The identification, characterization, and distribution of guinea pig CCR4 and epitope mapping of a blocking antibody.
Th2 lymphocytes play a central role in the control and maintenance of allergic inflammation. The chemokine receptor CCR4 is preferentially expressed on the surface of Th2 lymphocytes polarised in vitro. However, CCR4 is found on the surface of a significant proportion of circulating memory T lymphocytes, some of which are capable of producing the Th1-associated cytokine interferon gamma. To investigate the function of CCR4 on guinea pig (gp) T lymphocytes, we identified the open-reading frame of gpCCR4, which encodes a 361-amino acid protein with 88 and 81% amino acid identity to human and murine CCR4 sequences, respectively. Cells transfected with gpCCR4 migrated toward the human and murine orthologues of the CCR4 ligands, macrophage-derived chemokine and thymus and activation-regulated chemokine. Surface expression of CCR4, using an anti-human CCR4 monoclonal antibody, 10E4, was detected on approximately 12% of guinea pig peripheral blood T helper cells, and CCR4(+) guinea pig thymocytes were detected in low numbers. However, CCR4(+) T helper cells constituted approximately 9% of the T lymphocyte population within the normal guinea pig lung and 52% of the guinea pig bronchoalveolar lavage fluid, which is consistent with a role for CCR4 in T lymphocyte development and trafficking through normal tissues. Subsequent analysis of chimeric chemokine receptors indicated that 10E4, a functional inhibitor of gpCCR4 responses, recognized the amino terminus of CCR4.
Jopling
Louise A
LA
Leukocyte Biology Section, Biomedical Sciences Division, Faculty of Medicine, Imperial College of Science, Technology and Medicine, Exhibition Road, London SW7 2AZ, United Kingdom.
Sabroe
Ian
I
Andrew
David P
DP
Mitchell
Tracey J
TJ
Li
You
Y
Hodge
Martin R
MR
Williams
Timothy J
TJ
Pease
James E
JE
D000595:Amino Acid Sequence; D000596:Amino Acids / Q000737:chemistry; D000818:Animals; D000911:Antibodies, Monoclonal / Q000378:metabolism; D001992:Bronchoalveolar Lavage Fluid; D002460:Cell Line; D002465:Cell Movement; D017124:Conserved Sequence; D004305:Dose-Response Relationship, Drug; D015536:Down-Regulation; D018604:Epitope Mapping; D005434:Flow Cytometry; D006031:Glycosylation; D006168:Guinea Pigs; D006801:Humans; D008024:Ligands; D008214:Lymphocytes / Q000378:metabolism; D051379:Mice; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D017434:Protein Structure, Tertiary; D011869:Radioligand Assay; D054398:Receptors, CCR4; D019707:Receptors, Chemokine; D017386:Sequence Homology, Amino Acid; D018418:Th2 Cells; D014018:Tissue Distribution; D014157:Transcription Factors / Q000096:biosynthesis* / Q000737:chemistry* / Q000378:metabolism; D014162:Transfection
D000596:Amino Acids; D000911:Antibodies, Monoclonal; C515354:CCR4 protein, human; C515355:Ccr4 protein, mouse; D008024:Ligands; D054398:Receptors, CCR4; D019707:Receptors, Chemokine; D014157:Transcription Factors