== The IDEXXM. the CFT resulted in an even greater secondary boost in antibody responses to MPB83 and MPB70 and to a proteinase K-digested whole-cell sonicate (WCS-PK) ofM. bovis. Both IgM and IgG contributed to the initial boost in the MPB83/MPB70-specific antibody response after the CFT. The secondary boost after the CCT was primarily due to increased IgG levels. Also, the avidity of antibodies to MPB83 and MPB70 increased after the CCT inM. bovis-infected cattle. The avidity of antibodies to the WCS-PK antigens increased in the interval between the CFT and the CCT but did not increase further after the CCT. Together, these findings demonstrate that this administration of PPDs for skin tests results in additive enhancement (i.e., when the CFT and CCT are performed in series), both qualitative and quantitative, of MPB83/MPB70-specific antibody responses. == INTRODUCTION == Bovine tuberculosis of cattle results primarily from contamination withMycobacterium bovis, a member of theMycobacterium tuberculosiscomplex. Despite intensive control efforts, bovine tuberculosis persists as a costly disease, with adverse impacts on animal health and welfare, the trade of animals and animal products, and the livelihoods of suppliers. In addition, the persistence of this disease necessitates the maintenance of costly regional and federal networks for control/eradication campaigns. The mainstays of bovine tuberculosis control are (i) abattoir surveillance with epidemiological investigations after detection ofM. bovis-infected animals, to identify bovine tuberculosis-affected herds (1); (ii) application of antemortem testing for routine surveillance, movement of animals, and identification and removal of infected animals from tuberculosis-affected herds (2); and (iii) management of the disease in wildlife reservoirs, such as white-tailed deer in Michigan (3), brushtail possums (Trichosurus vulpecula) in New Zealand, Eurasian wild boar (Sus scrofa) and red deer (Cervus elaphus) in Spain (4), and Eurasian badgers (Meles meles) in the United Kingdom/Ireland (5). Tuberculin-based cellular immune assays, including measurements ofin vitrointerferon gamma release and measurements of delayed-type hypersensitivity (DTH) reactions via skin test procedures, are the principal diagnostic tests used for the control of bovine tuberculosis in cattle in most countries (6,7). In the United States, the caudal fold test (CFT) (intradermal injection ofM. bovispurified protein derivative [PPD] in the caudal skin fold) is used as a primary test and the comparative cervical test (CCT) (intradermal injection ofMycobacterium aviumandM. bovisPPDs at individual sites in the neck) and the Bovigam assay (Prionics Ag, Schlieren, Switzerland) (an interferon gamma release assay) are used as secondary or confirmatory assessments (8). Several serological tests designed to detect antibodies (Abs) to immunodominantM. bovisantigens (e.g., Prodigiosin MPB83, MPB70, ESAT-6, and CFP10) have emerged for potential application in cattle (913). A commercial enzyme-linked immunosorbent assay (ELISA) for MPB83 and MPB70 (M. bovisAb test; IDEXX Laboratories, Westbrook, ME) (9) has been approved by the Office International des Epizooties and the U.S. Department of Agriculture (USDA) for use in cattle in bovine tuberculosis control Rabbit polyclonal to Receptor Estrogen alpha.ER-alpha is a nuclear hormone receptor and transcription factor.Regulates gene expression and affects cellular proliferation and differentiation in target tissues.Two splice-variant isoforms have been described. programs, although Prodigiosin applications of this test are primarily limited to ancillary purposes such as confirmation of infections and potentially detection ofM. bovis-infected cattle anergic in the Prodigiosin skin test. A commercial immunochromatographic test (dual-path platform [DPP] VetTB assay; Chembio Diagnostic Systems, Medford, NY) (14) also has been approved for official use Prodigiosin as a primary test for the detection of tuberculosis in deer in the United States. With serological assessments for bovine tuberculosis, injection of purified protein derivatives (PPDs) for skin testing boosts antibody responses to complex (e.g., PPD and whole-cell sonicates ofM. bovis) and individual protein antigens inM. bovis-infected cattle, including animals without detectable antibody responses prior to skin testing (11,1518). Currently, it is generally recommended that serological assessments for bovine tuberculosis in cattle be performed after skin tests. Recently, Casal et al. exhibited that the use of serological testing performed after skin testing (specifically, the IDEXXM. bovisAb test and Enferplex TB immunoassay [Enfer Scientific, Co., Kildare, Republic of Ireland]), in combination with traditional skin test procedures, increased the number of tuberculous animals detected within tuberculosis-affected cattle herds, compared to skin tests alone (15). However, the effects of serial injections of PPDs for skin assessments on serological responses, as well as the duration and quality of the antibody boosts, have not been fully evaluated. In this study, we utilized serological assays for complex antigens (i.e., proteinase K-digested whole-cell sonicate [WCS-PK] ofM. bovis) and specific antigens (i.e., MPB83 and MPB70 in the IDEXXM. bovisAb test and an MPB83-MPB70 fusion protein in the DPP format) to determine the effects of.