Sporothrix schenckii: Difference between revisions
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==Overview== | ==Overview== | ||
'''''Sporothrix schenckii''''' is a [[fungus]] that can be found throughout the world. Areas characterized by warm, humid climates, are ideal for the fungus to thrive. The [[species]] is present in soil as well as in and on living and decomposing plant material such as [[sphagnum|peat moss]]. It can infect humans as well as animals and is the causative agent of [[sporotrichosis]], commonly known as "rose handler's disease".<ref name = "Vasquez">{{cite journal |author=Vásquez-del-Mercado E, Arenas R, Padilla-Desgarenes C |title=Sporotrichosis |journal=Clin. Dermatol. |volume=30 |issue=4 |pages=437–43 |date=July 2012 |pmid=22682194 |doi=10.1016/j.clindermatol.2011.09.017}}</ref> Posttraumatic inoculation of S. schenckii is the typical method of infection. However, sporotrichosis may also develop as a result of spore inhalation, although this mode of transmission is infrequent. Infection commonly occurs in otherwise [[immunocompetence|healthy]] individuals but is rarely life-threatening and can be treated with [[#Treatment|antifungals]]. In the environment, ''Sporothrix schenckii'' exists as a filamentous [[hypha]]e. In host tissue, ''S. schenckii'' thrives as a [[yeast]]. The transition from its hyphal form to yeast form is temperature dependent, making ''S. schenckii'' a [[thermally dimorphic fungus]].<ref name = "Barros">{{cite journal |author=Barros MB, de Almeida Paes R, Schubach AO |title=''Sporothrix schenckii'' and Sporotrichosis |journal=Clin. Microbiol. Rev. |volume=24 |issue=4 |pages=633–54 |date=October 2011 |pmc=3194828 |doi=10.1128/cmr.00007-11 |pmid=21976602}}</ref> | '''''Sporothrix schenckii''''' is a [[fungus]] that can be found throughout the world. Areas characterized by warm, humid climates, are ideal for the fungus to thrive. The [[species]] is present in soil as well as in and on living and decomposing plant material such as [[sphagnum|peat moss]]. It can infect humans as well as animals and is the causative agent of [[sporotrichosis]], commonly known as "rose handler's disease".<ref name="Vasquez">{{cite journal |author=Vásquez-del-Mercado E, Arenas R, Padilla-Desgarenes C |title=Sporotrichosis |journal=Clin. Dermatol. |volume=30 |issue=4 |pages=437–43 |date=July 2012 |pmid=22682194 |doi=10.1016/j.clindermatol.2011.09.017}}</ref> Posttraumatic inoculation of S. schenckii is the typical method of infection. However, sporotrichosis may also develop as a result of spore inhalation, although this mode of transmission is infrequent. Infection commonly occurs in otherwise [[immunocompetence|healthy]] individuals but is rarely life-threatening and can be treated with [[#Treatment|antifungals]]. In the environment, ''Sporothrix schenckii'' exists as a filamentous [[hypha]]e. In host tissue, ''S. schenckii'' thrives as a [[yeast]]. The transition from its hyphal form to yeast form is temperature dependent, making ''S. schenckii'' a [[thermally dimorphic fungus]].<ref name="Barros">{{cite journal |author=Barros MB, de Almeida Paes R, Schubach AO |title=''Sporothrix schenckii'' and Sporotrichosis |journal=Clin. Microbiol. Rev. |volume=24 |issue=4 |pages=633–54 |date=October 2011 |pmc=3194828 |doi=10.1128/cmr.00007-11 |pmid=21976602}}</ref> | ||
==Morphology== | ==Morphology== | ||
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===Hyphal=== | ===Hyphal=== | ||
