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Sánchez-Arcila JC, Jensen KDC. Forward Genetics in Apicomplexa Biology: The Host Side of the Story. Front Cell Infect Microbiol 2022; 12:878475. [PMID: 35646724 PMCID: PMC9133346 DOI: 10.3389/fcimb.2022.878475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 03/31/2022] [Indexed: 11/13/2022] Open
Abstract
Forward genetic approaches have been widely used in parasitology and have proven their power to reveal the complexities of host-parasite interactions in an unbiased fashion. Many aspects of the parasite’s biology, including the identification of virulence factors, replication determinants, antibiotic resistance genes, and other factors required for parasitic life, have been discovered using such strategies. Forward genetic approaches have also been employed to understand host resistance mechanisms to parasitic infection. Here, we will introduce and review all forward genetic approaches that have been used to identify host factors involved with Apicomplexa infections, which include classical genetic screens and QTL mapping, GWAS, ENU mutagenesis, overexpression, RNAi and CRISPR-Cas9 library screens. Collectively, these screens have improved our understanding of host resistance mechanisms, immune regulation, vaccine and drug designs for Apicomplexa parasites. We will also discuss how recent advances in molecular genetics give present opportunities to further explore host-parasite relationships.
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Affiliation(s)
- Juan C. Sánchez-Arcila
- Department of Molecular and Cell Biology, University of California Merced, Merced, CA, United States
| | - Kirk D. C. Jensen
- Department of Molecular and Cell Biology, University of California Merced, Merced, CA, United States
- Health Science Research Institute, University of California, Merced, Merced, CA, United States
- *Correspondence: Kirk D. C. Jensen,
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Huang HM, McMorran BJ, Foote SJ, Burgio G. Host genetics in malaria: lessons from mouse studies. Mamm Genome 2018; 29:507-522. [PMID: 29594458 DOI: 10.1007/s00335-018-9744-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2017] [Accepted: 03/22/2018] [Indexed: 01/09/2023]
Abstract
Malaria remains a deadly parasitic disease caused by Plasmodium, claiming almost half a million lives every year. While parasite genetics and biology are often the major targets in many studies, it is becoming more evident that host genetics plays a crucial role in the outcome of the infection. Similarly, Plasmodium infections in mice also rely heavily on the genetic background of the mice, and often correlate with observations in human studies, due to their high genetic homology with humans. As such, murine models of malaria are a useful tool for understanding host responses during Plasmodium infections, as well as dissecting host-parasite interactions through various genetic manipulation techniques. Reverse genetic approach such as quantitative trait loci studies and random mutagenesis screens have been employed to discover novel host genes that affect malaria susceptibility in mouse models, while other targeted studies utilize mouse models to validate observation from human studies. Herein, we review the findings from the past and present studies on murine models of hepatic and erythrocytic stages of malaria and speculate on how the current mouse models benefit from the recent development in CRISPR/Cas9 gene editing technology.
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Affiliation(s)
- Hong Ming Huang
- Department of Immunology and Infectious Disease, John Curtin School of Medical Research, Australian National University, 131 Garran Road, Canberra, ACT, 2601, Australia
| | - Brendan J McMorran
- Department of Immunology and Infectious Disease, John Curtin School of Medical Research, Australian National University, 131 Garran Road, Canberra, ACT, 2601, Australia
| | - Simon J Foote
- Department of Immunology and Infectious Disease, John Curtin School of Medical Research, Australian National University, 131 Garran Road, Canberra, ACT, 2601, Australia
| | - Gaetan Burgio
- Department of Immunology and Infectious Disease, John Curtin School of Medical Research, Australian National University, 131 Garran Road, Canberra, ACT, 2601, Australia.
