Aspectos de la respuesta inmune innata en las infecciones intramamarias causadas por Staphylococcus aureus en bovinos

ResumenStaphylococcus aureus es el principal agente causante de mastitis bovina en Argentina y en el mundo. Esta bacteria ocasiona infecciones crónicas que generan importantes pérdidas a los productores y la industria lechera. El objetivo de este artículo es caracterizar los mecanismos que intervienen en la infección causada por S. aureus en la glándula mamaria bovina, evaluando dos aspectos diferentes del proceso infeccioso: por un lado, lo vinculado con la respuesta inmune innata por parte del hospedador, y por otro, la capacidad de la bacteria para evadir el sistema inmune e interactuar con diferentes tipos celulares. La exploración de la interacción de S. aureus con el sistema inmune de la glándula mamaria bovina permitirá identificar blancos para delinear nuevas alternativas preventivas o curativas, que contribuyan a evitar o eliminar las infecciones causadas por este organismo.AbstractStaphylococcus aureus is the pathogen most frequently isolated from bovine mastitis worldwide, causing chronic intramammary infections that limit profitable dairying. The objective of this article is to characterize the mechanisms involved in S. aureus mammary gland infections considering two different aspects of the infectious process; on the one hand, the aspects involved in the host innate immune response and on the other hand, the capacity of this organism to evade the immune system and interact with different cell types. The exploration of S. aureus interactions with the immune response of bovine mammary gland will help identify targets to outline new preventive or curative alternatives for intramammary infections caused by this organism

Sympathetic nerve activity in normal and cystic follicles from isolated bovine ovary: local effect of beta-adrenergic stimulation on steroid secretion

Cystic ovarian disease (COD) is an important cause of abnormal estrous behavior and infertility in dairy cows. COD is mainly observed in high-yielding dairy cows during the first months post-partum, a period of high stress. We have previously reported that, in lower mammals, stress induces a cystic condition similar to the polycystic ovary syndrome in humans and that stress is a definitive component in the human pathology. To know if COD in cows is also associated with high sympathetic activity, we studied isolated small antral (5mm), preovulatory (10mm) and cystic follicles (25mm). Cystic follicles which present an area 600 fold greater compared with preovulatory follicles has only 10 times less concentration of NE as compared with small antral and preovulatory follicles but they had 10 times more NE in follicular fluid, suggesting a high efflux of neurotransmitter from the cyst wall. This suggestion was reinforced by the high basal release of recently taken-up 3H-NE found in cystic follicles. While lower levels of beta-adrenergic receptor were found in cystic follicles, there was a heightened response to the beta-adrenergic agonist isoproterenol and to hCG, as measured by testosterone secretion. There was however an unexpected capacity of the ovary in vitro to produce cortisol and to secrete it in response to hCG but not to isoproterenol. These data suggest that, during COD, the bovine ovary is under high sympathetic nerve activity that in addition to an increased response to hCG in cortisol secretion could participate in COD development

Proinflammatory cytokines and CD14 expression in mammary tissue of cows following intramammary inoculation of Panax ginseng at drying off

The lack of efficacy of conventional strategies for the maintenance of healthy udders in domestic cattle has prompted studies on the use of immunomodulators or biological response modifiers (BRM) for this purpose. These compounds are agents that modify the host's response to pathogens leading to beneficial effects on disease outcome. The objective of this study was to evaluate the effects of a single intramammary infusion of Panax ginseng (GS) extract on the amount of pro-inflammatory cytokines and the number of monocytes/macrophages present in bovine mammary tissues at drying off. Eight mammary quarters from six nonpregnant cows in late lactation were infused with 10 mL of GS (3 mg/mL), six quarters were treated with 10 mL of placebo (vehicle alone) and six quarters were maintained as uninoculated controls. The analyses of tumor necrosis factor-alpha (TNF-α) by immunohistochemistry revealed that the production of this proinflammatory cytokine significantly increased (P < 0.05) in the inoculated mammary glands of cows following BRM inoculation, whereas the interleukin-1 alpha (IL-1α) and IL-6 staining area was not affected by BRM treatment. The number of monocytes/macrophages detected with CD14 antibody was significantly higher (P < 0.05) in BRM-treated quarters than in placebo and uninoculated control quarters. These results indicated an immunomodulator potential of the BRM used. The beneficial effect of the extract could be used as alternative therapy in the control of mastitis at drying off, either alone or in conjunction with dry cow antibiotic therapy.Fil: Baravalle, Celina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Ciencias Veterinarias del Litoral; Argentina; Argentina. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias ; ArgentinaFil: Dallard, Bibiana Elisabet. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Ciencias Veterinarias del Litoral; Argentina; Argentina. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias ; ArgentinaFil: Cadoche, M. C.. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias ; ArgentinaFil: Pereyra, Elizabet Amanda Lorena. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias ; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Ciencias Veterinarias del Litoral; Argentina; ArgentinaFil: Neder, V. E.. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Ortega, H. H.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Ciencias Veterinarias del Litoral; Argentina; Argentina. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias ; ArgentinaFil: Calvinho, L. F.. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias ; Argentina. Instituto Nacional de Tecnología Agropecuaria; Argentin

Cellular proliferation rate, and IGFBP-2 and -3 and estradiol receptor alpha expression in the mammary gland of dairy heifers naturally infected with gastrointestinal nematodes during development

Mammary ductal morphogenesis during prepuberty occurs mainly in response to insulin-like growth factor-1 (IGF-1) and estradiol stimulation. Dairy heifers infected with gastrointestinal nematodes have reduced IGF-1 levels, accompanied by reduced growth rate,delayed puberty onset, and lower parenchyma-stroma relationship in their mammary glands. Immunohistochemical studies were undertaken to determine variations in cell division rate, IGF-1 system components, and estradiol receptors (ESR) during peripubertal development in the mammary glands of antiparasitictreated and untreated Holstein heifers naturally infected with gastrointestinal nematodes. Mammary biopsies were taken at 20, 30, 40, and 70 wk of age. Proliferating cell nuclear antigen immunolabeling, evident in nuclei, tended to be higher in the parenchyma of the glands from treated heifers than in those from untreated. IGF binding proteins (IGFBP) type 2 and type 3 immunolabeling was cytoplasmic and was evident in stroma and parenchyma. The IGFBP2-labeled area was lower in treated than in untreated heifers. In the treated group, a maximal expression of this protein was seen at 40 wk of age, whereas in the untreated group the labeling remained constant. No differences were observed for IGFBP3 between treatment groups or during development. Immunolabeling for α ESR (ESR1) was evident in parenchymal nuclei and was higher in treated than in untreated heifers. In the treated group, ESR1 peaked at 30 wk of age and then decreased. These results demonstrate that the parasite burden in young heifers negatively influence mammary gland development, affecting cell division rate and parameters related to estradiol and IGF-1 signaling in the gland.Fil: Perri, Adrián Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental (i); Argentina. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias; ArgentinaFil: Dallard, Bibiana Elisabet. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias; ArgentinaFil: Baravalle, Celina. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias; ArgentinaFil: Licoff, N.. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental (i); ArgentinaFil: Formia, N.. Universidad Nacional de La Plata; ArgentinaFil: Ortega, Hugo Hector. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias; ArgentinaFil: Becu, Damasia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental (i); ArgentinaFil: Mejia, M. E.. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental (i); ArgentinaFil: Lacau, Isabel Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental (i); Argentin