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Background: CC chemokine ligand (CCL)5 and its receptor CCR5 contribute to leukocyte migration into lungs of patients with diffuse lung diseases (DLD). Pharmacological regulation of CCL5 and CCR5 expression was therefore explored in bronchoalveolar cells obtained from patients with DLD., Methods: Cells from 21 patients were co-cultivated in vitro with tumour necrosis factor-alpha and dexamethasone, cyclosporin A (CyA) or pentoxifylline. Chemokine mRNA expression and protein production was assessed by reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay, respectively., Results: Dexamethasone altered CCL5 mRNA expression and suppressed its protein levels. CyA inhibited chemokine mRNA expression but not protein production. Pentoxifylline did not affected chemokine expression. Both dexamethasone and CyA suppressed CCR5 mRNA transcripts., Conclusion: In conclusion, while dexamethasone downregulates the CCL5 functional form, CyA and pentoxifylline have no effects on CCL5 protein. These data provide in vitro correlation for clinical applications of immunomodulators in therapy of DLD.

In this study, messenger RNA (mRNA) expression for novel T lymphocyte chemoattractants, leukotactin-1, macrophage inflammatory protein (MIP)-3 alpha and MIP-3 beta was investigated in bronchoalveolar lavage fluid (BALF) cells from patients with sarcoidosis, a T cell-mediated disease with typical CD4+ lymphocyte alveolitis. Of these three chemokines, only MIP-3 beta mRNA was upregulated in sarcoidosis, and therefore, protein levels of this chemokine, its pharmacologic regulation, and association with disease clinical course were explored. MIP-3 beta protein concentrations were elevated in BALF from sarcoid patients compared with control subjects (p = 0.001) and in patients with chest X-ray stage II chemokine protein levels were increased compared with stage I (p = 0.003). MIP-3 beta protein was associated predominantly with alveolar macrophages and correlated with BALF lymphocytes and T cell subsets. mRNA expression for the MIP-3 beta receptor, CC chemokine receptor 7, was increased in sarcoidosis and correlated with MIP-3 beta protein levels. MIP-3 beta mRNA and protein expression in BALF cells was suppressed by dexamethasone and cyclosporine A in vitro. In conclusion, MIP-3 beta is implicated in T lymphocyte recruitment in sarcoidosis, is associated with disease progression, and is downregulated by drugs used for sarcoidosis treatment. This novel chemokine, therefore, represents a candidate for studies of sarcoidosis pathobiologic mechanisms.

The CC chemokine receptor 5 (CCR5) binds the chemokine ligands RANTES (CCL5) and MIP-1alpha (CCL3), which have been implicated in the development of alveolitis in sarcoidosis. We have, therefore, investigated CCR5 mRNA expression in bronchoalveolar lavage fluid (BALF) cells from patients with sarcoidosis. Further, we explored whether there was any association between CCR5 mRNA expression and the presence of the CCR5Delta32 DNA polymorphism. Semiquantitative RT-PCR was used to determine CCR5 mRNA expression from BALF cells from 16 control subjects (C) and 39 patients with sarcoidosis (S). The data on the CCR5Delta32 polymorphism, determined by PCR-SSP, were available for 37 patients. CCR5 mRNA expression was significantly upregulated in sarcoidosis (median+/-SEM, C, 0.00+/-0.07; S, 0.12+/-0.07; P<0.05). When patients were evaluated according to their CCR5Delta32 genotype, an interesting trend emerged with Delta32 positive patients (wt, mt) expressing less mRNA than the patients with both wild-type alleles (wt, wt): 0.00+/-0.09, and 0.26+/-0.09, respectively; P>0.05). In conclusion, upregulation of CCR5 mRNA in BALF of patients with sarcoidosis is consistent with its chemokine ligands RANTES and MIP-1alpha playing a pivotal role in inflammatory cell recruitment to disease sites. Though the data from this pilot study had no clinical correlations we suggest that further studies are warranted on the role of this Th1 subset marker in the pathogenesis of sarcoidosis.