Reduced expression of the chemokine receptor CCR1 in human macrophages and U-937 cells in vitro infected with Leishmania infantum.
Chemokines exert their actions through G-proteinlinked receptors, which are expressed to variable extents by different cell types. In accordance with the chemokine classification, these receptors are designated as CXC, CC, XC, and CX(3)C, followed by R and a number. The purpose of this investigation was to evaluate CCR1 expression in human peripheral blood-derived macrophages and the human monocytic U-937 cell line. Cells in vitro were infected with live Leishmania infantum promastigotes (zymodeme MON1); cell lysates were then subjected to SDS-PAGE and immunoblotting, by using an anti-CCR1 affinity purified polyclonal antibody. The expression of the CCR1 gene was analyzed by RT-PCR, using specific human primers. The results of both immunoblotting and RT-PCR showed that CCR1 expression in Leishmania-infected cells was lower than in uninfected control cells. These results indicate that Leishmania infantum infection causes a down-regulation of the CCR1 gene and protein expression, suggesting that reduced phagocyte recruitment at the inflammation sites could favor parasite progression and the spread of Leishmania infection.
Panaro
M A
MA
Department of Human Anatomy and Histology, University of Bari, I-70124, Bari, Italy, ma.panaro@anatomia.uniba.it
Spinelli
R
R
Lisi
S
S
Sisto
M
M
Acquafredda
A
A
Fumarola
L
L
Mitolo
V
V
Brandonisio
O
O
D000818:Animals; D015153:Blotting, Western; D003720:Densitometry; D005786:Gene Expression Regulation; D006801:Humans; D018314:Leishmania infantum / Q000502:physiology*; D008264:Macrophages / Q000378:metabolism* / Q000469:parasitology*; D054389:Receptors, CCR1; D019707:Receptors, Chemokine / Q000096:biosynthesis* / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D020298:U937 Cells
C515300:CCR1 protein, human; D054389:Receptors, CCR1; D019707:Receptors, Chemokine