Experimental Models of Dermatophytosis

peer reviewedDermatophytosis is a superficial fungal infection of the keratinized structures of the host. Since the last decade, this mycosis became an important health concern due to an increasing prevalence and to the limited number and efficacy of available treatments. Several experimental models have then been developed in order to improve knowledge about this infection and to design new therapeutic strategies. This chapter presents the variety of dermatophytosis experimental models and their contribution in the understanding of mechanisms used by dermatophytes to adhere and to invade the host tissue. Their support to study the establishment of effective antifungal defenses by the host is also summarized. The usefulness of these models for testing the efficacy of antifungal compounds is finally discussed

High Performance of Histidine-Rich Protein 2 Based Rapid Diagnostic Tests in French Guiana are Explained by the Absence of pfhrp2 Gene Deletion in P. falciparum

BACKGROUND: Care for malaria patients in endemic areas has been improved through the increasing use of Rapid Diagnostic Tests (RDTs). Most RDTs target the histidine-rich protein-2 antigen (PfHRP2) to detect P. falciparum, as it is abundant and shows great heat stability. However, their use in South America has been widely questioned following a recent publication that pinpoints the high prevalence of Peruvian field isolates lacking the gene encoding this protein. In the remote rural health centers of French Guiana, RDTs are the main diagnosis tools. Therefore, a study of PfHRP2 RDT performances and pfhrp2 genotyping was conducted to determine whether a replacement of the current pLDH-based kit could be considered. METHODS: The performance study compared the SD Malaria Ag test P.f/Pan® kit with the current gold standard diagnosis by microscopy. The prevalence of pfhrp2 and pfhrp3 deletions were evaluated from 221 P. falciparum isolates collected between 2009 and 2011 in French Guiana. RESULTS: Between January 2010 and August 2011, 960 suspected cases of malaria were analyzed using microscopy and RDTs. The sensitivity of the SD Malaria Ag test P.f/Pan® for detection of P. falciparum was 96.8% (95% CI: 90.9-99.3), and 86.0% (95% CI: 78.9-91.5) for the detection of P. vivax. No isolates (95% CI: 0-4.5) lacking either exon of the pfhrp2 gene were identified among the 221 P. falciparum isolates analyzed, but 7.4% (95% CI: 2.8-15.4) lacked the exon 2 part of the pfhrp3 gene. CONCLUSIONS: Field isolates lacking either exon of the pfhrp2 gene are absent in this western part of South America. Despite its sensibility to detect P. vivax, the SD Malaria Ag test P.f/Pan® kit is a satisfying alternative to microscopy in remote health centers, where it is difficult to provide highly skilled microscopists and to maintain the necessary equipment

Human epidermal keratinocytes in culture:a story of multiple recipes for a single cell type

Background: For one half-century, cultures of human epidermal keratinocytes have opened new paths of research in skin biology and dermatology. Either performed with serum and feeder-layer, in serum-free conditions, or in autocrine conditions, cells cultured as monolayers became research materials for basic science and dermatology, as well as a source for grafting, particularly to treat severely burned patients. More recently tissue reconstruction at air-liquid interface has opened new perspectives for in vitro toxicology, studies of epidermal barrier, and modeling skin diseases. Summary: This review presents a brief retrospective of the emergence of keratinocyte-based culture techniques. It also presents opportunities and eventual problems that researchers might encounter when exploring the skin using such procedures. Key Messages: While methodologies in tissue culture evolve, the multiplicity of procedures concomitantly increases, requiring to make some selective but difficult choice. Keeping tracks of technological evolution in epidermal cell culture should help choosing the adequate methodology for a specific investigation or innovating with new, more dedicated ones.Background: For one half-century, cultures of human epidermal keratinocytes have opened new paths of research in skin biology and dermatology. Either performed with serum and feeder-layer, in serum-free conditions, or in autocrine conditions, cells cultured as monolayers became research materials for basic science and dermatology, as well as a source for grafting, particularly to treat severely burned patients. More recently tissue reconstruction at air-liquid interface has opened new perspectives for in vitro toxicology, studies of epidermal barrier, and modeling skin diseases.Summary: This review presents a brief retrospective of the emergence of keratinocyte-based culture techniques. It also presents opportunities and eventual problems that researchers might encounter when exploring the skin using such procedures. Key Messages: While methodologies in tissue culture evolve, the multiplicity of procedures concomitantly increases, requiring to make some selective but difficult choice. Keeping tracks of technological evolution in epidermal cell culture should help choosing the adequate methodology for a specific investigation or innovating with new, more dedicated ones

Réponse épidermique aux infections fongiques par dermatophytes

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Réponse épidermique aux infections fongiques par dermatophytes

editorial reviewe