Background Phlebotomine sand flies are blood-sucking insects that can transmit Leishmania parasites. Hosts bitten by sand flies develop an immune response against sand fly salivary antigens. Specific anti-saliva IgG indicate the exposure to the vector and may also help to estimate the risk of Leishmania spp. transmission. In this study, we examined the canine antibody response against the saliva of Phlebotomus perniciosus, the main vector of Leishmania infantum in the Mediterranean Basin, and characterized salivary antigens of this sand fly species. Methodology/Principal Findings Sera of dogs bitten by P. perniciosus under experimental conditions and dogs naturally exposed to sand flies in a L. infantum focus were tested by ELISA for the presence of anti-P. perniciosus antibodies. Antibody levels positively correlated with the number of blood-fed P. perniciosus females. In naturally exposed dogs the increase of specific IgG, IgG1 and IgG2 was observed during sand fly season. Importantly, Leishmania-positive dogs revealed significantly lower anti-P. perniciosus IgG2 compared to Leishmania-negative ones. Major P. perniciosus antigens were identified by western blot and mass spectrometry as yellow proteins, apyrases and antigen 5-related proteins. Conclusions Results suggest that monitoring canine antibody response to sand fly saliva in endemic foci could estimate the risk of L. infantum transmission. It may also help to control canine leishmaniasis by evaluating the effectiveness of anti-vector campaigns. Data from the field study where dogs from the Italian focus of L. infantum were naturally exposed to P. perniciosus bites indicates that the levels of anti-P. perniciosus saliva IgG2 negatively correlate with the risk of Leishmania transmission. Thus, specific IgG2 response is suggested as a risk marker of L. infantum transmission for dogs.
References
[1]
Gramiccia M, Gradoni L (2005) The current status of zoonotic leishmaniases and approaches to disease control. Int J Parasitol 35: 1169–1180. doi: 10.1016/j.ijpara.2005.07.001
[2]
Miró G, Cardoso L, Pennisi MG, Oliva G, Baneth G (2008) Canine leishmaniosis – new concepts and insights on an expanding zoonosis: part two. Trends Parasitol 24: 371–377. doi: 10.1016/j.pt.2008.05.003
[3]
Molina R, Amela C, Nieto J, Sanandres M, Gonzalez F, et al. (1994) Infectivity of dogs naturally infected with Leishmania infantum to colonized Phlebotomus perniciosus. Trans R Soc Trop Med Hyg 88: 491–493. doi: 10.1016/0035-9203(94)90446-4
[4]
Otranto D, Paradies P, de Caprariis D, Stanneck D, Testini G, et al. (2009) Toward diagnosing Leishmania infantum infection in asymptomatic dogs in an area where leishmaniasis is endemic. Clin Vaccine Immunol 16: 337–343. doi: 10.1128/CVI.00268-08
[5]
Maroli M, Bigliocchi F, Khoury C (1994) Sandflies in Italy: observations on their distribution and methods for control. Parassitologia 36: 251–264.
[6]
Kilick-Kendrick R (1999) The biology and control of Phlebotomine sand flies. Clin Dermatol 17: 279–289. doi: 10.1016/S0738-081X(99)00046-2
[7]
Hostomska J, Rohousova I, Volfova V, Stanneck D, Mencke N, et al. (2008) Kinetics of canine antibody response to saliva of the sand fly Lutzomyia longipalpis. Vector Borne Zoonotic Dis 8: 443–450. doi: 10.1089/vbz.2007.0214
[8]
Gomes RB, Mendon？a IL, Silva VC, Ruas J, Silva MB, et al. (2007) Antibodies against Lutzomyia longipalpis saliva in the fox Cerdocyon thous and the sylvatic cycle of Leishmania chagasi. Trans R Soc Trop Med Hyg 101: 127–133. doi: 10.1016/j.trstmh.2006.06.002
[9]
Oliveira F, Jochim RC, Valenzuela JG, Kamhawi S (2009) Sand flies, Leishmania, and transcriptome-borne solutions. Parasitol Int 58: 1–5. doi: 10.1016/j.parint.2008.07.004