When in the environment or grown in the laboratory at {{convert|25|C|F}} ''S. schenckii'' assumes its hyphal form.<ref name = Morris-Jones /> Macroscopically, filaments are apparent and colonies are moist, leathery to velvety, and have a finely wrinkled surface. The colour is white initially and may change color over time to become cream to dark brown (“dirty candle-wax” color).<ref name = Barros /> Microscopically, hyphae are [[hypha#Structure|septate]] approximately 1 to 2μm in diameter. [[Conidia]] are oval shaped and glass like ([[hyaline]]) in appearance. They may be colorless or darkly colored. Conidia are sometimes referred to as resembling a flower.<ref name = "MycologyOnline">[http://www.mycology.adelaide.edu.au/Fungal_Descriptions/Hyphomycetes_%28dematiaceous%29/Sporothrix/] Mycology Online - University of Adelaide</ref> | When in the environment or grown in the laboratory at {{convert|25|C|F}} ''S. schenckii'' assumes its hyphal form.<ref name="Morris-Jones" /> Macroscopically, filaments are apparent and colonies are moist, leathery to velvety, and have a finely wrinkled surface. The colour is white initially and may change color over time to become cream to dark brown (“dirty candle-wax” color).<ref name="Barros" /> Microscopically, hyphae are [[hypha#Structure|septate]] approximately 1 to 2μm in diameter. [[Conidia]] are oval shaped and glass like ([[hyaline]]) in appearance. They may be colorless or darkly colored. Conidia are sometimes referred to as resembling a flower.<ref name="MycologyOnline">[http://www.mycology.adelaide.edu.au/Fungal_Descriptions/Hyphomycetes_%28dematiaceous%29/Sporothrix/] Mycology Online - University of Adelaide</ref> | ||
===Yeast=== | ===Yeast=== | ||
At {{convert|37|C|F}} either in the laboratory or in host tissue, ''S. schenckii'' assumes its yeast form. [[Macroscopic scale|Macroscopically]], the yeast form grows as smooth white or off-white colonies. Microscopically, yeast cells are 2 to 6μm long and show an elongated cigar-shaped morphology.<ref name = | At {{convert|37|C|F}} either in the laboratory or in host tissue, ''S. schenckii'' assumes its yeast form. [[Macroscopic scale|Macroscopically]], the yeast form grows as smooth white or off-white colonies. Microscopically, yeast cells are 2 to 6μm long and show an elongated cigar-shaped morphology.<ref name="Barros" /> | ||
==Virulence Factors== | ==Virulence Factors== | ||
===Melanin Production=== | ===Melanin Production=== | ||
''S. schenckii'' synthesizes [[melanin]] both ''in vitro'' and ''[[in vivo]]''<ref name = "Morris-Jones">{{cite journal |author=Morris-Jones R, Youngchim S, Gomez BL, ''et al.'' |title=Synthesis of melanin-like pigments by ''Sporothrix schenckii'' in vitro and during mammalian infection |journal=Infect. Immun. |volume=71 |issue=7 |pages=4026–33 |date=July 2003 |pmc=161969 |doi=10.1128/iai.71.7.4026-4033.2003 |pmid=12819091}}</ref> | ''S. schenckii'' synthesizes [[melanin]] both ''in vitro'' and ''[[in vivo]]''<ref name="Morris-Jones">{{cite journal |author=Morris-Jones R, Youngchim S, Gomez BL, ''et al.'' |title=Synthesis of melanin-like pigments by ''Sporothrix schenckii'' in vitro and during mammalian infection |journal=Infect. Immun. |volume=71 |issue=7 |pages=4026–33 |date=July 2003 |pmc=161969 |doi=10.1128/iai.71.7.4026-4033.2003 |pmid=12819091}}</ref> | ||
Melanin production is a virulence factor found in many fungi that cause disease<ref name = "Revankar">{{cite journal |author=Revankar SG, Sutton DA |title=Melanized fungi in human disease |journal=Clin. Microbiol. Rev. |volume=23 |issue=4 |pages=884–928 |date=October 2010 |pmc=2952981 |doi=10.1128/cmr.00019-10 |pmid=20930077}}</ref> and its production in ''S. schenckii'' protects the fungus from oxidative stress as well as [[ultraviolet]] light and [[macrophage]] killing. Melanin has been shown to be synthesized using the 1,8-DHN pentaketide pathway (below).<ref name = Morris-Jones /> | Melanin production is a virulence factor found in many fungi that cause disease<ref name="Revankar">{{cite journal |author=Revankar SG, Sutton DA |title=Melanized fungi in human disease |journal=Clin. Microbiol. Rev. |volume=23 |issue=4 |pages=884–928 |date=October 2010 |pmc=2952981 |doi=10.1128/cmr.00019-10 |pmid=20930077}}</ref> and its production in ''S. schenckii'' protects the fungus from oxidative stress as well as [[ultraviolet]] light and [[macrophage]] killing. Melanin has been shown to be synthesized using the 1,8-DHN pentaketide pathway (below).<ref name="Morris-Jones" /> | ||
