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Transcriptional signatures of BALB/c mouse macrophages housing multiplying Leishmania amazonensis amastigotes.

Osorio y Fortéa J, de La Llave E, Regnault B, Coppée JY, Milon G, Lang T, Prina E - BMC Genomics (2009)

Bottom Line: A total of 1,248 probe-sets showed significant differential expression.Our findings suggest that the amastigote growth relies on early coordinated gene expression of the MPhi lipid and polyamine pathways.Moreover, these MPhi hosting multiplying L. amazonensis amastigotes display a transcriptional profile biased towards parasite-and host tissue-protective processes.

View Article: PubMed Central - HTML - PubMed

Affiliation: Institut Pasteur, Unité d'Immunophysiologie et Parasitisme Intracellulaire, Département de Parasitologie et Mycologie, Paris, France. josorio@pasteur.fr

ABSTRACT

Background: Mammal macrophages (MPhi) display a wide range of functions which contribute to surveying and maintaining tissue integrity. One such function is phagocytosis, a process known to be subverted by parasites like Leishmania (L). Indeed, the intracellular development of L. amazonensis amastigote relies on the biogenesis and dynamic remodelling of a phagolysosome, termed the parasitophorous vacuole, primarily within dermal MPhi.

Results: Using BALB/c mouse bone marrow-derived MPhi loaded or not with amastigotes, we analyzed the transcriptional signatures of MPhi 24 h later, when the amastigote population was growing. Total RNA from MPhi cultures were processed and hybridized onto Affymetrix Mouse430_2 GeneChips, and some transcripts were also analyzed by Real-Time quantitative PCR (RTQPCR). A total of 1,248 probe-sets showed significant differential expression. Comparable fold-change values were obtained between the Affymetrix technology and the RTQPCR method. Ingenuity Pathway Analysis software pinpointed the up-regulation of the sterol biosynthesis pathway (p-value = 1.31e-02) involving several genes (1.95 to 4.30 fold change values), and the modulation of various genes involved in polyamine synthesis and in pro/counter-inflammatory signalling.

Conclusion: Our findings suggest that the amastigote growth relies on early coordinated gene expression of the MPhi lipid and polyamine pathways. Moreover, these MPhi hosting multiplying L. amazonensis amastigotes display a transcriptional profile biased towards parasite-and host tissue-protective processes.

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Related in: MedlinePlus

Affymetrix outcome. A: Volcano plot. 1,248 probe-sets showed differential expression at the 0.05 threshold (green line): 605 positive and 643 negative FC values of which 454 in the right and 507 in the left upper corners (± 1.75 FC threshold, red lines, blue circles). B: Fold-change distribution of the 1,248 probe sets.
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Figure 2: Affymetrix outcome. A: Volcano plot. 1,248 probe-sets showed differential expression at the 0.05 threshold (green line): 605 positive and 643 negative FC values of which 454 in the right and 507 in the left upper corners (± 1.75 FC threshold, red lines, blue circles). B: Fold-change distribution of the 1,248 probe sets.

Mentions: L. amazonensis amastigotes subvert MΦ as host cells where they enter a cell-cycling phase lasting several days (Fig. 1A). We compared the transcriptomes of amastigote-free MΦ and amastigote-harbouring MΦ 24 h after the uptake of amastigotes carefully purified from nude mouse lesions. At this time-point amastigotes were multiplying within a huge PV (Fig. 1B) and their population size had almost doubled (Fig. 1A). Among the 45,101 probe-sets of the Mouse430_2 GeneChip, 1,248 (2.77%) were displaying features of differential expression at the 5% significance level (Fig. 2, see Additional file 1). Of these, 1,206 matched Ingenuity Pathway Analysis database version 5.5.1 which represented 898 genes with a known function. About 80% of these genes were incorporated into either Ingenuity's canonical pathway or biological network (i.e. their products interact with other molecules in Ingenuity's knowledge base). The symbols of the modulated genes are specified in the text (fold change [FC] values between brackets), while their full names are given in Additional file 1. Furthermore, comparable FC values were obtained between the Affymetrix technology and the Real Time quantitative Polymerase Chain Reaction (RTQPCR) method (Table 1) [3].