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Laroque A, Min-Oo G, Tam M, Ponka P, Stevenson MM, Gros P. The mouse Char10 locus regulates severity of pyruvate kinase deficiency and susceptibility to malaria. PLoS One 2017; 12:e0177818. [PMID: 28542307 PMCID: PMC5436716 DOI: 10.1371/journal.pone.0177818] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Accepted: 05/03/2017] [Indexed: 11/18/2022] Open
Abstract
Pyruvate kinase (PKLR) deficiency protects mice and humans against blood-stage malaria. Although mouse strain AcB62 carries a malaria-protective PklrI90N genetic mutation, it is phenotypically susceptible to blood stage malaria induced by infection with Plasmodium chabaudi AS, suggesting a genetic modifier of the PklrI90N protective effect. Linkage analysis in a F2 cross between AcB62 (PklrI90N) and another PK deficient strain CBA/Pk (PklrG338D) maps this modifier (designated Char10) to chromosome 9 (LOD = 10.8, 95% Bayesian CI = 50.7–75Mb). To study the mechanistic basis of the Char10 effect, we generated an incipient congenic line (Char10C) that harbors the Char10 chromosome 9 segment from AcB62 fixed on the genetic background of CBA/Pk. The Char10 effect is shown to be highly penetrant as the Char10C line recapitulates the AcB62 phenotype, displaying high parasitemia following P. chabaudi infection, compared to CBA/Pk. Char10C mice also display a reduction in anemia phenotypes associated with the PklrG338D mutation including decreased splenomegaly, decreased circulating reticulocytes, increased density of mature erythrocytes, increased hematocrit, as well as decreased iron overload in kidney and liver and decreased serum iron. Erythroid lineage analyses indicate that the number of total TER119+ cells as well as the numbers of the different CD71+/CD44+ erythroblast sub-populations were all found to be lower in Char10C spleen compared to CBA/Pk. Char10C mice also displayed lower number of CFU-E per spleen compared to CBA/Pk. Taken together, these results indicate that the Char10 locus modulates the severity of pyruvate kinase deficiency by regulating erythroid responses in the presence of PK-deficiency associated haemolytic anemia.
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MESH Headings
- Anemia, Hemolytic, Congenital Nonspherocytic/genetics
- Anemia, Hemolytic, Congenital Nonspherocytic/metabolism
- Anemia, Hemolytic, Congenital Nonspherocytic/physiopathology
- Animals
- Chromosomes, Mammalian/genetics
- Erythrocytes/metabolism
- Erythrocytes/pathology
- Erythropoiesis/genetics
- Genetic Loci/genetics
- Genetic Predisposition to Disease/genetics
- Humans
- Iron/metabolism
- Malaria/genetics
- Mice
- Pyruvate Kinase/deficiency
- Pyruvate Kinase/genetics
- Pyruvate Kinase/metabolism
- Pyruvate Metabolism, Inborn Errors/genetics
- Pyruvate Metabolism, Inborn Errors/metabolism
- Pyruvate Metabolism, Inborn Errors/physiopathology
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Affiliation(s)
- Aurélie Laroque
- Biochemistry Department, McGill University, Montreal, Quebec, Canada
| | - Gundula Min-Oo
- Biochemistry Department, McGill University, Montreal, Quebec, Canada
| | - Mifong Tam
- Department of Microbiology and Immunology, McGill University, Montreal, Quebec, Canada
| | - Prem Ponka
- Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, Quebec, Canada
- Physiology Department, McGill University, Montreal, Quebec, Canada
| | - Mary M. Stevenson
- Department of Microbiology and Immunology, McGill University, Montreal, Quebec, Canada
| | - Philippe Gros
- Biochemistry Department, McGill University, Montreal, Quebec, Canada
- * E-mail:
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Hernandez-Valladares M, Rihet P, Iraqi FA. Host susceptibility to malaria in human and mice: compatible approaches to identify potential resistant genes. Physiol Genomics 2014; 46:1-16. [DOI: 10.1152/physiolgenomics.00044.2013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