===Adhesins=== | ===Adhesins=== | ||
Adhesion is an important component of pathogenesis. The yeast form of ''S. schenckii'' shows an increased ability to bind<ref name = "Barros" /> to the host extracellular matrix proteins [[fibronectin]] and [[laminin]] using two separate receptors specific for these proteins.<ref name = "Lima">{{cite journal |author=Lima OC, Bouchara JP, Renier G, Marot-Leblond A, Chabasse D, Lopes-Bezerra LM |title=Immunofluorescence and flow cytometry analysis of fibronectin and laminin binding to ''Sporothrix schenckii'' yeast cells and conidia |journal=Microb. Pathog. |volume=37 |issue=3 |pages=131–40 |date=September 2004 |pmid=15351036 |doi=10.1016/j.micpath.2004.06.005}}</ref> | Adhesion is an important component of pathogenesis. The yeast form of ''S. schenckii'' shows an increased ability to bind<ref name="Barros" /> to the host extracellular matrix proteins [[fibronectin]] and [[laminin]] using two separate receptors specific for these proteins.<ref name="Lima">{{cite journal |author=Lima OC, Bouchara JP, Renier G, Marot-Leblond A, Chabasse D, Lopes-Bezerra LM |title=Immunofluorescence and flow cytometry analysis of fibronectin and laminin binding to ''Sporothrix schenckii'' yeast cells and conidia |journal=Microb. Pathog. |volume=37 |issue=3 |pages=131–40 |date=September 2004 |pmid=15351036 |doi=10.1016/j.micpath.2004.06.005}}</ref> | ||
===Proteases=== | ===Proteases=== | ||
''S. schenckii'' breaks down proteins by producing two separate [[protease]]s, a [[serine protease]] and an [[aspartate protease|aspartic protease]].<ref name = "Hogan">{{cite journal |author=Hogan LH, Klein BS, Levitz SM |title=Virulence factors of medically important fungi |journal=Clin. Microbiol. Rev. |volume=9 |issue=4 |pages=469–88 |date=October 1996 |pmc=172905 |pmid=8894347}}</ref> These proteases appear to be essential for fungal growth. However, they have some functional overlap as the inactivation of either protein does not affect growth but inactivation of both inhibits the fungus.<ref name = "Tsuboi">{{cite journal |author=Tsuboi R, Sanada T, Ogawa H |title=Influence of culture medium pH and proteinase inhibitors on extracellular proteinase activity and cell growth of ''Sporothrix schenckii'' |journal=J. Clin. Microbiol. |volume=26 |issue=7 |pages=1431–3 |date=July 1988 |pmc=266631 |pmid=3045155}}</ref> Protease activity has been shown to be important in ''in vivo'' infection of mice.<ref name = "Hogan" /> Substrates for these proteases include the skin proteins [[type-I collagen]], [[stratum corneum]], and [[elastin]].<ref name = "Hogan" /> | ''S. schenckii'' breaks down proteins by producing two separate [[protease]]s, a [[serine protease]] and an [[aspartate protease|aspartic protease]].<ref name="Hogan">{{cite journal |author=Hogan LH, Klein BS, Levitz SM |title=Virulence factors of medically important fungi |journal=Clin. Microbiol. Rev. |volume=9 |issue=4 |pages=469–88 |date=October 1996 |pmc=172905 |pmid=8894347}}</ref> These proteases appear to be essential for fungal growth. However, they have some functional overlap as the inactivation of either protein does not affect growth but inactivation of both inhibits the fungus.<ref name="Tsuboi">{{cite journal |author=Tsuboi R, Sanada T, Ogawa H |title=Influence of culture medium pH and proteinase inhibitors on extracellular proteinase activity and cell growth of ''Sporothrix schenckii'' |journal=J. Clin. Microbiol. |volume=26 |issue=7 |pages=1431–3 |date=July 1988 |pmc=266631 |pmid=3045155}}</ref> Protease activity has been shown to be important in ''in vivo'' infection of mice.<ref name="Hogan" /> Substrates for these proteases include the skin proteins [[type-I collagen]], [[stratum corneum]], and [[elastin]].<ref name="Hogan" /> | ||
