Alpha 1-antitrypsin and alpha 1-acid glycoprotein reduce the sensitivity of human dermal fibroblast to endotoxin.
OBJECTIVE
To test the hypothesis that acute phase reactants, such as alpha 1-antitrypsin and alpha 1-acid glycoprotein, could protect mammalian cells from further damage.


METHODS
Human dermal fibroblasts (5 x 10(4)) were cultured with DMEM plus 10% FBS at 37 degrees C in a 5% CO(2) incubator. Different doses of LPS (lipo polysaccharide) and/or acute phase reactants were added. After 24 hours, the cultured supernatant was aspirated, the cells were washed, fixed and stained by methylene blue. The unbound stain was washed off. The stained cells were solubilize d in 0.1 ml of 1% Triton X-100. The absorbance of each well was measured us ing an ELISA spectrophotometer. The concentration of LPS which decreased the absorbance to 70% of the control (LPS-free) cultures was defined as LD(30).


RESULTS
In order to achieve LD(30) in the presence of acute phase proteins, it was necessary to alter the LPS concentrations. The LD(3 0) of LPS treated with 0, 0.5, 2, 10 mg/ml antitrypsin and 0, 0.5, 2, 10 mg/ml glycoprotein was 5.4, 6.5, 7.6, 14.2 mg/ml and 5.2, 5.9, 6.9, 10.5 mg/ml, respectively. Statistically, with the treatment of more than 2 mg/ml antitrypsin or glycoprotein, LD(30) increased significantly.


CONCLUSIONS
Our data show that fibroblasts are susceptible to the direct toxicity of LPS. Alpha 1-antitrypsin and alpha 1-acid glycoprotein can reduce the toxicity and/or increase the tolerance of mammalian cells to LP S.
Xia
Z
Z
Burns Center, Changhai Hospital, the Second Military Medical University, Shanghai 200433, China.
Wang
G
G
Ge
S
S
Tian
J
J
D000210:Acute-Phase Reaction / Q000503:physiopathology; D002478:Cells, Cultured; D005347:Fibroblasts / Q000187:drug effects*; D006801:Humans; D008070:Lipopolysaccharides; D009961:Orosomucoid / Q000494:pharmacology*; D000515:alpha 1-Antitrypsin / Q000494:pharmacology*
D008070:Lipopolysaccharides; D009961:Orosomucoid; D000515:alpha 1-Antitrypsin