There is growing evidence for human genetic factors controlling the outcome of malaria infection, while molecular basis of this genetic control is still poorly understood. Case-control and family-based studies have been carried out to identify genes underlying host susceptibility to malarial infection. Parasitemia and mild malaria have been genetically linked to human chromosomes 5q31-q33 and 6p21.3, and several immune genes located within those regions have been associated with malaria-related phenotypes. Association and linkage studies of resistance to malaria are not easy to carry out in human populations, because of the difficulty in surveying a significant number of families. Murine models have proven to be an excellent genetic tool for studying host response to malaria; their use allowed mapping 14 resistance loci, eight of them controlling parasitic levels and six controlling cerebral malaria. Once quantitative trait loci or genes have been identified, the human ortholog may then be identified. Comparative mapping studies showed that a couple of human and mouse might share similar genetically controlled mechanisms of resistance. In this way, char8, which controls parasitemia, was mapped on chromosome 11; char8 corresponds to human chromosome 5q31-q33 and contains immune genes, such as Il3, Il4, Il5, Il12b, Il13, Irf1, and Csf2. Nevertheless, part of the genetic factors controlling malaria traits might differ in both hosts because of specific host-pathogen interactions. Finally, novel genetic tools including animal models were recently developed and will offer new opportunities for identifying genetic factors underlying host phenotypic response to malaria, which will help in better therapeutic strategies including vaccine and drug development.
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Affiliation(s)
| | - Pascal Rihet
- UMR1090 TAGC, INSERM, Marseille, France
- Aix-Marseille University, Marseille, France; and
| | - Fuad A. Iraqi
- Department of Clinical Microbiology and Immunology, Sackler Faculty of Medicine, Tel Aviv University, Ramat Aviv, Tel Aviv, Israel
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Bopp SER, Rodrigo E, González-Páez GE, Frazer M, Barnes SW, Valim C, Watson J, Walker JR, Schmedt C, Winzeler EA. Identification of the Plasmodium berghei resistance locus 9 linked to survival on chromosome 9. Malar J 2013; 12:316. [PMID: 24025732 PMCID: PMC3848760 DOI: 10.1186/1475-2875-12-316] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Accepted: 08/25/2013] [Indexed: 11/10/2022] Open
Abstract
Background One of the main causes of mortality from severe malaria in Plasmodium falciparum infections is cerebral malaria (CM). An important host genetic component determines the susceptibility of an individual to develop CM or to clear the infection and become semi-immune. As such, the identification of genetic loci associated with susceptibility or resistance may serve to modulate disease severity. Methodology The Plasmodium berghei mouse model for experimental cerebral malaria (ECM) reproduces several disease symptoms seen in human CM, and two different phenotypes, a susceptible (FVB/NJ) and a resistant mouse strain (DBA/2J), were examined. Results FVB/NJ mice died from infection within ten days, whereas DBA/2J mice showed a gender bias: males survived on average nineteen days and females either died early with signs of ECM or survived for up to three weeks. A comparison of brain pathology between FVB/NJ and DBA/2J showed no major differences with regard to brain haemorrhages or the number of parasites and CD3+ cells in the microvasculature. However, significant differences were found in the peripheral blood of infected mice: For example resistant DBA/2J mice had significantly higher numbers of circulating basophils than did FVB/NJ mice on day seven. Analysis of the F2 offspring from a cross of DBA/2J and FVB/NJ mice mapped the genetic locus of the underlying survival trait to chromosome 9 with a Lod score of 4.9. This locus overlaps with two previously identified resistance loci (char1 and pymr) from a blood stage malaria model. Conclusions Survival best distinguishes malaria infections between FVB/NJ and DBA/2J mice. The importance of char1 and pymr on chromosome 9 in malaria resistance to P. berghei was confirmed. In addition there was an association of basophil numbers with survival.
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Affiliation(s)
- Selina E R Bopp
- Department of Pediatrics, University of California, San Diego, School of Medicine, La Jolla, CA, USA.
