Spleen, macrophages

Conventional liposomes and lipid complexes. Liposomes were used initially as a model system for cellular membranes to study the biochemistry of membrane proteins.85 Consequently, when liposomes were first tried as a drug delivery system, their bilayers were composed of un-derivatized naturally occurring lipids. Most of such conventional liposomes are taken up by the MPS phagocytes within a few hours of injection, mostly by liver Kupffer cells and spleen macrophages.9 Inside the endosomes and lysosomes of those cells, liposomes are degraded. If the liposomal drugs are membrane permeable, they then can diffuse from the endosomal compartments to the cytoplasm of the macrophage cells and slowly reenter the blood circulation. Because such a clearance... 

Schipper et al. also conducted a pilot toxicologic study of the covalently and noncovalently PEG-functionalized SWNTs in mice.123 Their results suggested that the functionalized SWNTs persisted within liver and spleen macrophages for four months without apparent toxicity.123... 

Lolait SJ, Lim AT, Toll BH, Funder JW (1984) immunoreaedve beta-endorphin in a subpopuladon of mouse spleen macrophages. J Clin hwest 73 277-280. 

Enose Y, Destache CJ, Mack AL, Anderson JR, Ullrich F, Ciborowski PS, Gendehnan HE (2005) Proteomic fingerprints distinguish microglia, bone marrow, and spleen macrophage populations. Glia 51 161-172. 

Sievers, J., Schmidtmayer, J., and Parwaresch, R., Blood monocytes and spleen macrophages differentiate into microglia-like cells when cultured on astrocytes, Ann. Anat., 176, 45, 1994. 

The tenacious recycling of iron is a function of macrophages that selectively remove from circulation the senescent red blood cells at the speed of 3-4 million cells per second [4]. This function is exercised mostly by spleen macrophages securing the remarkable constancy of erythrocyte parameters dependent on iron levels responsible for an adequate oxygen delivery, including for instance, cell numbers, mean corpuscular volmne (MCV), and mean hemoglobin concentration. 

Studies in weaning rats, in which the spleen was stained with the Prussian blue technique, indicate that the uptake of hemosiderin by splenic macrophage does not occur until adult-age histological development is achieved (58-60 days postpartum). Moreover, the ability of the spleen macrophage to store iron increases with the age of the animal. 

The phagocytic function of liver and spleen macrophages measured in vivo by the kinetics of blood clearance of colloidal carbon is similar in both lines (phagocytic index = 0.015 0.005 and 0.020 0.006 in High and Low line... 

The results reported on Figure 5.10 show that the persistence of the immunogenicity of SE in the spleen macrophages is much longer in High than in Low responders. 

Spleen macrophages and that their antigens persist in these cells since no significant amounts of antigen could be demonstrated in antibody synthesizing cells ... 

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