Chagas disease vector blood meal sources identified by protein mass spectrometry

Abstract

Chagas disease is a complex vector borne parasitic disease involving blood feeding Triatominae (Hemiptera: Reduviidae) insects, also known as kissing bugs, and the vertebrates they feed on. This disease has tremendous impacts on millions of people and is a global health problem. The etiological agent of Chagas disease, Trypanosoma cruzi (Kinetoplastea: Trypanosomatida: Trypanosomatidae), is deposited on the mammalian host in the insect’s feces during a blood meal, and enters the host’s blood stream through mucous membranes or a break in the skin. Identifying the blood meal sources of triatomine vectors is critical in understanding Chagas disease transmission dynamics, can lead to identification of other vertebrates important in the transmission cycle, and aids management decisions. The latter is particularly important as there is little in the way of effective therapeutics for Chagas disease. Several techniques, mostly DNA-based, are available for blood meal identification. However, further methods are needed, particularly when sample conditions lead to low-quality DNA or to assess the risk of human cross-contamination. We demonstrate a proteomics-based approach, using liquid chromatography tandem mass spectrometry (LC-MS/MS) to identify host-specific hemoglobin peptides for blood meal identification in mouse blood control samples and apply LC-MS/MS for the first time to Triatoma dimidiata insect vectors, tracing blood sources to species. In contrast to most proteins, hemoglobin, stabilized by iron, is incredibly stable even being preserved through geologic time. We compared blood stored with and without an anticoagulant and examined field-collected insect specimens stored in suboptimal conditions such as at room temperature for long periods of time. To our knowledge, this is the first study using LC-MS/MS on field-collected arthropod disease vectors to identify blood meal composition, and where blood meal identification was confirmed with more traditional DNA-based methods. We also demonstrate the potential of synthetic peptide standards to estimate relative amounts of hemoglobin acquired when insects feed on multiple blood sources. These LC-MS/MS methods can contribute to developing Ecohealth control strategies for Chagas disease transmission and can be applied to other arthropod disease vectors.

Rapid detection of human blood in triatomines (kissing bugs) utilizing a lateral flow immunochromatographic assay - A pilot study

“… 13 However, false-positive detection of human DNA not acquired from a blood meal is an important limitation of this detection methodology. 5 A study conducted by Keller et al 7 compared the effectiveness of short interspersed nuclear elements (SINE)-based PCR and liquid chromatography tandem mass spectrometry (LC-MS/MS) in laboratory-raised T. protracta in detection of laboratory mouse ( Mus musculus ) hemoglobin and albumin from a blood meal. LC-MS/MS was able to detect mouse hemoglobin up to four weeks post-feeding and 12 weeks post-molting in T. protracta whereas, the DNA-based detection technique using mouse-specific SINE-DNA was able to detect mouse blood up to one-week post-feeding, and did not detect mouse blood in the post-molt triatomines.…”

“… 2 Several techniques have been developed using DNA- and proteomics-based methodologies in an attempt to determine the blood meal sources of triatomines. 3 , 4 , 5 , 6 , 7 These procedures are sensitive and specific for identifying a blood meal source, but are not readily adaptable to field use. They require access to a laboratory with sophisticated equipment and trained personnel, are labor intensive, and are vulnerable to contamination and degradation of the blood meal.…”

“…They require access to a laboratory with sophisticated equipment and trained personnel, are labor intensive, and are vulnerable to contamination and degradation of the blood meal. 3 , 4 , 5 , 6 , 7 The Rapid Stain Identification of Human Blood (RSID™ Blood) is a lateral flow, immunochromatographic assay detecting as little as 1 µL of human blood in forensic samples within 10 min following 1-2 h of specimen preparation. We conducted a preliminary study using this assay on triatomines and their excreta fed mouse or human blood and also numerous field specimens.…”

Implementation science: Epidemiology and feeding profiles of the Chagas vector Triatoma dimidiata prior to Ecohealth intervention for three locations in Central America

“…As mentioned before, the lack of blood source detection by PCR can indicate either a recent blood meal from taxa not included in the survey or no recent blood meal [4,20,41]. Strong support for no recent blood meal is provided by recent studies based on mass spectrometry [54,55] including domestic vectors from El Salvador that show DNA based methods have a short window for blood meal detection [54], it would be interesting to examine T. dimidiata where no blood sources were detected by PCR from these three localities to strengthen the Ecohealth strategies proposed by this study.…”

Protein mass spectrometry extends temporal blood meal detection over polymerase chain reaction in mouse-fed Chagas disease vectors

“…Recently, we have shown the usefulness of a protein-based method based on liquid chromatography tandem mass spectrometry (LC-MS/MS) for blood meal source identification. 29 A few studies have compared different methodologies directly. For example, Lucero et al compared 12 S sequencing and qPCR, 30 while Stevens et al compared 12 S sequencing and cytochrome b.…”