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Wang Y, Chen X, Tsai S, Thomas A, Shizuru JA, Cao TM. Fine mapping of the Bmgr5 quantitative trait locus for allogeneic bone marrow engraftment in mice. Immunogenetics 2013; 65:585-96. [PMID: 23666360 PMCID: PMC3713196 DOI: 10.1007/s00251-013-0709-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Accepted: 04/26/2013] [Indexed: 01/04/2023]
Abstract
To identify novel mechanisms regulating allogeneic hematopoietic cell engraftment, we used forward genetics and previously described identification, in mice, of a bone marrow (BM) engraftment quantitative trait locus (QTL), termed Bmgr5. This QTL confers dominant and large allele effects for engraftment susceptibility. It was localized to chromosome 16 by quantitative genetic techniques in a segregating backcross bred from susceptible BALB.K and resistant B10.BR mice. We now report verification of the Bmgr5 QTL using reciprocal chromosome 16 consomic strains. The BM engraftment phenotype in these consomic mice shows that Bmgr5 susceptibility alleles are not only sufficient but also indispensable for conferring permissiveness for allogeneic BM engraftment. Using panels of congenic mice, we resolved the Bmgr5 QTL into two separate subloci, termed Bmgr5a (Chr16:14.6-15.8 Mb) and Bmgr5b (Chr16:15.8-17.6 Mb), each conferring permissiveness for the engraftment phenotype and both fine mapped to an interval amenable to positional cloning. Candidate Bmgr5 genes were then prioritized using whole exome DNA sequencing and microarray gene expression data. Further studies are warranted to elucidate the genetic interaction between the Bmgr5a and Bmgr5b QTL and identify causative genes and underlying gene variants. This may lead to new approaches for overcoming the problem of graft rejection in clinical hematopoietic cell transplantation.
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Affiliation(s)
- Yuanyuan Wang
- Blood and Marrow Transplantation Program, Department of Medicine, University of Utah, Salt Lake City, UT
| | - Xinjian Chen
- Department of Pathology, University of Utah, Salt Lake City, UT
| | - Schickwann Tsai
- Blood and Marrow Transplantation Program, Department of Medicine, University of Utah, Salt Lake City, UT
| | - Alun Thomas
- Department of Biomedical Informatics, University of Utah, Salt Lake City, UT
- Huntsman Cancer Institute, University of Utah, Salt Lake City, UT
| | - Judith A. Shizuru
- Division of Blood and Marrow Transplantation, Department of Medicine, Stanford University School of Medicine, Stanford, CA
| | - Thai M. Cao
- Blood and Marrow Transplantation Program, Department of Medicine, University of Utah, Salt Lake City, UT
- Huntsman Cancer Institute, University of Utah, Salt Lake City, UT
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Greth A, Lampkin S, Mayura-Guru P, Rodda F, Drysdale K, Roberts-Thomson M, McMorran BJ, Foote SJ, Burgio G. A novel ENU-mutation in ankyrin-1 disrupts malaria parasite maturation in red blood cells of mice. PLoS One 2012; 7:e38999. [PMID: 22723917 PMCID: PMC3378575 DOI: 10.1371/journal.pone.0038999] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Accepted: 05/15/2012] [Indexed: 11/19/2022] Open
Abstract
The blood stage of the plasmodium parasite life cycle is responsible for the clinical symptoms of malaria. Epidemiological studies have identified coincidental malarial endemicity and multiple red blood cell (RBC) disorders. Many RBC disorders result from mutations in genes encoding cytoskeletal proteins and these are associated with increased protection against malarial infections. However the mechanisms underpinning these genetic, host responses remain obscure. We have performed an N-ethyl-N-nitrosourea (ENU) mutagenesis screen and have identified a novel dominant (haploinsufficient) mutation in the Ank-1 gene (Ank1MRI23420) of mice displaying hereditary spherocytosis (HS). Female mice, heterozygous for the Ank-1 mutation showed increased survival to infection by Plasmodium chabaudi adami DS with a concomitant 30% decrease in parasitemia compared to wild-type, isogenic mice (wt). A comparative in vivo red cell invasion and parasite growth assay showed a RBC-autonomous effect characterised by decreased proportion of infected heterozygous RBCs. Within approximately 6–8 hours post-invasion, TUNEL staining of intraerythrocytic parasites, showed a significant increase in dead parasites in heterozygotes. This was especially notable at the ring and trophozoite stages in the blood of infected heterozygous mutant mice compared to wt (p<0.05). We conclude that increased malaria resistance due to ankyrin-1 deficiency is caused by the intraerythrocytic death of P. chabaudi parasites.
