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Cattle vaccination against bovine tuberculosis (bTB) has been proposed as a supplementary method to help control the incidences of this disease. Bacillus Calmette-Guérin (BCG) is currently the only viable candidate vaccine for immunization of cattle against bTB, caused by Mycobacterium bovis (M. bovis). In an attempt to characterize the differences in the immune response following M. bovis infection between BCG-vaccinated and non-vaccinated animals, a combination of gross pathology, histopathology and immunohistochemical (IHC) analyses was used. BCG vaccination was found to significantly reduce the number of gross and microscopic lesions present within the lungs and lymph nodes. Additionally, the microscopically visible bacterial load of stages III and IV granulomas was reduced. IHC using cell surface markers revealed the number of CD68+ (macrophages), CD3+ (T lymphocytes) and WC1+ cells (γδ T cells) to be significantly reduced in lymph node granulomas of BCG-vaccinated animals, when compared to non-vaccinated animals. B lymphocytes (CD79a+) were significantly increased in BCG-vaccinated cattle for granulomas at stages II, III and IV. IHC staining for iNOS showed a higher expression in granulomas from BCG-vaccinated animals compared to non-vaccinated animals for all stages, being statistically significant in stages I and IV. TGFβ expression decreased alongside the granuloma development in non-vaccinated animals, whereas BCG-vaccinated animals showed a slight increase alongside lesion progression. IHC analysis of the cytokines IFN-γ and TNF-α demonstrated significantly increased expression within the lymph node granulomas of BCG-vaccinated cattle. This is suggestive of a protective role for IFN-γ and TNF-α in response to M. bovis infection. Findings shown in this study suggest that the use of BCG vaccine can reduce the number and severity of lesions, induce a different phenotypic response and increase the local expression of key cytokines related to protection.

By using replication-defective vectors derived from human immunodeficiency virus type 1 (HIV-1), simian immunodeficiency virus (SIVmac), and murine leukemia virus (MuLV), all of which were pseudotyped with the vesicular stomatitis virus (VSV) G glycoprotein, the efficiency of postentry, early infection events was examined in target cells of several mammalian species. Titers of HIV-1 vectors were significantly lower than those of SIVmacand MuLV vectors in most cell lines and primary cells from Old World monkeys. By contrast, most New World monkey cells exhibited much lower titers for the SIVmac vector compared with those of the HIV-1 vector. Prosimian cells were resistant to both HIV-1 and SIVmac vectors, although the MuLV vector was able to infect these cells. Cells from other mammalian species were roughly equivalent in susceptibility to the three vectors, with the exception of rabbit cells, which were specifically resistant to the HIV-1 vector. The level of HIV-1 vector expression was very low in transduced cells of rodent, rabbit, cow, and pig origin. Early postentry restriction of primate immunodeficiency virus infection exhibits patterns largely coincident with species borders and applies to diverse cell types within an individual host, suggesting the involvement of species-specific, widely expressed cellular factors.

Tuberculosis (TB) is the most important zoonotic bacterial disease in nonhuman primates (NHP).Tuberculosis (TB) remains one of the most important bacterial diseases of nonhuman primates (NHP) because of its frequency of occurrence, ability to spread rapidly, high mortality rates, and zoonotic potential (14,26,32). The disease in NHP is caused by the same organisms that are responsible for TB in humans (Mycobacterium tuberculosis) and cattle (Mycobacterium bovis) (4,11,33,35). Infection can be readily transmitted from one monkey to another or from monkeys to humans and vice versa (26,31).To control the spread of this devastating illness, captive NHP are screened for TB regularly. The USDA-approved method tests for delayed hypersensitivity in response to an intradermal injection of mammalian old tuberculin (MOT) into the skin of the eyelid (intrapalpebral tuberculin test) (8). MOT is composed of poorly defined mycobacterial antigens that are known to be highly cross-reactive (12, 25). The visual scoring of the test is largely subjective, often allowing confusion between negative and positive results (6, 15). In spite of rigorous testing and import quarantine measures, outbreaks of TB in NHP continue to occur in research laboratories, resulting in the destruction of numerous valuable animals in the United States and elsewhere (14, 32). Many healthy primates are also euthanized unnecessarily because of false-positive skin test reactions that might be due to a nonspecific inflammatory response to MOT or because of sensitization with cross-reactive nonpathogenic species of environmental mycobacteria (10,15,17,19). Thus, alternative diagnostic approaches for antemortem TB testing of NHP are urgently needed.We have recently developed two membrane-based antibody detection methods, MultiAntigen Print ImmunoAssay (MAPIA) and a lateral-flow test, and demonstrated the potential for rapid TB serodiagnosis in various host species (16,23,34). In the present study, we characterized the antibody responses in NHP experimentally infected with M. tuberculosis and developed the PrimaTB STAT-PAK assay, a novel lateral-flow test for antibody detection in TB. This test was evaluated in comparison with the intradermal palpebral tuberculin test and other laboratory diagnostic methods over the course of experimental infection. MATERIALS AND METHODS Animals and infection.A total of 422 NHP were used, including 243 rhesus (Macaca mulatta), 46 cynomolgus (Macaca fascicularis), and 133 African green (Cercopithecus aethiops sabaeus) monkeys from five collaborative centers (Table 1). At four research sites, experimental infection with M. tuberculosis was performed on 50 animals, including 29 rhesus, 16 cynomolgus, and 5 African green monkeys. Animal infection experiments were performed in biosafety level 3 facilities according to the study protocols approved by the Institutional Animal Care and Use Committees. After prestudy quarantine and extensive evaluation for TB, monkeys were inoculated intratracheally with various doses and strains of M. ...