===Heat Tolerance=== | ===Heat Tolerance=== | ||
Growing at host body temperature ({{convert|37|C|F}}) is an important requirement for pathogenesis. Some strains of ''S. schenckii'' are restricted to growing at {{convert|35|C|F}} and consequently usually cause disease only on the skin as it is cooler than the body's interior. Those that are capable of growth at body temperature are more often associated with disseminated disease.<ref name = "Hogan" /> | Growing at host body temperature ({{convert|37|C|F}}) is an important requirement for pathogenesis. Some strains of ''S. schenckii'' are restricted to growing at {{convert|35|C|F}} and consequently usually cause disease only on the skin as it is cooler than the body's interior. Those that are capable of growth at body temperature are more often associated with disseminated disease.<ref name="Hogan" /> | ||
==Immune Response== | ==Immune Response== | ||
Infection by ''S. schenckii'' is generally [[self-limiting (biology)|self-limiting]] in immunocompetent hosts. The immune response prevents fungal dissemination and is the reason that most ''Sporothrix'' infections are [[#Cutaneous and Lymphocutaneous|cutaneous]].<ref name = "Carlos">{{cite journal |author=Carlos IZ, Sassá MF, da Graça Sgarbi DB, Placeres MC, Maia DC |title=Current research on the immune response to experimental sporotrichosis |journal=Mycopathologia |volume=168 |issue=1 |pages=1–10 |date=July 2009 |pmid=19241140 |doi=10.1007/s11046-009-9190-z}}</ref> | Infection by ''S. schenckii'' is generally [[self-limiting (biology)|self-limiting]] in immunocompetent hosts. The immune response prevents fungal dissemination and is the reason that most ''Sporothrix'' infections are [[#Cutaneous and Lymphocutaneous|cutaneous]].<ref name="Carlos">{{cite journal |author=Carlos IZ, Sassá MF, da Graça Sgarbi DB, Placeres MC, Maia DC |title=Current research on the immune response to experimental sporotrichosis |journal=Mycopathologia |volume=168 |issue=1 |pages=1–10 |date=July 2009 |pmid=19241140 |doi=10.1007/s11046-009-9190-z}}</ref> | ||
===Innate=== | ===Innate=== | ||
The yeast form of ''S. schenckii'' is effectively [[phagocytosis|phagocytosed]] by [[innate immune system#Cells of the innate immune response|cells of the innate immune system]]<ref name = "Carlos" /> and are recognized based on the sugars displayed on their surface<ref name = "Oda">{{cite journal |author=Oda LM, Kubelka CF, Alviano CS, Travassos LR |title=Ingestion of yeast forms of ''Sporothrix schenckii'' by mouse peritoneal macrophages |journal=Infect. Immun. |volume=39 |issue=2 |pages=497–504 |date=February 1983 |pmc=347978 |pmid=6832808}}</ref> or lipids in the yeast cell mebrane.<ref name = "Carlos" /> Although they are taken up, they are not efficiently killed. It is hypothesized that [[ergosterol peroxide]] reacts with and detoxifies [[reactive oxygen species]] generated by the [[respiratory burst]] used by phagocytes to kill cells they have ingested.<ref name = "Carlos" /> ''S. schenckii'' is also capable of modulating the immune response to promote its own survival by blocking [[cytokine]] production by macrophages.<ref name = "Carlos" /> | The yeast form of ''S. schenckii'' is effectively [[phagocytosis|phagocytosed]] by [[innate immune system#Cells of the innate immune response|cells of the innate immune system]]<ref name="Carlos" /> and are recognized based on the sugars displayed on their surface<ref name="Oda">{{cite journal |author=Oda LM, Kubelka CF, Alviano CS, Travassos LR |title=Ingestion of yeast forms of ''Sporothrix schenckii'' by mouse peritoneal macrophages |journal=Infect. Immun. |volume=39 |issue=2 |pages=497–504 |date=February 1983 |pmc=347978 |pmid=6832808}}</ref> or lipids in the yeast cell mebrane.<ref name="Carlos" /> Although they are taken up, they are not efficiently killed. It is hypothesized that [[ergosterol peroxide]] reacts with and detoxifies [[reactive oxygen species]] generated by the [[respiratory burst]] used by phagocytes to kill cells they have ingested.<ref name="Carlos" /> ''S. schenckii'' is also capable of modulating the immune response to promote its own survival by blocking [[cytokine]] production by macrophages.<ref name="Carlos" /> | ||
