Major Areas of Research
- The host immune response to Leishmania transmission by sand fly bites
- Development of Leishmania vaccines and markers of exposure to vector sand flies
- Leishmania-sand fly interactions
- Field-oriented investigations of the epidemiology of leishmaniasis and transmission patterns in cutaneous and visceral leishmaniasis foci
Originally from Jordan, Dr. Kamhawi received her Ph.D. in Medical Entomology at Salford University in England in 1990. She returned to Jordan as an Assistant Professor at Yarmouk University where she worked for several years on hydatid disease and leishmaniasis, with a focus on transmission and risk factors in field settings. After she became an Associate Professor at Yarmouk University, she took a sabbatical in 1997 as a visiting scientist at NIAID’s Laboratory of Parasitic Diseases and become a staff scientist in 2000. In 2006, Dr. Kamhawi moved to NIAID’s Laboratory of Malaria and Vector Research (LMVR) as a core staff scientist and is currently a core associate scientist affiliated with the Vector Molecular Biology Section (VMBS).
The research program is focused on basic and translational aspects of leishmaniasis, a neglected vector-borne (NTD) disease transmitted by phlebotomine sand flies.
The team uses Leishmania-infected sand flies as a natural transmission model for the study of leishmaniasis. Findings from the work emphasized the critical contribution of vectors in the initiation and establishment of vector-borne disease. Recently, the group demonstrated that vector-derived factors such as gut microbiota are egested during bites triggering inflammasome activation in neutrophils and IL-1b production. This leads to acute inflammation found to be key to Leishmania parasite establishment and dissemination. The group also showed that bleeding at the site of bites, that is prolonged due to the anti-hemostatic effects of saliva, triggers the cell stress response and heme oxygenase-1 induction, which dampens inflammation and promotes disease tolerance. These bite-specific immune events shape the early response to Leishmania parasites and are intimately connected to disease outcome. The group continues to investigate the host immune response to vector bites, using it in combination to known risk factors for disease development. Currently, in collaboration with Dr. Peter Melby, University of Texas Medical Department (UTMB) Galveston, the group is investigating the effect of malnutrition on the course of sand fly transmitted visceral leishmaniasis.
Dr. Kamhawi also has a keen interest in field-oriented studies based in leishmaniasis foci. The group has made fundamental discoveries of factors controlling vector competence under laboratory conditions that have yet to be demonstrated in field settings. Currently, Dr. Kamhawi is collaborating with multiple international partners, including partners in the Indian subcontinent, East Africa, West Africa and Brazil, looking at drivers of transmission in specific cutaneous and visceral leishmaniasis foci and designing studies to assess the relevance of sand fly gut microbiota and longevity in disease prevalence and pathogenicity. The group is also developing markers of exposure to specific vectors and will assess their efficacy as a surveillance tool to be used in monitoring human-vector contact in endemic populations during interventions. Main collaborators are Caryn Bern (UCSF), Sridhar Srikantiah (Care India), Abhay Satoskar (OSU), Seydou Doumbia (University of Bamako) and Claudia Brodskyn (FIOCRUZ).
Dr. Kamhawi is a strong advocate for promoting science in NTD countries and has been serving the community as co-editor-in-chief for PLOS Neglected Tropical Diseases.
DeSouza-Vieira T, Iniguez E, Serafim TD, de Castro W, Karmakar S, Disotuar MM, Cecilio P, Lacsina JR, Meneses C, Nagata BM, Cardoso S, Sonenshine DE, Moore IN, Borges VM, Dey R, Soares MP, Nakhasi HL, Oliveira F, Valenzuela JG, Kamhawi S. Heme Oxygenase-1 Induction by Blood-Feeding Arthropods Controls Skin Inflammation and Promotes Disease Tolerance. Cell Rep. 2020 Oct;33(4):108317.
Coutinho-Abreu IV, Oristian J, de Castro W, Wilson TR, Meneses C, Soares RP, Borges VM, Descoteaux A, Kamhawi S, Valenzuela JG. Binding of Leishmania infantum Lipophosphoglycan to the Midgut Is Not Sufficient To Define Vector Competence in Lutzomyia longipalpis Sand Flies. mSphere. 2020 Sep;5(5):e00594-20.
Oliveira F, Giorgobiani E, Guimarães-Costa AB, Abdeladhim M, Oristian J, Tskhvaradze L, Tsertsvadze N, Zakalashvili M, Valenzuela JG, Kamhawi S. Immunity to vector saliva is compromised by short sand fly seasons in endemic regions with temperate climates. Sci Rep. 2020 May;10(1):7990.
Hotez PJ, Aksoy S, Brindley PJ, Kamhawi S. What constitutes a neglected tropical disease? PLoS Negl Trop Dis. 2020 Jan;14(1):e0008001.
Serafim TD, Coutinho-Abreu IV, Oliveira F, Meneses C, Kamhawi S, Valenzuela JG. Sequential blood meals promote Leishmania replication and reverse metacyclogenesis augmenting vector infectivity. Nat Microbiol. 2018 May;3(5):548-555.
Dey R, Joshi AB, Oliveira F, Pereira L, Guimarães-Costa AB, Serafim TD, de Castro W, Coutinho-Abreu IV, Bhattacharya P, Townsend S, Aslan H, Perkins A, Karmakar S, Ismail N, Karetnick M, Meneses C, Duncan R, Nakhasi HL, Valenzuela JG, Kamhawi S. Gut Microbes Egested during Bites of Infected Sand Flies Augment Severity of Leishmaniasis via Inflammasome-Derived IL-1β. Cell Host Microbe. 2018 Jan;23(1):134-143.e6.
- Evaluating the Safety and Immunogenicity of AGS-v PLUS, a Universal Mosquito-Borne Disease and Mosquito Control Vaccine: NCT04009824
- Safety and Immunogenicity of a First-in-Human Mosquito Saliva Peptide Vaccine; ClinicalTrials.gov Identifier: NCT03055000
- Defining Skin Immunity of a Bite of Key Insect Vectors in Humans; ClinicalTrials.gov Identifier: NCT03641339
Fischer L, Kamhawi S, Valenzuela J, Suau HA, inventors; The United States of America as represented by the Secretary of the Department of Health and Human Services, assignee. Leishmania challenge model. United States patent US 8,906,358. 9 December 2014.
Valenzuela JG, Belkaid Y, Kamhawi S, Sacks D, Ribeiro JMC, inventors; The United States of America as represented by the Secretary of the Department of Health and Human Services, assignee. Anti-arthropod vector vaccines, methods of selecting and uses thereof. United States patent US 7,964,576. 21 June 2011.
Valenzuela JG, Ribeiro JMC, Kamhawi S, Belkaid Y, Fischer L, Audonnet JC, Milward F, inventors; The United States of America as represented by the Department of Health and Human Services, Merial Limited, assignees. P. ariasi polypeptides, p. perniciosuspolypeptides and methods of use. United States patent US 7,741,437. 22 Jun 2010.
Valenzuela JG, Belkaid Y, Kamhawi S, Sacks D, Ribeiro JMC, inventors; The United States of America as represented by the Department of Health and Human Services, assignee. Anti-arthropod vector vaccines, methods of selecting and uses thereof. United States patent US 7,388,089. 17 Jun 2008.
Participating Research Networks
- The University of Texas Medical Branch, Galveston
- University of California, San Francisco
- Ohio State University
- Uniformed Services University of the Health Sciences
- Yale School of Public Health
- University of Iowa
- Care India, India
- University of Bamako, Mali
- CPqGM – FIOCRUZ, Brazil
- Pasteur Institute of Tunis, Tunisia