<1.5 years). The sensitivity and specificity of the MAT over the qPCR were 65.9% (95% CI 50.1–79.5) and 75.9% (95% CI 71.7–79.7), respectively; with a negative predictive value of 95.8% and positive predictive value of 20.9%. In conclusion, slaughter cattle in this study were significantly exposed to pathogenic Leptospira species of mainly the Tarassovi, Sejroe, and Australis serogroups, with seroprevalence being higher among older cattle. The high specificity and negative predictive value of MAT as used in this study when compared to the qPCR assay may imply a rather strong association between seronegativity and absence of renal Leptospira infection. However, MAT predictability for renal Leptospira infection may be interpreted cautiously since predictive values of diagnostic tests are dependent on prevalence.
  • Thumbnail Image
    Model of Success: World Association for the Advancement of Veterinary Parasitology African Foundation (1997-2019)
    Krecek, Rosina Claudia; Avenant-Oldewage, Annemarie; Fisher, Maggie; Penzhorn, Barend L.; Phiri, Isaac K.; Prichard, Roger; Sumption, Derek; Werre, Stephen R. (AOSIS, 2020-08-31)