===Specific=== | ===Specific=== | ||
The specific immune response is active later in infection and involves both [[B cell]]s and [[T cell]]s. Severe sporotrichosis is rare in endemic areas where humans are in near constant contact with ''S. schenckii'' spores. This fact, combined with the increased severity of disease in immunocompromised patients points to an important role for [[adaptive immune system|specific immunity]] in ''S. schenckii'' infection.<ref name = "Carlos" /> Patients with sporotrichosis have been shown to produce antibodies specific to ''S. schenckii''<ref name = "Scott">{{cite journal |author=Scott EN, Muchmore HG |title=Immunoblot analysis of antibody responses to ''Sporothrix schenckii'' |journal=J. Clin. Microbiol. |volume=27 |issue=2 |pages=300–4 |date=February 1989 |pmc=267296 |pmid=2915023}}</ref> and these antibodies may actually be protective against the disease.<ref name = Barros /> | The specific immune response is active later in infection and involves both [[B cell]]s and [[T cell]]s. Severe sporotrichosis is rare in endemic areas where humans are in near constant contact with ''S. schenckii'' spores. This fact, combined with the increased severity of disease in immunocompromised patients points to an important role for [[adaptive immune system|specific immunity]] in ''S. schenckii'' infection.<ref name="Carlos" /> Patients with sporotrichosis have been shown to produce antibodies specific to ''S. schenckii''<ref name="Scott">{{cite journal |author=Scott EN, Muchmore HG |title=Immunoblot analysis of antibody responses to ''Sporothrix schenckii'' |journal=J. Clin. Microbiol. |volume=27 |issue=2 |pages=300–4 |date=February 1989 |pmc=267296 |pmid=2915023}}</ref> and these antibodies may actually be protective against the disease.<ref name="Barros" /> | ||
==References== | ==References== | ||
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*[http://botit.botany.wisc.edu/toms_fungi/feb2003.html Fungus Page: ''Sporothrix schenckii'', cause of Rose-picker's Disease] | *[http://botit.botany.wisc.edu/toms_fungi/feb2003.html Fungus Page: ''Sporothrix schenckii'', cause of Rose-picker's Disease] | ||
*[http://emedicine.medscape.com/article/228723-overview EMedicine: Sporotrichosis] | *[http://emedicine.medscape.com/article/228723-overview EMedicine: Sporotrichosis] | ||
*[http://www.mycology.adelaide.edu.au/Fungal_Descriptions/Hyphomycetes_%28dematiaceous%29/Sporothrix/ | *[http://www.mycology.adelaide.edu.au/Fungal_Descriptions/Hyphomycetes_%28dematiaceous%29/Sporothrix/ Adelaide University: ''Sporothrix schenckii''] | ||
*[http://cmr.asm.org/content/24/4/633.abstract American Society for Microbiology: ''Sporothrix schenckii'' and Sporotrichosis] | *[http://cmr.asm.org/content/24/4/633.abstract American Society for Microbiology: ''Sporothrix schenckii'' and Sporotrichosis] | ||
*[http://microbewiki.kenyon.edu/index.php/Sporothrix_schenckii Microbe wiki: ''Sporothrix schenckii''] | *[http://microbewiki.kenyon.edu/index.php/Sporothrix_schenckii Microbe wiki: ''Sporothrix schenckii''] |
Revision as of 16:25, 13 January 2016
Sporotrichosis Microchapters |
Diagnosis |
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Treatment |
Case Studies |
Sporothrix schenckii On the Web |
American Roentgen Ray Society Images of Sporothrix schenckii |
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Conidiophores and conidia Conidiophores and conidia
