Journal article
Leukocytes Infiltrate the Skin and Draining Lymph Nodes in Response to the Protozoan Leishmania infantum chagasi
Infection and immunity, Vol.79(1), pp.108-117
01/2011
DOI: 10.1128/IAI.00338-10
PMCID: PMC3019875
PMID: 20937764
Abstract
The vector-borne protozoan
Leishmania infantum chagasi
causes minimal inflammation after inoculation into skin but disseminates to cause fatal visceral leishmaniasis. To define the inflammatory response at the parasite inoculation site, we introduced metacyclic
L. infantum chagasi
promastigotes intradermally into BALB/c mouse ears and studied inflammatory cells over 7 days. Ly6G
+
neutrophils rapidly infiltrated the dermis, peaking after 6 to 24 h. Macrophages and NK cells next infiltrated the dermis, and NK followed by B cells expanded in draining lymph nodes. Parasite-containing phagocytes were tracked with fluorescent mCherry-labeled
L. infantum chagasi.
Ly6G
+
neutrophils contained the greatest proportion of intracellular parasites 6 to 24 h after inoculation, whereas dermal macrophages harbored the majority of intracellular parasites after 2 to 7 days. These observations were validated microscopically. Low doses of antibody transiently depleted mice of neutrophils, leaving other cells intact. Combined results of
in vivo
imaging, flow cytometry, and quantitative PCR showed that neutrophil depletion slowed the clearance of extracellular (luciferase-positive) promastigotes during the first 24 h after inoculation yet decreased the numbers of leukocytes containing intracellular (mCherry-positive) parasites. From 3 days onward, total
L. infantum chagasi-
containing dermal leukocytes and total
L. infantum chagasi
parasites in draining lymph nodes were similar in both groups. Nonetheless, a second wave of
L. infantum chagasi-
containing neutrophils occurred 7 days after parasite inoculation into neutrophil-depleted mice, corresponding to the time of neutrophil recovery. Thus, neutrophils were recruited to the dermis even late after inoculation, and
L. infantum chagasi
trafficked through neutrophils in both neutrophil-depleted and control mice, albeit with different kinetics. Recruitment of neutrophils and transient parasite residence in neutrophils may play a role in nonulcerative forms of leishmaniasis.
Details
- Title: Subtitle
- Leukocytes Infiltrate the Skin and Draining Lymph Nodes in Response to the Protozoan Leishmania infantum chagasi
- Creators
- Colin J Thalhofer - the Veterans Affairs Medical Center, Iowa City, Iowa 52242Yani Chen - the Veterans Affairs Medical Center, Iowa City, Iowa 52242Bayan Sudan - the Veterans Affairs Medical Center, Iowa City, Iowa 52242Laurie Love-Homan - the Veterans Affairs Medical Center, Iowa City, Iowa 52242Mary E Wilson - the Veterans Affairs Medical Center, Iowa City, Iowa 52242
- Resource Type
- Journal article
- Publication Details
- Infection and immunity, Vol.79(1), pp.108-117
- DOI
- 10.1128/IAI.00338-10
- PMID
- 20937764
- PMCID
- PMC3019875
- NLM abbreviation
- Infect Immun
- ISSN
- 0019-9567
- eISSN
- 1098-5522
- Publisher
- American Society for Microbiology (ASM)
- Language
- English
- Date published
- 01/2011
- Academic Unit
- Microbiology and Immunology; International Programs; Epidemiology; Internal Medicine
- Record Identifier
- 9984001148302771
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