RESUMO
Objective:Accumulating evidences prove that macrophages affect tumor initiation and prognosis. Especially,tumor-associated macrophages (TAMs) are considered to enhance tumor growth,progression,angiogenesis,invasion and metastasis. Furthermore,tumor suppressive microenvironment can " reeducate" and polarize the phenotype and function of TAM. Recently, researchers use different ways to interfere and modify the phenotype and function of macrophages,to improve the recognition, phagocytosis and antigen presentation of macrophage,and enhance its antitumor activity. We will discuss the pro-tumorigenic properties of macrophage and TAM-targeting therapy as a promising novel strategy for tumor immunotherapy.
RESUMO
Conditions about protoplast preparation and regeneration of Streptococcus zooepidemicus,which could produce hyaluronic acid, were studied , including the concentration of lysozyme, lytic time, different osmotic stabilizers and the preculture under the high osmotic pressure . As a result, the formation and regeneration rate of protoplasts could reach up to 94.6% and 18.5% respectively under the optimum conditions, before the digestion of lysozyme (50U/mL,39℃, 60 min) the strain was cultured for 2 hours in 0.6 mol/L NaCl high osmotic pressure liquid medium containing 1.2% Gly. Among different treatments of various laser power and irradiating time, He-Ne laser which acted for 300 seconds with 40mW /cm 2 caused lethality rate as high as 99.88%. Finally, a mutated strain was gained, whose production of HA is 2.21g/L, just 4.5 times as much as the original strain.