Antibody responses of domestic animals to salivary antigens of Triatoma infestans as biomarkers for low-level infestation of triatomines
Authors: Jeremy M Sternberg
Nora Medrano-Mercado
Jen C C Hume
Jennifer M Anderson
Valerie Johnston
Günter A Schaub
Jesus G Valenzuela
Peter F Billingsley
Alexandra Schwarz
Journal: International Journal for Parasitology (2009)
Discipline: MICROBIOLOGY
Keywords: Hematophagous arthropods; Triatoma infestans; Trypanosoma cruzi; antibody responses; salivary antigens
Affiliations: School of Biological Sciences, Zoology Building, University of Aberdeen, Aberdeen, UK. 

Abstract:  Hematophagous arthropods such as Triatoma infestans, the vector of Trypanosoma cruzi, elicit host-immune responses during feeding. Characterization of antibody responses to salivary antigens offers the potential to develop immunologically based monitoring techniques for exposure to re-emergent triatomine bug populations in peridomestic animals. IgG-antibody responses to the salivary antigens of T.infestans have been detected in chickens as soon as 2 days after the first exposure to five adult bugs. Chickens and guinea pigs regularly exposed to this number of triatomines showed a significantly lower anti-saliva antibody titre than animals exposed to 25 adults and fifth instars of four different T.infestans strains originating from Bolivia and from Northern Chile. Highly immunogenic salivary antigens of 14 and 21kDa were recognised by all chicken sera and of 79kDa by all guinea pig sera. Cross-reactivity studies using saliva or salivary gland extracts from different hematophagous species, e.g. different triatomines, bed bugs, mosquitoes, sand flies and ticks, as well as chicken sera exposed to triatomines and mosquitoes, demonstrated that the 14 and 21kDa salivary antigens were only found in triatomines. Sera from peridomestic chickens and guinea pigs in sites of known T.infestans challenge in Bolivia also recognised the 14 and 21kDa antigens. These represent promising epidemiological markers for the detection of small numbers of feeding bugs and hence may be a new tool for vector surveillance in Chagas disease control programs. 

Retracted: No

PubPeer comments:
 Figure 2. The high MW parts of lane  Coch and lane  PaSo appear to look unexpectedly similar to each other. Note the presence of a white spot left under the top band, and a black spot in the lowest band of the marked region. Marked with red boxes. ![file] , 
 Figure 3. Several areas in the lanes look unexpectedly similar to each other. Could the authors please check? ![file] , 
 Dear Elizabeth Apologies for the slow response. I never look at PubPeer and your posting was only brought to my attention a short time ago. I have taken a look at your comments and the images that you have highlighted. Figure 2: I do see your point concerning the similarity. As I no longer have access a hard copy of the thesis, my response involved simply blowing up these images as best as I could on my monitor, cropping the two images that you outlined so that they could be placed next to one another. I see enough variation between the two that satisfies me that these patterns are real. Figure 3: I tried the same thing with this and for the life of me cannot see the issues you are raising except, perhaps, in the two green circles where the three white spots look very similar indeed between the two lanes. I can only think that these are introduced during scanning somehow. There are sufficient differences between lanes, including marks running across the lanes, to demonstrate that there is no manipulation of the images here. Best Peter (on behalf of all authors) , 
 For Figure 2, I adjusted the contrast on the rightmost lane marked by Dr. Bik to attempt to match the area in the first lane. I agree with her that these are likely to share the same source, but may have been edited to appear different. There are numerous features that appear identical to my eye. *** ![file] ,