Saitou M, Kida S, Kaise S, Suzuki S, Ohara M, Kasukawa R
Department of Internal Medicine II, Fukushima Medical College, Japan.
Fukushima J Med Sci. 1997 Dec;43(2):75-85.
The mechanism of bronchoobstruction in asthmatics following inhalation of lipopolysaccharide (LPS) is unclear.
In this study we have investigated the effects of the LPS on eosinophil survival rate in stimulating peripheral blood mononuclear cells (PBMCs) from patients with asthma.
PBMC supernatants from 10 asthmatic patients and 4 healthy subjects were compared for eosinophil survival rate using the same purified eosinophils. Two x 10(6) cells/ml of PBMCs were cultured for 24 hours in RPMI 1640 containing 10% fetal bovine serum along with 10 micrograms/ml of LPS. 10(6) cells/ml of eosinophils were incubated for 96 hours in the presence of PBMC-derived culture supernatants at 75% in volume.
The viability of eosinophils incubated with PBMC supernatants from asthmatic patients stimulated with LPS was higher, 62.5% +/- 10.6% (mean +/- SD), than that without LPS, 26.9% +/- 10.8%, and also higher than that of PBMCs from healthy subjects with LPS, 40.0% +/- 15.4%. This increasing activity of asthmatic PBMC stimulated with LPS was markedly inhibited from 72.2% +/- 9.7% to 38.5% +/- 6.8% by addition of mouse anti-human GM-CSF antibody to the PBMC supernatant but not mouse anti-human IL-5 antibody.
These results suggest that LPS enhances eosinophil survival in asthmatics by increasing the production of GM-CSF from PBMCs.
哮喘患者吸入脂多糖（LPS）后支气管阻塞的机制尚不清楚。
在本研究中，我们调查了LPS对哮喘患者外周血单核细胞（PBMCs）刺激嗜酸性粒细胞存活率的影响。
使用相同纯化的嗜酸性粒细胞，比较10例哮喘患者和4例健康受试者的PBMC上清液中嗜酸性粒细胞的存活率。将2×10⁶个细胞/ml的PBMCs在含有10%胎牛血清和10μg/ml LPS的RPMI 1640中培养24小时。将10⁶个细胞/ml的嗜酸性粒细胞在PBMC来源的培养上清液存在下，以75%的体积孵育96小时。
与用LPS刺激的哮喘患者的PBMC上清液孵育的嗜酸性粒细胞的活力较高，为62.5%±10.6%（平均值±标准差），高于未用LPS刺激的嗜酸性粒细胞的活力，即26.9%±10.8%，也高于用LPS刺激的健康受试者的PBMCs的嗜酸性粒细胞活力，即40.0%±15.4%。通过向PBMC上清液中加入小鼠抗人GM-CSF抗体，LPS刺激的哮喘PBMC的这种增强活性从72.2%±9.7%显著抑制至38.5%±6.8%，但加入小鼠抗人IL-5抗体则无此效果。
这些结果表明，LPS通过增加PBMCs中GM-CSF的产生来提高哮喘患者嗜酸性粒细胞的存活率。
