Lymphocyte subsets in bronchoalveolar lavage fluid and in circulating blood in epidermoid bronchogenic carcinoma
G Piazza1, E Marchi, F Scaglione
1INRCA Pneumology Department, Casatenovo (Como), Italy.
Insights
Bronchogenic carcinoma patients show altered immune cells in bronchoalveolar lavage (BAL) fluid, not peripheral blood. Cigarette smoking significantly impacts lymphocyte subsets in BAL, suggesting a link to lung cancer development.
Area of Science:
- Immunology
- Oncology
- Pulmonology
Background:
- Assessing immune status in lung cancer patients is crucial for understanding disease progression and treatment efficacy.
- Investigating bronchoalveolar lavage (BAL) fluid and peripheral venous blood (PVB) offers insights into localized and systemic immunity.
- The influence of smoking on immune cell profiles in the respiratory tract requires further elucidation.
Purpose of the Study:
- To evaluate immune cell populations (lymphocytes, granulocytes) and subsets (OKT3+, OKT4+, OKT8+) in BAL fluid and PVB of lung cancer patients.
- To determine if immune alterations in the bronchoalveolar environment correlate with those in peripheral circulation.
- To explore the combined effects of neoplastic disease and smoking on the pulmonary immune system.
Main Methods:
- Bronchoalveolar lavage (BAL) was performed on 30 patients undergoing bronchoscopy for suspected lung cancer.
- Immune cell analysis included percentages of alveolar macrophages, lymphocytes, granulocytes, and specific T-cell subsets (OKT3+, OKT4+, OKT8+) and their ratios.
- Subjects were categorized into neoplastic and non-neoplastic groups, and further stratified by smoking status.
Main Results:
- Neoplastic patients exhibited a significant increase in OKT3+ and OKT8+ lymphocytes in BAL fluid compared to non-neoplastic subjects.
- No significant differences in immune cell profiles were observed in peripheral venous blood (PVB) between neoplastic and non-neoplastic groups.
- Smokers, regardless of cancer status, showed more pronounced alterations in lymphocyte subsets (decreased T4+, increased T8+, reduced T4/T8 ratio) in BAL fluid compared to non-smokers.
Conclusions:
- Peripheral blood immune markers are not reliable indicators of lung-specific immunity in bronchogenic neoplasia.
- Cigarette smoking independently and jointly contributes to immune dysregulation within the alveolar environment, potentially increasing lung cancer risk.
- Altered immune cell profiles in BAL fluid, particularly in smokers with lung cancer, highlight the complex interplay between smoking, immunity, and carcinogenesis.
Abstract:
Alveolar macrophages, lymphocyte and granulocyte percentages, together with OKT3+, OKT4+, OKT8+ lymphocyte subsets and OKT4+/OKT8+ ratio, were evaluated in bronchoalveolar lavage (BAL) fluid and in peripheral venous blood (PVB) of neoplastic and nonneoplastic subjects, in order to assess these aspects of immunity in neoplastic disease and to find out if the modifications in the bronchoalveolar environment are correlated to the ones in the circulation blood. BAL was performed in 30 patients undergoing fiberoptic bronchoscopy to ascertain the presence of lung cancer. Twelve of them had positive findings for epidermoid bronchogenic carcinoma, while in the remaining subjects the diagnosis was not confirmed. The 30 examined subjects were then grouped according to their smoking habit. In PVB, no significant difference was seen between neoplastic and nonneoplastic subjects, whereas in BAL the neoplastic patients showed a significant increase of lymphocytes OKT3+ and OKT8+. This tends to confirm that PVB is not a good indicator of organ immunity and may justify the reduced activity of alveolar macrophages in subjects affected by bronchogenic neoplasia. Between smokers and nonsmokers, lymphocyte subsets showed more significant differences than between neoplastic and nonneoplastic subjects (decrease of T4+ lymphocytes, increase of T8+ lymphocytes and, therefore, reduction of T4/T8 ratio); there were also scalar variations in the three groups (smokers with cancer, smokers without cancer and nonsmokers without cancer). Thus, the possible autonomous role of cigarette smoke and the presence of neoplasia in the immunity alterations of the alveolar environment with final joint effects were confirmed. These data may indicate a possible correlation between cigarette smoking, immunological alterations in BAL and the onset of bronchogenic carcinoma.
