Eosinophils and monocytes produce pulmonary and activation-regulated chemokine, which activates cultured monocytes/macrophages
| Autor: | Ingrid U. Schraufstatter, P. Sriramarao, Hiroshi Takamori, Richard G. DiScipio, Lyudmila Sikora |
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| Rok vydání: | 2004 |
| Předmět: |
Pulmonary and Respiratory Medicine
Chemokine Polymers Physiology Gene Expression CC chemokine Enzyme-Linked Immunosorbent Assay Monocytes Physiology (medical) Escherichia coli medicine Humans Monocytes macrophages heterocyclic compounds RNA Messenger Cells Cultured Gene Library biology Monocyte CCL18 Cell Biology biochemical phenomena metabolism and nutrition bacterial infections and mycoses Actins Sequence identity Eosinophils Chemotaxis Leukocyte medicine.anatomical_structure Chemokines CC Immunology biology.protein bacteria Calcium |
| Zdroj: | American Journal of Physiology-Lung Cellular and Molecular Physiology. 286:L494-L501 |
| ISSN: | 1522-1504 1040-0605 |
| DOI: | 10.1152/ajplung.00323.2002 |
| Popis: | Pulmonary and activation-regulated chemokine (PARC/CCL18) belongs to the family of CC chemokines and shares 61% sequence identity with monocyte inflammatory protein (MIP)-1α. Produced by dendritic cells and macrophages primarily in the lung, PARC is known to be chemotactic for T cells. Because PARC's biological function is largely unknown, we screened various leukocyte populations for PARC expression and for response to PARC, with the idea that the cellular source may link PARC to disease states in which it may be involved. Here we report that eosinophils obtained from individuals with mild eosinophilia express PARC as assessed by RT-PCR on eosinophil RNA. The eosinophil preparations were free of monocytes, a known source of PARC, and no RT-PCR product was obtained from neutrophils. Furthermore, PARC protein was detected by ELISA in the supernatants of eosinophils from seven of nine donors and in higher concentration in the supernatants of monocytes on day 1 of culture. Purified recombinant PARC activated human monocytes/macrophages kept in culture for 3-4 days but not freshly isolated monocytes. The threshold dose for Ca2+mobilization as determined fluorometrically in indo 1-AM-labeled monocytes was 5 nM; maximal response was reached with ∼50 nM PARC. PARC was chemotactic for these cultured monocytes and caused actin polymerization determined by FITC-phalloidin binding and fluorescence-activated cell sorting analysis. In contrast, PARC activated neither neutrophils nor eosinophils. Eosinophil production of PARC, its chemotactic effect on monocytes and lymphocytes, and PARC's previously described localization to the lung suggest that this chemokine might play a role in pulmonary leukocyte trafficking. |
| Databáze: | OpenAIRE |
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