Dysregulation of Chemokine/Chemokine Receptor Axes and NK Cell Tissue Localization during Diseases.

Chemokines are small chemotactic molecules that play key roles in physiological and pathological conditions. Upon signaling via their specific receptors, chemokines regulate tissue mobilization and trafficking of a wide array of immune cells, including natural killer (NK) cells. Current research is focused on analyzing changes in chemokine/chemokine receptor expression during various diseases to interfere with pathological trafficking of cells or to recruit selected cell types to specific tissues. NK cells are a heterogeneous lymphocyte population comprising several subsets endowed with distinct functional properties and mainly representing distinct stages of a linear development process. Because of their different functional potential, the type of subset that accumulates in a tissue drives the final outcome of NK cell-regulated immune response, leading to either protection or pathology. Correspondingly, chemokine receptors, including CXCR4, CXCR3, and CX3CR1, are differentially expressed by NK cell subsets, and their expression levels can be modulated during NK cell activation. At first, this review will summarize the current knowledge on the contribution of chemokines to the localization and generation of NK cell subsets in homeostasis. How an inappropriate chemotactic response can lead to pathology and how chemokine targeting can therapeutically affect tissue recruitment/localization of distinct NK cell subsets will also be discussed

The Transcription Factor Tcf1 Contributes to Normal NK Cell Development and Function by Limiting the Expression of Granzymes.

The transcription factor Tcf1 is essential for the development of natural killer (NK) cells. However, its precise role has not been clarified. Our combined analysis of Tcf1-deficient and transgenic mice indicated that Tcf1 guides NK cells through three stages of development. Tcf1 expression directed bone marrow progenitors toward the NK cell lineage and ensured the survival of NK-committed cells, and its downregulation was needed for terminal maturation. Impaired survival of NK-committed cells was due to excessive expression of granzyme B (GzmB) and other granzyme family members, which induced NK cell self-destruction during maturation and following activation with cytokines or target cells. Mechanistically, Tcf1 binding reduced the activity of a Gzmb-associated regulatory element, and this accounted for the reduced Gzmb expression in Tcf1-expressing NK cells. These data identify an unexpected requirement to limit the expression of cytotoxic effector molecules for the normal expansion and function of NK cells

Calorie Restriction Attenuates Terminal Differentiation of Immune Cells

Immune senescence is a natural consequence of aging and may contribute to frailty and loss of homeostasis in later life. Calorie restriction increases healthy life-span in C57BL/6J (but not DBA/2J) mice, but whether this is related to preservation of immune function, and how it interacts with aging, is unclear. We compared phenotypic and functional characteristics of natural killer (NK) cells and T cells, across the lifespan, of calorie-restricted (CR) and control C57BL/6 and DBA/2 mice. Calorie restriction preserves a naïve T cell phenotype and an immature NK cell phenotype as mice age. The splenic T cell populations of CR mice had higher proportions of CD11a-CD44lo cells, lower expression of TRAIL, KLRG1, and CXCR3, and higher expression of CD127, compared to control mice. Similarly, splenic NK cells from CR mice had higher proportions of less differentiated CD11b-CD27+ cells and correspondingly lower proportions of highly differentiated CD11b+CD27-NK cells. Within each of these subsets, cells from CR mice had higher expression of CD127, CD25, TRAIL, NKG2A/C/E, and CXCR3 and lower expression of KLRG1 and Ly49 receptors compared to controls. The effects of calorie restriction on lymphoid cell populations in lung, liver, and lymph nodes were identical to those seen in the spleen, indicating that this is a system-wide effect. The impact of calorie restriction on NK cell and T cell maturation is much more profound than the effect of aging and, indeed, calorie restriction attenuates these age-associated changes. Importantly, the effects of calorie restriction on lymphocyte maturation were more marked in C57BL/6 than in DBA/2J mice indicating that delayed lymphocyte maturation correlates with extended lifespan. These findings have implications for understanding the interaction between nutritional status, immunity, and healthy lifespan in aging populations

Efecto del nivel de suplementación con harina de algodón sobre el consumo y el aumento de peso en bovinos en recría alimentados con silaje de sorgo

