The Journal of immunology : official journal of the American Association of Immunologists
-
Hypertonic resuscitation fluids are known to be effective in restoring circulating volume in the hypovolemic trauma patient. Previous studies have suggested that hypertonicity might exert effects on immune cells leading to an altered host response. The present studies evaluated the effect of hypertonic resuscitation on the development of lung injury in a hemorrhagic shock model in which antecedent shock primes for increased lung neutrophil sequestration in response to intratracheal LPS. ⋯ Impaired up-regulation of lung ICAM-1 may have also participated, although ex vivo studies suggest that alterations in neutrophils were sufficient to account for the effect. Lung cytokine-induced neutrophil chemoattractant did not differ between animals resuscitated with hypertonic saline vs Ringer's lactate. Considered together, these studies demonstrate a possible novel approach to inhibiting organ injury in disease processes characterized by neutrophil-mediated damage.
-
To study the relation between the form of an Ag and the response to it, we compared presentation in vitro with hen egg lysozyme (HEL)-specific T cells from TCR transgenic mice of free HEL and liposome-encapsulated HEL by different APC. HEL-specific splenic B cells or bone marrow-derived dendritic cells were incubated with free HEL or HEL-containing liposomes targeted by Ab to either surface Ig, the Fc receptor, or MHC class I and II molecules. ⋯ These results indicate that Ag-specific B cells and dendritic cells can be equally efficient in stimulating IL-2 production by Ag-specific T cells from unimmunized TCR transgenic mice when the Ag is multivalent and taken up by appropriate receptors. In contrast to B cells, which require engagement of surface Ig for optimal presentation, dendritic cells may present Ag by means of several different cell surface molecules.