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Affiliation(s)
- Andreas Greth
- The Menzies Research Institute of Tasmania, University of Tasmania, Hobart, Australia
- Australian School of Advanced Medicine, Macquarie University, Sydney, Australia
| | - Shelley Lampkin
- The Menzies Research Institute of Tasmania, University of Tasmania, Hobart, Australia
- Australian School of Advanced Medicine, Macquarie University, Sydney, Australia
| | - Preethi Mayura-Guru
- The Menzies Research Institute of Tasmania, University of Tasmania, Hobart, Australia
| | - Fleur Rodda
- The Menzies Research Institute of Tasmania, University of Tasmania, Hobart, Australia
| | - Karen Drysdale
- The Menzies Research Institute of Tasmania, University of Tasmania, Hobart, Australia
| | | | - Brendan J. McMorran
- The Menzies Research Institute of Tasmania, University of Tasmania, Hobart, Australia
- Australian School of Advanced Medicine, Macquarie University, Sydney, Australia
| | - Simon J. Foote
- The Menzies Research Institute of Tasmania, University of Tasmania, Hobart, Australia
- Australian School of Advanced Medicine, Macquarie University, Sydney, Australia
| | - Gaétan Burgio
- The Menzies Research Institute of Tasmania, University of Tasmania, Hobart, Australia
- Australian School of Advanced Medicine, Macquarie University, Sydney, Australia
- * E-mail:
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Laroque A, Min-Oo G, Tam M, Radovanovic I, Stevenson MM, Gros P. Genetic control of susceptibility to infection with Plasmodium chabaudi chabaudi AS in inbred mouse strains. Genes Immun 2011; 13:155-63. [PMID: 21975430 PMCID: PMC4912355 DOI: 10.1038/gene.2011.67] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
To identify genetic effects modulating blood stage replication of the malarial parasite, we phenotyped a group of 25 inbred mouse strains for susceptibility to Plasmodium chabaudi chabaudi AS infection (peak parasitemia, survival). A broad spectrum of responses was observed, with strains such as C57BL/6J being the most resistant (low parasitemia, 100% survival), and strains such as NZW/LacJ and C3HeB/FeJ being extremely susceptible (very high parasitemia and uniform lethality). A number of strains showed intermediate phenotypes and gender specific effects, suggestive of rich genetic diversity in response to malaria in inbred strains. An F2 progeny were generated from SM/J (susceptible) and C57BL/6J (resistant) parental strains, and was phenotyped for susceptibility to P. chabaudi chabaudi AS. A whole genome scan in these animals identified the Char1 locus (LOD=7.40) on chromosome 9 as a key regulator of parasite density and pointed to a conserved 0.4Mb haplotype at Char1 that segregates with susceptibility/resistance to infection. In addition, a second locus was detected in [SM/J x C57BL/6J] F2 mice on the X chromosome (LOD=4.26), which was given the temporary designation Char11. These studies identify a conserved role of Char1 in regulating response to malaria in inbred mouse strains, and provide a prioritized 0.4Mb interval for the search of positional candidates.