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style="background:#Template:Taxobox colour;" | Scientific classification | ||||||||||||||
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Binomial name | ||||||||||||||
Sporothrix schenckii Hektoen & C.F.Perkins (1900) |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [2] Alison Leibowitz [3]
Overview
Sporothrix schenckii is a fungus that can be found throughout the world. Areas characterized by warm, humid climates, are ideal for the fungus to thrive. The species is present in soil as well as in and on living and decomposing plant material such as peat moss. It can infect humans as well as animals and is the causative agent of sporotrichosis, commonly known as "rose handler's disease".[1] Posttraumatic inoculation of S. schenckii is the typical method of infection. However, sporotrichosis may also develop as a result of spore inhalation, although this mode of transmission is infrequent. Infection commonly occurs in otherwise healthy individuals but is rarely life-threatening and can be treated with antifungals. In the environment, Sporothrix schenckii exists as a filamentous hyphae. In host tissue, S. schenckii thrives as a yeast. The transition from its hyphal form to yeast form is temperature dependent, making S. schenckii a thermally dimorphic fungus.[2]
Morphology
Template:Triple image Sporothrix schenckii can be found in one of two morphologies, hyphal or yeast. The hyphal form is found in the environment on plants and decaying matter. When the fungus makes the transition into a host, the yeast morphology predominates.
Hyphal
When in the environment or grown in the laboratory at 25 °C (77 °F) S. schenckii assumes its hyphal form.[3] Macroscopically, filaments are apparent and colonies are moist, leathery to velvety, and have a finely wrinkled surface. The colour is white initially and may change color over time to become cream to dark brown (“dirty candle-wax” color).[2] Microscopically, hyphae are septate approximately 1 to 2μm in diameter. Conidia are oval shaped and glass like (hyaline) in appearance. They may be colorless or darkly colored. Conidia are sometimes referred to as resembling a flower.[4]
Yeast
At 37 °C (98.6 °F) either in the laboratory or in host tissue, S. schenckii assumes its yeast form. Macroscopically, the yeast form grows as smooth white or off-white colonies. Microscopically, yeast cells are 2 to 6μm long and show an elongated cigar-shaped morphology.[2]
Virulence Factors
Melanin Production
S. schenckii synthesizes melanin both in vitro and in vivo[3] Melanin production is a virulence factor found in many fungi that cause disease[5] and its production in S. schenckii protects the fungus from oxidative stress as well as ultraviolet light and macrophage killing. Melanin has been shown to be synthesized using the 1,8-DHN pentaketide pathway (below).[3]
Adhesins
Adhesion is an important component of pathogenesis. The yeast form of S. schenckii shows an increased ability to bind[2] to the host extracellular matrix proteins fibronectin and laminin using two separate receptors specific for these proteins.[6]
Proteases
S. schenckii breaks down proteins by producing two separate proteases, a serine protease and an aspartic protease.[7] These proteases appear to be essential for fungal growth. However, they have some functional overlap as the inactivation of either protein does not affect growth but inactivation of both inhibits the fungus.[8] Protease activity has been shown to be important in in vivo infection of mice.[7] Substrates for these proteases include the skin proteins type-I collagen, stratum corneum, and elastin.[7]
Heat Tolerance