Transcriptional signatures of BALB/c mouse macrophages housing multiplying Leishmania amazonensis amastigotes.

Osorio y Fortéa J, de La Llave E, Regnault B, Coppée JY, Milon G, Lang T, Prina E - BMC Genomics (2009)

Affymetrix outcome. A: Volcano plot. 1,248 probe-sets showed differential expression at the 0.05 threshold (green line): 605 positive and 643 negative FC values of which 454 in the right and 507 in the left upper corners (± 1.75 FC threshold, red lines, blue circles). B: Fold-change distribution of the 1,248 probe sets.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2666765&req=5

Figure 2: Affymetrix outcome. A: Volcano plot. 1,248 probe-sets showed differential expression at the 0.05 threshold (green line): 605 positive and 643 negative FC values of which 454 in the right and 507 in the left upper corners (± 1.75 FC threshold, red lines, blue circles). B: Fold-change distribution of the 1,248 probe sets.
Mentions: L. amazonensis amastigotes subvert MΦ as host cells where they enter a cell-cycling phase lasting several days (Fig. 1A). We compared the transcriptomes of amastigote-free MΦ and amastigote-harbouring MΦ 24 h after the uptake of amastigotes carefully purified from nude mouse lesions. At this time-point amastigotes were multiplying within a huge PV (Fig. 1B) and their population size had almost doubled (Fig. 1A). Among the 45,101 probe-sets of the Mouse430_2 GeneChip, 1,248 (2.77%) were displaying features of differential expression at the 5% significance level (Fig. 2, see Additional file 1). Of these, 1,206 matched Ingenuity Pathway Analysis database version 5.5.1 which represented 898 genes with a known function. About 80% of these genes were incorporated into either Ingenuity's canonical pathway or biological network (i.e. their products interact with other molecules in Ingenuity's knowledge base). The symbols of the modulated genes are specified in the text (fold change [FC] values between brackets), while their full names are given in Additional file 1. Furthermore, comparable FC values were obtained between the Affymetrix technology and the Real Time quantitative Polymerase Chain Reaction (RTQPCR) method (Table 1) [3].

Bottom Line: A total of 1,248 probe-sets showed significant differential expression.Our findings suggest that the amastigote growth relies on early coordinated gene expression of the MPhi lipid and polyamine pathways.Moreover, these MPhi hosting multiplying L. amazonensis amastigotes display a transcriptional profile biased towards parasite-and host tissue-protective processes.

View Article: PubMed Central - HTML - PubMed

Affiliation: Institut Pasteur, Unité d'Immunophysiologie et Parasitisme Intracellulaire, Département de Parasitologie et Mycologie, Paris, France. josorio@pasteur.fr

ABSTRACT

Background: Mammal macrophages (MPhi) display a wide range of functions which contribute to surveying and maintaining tissue integrity. One such function is phagocytosis, a process known to be subverted by parasites like Leishmania (L). Indeed, the intracellular development of L. amazonensis amastigote relies on the biogenesis and dynamic remodelling of a phagolysosome, termed the parasitophorous vacuole, primarily within dermal MPhi.

Results: Using BALB/c mouse bone marrow-derived MPhi loaded or not with amastigotes, we analyzed the transcriptional signatures of MPhi 24 h later, when the amastigote population was growing. Total RNA from MPhi cultures were processed and hybridized onto Affymetrix Mouse430_2 GeneChips, and some transcripts were also analyzed by Real-Time quantitative PCR (RTQPCR). A total of 1,248 probe-sets showed significant differential expression. Comparable fold-change values were obtained between the Affymetrix technology and the RTQPCR method. Ingenuity Pathway Analysis software pinpointed the up-regulation of the sterol biosynthesis pathway (p-value = 1.31e-02) involving several genes (1.95 to 4.30 fold change values), and the modulation of various genes involved in polyamine synthesis and in pro/counter-inflammatory signalling.

Conclusion: Our findings suggest that the amastigote growth relies on early coordinated gene expression of the MPhi lipid and polyamine pathways. Moreover, these MPhi hosting multiplying L. amazonensis amastigotes display a transcriptional profile biased towards parasite-and host tissue-protective processes.

Show MeSH
Related in: MedlinePlus