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Affiliation(s)
- A Laroque
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada
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Longley R, Smith C, Fortin A, Berghout J, McMorran B, Burgio G, Foote S, Gros P. Host resistance to malaria: using mouse models to explore the host response. Mamm Genome 2010; 22:32-42. [DOI: 10.1007/s00335-010-9302-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2010] [Accepted: 11/03/2010] [Indexed: 11/24/2022]
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Cao TM, Lazzeroni LC, Tsai S, Pang WW, Kao A, Camp NJ, Thomas A, Shizuru JA. Identification of a major susceptibility locus for lethal graft-versus-host disease in MHC-matched mice. THE JOURNAL OF IMMUNOLOGY 2009; 183:462-9. [PMID: 19525392 DOI: 10.4049/jimmunol.0900454] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Graft-vs-host disease (GVHD) is the major cause of morbidity and mortality after allogeneic hemopoietic cell transplantation. From a genetic perspective, GVHD is a complex phenotypic trait. Although it is understood that susceptibility results from interacting polymorphisms of genes encoding histocompatibility Ags and immune regulatory molecules, a detailed and integrative understanding of the genetic background underlying GVHD remains lacking. To gain insight regarding these issues, we performed a forward genetic study. A MHC-matched mouse model was used in which irradiated recipient BALB.K and B10.BR mice demonstrate differential susceptibility to lethal GHVD when transplanted using AKR/J donors. Assessment of GVHD in (B10.BR x BALB.K)F(1) mice revealed that susceptibility is a dominant trait and conferred by deleterious alleles from the BALB.K strain. To identify the alleles responsible for GVHD susceptibility, a genome-scanning approach was taken using (B10.BR x BALB.K)F(1) x B10.BR backcross mice as recipients. A major susceptibility locus, termed the Gvh1 locus, was identified on chromosome 16 using linkage analysis (logarithm of the odds, 9.1). A second locus was found on chromosome 13, named Gvh2, which had additive but protective effects. Further identification of Gvh genes by positional cloning may yield new insight into genetic control mechanisms regulating GVHD and potentially reveal novel approaches for effective GVHD therapy.
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Affiliation(s)
- Thai M Cao
- Department of Medicine, University of Utah School of Medicine, Salt Lake City, 84132, USA.
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Gonçalves LA, Almeida P, Mota MM, Penha-Gonçalves C. Malaria liver stage susceptibility locus identified on mouse chromosome 17 by congenic mapping. PLoS One 2008; 3:e1874. [PMID: 18365019 PMCID: PMC2267218 DOI: 10.1371/journal.pone.0001874] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2007] [Accepted: 02/18/2008] [Indexed: 01/27/2023] Open
Abstract
Host genetic variants are known to confer resistance to Plasmodium blood stage infection and to control malaria severity both in humans and mice. This work describes the genetic mapping of a locus for resistance to liver stage parasite in the mouse. First, we show that decreased susceptibility to the liver stage of Plasmodium berghei in the BALB/c mouse strain is attributable to intra-hepatic factors and impacts on the initial phase of blood stage infection. We used QTL mapping techniques to identify a locus controlling this susceptibility phenotype (LOD score 4.2) on mouse chromosome 17 (belr1 locus). Furthermore, analysis of congenic mouse strains delimited the belr1 locus boundaries distally to the H2 region. Quantification of parasites in the liver of infected congenic mice strongly suggested that the belr1 locus represents a genetic factor controlling the expansion of P. berghei in the hepatic tissue. The mapping of belr1 locus raises the hypothesis that host gene variation is able to control the progression of Plasmodium liver stage infection and opens the possibility that the human genomic region orthologue to belr1 may contain genes that confer resistance to the human malaria liver stage.
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Affiliation(s)
| | | | - Maria Manuel Mota
- Instituto Gulbenkian de Ciência, Oeiras, Portugal
- Unidade de Malária, Instituto de Medicina Molecular, Universidade de Lisboa, Lisboa, Portugal
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