The effect of cigarette tobacco extract exposure on the blood neutrophils metabolic activity in patients with COPD

Yupatova T.G., Ishchenko O.V.

Vitebsk State Medical University, Vitebsk, Belarus

The purpose of the study was to investigate influence of 1% cigarette tobacco extract (CTE) exposure on the blood neutrophils metabolic activity in the reaction of nitrotetrazolium blue reduction (NBT-test).
Material and methods. We have examined 14 patients with chronic obstructive pulmonary disease (COPD by GOLD critera) with an infectious exacerbation. The control group consisted of 13 healthy individuals with normal pulmonary function. The venous blood from 7 patients was obtained in the morning on the first day of hospital admission. The venous blood of another 7 patients was obtained after 4-6 days of admission.We estimated spontaneous metabolic activity of neutrophils (spontaneous NBT-test) with physiological solution. To determine stimulated NBT-test we used 1% CTE or a suspension of killed Staphylococcus aureus. All samples were incubated at 37оC for 15 minutes and subsequently kept at room temperature for an additional 15 minutes. The ready smears were examined under the microscope with oil immersion with counting the amount of formazan-positive granulocytes in the NBT-test. 200 neutrophils were examined for cells containing dark deposits of formazan.
Results. We determined that percentage of NBT-positive blood neutrophils in patients with COPD was increased in the spontaneous NBT-test in beginning of infectious exacerbation compared with the control group (р<0,001). Incubation with CTE reduced the blood neutrophils metabolic activity in patients with COPD in the induced NBT-test compared to the spontaneous NBT-test (p=0,001) in the beginning of exacerbation. CTE did not affect blood neutrophils metabolic activity in patients after 4-6 days of hospitalization (p=0,3) and healthy individuals (p=0,08). We did not determine disturbance of blood neutrophils metabolic activity in patients with COPD compared with control group after stimulation by a suspension of killed Staphylococcus aureus.
Conclusions. The percentage of NBT-positive blood neutrophils of patients with COPD is increased in the spontaneous NBT-test in the beginning of infectious exacerbation. Incubation with 1% cigarette tobacco extract reduced the blood neutrophils metabolic activity in patients with COPD in the beginning of exacerbation. NBT-test with CTE is recommended for patients with COPD during infectious exacerbation for planning the management strategy and predicting the outcome of the disease.