Chemokine expression and leucocyte infiltration in Sjögren's syndrome.
OBJECTIVE
To investigate the expression and source of chemokines in minor salivary gland biopsies (MSGs) in patients with Sjögren's syndrome (SS).


METHODS
Immunohistochemical analysis was used to determine the pattern of chemokine expression in MSGs from patients with (n=6) and without (n=5) SS, as well as to examine the phenotype of both resident and infiltrating cells expressing chemokines.


RESULTS
Significant differences in the number of infiltrating mononuclear (MN) cells in patients with and without SS were noted. Ductal epithelial cells of SS biopsies expressed significantly increased levels of macrophage inflammatory protein (MIP)-1alpha, MIP-1beta, interleukin-8 (IL-8) and RANTES (Regulated upon Activation, Normal T cell Expressed and Secreted). Biopsies from patients with SS showed that MIP-1beta was expressed by 51% of infiltrating cells, while 41% expressed MIP-1alpha, whereas 22 and 7% expressed RANTES and IL-8, respectively.


CONCLUSIONS
Chemokines expressed by ductal epithelial cells may attract circulating leucocytes, in particular CD4+ T cells, towards the site of inflammation, thereby orchestrating the influx of MN cells characteristically seen in MSGs in SS. Chemokines may be induced directly by a putative triggering agent for SS, or secondary to the release of pro-inflammatory cytokines produced by epithelial cells. These findings further implicate epithelial cells as playing a major role in the pathogenesis of SS and implicate chemokines in the leucocyte recruitment in this setting.
Cuello
C
C
Inflammation Research Unit, School of Pathology, The University of New South Wales, Sydney, Australia.
Palladinetti
P
P
Tedla
N
N
Di Girolamo
N
N
Lloyd
A R
AR
McCluskey
P J
PJ
Wakefield
D
D
D002452:Cell Count; D002465:Cell Movement; D054405:Chemokine CCL3; D054407:Chemokine CCL4; D018946:Chemokine CCL5 / Q000378:metabolism; D018925:Chemokines / Q000378:metabolism*; D004847:Epithelial Cells / Q000378:metabolism; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D016209:Interleukin-8 / Q000378:metabolism; D007963:Leukocytes, Mononuclear / Q000473:pathology*; D019402:Macrophage Inflammatory Proteins / Q000378:metabolism; D012470:Salivary Glands, Minor / Q000378:metabolism* / Q000473:pathology; D012859:Sjogren's Syndrome / Q000378:metabolism* / Q000473:pathology
D054405:Chemokine CCL3; D054407:Chemokine CCL4; D018946:Chemokine CCL5; D018925:Chemokines; D016209:Interleukin-8; D019402:Macrophage Inflammatory Proteins