Identification and characterization of a homologue of the pro-inflammatory cytokine Macrophage Migration Inhibitory Factor in the tick, Amblyomma americanum.
Studying tick feeding and digestion, we discovered in a cDNA library from partially fed Amblyomma americanum ticks the first known arthropod homologue of a human cytokine, the pro-inflammatory Macrophage Migration Inhibitory Factor (MIF). The tick origin of the MIF cDNA clone was confirmed by sequencing a genomic fragment that contained the full-length tick MIF gene with two introns. Antiserum to a tick MIF-specific peptide as well as antiserum to complete tick MIF revealed the expression of tick MIF in the salivary gland and midgut tissues of A. americanum ticks. In an in vitro functional assay, recombinant tick MIF inhibited the migration of human macrophages to the same extent that recombinant human MIF did.
Jaworski
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DC
Department of Microbiology & Molecular Genetics, B240 Med Sci I, University of California-Irvine, Irvine, CA 92697, USA. djaworsk@uci.edu
Jasinskas
A
A
Metz
C N
CN
Bucala
R
R
Barbour
A G
AG
D000595:Amino Acid Sequence; D000818:Animals; D000918:Antibody Specificity; D060829:Arthropod Proteins; D001483:Base Sequence; D016207:Cytokines / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification / Q000502:physiology; D018076:DNA, Complementary; D005260:Female; D015870:Gene Expression; D006801:Humans; D008263:Macrophage Migration-Inhibitory Factors / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification / Q000502:physiology; D008264:Macrophages / Q000502:physiology; D008969:Molecular Sequence Data; D011817:Rabbits; D017386:Sequence Homology, Amino Acid; D013987:Ticks / Q000235:genetics* / Q000276:immunology; D014018:Tissue Distribution
D060829:Arthropod Proteins; D016207:Cytokines; D018076:DNA, Complementary; C437995:MIF protein, Amblyomma americanum; D008263:Macrophage Migration-Inhibitory Factors