Decreased T lymphocyte infiltration in bronchial biopsies of subjects with severe chronic obstructive pulmonary disease.
BACKGROUND
Studies on the inflammatory process in the large airways of patients with mild/moderate COPD have shown a prevalent T lymphocyte and macrophage infiltration of the bronchial mucosa. However, bronchial inflammation in more severe disease has not been extensively studied.


OBJECTIVE
The aim of the present study was to characterize the lymphocyte infiltration in the bronchial mucosa of subjects with severe, compared to mild, COPD, and to examine the relationship between airflow limitation and T lymphocyte numbers in the bronchial mucosa.


METHODS
We examined bronchial biopsies obtained from nine smokers with severe airflow limitation, nine smokers with mild/moderate airflow limitation and 14 smokers with normal lung function. Immunohistochemical methods on cryostat sections were used to assess the number of CD3+, CD4+, CD8+ cells and the number of CD3+ cells coexpressing the chemokine receptor CCR5 (CCR5+CD3+) in the subepithelium.


RESULTS
Subjects with severe COPD had lower numbers of CD3+, CD8+ and CCR5+CD3+ cells than mild/moderate COPD (P < 0.012, P < 0.02 and P < 0.02, respectively) and control smokers (P < 0.015, P < 0.005 and P < 0.015, respectively). In subjects with airflow limitation the number of CD3+ and CD8+ cells was inversely correlated with the degree of airway obstruction (r = 0.59, P < 0.015 and r = 0.52, P < 0.032, respectively).


CONCLUSIONS
Bronchial inflammation in severe COPD is characterized by lower numbers of CD3+ and CD8+ cells and decreased numbers of CD3+ cells coexpressing the chemokine receptor CCR5. T lymphocyte infiltration is inversely correlated with the degree of airflow limitation.
Di Stefano
A
A
Salvatore Maugeri Foundation, IRCCS, Medical Center of Rehabilitation, Division of Pulmonary Disease, Veruno, Italy. adistefano@fsm.it
Capelli
A
A
Lusuardi
M
M
Caramori
G
G
Balbo
P
P
Ioli
F
F
Sacco
S
S
Gnemmi
I
I
Brun
P
P
Adcock
I M
IM
Balbi
B
B
Barnes
P J
PJ
Chung
K F
KF
Donner
C F
CF
D000368:Aged; D001706:Biopsy; D015153:Blotting, Western; D001980:Bronchi / Q000378:metabolism* / Q000473:pathology*; D017252:CD3 Complex / Q000032:analysis; D016827:CD8 Antigens / Q000032:analysis; D002465:Cell Movement; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D007150:Immunohistochemistry; D008173:Lung Diseases, Obstructive / Q000453:epidemiology / Q000378:metabolism* / Q000473:pathology*; D018655:Lymphocyte Count; D008297:Male; D008875:Middle Aged; D019713:Receptors, CCR5 / Q000032:analysis; D012720:Severity of Illness Index; D012907:Smoking / Q000378:metabolism / Q000473:pathology; D013223:Statistics as Topic; D013601:T-Lymphocytes / Q000166:cytology* / Q000276:immunology
D017252:CD3 Complex; D016827:CD8 Antigens; D019713:Receptors, CCR5