Osteoclastogenesis during infective exacerbations in patients with cystic fibrosis.
BACKGROUND
Adults with cystic fibrosis (CF) are at increased risk of developing osteoporosis. During infective exacerbations, increased production of proinflammatory cytokines and markers of bone resorption have been reported.


OBJECTIVE
The aim of this study is to investigate the growth and proliferation of potential osteoclast precursor cells before, during, and after intravenous antibiotic treatment of infective exacerbations in patients with CF.


METHODS
Hematopoietic precursor cell growth was examined using colony formation assays using Methocult culture medium. Circulating potential osteoclast precursors were identified using four-color flow cytometry by CD14, CD33, CD34, and CD45 expression.


RESULTS
At the start of an infective exacerbation increases in hematopoietic precursor colony formation (15.42 colonies/10(5) cells plated, p = 0.025), proliferation (28.5%, p < 0.001), and the numbers of circulating potential osteoclast precursors (6.5%, p < 0.001) were seen in comparison with baseline levels. These increases declined after treatment with intravenous antibiotics to a level close to baseline.


CONCLUSIONS
The results demonstrate an increase in the production of potential osteoclast precursors in the peripheral blood during CF infective exacerbations. This may result in increased bone resorption and contribute to bone loss in patients with CF.
Shead
Elizabeth F
EF
Department of Haematology, NHS Foundation Trust, Addenbrooke's Hospital, Cambridge, United Kingdom. lizzshead@hotmail.com
Haworth
Charles S
CS
Gunn
Elaine
E
Bilton
Diana
D
Scott
Mike A
MA
Compston
Juliet E
JE