Pseudomonas aeruginosa infection in cystic fibrosis. Distribution of B and T lymphocytes in relation to the humoral immune response.

The influence of chronic Ps. aeruginosa infection on the occurrence of bone 
marrow-derived lymphocytes (B cells) and thymus-derived lymphocytes (T cells) in peripheral 
blood have been studied in 2 groups of patients with cystic 
fibrosis. One group (9 patients) suffered from chronic Ps. aeruginosa infection 
in the respiratory tract and produced multiple Ps. aeruginosa precipitins which 
were demonstrated by means of crossed immunoelectrophoresis. The other group (9 
patients) had never harboured Ps. aeruginosa in the respiratory tract and 
presented no demonstrable precipitins against this bacteria. The lymphocytes were examined 
for the presence of 2 surface markers for B cells: receptor 
for C3 complement component (EAC rosette-formation) and surface immunoglobulins (immunofluorescent staining), 
and for the presence of 1 surface marker for T cells: 
spontaneous binding of sheep red blood cells (E rosette-formation). The B:T 
cell ratio was nearly identical in the 2 groups of patients 
whereas the total numbers of B and T cells were significant 
higher in patients with chronic Ps. aeruginosa infection. The number of 
Ps. aeruginosa precipitins per serum was significantly positively correlated to the 
total number of T cells, wheras the correlation with the total 
number of B cells was insignificant. 