Generation of mice deficient for macrophage galactose- and N-acetylgalactosamine-specific lectin: limited role in lymphoid and erythroid homeostasis and evidence for multiple lectins. | LitMetric
Macrophage receptors function in pattern recognition for the induction of innate immunity, in cellular communication to mediate the regulation of adaptive immune responses, and in the clearance of some glycosylated cells or glycoproteins from the circulation. They also function in homeostasis by initiating the engulfment of apoptotic cells. Evidence has suggested that macrophage receptors function to recognize cells that are destined for programmed cell death but not yet overtly apoptotic. We have examined the function of a macrophage receptor specific for unsialylated glycoproteins, known as the mouse macrophage galactose- and N-acetylgalactosamine-specific lectin (mMGL) (Ii et al., J. Biol. Chem. 265:11295-11298, 1990; Sato et al., J. Biochem. [Tokyo] 111:331-336, 1992; Yamamoto et al., Biochemistry 33:8159-8166, 1994). With targeted disruption, we tested whether mMGL is necessary for macrophage function, controlled thymic development, the loss of activated CD8 T cells, and the turnover of red blood cells. Evidence indicates that mMGL may play a nonessential role in several of these macrophage functions. Experiments are presented that indicate the existence of another galactose- and N-acetylgalactosamine-recognizing lectin distinct from mMGL. This may explain the absence of a strong phenotype in mMGL-deficient mice.
The interception of blood-borne bacteria in the liver defines the outcomes of invasive bacterial infections, but the mechanisms of this antibacterial immunity are not fully understood. This study shows that natural antibodies (nAbs) to capsules enable liver macrophage Kupffer cells (KCs) to rapidly capture and kill blood-borne encapsulated bacteria in mice. Affinity pulldown with serotype-10A capsular polysaccharides (CPS10A) of Streptococcus pneumoniae (Spn10A) led to the identification of CPS10A-binding nAbs in serum.
The foaming and polarization of macrophages are pivotal in the formation and development of atherosclerosis. This study delved into the structure and membrane pattern recognition receptors (PRRs) of the neutral polysaccharide fraction (PPRLMF-1), investigating effects of PPRLMF-1 and acid polysaccharide fraction (PPRLMF-2) on the foaming and polarization of RAW264.7 macrophage cells, and exploring their underlying mechanisms.
Jujube ( Mill.) has been consumed globally as a fruit and a nutraceutical food for millennia. This study presents the isolation and purification of a novel water-soluble polysaccharide fraction, ZJMP-2, from Mill.
Bronchial asthma remains a serious medical problem, as approximately 10% of patients fail to achieve adequate symptom control with available treatment options. Macrophages play a pivotal role in the pathophysiology of asthma, as well as in some other respiratory disorders. Typically, they are classified into two major classes, M1 and M2; however, recent findings have indicated that in fact there is a whole range of macrophage polarization and functional diversity beyond this bimodal division.
The present study aimed to investigate the immunostimulatory activities of polysaccharides purified from Glycyrrhiza glabra root. First, five polysaccharide fractions were separated from G. glabra through hot water extraction, ethanol precipitation, enzymatic hydrolysis, and size exclusion chromatography.
