Zymosan-activated macrophages

Investigation of a partially purified particulate gluean preparation from Saccharomyces cerevisiae cell walls has expanded. Glucan is held re-sponsil le for most of the reticuloendothelial-stimulating properties of zymosan. The preparation was reported to activate macrophages as assessed by... 

Merck s L-651,896 (54) was the lead compound from a series of dihydro-benzofuranols [158]. L-651,896 inhibited cRBL (1 //M) as well as platelet 12-LO (5.9 /zM). In zymosan-stimulated mouse macrophages, both LTC4 and PGE2 release were inhibited (0.1 //M and 1.1 //M, respectively) similar potency was seen in rat and human ISN. Potent topical activity in AAE was seen, with LT production and oedema both inhibited at 20-30 nM/ear. LT levels were also reduced in mouse oxazolone contact sensitivity, but in this... 

Other compounds containing heteroatom-heteroatom bonds have been reported as 5-LO inhibitors. Diphenyldisulphides and substituted analogues, as well as disulphiram (108), inhibited cRBL and LT release from zymosan-stimulated mouse macrophages (0.3-20 / M) [277, 278]. A number of thiosulphinate esters such as (109) and related compounds, isolated from onion and garlic, were likewise active in cells and cell-free enzymes over the... 

The preincubation with Pycnogenol has been reported to significantly decrease the extent of the oxidative burst induced by zymosan treatment in a dose-dependent manner in the murine macrophage cell line J774. This observation corroborates a possible beneficial role for Pycnogenol on the modulation of macrophage activity and on chronic inflammatory conditions. ... 

In addition to phagocytosis and release of different kinds of prostaglandins and hydrolytic enzymes [321,322], macrophages have an important role in the initiation of the cell-mediated immune reaction in response to the antigen presented. The cells are activated by a variety of agents such as immune complexes, lymphokines, zymosane and C3b. 

Rankin, J. A., Sylvester, 1., Smith, S., Yoshimura, T., and Leonard, E. J. (1990) Macrophages cultured in vitro release leukotriene B4 and neutrophil attractant/activation protein (Interleukin 8) sequentially in response to stimulation with lipopolysaccharide and zymosan. 7. Clin. Invest. 86,1556-1564. 

Tetrandrine was a potent inhibitor in vitro of zymosan-stimulated oxygen consumption, superoxide anion release, and hydrogen peroxide secretion by rat alveolar macrophages (Castranova et al. 1991). Tetrandrine (33 pg/kgxday) was also effective in vivo in preventing activation of alveolar macrophages after inhalation (117.5 12.5 mg/m of 1.5410.01 im mass median diameter for 6 h per day) or intratracheal instillation (40 mg in 0.3 ml of saline, specific surface 3.97 mVg) silica. Tetrandrine also inhibited stimulant-induced chemiluminescence by polymorphonuclear leucocytes. 

Zymosan-bound histamine activated Oj formation in guinea pig alveolar macrophages via HI receptors (Diaz et al. 1979). 

Formation of oxygen radicals has been demonstrated with human granulocytes and macrophages from mice by the chemiluminescence method. After 60 min preincubation with 50 Lig/ml expressed sap and suboptimal stimulation by Zymosan, a significant stimulation of granulocyte activity of 24% was observed [142, 143]. 

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