El objetivo de este trabajo fue determinar el efecto la suplementación proteica con harina de algodón (HA; 351 g kg-1 PB) a niveles de 0 (P0; Testigo), 3,0 (P1), 6,0 (P2) y 9,0 (P3) g kg-1 de peso vivo (PV), sobre el consumo de materia seca (CMS), consumo de silaje (CS), aumento de peso (ADPV), eficiencia de conversión de los alimentos (IC) y nitrógeno ureico en sangre (NUS) en bovinos jóvenes alimentados con silaje de sorgo (SS). Se emplearon un total de 24 animales, 12 machos castrados y 12 hembras de peso promedio 187 ± 12 kg, distribuidos en 8 corrales a razón de tres por corral en un diseño completamente aleatorizado. El SS de planta entera fue confeccionado, a partir de un híbrido doble propósito (“VDH 422”), en el estadio de grano pastoso. La duración del experimento fue de 98 días, con 14 días de acostumbramiento y 84 de medición. Las variables fueron sometidas a análisis de la varianza, y los tres grados de libertad pertenecientes a los tratamientos se particionaron en contrastes lineal, cuadrático y cúbico. El CMS, ADPV, IC y NUS se incrementaron (p>0,05) en forma cuadrática con el aumento en el nivel de suplementación, con excepción del NUS que presentó efecto cúbico (C<0,05). El consumo de silo (CS) expresado en kg MS an-1 d-1 difirió (p<0,05) con el aumento del nivel de suplementación, pero no se detectan diferencias (p=0,12) como g kg-1 PV, aunque en ambos casos se verificó un efecto cuadrático (Q<0,05). El tratamiento testigo (P0) presentó un ADPV de 0,07 kg an-1 d-1, con un CS de 18,2 g kg-1 PV que se incrementó 31,3% al incluir 3 g kg-1 PV de HA. La evidencia permite concluir que no es recomendable la utilización del silaje de sorgo como único alimento. La suplementación con harina de algodón tuvo un efecto positivo sobre CMS, CS, ADPV e IC, siendo recomendable hasta el nivel de 6 g kg-1 del peso vivo, ya que un nivel superior no cambia estas variables.The aim of this work to was study the effect of protein supplementation with Cottonseed meal (CSM; 351 g kg-1 PB) at levels of 0 (P0; Control), 3,0 (P1), 6,0 (P2) y 9,0 (P3) g kg-1 of live weight (LW), on total dry matter intake (DMI), silage dry matter intake (SI) average daily gain (AVG), feed conversion efficiency (FC) and blood urea nitrogen (BUN) in young beef cattle fed with sorghum silages. Twelve steers and twelve heifers averaging 8 months of age and 187 ± 12 kg, were distributed in 8 pens in a completely randomized design. Whole plant sorghum silage was made from double purpose hybrid, at late-dough stage of maturity. The experiment lasted 98 days, with 14 days for adaptation and 84 days for measurement. The variables were subjected to analysis of variance, and the three degrees of freedom from the traits were partitioned in lineal, quadratic and cubic effect contrast. DMI, AVG, FC and BUN increased (p<0,05) in a quadratic manner with supplementation level, except BUN that showed cubic effect (p<0,05). SI in kg DM an-1 d-1 was different (p<0,05) with the increase of supplementation level, but there was not different (p=0,12) expressed as g kg-1 BW, although in both cases a quadratic effect was observed (p<0,05). AVG of Control (P0) was 0,07 kg an-1 d-1, with a 18,2 g kg-1 LW of SI, that was increased 31,3% when was included 3 g kg-1 LW of CSM. The results of the assessments show that is not recommended feed young animals with sorghum silages as only feed. Supplementation with CSM had a positive effect on DMI, SI, ADG and FC, being recommended a 6 g kg-1 LW level, because a superior level showed no improvement.EEA Sáenz PeñaFil: Chiossone, José Luciano. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Sáenz Peña; ArgentinaFil: Chiossone, José Luciano. Universidad Nacional del Chaco Austral; ArgentinaFil: Balbuena, Osvaldo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Colonia Benítez; ArgentinaFil: Balbuena, Osvaldo. Universidad Nacional del Nordeste; Argentin

