Objectives: To determine which ‘site specific' chemokines are produced by epithelial cells in the oral mucosa.
Methods: Normal oral (NOK) and normal skin keratinocytes (NSK) were grown in vitro, RNA extracted and analysed by RT-PCR for CCL25, CCL27 and CCL28 mRNA. Expression of chemokine protein was analysed by immunocytochemistry using mouse anti-human CCL25, CCL27 and CCL28 primary antibodies on NOK and NSK cells in vitro and on tissue sections of normal oral mucosa and skin (n=5).
Results: NOK produced high levels of CCL25 and CCL28 and low levels of CCL27 mRNA and in contrast NSK produced high levels of CCL27, low levels of CCL28 and no CCL25 mRNA. This pattern was reflected in immunostaining of the epithelial cell in vitro and in vivo.
Conclusion: These results confirm that leukocyte migration into the skin is mediated by CCL27 and show for the first time that CCL25 and CCL28 play an important role in the oral cavity. This suggests the oral mucosa mimics the intestinal mucosa and salivary glands rather than the skin in terms of leukocyte migration mechanisms. Further work is required to determine whether these chemokines change in oral mucosal disease.
This project is funded by the Ministry of Higher Education of Saudi Arabia.