Objective: To investigate the clinical value of peripheral blood lymphocytes immunophenotyping and Natural Killer cells (NK) in the judgment of the types of Connective Tissue Disease Combined with Interstitial Lung Disease (CTD-ILD).
Methods: 262 CTD-ILD patients and 50 healthy volunteers in our hospital from January 2010 to December 2015 were enrolled into the study. There were 164 patients with CTD-ILD and 98 patients with ILD. The clinical symptoms and High Resolution CT (HRCT) of all patients were observed and compared between the two groups. The serum levels of CD3+, CD4+, CD8+, CD19+, CD56+ T cells were detected by flow cytometry and compared among the three groups.
Results: There were no difference of the clinical symptoms and the characteristics of HRCT between the two patients groups (P>0.05). The serum level of CD3+-CD8+ T cells of patients in the CTD-ILD group was higher than the control group and ILD group (P<0.05); and the serum level of CD3-CD56+ T cells and the ratio of CD4+/CD8+ in the CTD-ILD group was lower than the control group and ILD group (P<0.05). But there was no difference of the peripheral blood lymphocytes immunophenotyping between the ILD group and control group (P>0.05).
Conclusion: The immunophenotype of peripheral blood lymphocytes could be helpful to judge the types of connective tissue disease combined with interstitial lung disease.