Dendritic Cell Editing by Activated Natural Killer Cells Results in a More Protective Cancer-Specific Immune Response

Over the last decade, several studies have extensively reported that activated natural killer (NK) cells can kill autologous immature dendritic cells (DCs) in vitro, whereas they spare fully activated DCs. This led to the proposal that activated NK cells might select a more immunogenic subset of DCs during a protective immune response. However, there is no demonstration that autologous DC killing by NK cells is an event occurring in vivo and, consequently, the functional relevance of this killing remains elusive. Here we report that a significant decrease of CD11c+ DCs was observed in draining lymph nodes of mice inoculated with MHC-devoid cells as NK cell targets able to induce NK cell activation. This in vivo DC editing by NK cells was perforin-dependent and it was functionally relevant, since residual lymph node DCs displayed an improved capability to induce T cell proliferation. In addition, in a model of anti-cancer vaccination, the administration of MHC-devoid cells together with tumor cells increased the number of tumor-specific CTLs and resulted in a significant increase in survival of mice upon challenge with a lethal dose of tumor cells. Depletion of NK cells or the use of perforin knockout mice strongly decreased the tumor-specific CTL expansion and its protective role against tumor cell challenge. As a whole, our data support the hypothesis that NK cell-mediated DC killing takes place in vivo and is able to promote expansion of cancer-specific CTLs. Our results also indicate that cancer vaccines could be improved by strategies aimed at activating NK cells

Opciones de uso de soja dañada en alimentación de bovinos en emergencia

Debido a las condiciones meteorológicas registradas, se retrasó la cosecha de muchos lotes de soja en el sudoeste chaqueño resultando en una pérdida de calidad de los granos con el consecuente castigo comercial. Esta soja dañada de menor valor comercial puede funcionar como una alternativa para ser utilizada en alimentación de bovinos, pero deben tener en cuenta dos aspectos: 1- Modificación de la calidad nutricional 2- Presencia de sustancias toxicas.EEA Colonia BenitezFil: Balbuena, Osvaldo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Colonia Benítez; ArgentinaFil: Chiossone, José Luciano. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Sáenz Peña; ArgentinaFil: Pamies, Marcelo Eduardo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Colonia Benítez; Argentin

Experiencia de recuperación de un área degradada en el oeste formoseño, en el marco del trabajo con pequeños productores ganaderos

En esta experiencia de recuperación de áreas degradadas participaron técnicos de la Estación Experimental del INTA El Colorado y la Agencia de Extensión Rural de Ing. Juárez. Los trabajos se realizaron en el año 2008 en el Paraje El Rosillo ubicado en el Departamento Matacos al Oeste de la Provincia de FormosaEEA Ingeniero JuárezFil: Sanz, Patricio Hugo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Ingeniero Juárez; ArgentinaFil: Chiossone, Guillermo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Ingeniero Juárez; ArgentinaFil: Cavallero, María Inés. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Ingeniero Juárez; Argentin

Destete: ¡La práctica poderosa!

El destete es una práctica, que por sí sola tiene un gran impacto en la eficiencia del rodeo de cría. Esto se debe a que, sacarle el ternero a la vaca implica para ella cambiar el destino final de la energía que está consumiendo. Ya no invertirá en producir leche y esa energía pasará a convertirse en ganancia de peso.EEA ConcordiaFil: Chiossone, José Luciano. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Concordia. Agencia de Extensión Rural Colón; ArgentinaFil: Schreyer, Hector Enrique. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Concordia. Agencia de Extensión Rural San Salvador; ArgentinaFil: Roman, Lilian Mabel. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Concordia; Argentin

Manejo silvopastoril en plantaciones de algarrobo en la provincia del Chaco

El algarrobo en planteos silvopastoriles. El manejo silvopastoril o silvoganadero es un modelo productivo donde se integran en una unidad de manejo simultáneamente la producción maderera/chauchas con el forraje y el pastoreo de animales.Fil: Pernochi, Lorena Soledad. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Sáenz Peña; ArgentinaFil: Atanasio, Marcos Antonio. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Sáenz Peña; ArgentinaFil: Chiossone, José Luciano. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Sáenz Peña; Argentin