Academic Training

- Licenciado in Biochemistry, Universidad de Concepción, 1982
- Biochemist, Universidad de Concepción, 1984
- Ph.D., Sciences, Universidad Austral de Chile, 1999

Scientific Interests

High density lipoproteins (HDL) are a family of highly heterogenic particles with respect to their composition, structure and function. Although they have been widely studied in mammals and their role in reverse cholesterol transport and their antiatherogenic effect is recognized, little is known about their role in lower vertebrates, particularly in teleost fish. Our laboratory has dedicated over 20 years to structural and functional characterization of HDL in teleost models such as Cyprinus carpio (common carp) and more recently in Oncorhynchus mykiss (rainbow trout). Among the most relevant findings, most worthy of mention is that in both carp and trout, HDL constitutes one of the most abundant protein components of blood plasma (40% and 20% of proteinemia in carp and trout respectively), which suggests that they would fulfil even more relevant and diverse functions than their counterparts in mammals. We have demonstrated that HDL, as well as its major apolipoproteins ApoA-I and ApoA-II, show wide-spectrum antimicrobial activity in vitro. Likewise, we have shown an abundant extrahepatic expression of HDL, particularly in epithelia, mucus membranes and lymphohematopoietic tissues that constitute the primary barriers and essential defensive cells for innate immunity in fish. Considering that fish possess an acquired immunity that is less evolved than mammals and which is highly dependent on their environment, their survival is critically dependent on the efficiency of their innate immune system. For this reason, we are currently interested in evaluating other important defence functions of HDL, such as its role as an immunomodulator and its multiple proteic constituents under normal conditions as well as during the acute phase response. We are also very interested in the proteins and antimicrobial peptides from a more applied or biotechnological point of view, as these molecules are models for the design of new and multifunctional therapeutic agents that might replace conventional antibiotics if they present fewer resistance problems and cytotoxic effects.
 

Relevant Publications

- Otth, C., Zambrano, A., *Concha, M*. (2009) The possible link between herpes simplex virus type 1 infection and neurodegeneration. In: "Current Hypotheses and Research Milestones in Alzheimer´s disease". R.B. Maccioni and G. Perry, eds. SPRINGER -VERLAG, New York- Heidelberg (ISBN 978-0-387-87994-9).


- Villarroel, F., Zambrano, A., Amthauer, R., *Concha, M.I*. (2009) Detection of up-regulated serum amyloid A transcript and of amyloid AA aggregates in skeletal muscle lesions of rainbow trout infected with /Flavobacterium psychrophilum. Vet. Immunol. Immunopathol. /130: 120-124.


- Villarroel, F., Casado, A., Vásquez, J., Araneda, B., Amthauer, R., Matamala, E., Enriquez, R., *Concha, M.I*. (2008) Serum amyloid A: A typical acute-phase reactant in rainbow trout? /Dev. Comp. Immunol/. 32: 1160-1169.


- Villarroel, F., Bastías, A., Casado, A., Amthauer, R. y Concha, M.I. (2007) Apolipoprotein A-I, an antimicrobial protein in Oncorhynchus mykiss: Evaluation of its expresión in primary defence barriers and plasma levels in sick and healthy fish. Fish & Shellfish Immunol. 23:197-209


- Concha, M.I., Smith, V.J., Castro, K., Bastías, A., Romero, A. y Amthauer, R. (2004) Apolipoproteins A-I and A-II are potentially important effectors of innate immunity in the teleost fish Cyprinus carpio. Eur. J. Biochem. 271: 2984-2990.


- Concha, M.I., Molina, S., Oyarzún, C., Villanueva, J. y Amthauer, R. (2003) Local expression of apolipoprotein A-I gene and a possible defensive role for HDL in the carp skin. Fish & Shellfish Immunol. 14: 259-273.


- Concha, M.I. y León, G. (2000) Cloning, functional expression and partial characterization of the glucose kinase from Renibacterium salmoninarum. FEMS Microbiol. Lett. 186 (1): 97-101.


- Amthauer, R., Villanueva, J., Vera , M.I., Concha, M.I., y Krauskopf, M. (1989) Characterization of the major plasma apolipoproteins of the high density lipoprotein in the carp (Cyprinus carpio). Comp. Biochem. Physiol. 92B: 787-793.


- Villarroel, F., Casado,A.,Vásquez, J., Matamala, E., Araneda,B., Amthauer, R., Enriquez, R. y Concha M.I. (2008)  Serum amyloid A: A typical acute-phase reactant in rainbow trout? Developmental & Comparative Immunology 32: 1160-1169.



Photo Gallery

MIC HDL MIC apoA-I carpa MIC HDL MIC apoA-I intestino trucha MIC HDL MIC HDL

Phone: 56-63-221108
Email: margaritaconcha@uach.cl
Campus Isla Teja / Valdivia

- Structure and function of lipoproteins
- Innate immunity
- Antimicrobial peptides and proteins
- Respuesta inflamatoria en un modelo murino

- Dr.Rodolfo Amthauer

Undergraduate Students:
- María José Muñoz
- Jorge Vasquez
- Ella Matamala
- Mauricio Hernández

Research Collaborators
(or Collaborating Institutions)
:
- Dr. Carola Otth (Universidad Austral de Chile)
- Ángara Zambrano (Universidad Austral)

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