[Effect of adenosine and anti-IgE antibody on histamine release from mast cells in BALF of asthma patients].

AIM

To investigate the functional properties of mast cells in bronchoalveolar lavage fluid (BALF) of asthma patients.

METHODS

29 asthma patients in the recovery phase were enrolled in the study and their bronchoalveolar lavages (BAL) were inspected under fibreoptics bronchoscope. The cells from each BAL fluid(BALF) were added to LP4 tubes containing anti-IgE antibody, adenosine, buffer or anti-IgE antibody + adenosine, and incubated at 37 degrees C for 20 min. The reactions were stopped by placing the tubes on ice and adding 100 microL of cold incomplete Hank's balanced salt solution (HBSS). The histamine chromogenic assay was performed to detect histamine released from mast cells in BALF. Histamine release was expressed in a net release percentage.

RESULTS

100 micromol/L of adenosine failed to induce histamine release from mast cells; while 1,000 micromol/L of adenosine could induce about 17% histamine release from mast cells in BALF; For anti-IgE antibody, as low as 1 x 10(-4) g/L of anti-IgE was able to induce approximately 20% histamine release from the mast cells. When the anti-IgE antibody was combined with adenosine, only 3 x 10(-5) g/L of anti-IgE antibody + adenosine could exert synergistic effectiveness.

CONCLUSION

Mast cells in BALF from asthma patients had a poor reaction to adenosine stimulation,but are much more sensitive to anti-IgE antibody-dependent stimulation; only as low as 3 x 10(-5) g/L of anti-IgE antibody is able to cooperate with adenosine.