Overexpression of hypoxia-inducible factor 1 alpha impacts FoxP3 levels in mycosis fungoides-Cutaneous T-cell lymphoma: Clinical implications
INTERNATIONAL JOURNAL OF CANCER
2014; 134 (9): 2136-2145
Helminth-excreted/secreted products are recognized by multiple receptors on DCs to block the TLR response and bias Th2 polarization in a cRAF dependent pathway
2013; 27 (11): 4547-4560
Mycosis fungoides (MF) is the most common variant of primary cutaneous T-cell lymphoma, and decreased forkhead box P3 (FoxP3) expression has been reported in MF late stages. Hypoxia-inducible factor 1 alpha (HIF-1α) may regulate FoxP3 expression; however, it is unknown whether HIF-1α is expressed in the CD4(+) T cells of MF patients and how it could affect the expression of FoxP3. Therefore, we evaluated the expression of HIF-1α and FoxP3 in CD4(+) T cells obtained from the skin lesions of MF patients. We found increased cell proliferation and an increase in CD4(+) T cells with an aberrant phenotype among early stage MF patients. HIF-1α was overexpressed in these CD4(+) T cells. In addition, we found a decrease in the percentage of FoxP3(+) cells both in the skin of MF patients, when compared with control skin samples, and with disease progression. In addition, a negative correlation was established between HIF-1α and FoxP3 expression. Skin HIF-1α expression in MF patients correlated with the extent of the affected area and increased with the disease progression. Finally, we showed that ex vivo inhibition of HIF-1α degradation increases the percentage of FoxP3(+) T cells in skin lesions. Our results suggest that overexpression of HIF-1α affects the levels of FoxP3 in MF patients, which could have relevant implications in terms of disease outcome.
View details for DOI 10.1002/ijc.28546
View details for Web of Science ID 000331006600010
View details for PubMedID 24127318
Pathogenic CCR6+ dendritic cells in the skin lesions of discoid lupus patients: a role for damage-associated molecular patterns
EUROPEAN JOURNAL OF DERMATOLOGY
2013; 23 (2): 169-182
Dendritic cells (DCs) recognize pathogens and initiate the T-cell response. The DC-helminth interaction induces an immature phenotype in DCs; as a result, these DCs display impaired responses to TLR stimulation and prime Th2-type responses. However, the DC receptors and intracellular pathways targeted by helminth molecules and their importance in the initiation of the Th2 response are poorly understood. In this report, we found that products excreted/secreted by Taenia crassiceps (TcES) triggered cRAF phosphorylation through MGL, MR, and TLR2. TcES interfered with the LPS-induced NFκB p65 and p38 MAPK signaling pathways. In addition, TcES-induced cRAF signaling pathway was critical for down-regulation of the TLR-mediated DC maturation and secretion of IL-12 and TNF-α. Finally, we show for the first time that blocking cRAF in DCs abolishes their ability to induce Th2 polarization in vitro after TcES exposure. Our data demonstrate a new mechanism by which helminths target intracellular pathways to block DC maturation and efficiently program Th2 polarization.
View details for DOI 10.1096/fj.13-228932
View details for Web of Science ID 000329937500021
View details for PubMedID 23907435
A Toll/IL-1R/resistance domain-containing thioredoxin regulates phagocytosis in Entamoeba histolytica
PARASITES & VECTORS
Discoid lupus erythematosus (DLE) is a cutaneous autoimmune inflammatory disease in which the role of conventional dendritic cells (cDCs) in skin damage has not been evaluated.To evaluate the involvement of cDCs in DLE pathogenesis.Skin biopsies from 42 patients with DLE were embedded in paraffin or placed in culture. The dermis was separated and cell suspensions were characterized by flow cytometry.We found an increase in cDCs with inflammatory characteristics in the skin of DLE patients, compared with control skins. Interestingly, cDCs from the DLE patients expressed low levels of the inhibitory molecule PD-L1 and showed a high expression of CCR6, which correlated with disease activity. Increased cellular death was observed in the skin of DLE patients compared with control skin and remarkably we found that damage-associated molecular patterns could be responsible for CCR6 expression on cDCs in the skin.Our results indicate the presence of pathogenic CCR6+ cDCs in the skin lesions of DLE patients, which could result from in situ phenotypic changes.
View details for DOI 10.1684/ejd.2013.1970
View details for Web of Science ID 000319638600006
View details for PubMedID 23587834
The Role of Lipopeptidophosphoglycan in the Immune Response to Entamoeba histolytica
JOURNAL OF BIOMEDICINE AND BIOTECHNOLOGY
Entamoeba histolytica is a protozoan parasite that infects humans and causes amebiasis affecting developing countries. Phagocytosis of epithelial cells, erythrocytes, leucocytes, and commensal microbiota bacteria is a major pathogenic mechanism used by this parasite. A Toll/IL-1R/Resistance (TIR) domain-containing protein is required in phagocytosis in the social ameba Dictyostelium discoideum, an ameba closely related to Entamoeba histolytica in phylogeny. In insects and vertebrates, TIR domain-containing proteins regulate phagocytic and cell activation. Therefore, we investigated whether E. histolytica expresses TIR domain-containing molecules that may be involved in the phagocytosis of erythrocytes and bacteria.Using in silico analysis we explored in Entamoeba histolytica databases for TIR domain containing sequences. After silencing TIR domain containing sequences in trophozoites by siRNA we evaluated phagocytosis of erythrocytes and bacteria.We identified an E. histolytica thioredoxin containing a TIR-like domain. The secondary and tertiary structure of this sequence exhibited structural similarity to TIR domain family. Thioredoxin transcripts silenced in E. histolytica trophozoites decreased erythrocytes and E. coli phagocytosis.TIR domain-containing thioredoxin of E. histolytica could be an important element in erythrocytes and bacteria phagocytosis.
View details for DOI 10.1186/1756-3305-5-224
View details for Web of Science ID 000310461000002
View details for PubMedID 23043976
The sensing of Pathogen Associated Molecular Patterns (PAMPs) by innate immune receptors, such as Toll-like receptors (TLRs), is the first step in the inflammatory response to pathogens. Entamoeba histolytica, the etiological agent of amebiasis, has a surface molecule with the characteristics of a PAMP. This molecule, which was termed lipopeptidophosphoglycan (LPPG), is recognized through TLR2 and TLR4 and leads to the release of cytokines from human monocytes, macrophages, and dendritic cells; LPPG-activated dendritic cells have increased expression of costimulatory molecules. LPPG activates NKT cells in a CD1d-dependent manner, and this interaction limits amebic liver abscess development. LPPG also induces antibody production, and anti-LPPG antibodies prevent disease development in animal models of amebiasis. Because LPPG is recognized by both the innate and the adaptive immune system (it is a "Pamptigen"), it may be a good candidate to develop a vaccine against E. histolytica infection and an effective adjuvant.
View details for DOI 10.1155/2010/254521
View details for Web of Science ID 000275079500001
View details for PubMedID 20145703