D. Herbert Opi

Research interests

Infection with the malaria parasite is associated with significant morbidity and mortality that has resulted in the selection of important host genetic factors that are thought to confer a survival advantage against the debilitating effects of severe clinical malaria. Of interest most of these protective factors are associated with the red blood cell, an important stage during the life cycle of the malaria parasite.  The best studied of these include the haemoglobin disorders of sickle cell trait and α+thalassaemia. Recent evidence however shows that co-inheritance of these conditions, common in malaria endemic areas, is associated with loss of the individual malaria protection associated with each condition individually. My work involves investigating biological mechanisms that may explain this negative interaction specifically looking at the effect of co-inheritance on the important parasite virulence phenotypes of cytoadherence, rosetting, and erythrocyte PfEMP1 and knob expression. I am also investigating the role of other red cell associated host genetic factors including the ABO blood group antigens and the complement receptor 1 expressed on the surface of red cells on malaria pathogenesis. Using different cohorts from malaria endemic coastal Kenya and Mali in West Africa I am carrying out both case-control and prospective longitudinal studies examining their association with malaria and additionally other non-malaria related illnesses commonly occurring in these populations. This work also extends in to investigating in-vitro correlates for the associations seen with these polymorphisms and malaria in the field studies.

Thesis title: Polymorphisms of the Red Blood Cell surface and their association with malaria

CV

2002 – 2006

  • BSc in Biochemistry and Zoology, University of Nairobi, Kenya

2007

  • Research Intern Kemri-Wellcome Trust Research Programme, Kilifi, Kenya

2007 – 2008

  • MRes Advanced Genetic Analysis, University of Leeds, UK

2009 – Present

  • PhD Student, KEMRI-Wellcome Trust Research Programme/University of Edinburgh, UK

Publications

Opi, DH, Ugoya, S, Williams, TN, Rowe, JA. 2016.

Red blood cell Complement Receptor One level varies with Knops blood group, alpha+thalassaemia and age among Kenyan children.
Genes and Immunity doi: 10.1038/gene.2016.2. PDF

Opi DH, Ochola LB, Tendwa M, Siddondo BR, Ocholla H, Fanjo H, Ghumra A, Ferguson DJP, Williams TN*, Rowe JA* (joint senior authors). 2014.

Mechanistic Studies of the Negative Epistatic Malaria-protective Interaction Between Sickle Cell Trait and α+thalassemia
EBioMedicine 1;1:29-36 doi:10.1016/j.ebiom.2014.10.006 PDF

McAuley CF, Webb C, Makani J, Macharia A, Uyoga S, Opi DH, Ndila C, Ngatia A, Scott JA, Marsh K, Williams TN. 2010.

High mortality from Plasmodium falciparum malaria in children living with sickle cell anemia on the coast of Kenya
Blood 116:1663-1668

Rowe JA, Opi DH, Williams TN. 2009.

Blood groups and malaria: insights into pathogenesis and identification of targets for intervention.  
Current Opinion in Hematology 16:480-487 PDF

Williams TN, Uyoga S, Macharia A, Ndila C, McAuley CF, Opi DH, Mwarumba S, Makani J, Komba A, Ndiritu MN, Sharif SK, Marsh K, Berkley JA, Scott JA. 2009.

Bacteraemia in Kenyan children with sickle-cell anaemia: a retrospective cohort and case-control study
Lancet 374:1364-1370

Idro R, Williams TN, Gwer S, Uyoga S, Macharia A, Opi H, Atkinson S, Maitland K, Kager PA, Kwiatkowski D, Neville BG, Newton CR. 2008.

Haptoglobin HP2-2 genotype, alpha-thalassaemia and acute seizures in children living in a malaria-endemic area
Epilepsy Res 81:114-118