Growing at host body temperature (37 °C (98.6 °F)) is an important requirement for pathogenesis. Some strains of S. schenckii are restricted to growing at 35 °C (95 °F) and consequently usually cause disease only on the skin as it is cooler than the body's interior. Those that are capable of growth at body temperature are more often associated with disseminated disease.[7]
Immune Response
Infection by S. schenckii is generally self-limiting in immunocompetent hosts. The immune response prevents fungal dissemination and is the reason that most Sporothrix infections are cutaneous.[9]
Innate
The yeast form of S. schenckii is effectively phagocytosed by cells of the innate immune system[9] and are recognized based on the sugars displayed on their surface[10] or lipids in the yeast cell mebrane.[9] Although they are taken up, they are not efficiently killed. It is hypothesized that ergosterol peroxide reacts with and detoxifies reactive oxygen species generated by the respiratory burst used by phagocytes to kill cells they have ingested.[9] S. schenckii is also capable of modulating the immune response to promote its own survival by blocking cytokine production by macrophages.[9]
Specific
The specific immune response is active later in infection and involves both B cells and T cells. Severe sporotrichosis is rare in endemic areas where humans are in near constant contact with S. schenckii spores. This fact, combined with the increased severity of disease in immunocompromised patients points to an important role for specific immunity in S. schenckii infection.[9] Patients with sporotrichosis have been shown to produce antibodies specific to S. schenckii[11] and these antibodies may actually be protective against the disease.[2]
References
- ↑ Vásquez-del-Mercado E, Arenas R, Padilla-Desgarenes C (July 2012). "Sporotrichosis". Clin. Dermatol. 30 (4): 437–43. doi:10.1016/j.clindermatol.2011.09.017. PMID 22682194.
- ↑ 2.0 2.1 2.2 2.3 2.4 Barros MB, de Almeida Paes R, Schubach AO (October 2011). "Sporothrix schenckii and Sporotrichosis". Clin. Microbiol. Rev. 24 (4): 633–54. doi:10.1128/cmr.00007-11. PMC 3194828. PMID 21976602.
- ↑ 3.0 3.1 3.2 Morris-Jones R, Youngchim S, Gomez BL; et al. (July 2003). "Synthesis of melanin-like pigments by Sporothrix schenckii in vitro and during mammalian infection". Infect. Immun. 71 (7): 4026–33. doi:10.1128/iai.71.7.4026-4033.2003. PMC 161969. PMID 12819091.
- ↑ [1] Mycology Online - University of Adelaide
- ↑ Revankar SG, Sutton DA (October 2010). "Melanized fungi in human disease". Clin. Microbiol. Rev. 23 (4): 884–928. doi:10.1128/cmr.00019-10. PMC 2952981. PMID 20930077.
- ↑ Lima OC, Bouchara JP, Renier G, Marot-Leblond A, Chabasse D, Lopes-Bezerra LM (September 2004). "Immunofluorescence and flow cytometry analysis of fibronectin and laminin binding to Sporothrix schenckii yeast cells and conidia". Microb. Pathog. 37 (3): 131–40. doi:10.1016/j.micpath.2004.06.005. PMID 15351036.
- ↑ 7.0 7.1 7.2 7.3 Hogan LH, Klein BS, Levitz SM (October 1996). "Virulence factors of medically important fungi". Clin. Microbiol. Rev. 9 (4): 469–88. PMC 172905. PMID 8894347.
- ↑ Tsuboi R, Sanada T, Ogawa H (July 1988). "Influence of culture medium pH and proteinase inhibitors on extracellular proteinase activity and cell growth of Sporothrix schenckii". J. Clin. Microbiol. 26 (7): 1431–3. PMC 266631. PMID 3045155.
- ↑ 9.0 9.1 9.2 9.3 9.4 9.5 Carlos IZ, Sassá MF, da Graça Sgarbi DB, Placeres MC, Maia DC (July 2009). "Current research on the immune response to experimental sporotrichosis". Mycopathologia. 168 (1): 1–10. doi:10.1007/s11046-009-9190-z. PMID 19241140.
- ↑ Oda LM, Kubelka CF, Alviano CS, Travassos LR (February 1983). "Ingestion of yeast forms of Sporothrix schenckii by mouse peritoneal macrophages". Infect. Immun. 39 (2): 497–504. PMC 347978. PMID 6832808.
- ↑ Scott EN, Muchmore HG (February 1989). "Immunoblot analysis of antibody responses to Sporothrix schenckii". J. Clin. Microbiol. 27 (2): 300–4. PMC 267296. PMID 2915023.