[10]
Baneth G, Koutinas AF, Solano-Gallego L, Bourdeau P, Ferrer L (2008) Canine leishmaniosis-new concepts and insights on an expanding zoonosis:part one. Trends Parasitol 24: 324–330. doi: 10.1016/j.pt.2008.04.001
[11]
Collin N, Gomes R, Teixeira C, Cheng L, Laughinghouse A, et al. (2009) Sand fly salivary proteins induce strong cellular immunity in a natural reservoir of visceral leishmaniasis with adverse consequences for Leishmania. PLoS Pathog 5: e1000441. doi: 10.1371/journal.ppat.1000441
[12]
Volf P, Volfova V (2011) Establishment and maintenance of sand fly colonies. J Vector Ecol 36: S1–S9. doi: 10.1111/j.1948-7134.2011.00106.x
[13]
Mencke N, Volf P, Volfova V, Stanneck D (2003) Repellent efficacy of a combination containing imidacloprid and permethrin against sand flies (Phlebotomus papatasi) on dogs. Parasitol Res 90: S108–S111. doi: 10.1007/s00436-003-0905-7
[14]
Tarallo VD, Dantas-Torres F, Lia RP, Otranto D (2010) Phlebotomine sand fly population dynamics in a leishmaniasis endemic peri-urban area in southern Italy. Acta Trop 116: 227–234. doi: 10.1016/j.actatropica.2010.08.013
[15]
Otranto D, de Caprariis D, Lia RP, Tarallo V, Lorusso V, et al. (2010) Prevention of endemic canine vector-borne diseases using imidacloprid 10% and permethrin 50% in young dogs: a longitudinal field study. Vet Parasitol 172: 323–332. doi: 10.1016/j.vetpar.2010.05.017
[16]
Otranto D, Paradies P, de Caprariis D, Stanneck D, Testini G, et al. (2009) Toward diagnosing Leishmania infantum infection in asymptomatic dogs in an area where leishmaniasis is endemic. Clin Vaccine Immunol 16: 337–343. doi: 10.1128/CVI.00268-08
[17]
Anderson JM, Oliveira F, Kamhawi S, Mans BJ, Reynoso D, et al. (2006) Comparative salivary gland transcriptomics of sandfly vectors of visceral leishmaniasis. BMC Genomics 7: a.n. 52.
[18]
Gerstman BB (2003) Epidemiology kept simple: an introduction to traditional and modern epidemiology. Willey-Liss, Hoboken, New Yersey. 417 p.
[19]
Katz J, Baptista J, Azen SP, Pike MC (1978) Obtaining confidence intervals for the risk ratio in cohort studies. Biometrics 34: 469–474. doi: 10.2307/2530610
[20]
Mazza G, Whiting AH, Day MJ, Duffus WPH (1994) Development of an enzyme-linked immunosorbent assay for the detection of IgG subclasses in the serum of normal and diseased dogs. Res Vet Sci 57: 133–139. doi: 10.1016/0034-5288(94)90048-5
[21]
Rohousova I, Volf P (2006) Sand fly saliva: effects on host immune response and Leishmania transmission. Folia Parasitol 53: 161–171.
[22]
Rohousova I, Ozensoy S, Ozbel Y, Volf P (2005) Detection of species-specific antibody response of humans and mice bitten by sand flies. Parasitology 130: 493–499. doi: 10.1017/S003118200400681X
[23]
de Moura TR, Oliveira F, Novais FO, Miranda JC, Clarencio J, et al. (2007) Enhanced Leishmania braziliensis Infection Following Pre-Exposure to Sandfly Saliva. PloS Negl Trop Dis 1: e84. doi: 10.1371/journal.pntd.0000084
[24]
Barral A, Honda E, Caldas A, Costa J, Vinhas V, et al. (2000) Human immune response to sand fly salivary gland antigens: a useful epidemiological marker? Am J Trop Med Hyg 62: 740–745.
[25]
Gomes RB, Brodskyn C, de Oliveira CI, Costa J, Miranda JC, et al. (2002) Seroconversion against Lutzomyia longipalpis saliva concurrent with the development of anti-Leishmania chagasi delayed-type hypersensitivity. J Infect Dis 186: 1530–1534. doi: 10.1086/344733
[26]
Bahia D, Gontijo NF, Leon IR, Perales J, Pereira MH, et al. (2007) Antibodies from dogs with canine visceral leishmaniosis recognise two proteins from the saliva of Lutzomyia longipalpis. Parasitol Res 100: 449–454. doi: 10.1007/s00436-006-0307-8
[27]
Teixeira C, Gomes R, Collin N, Reynoso D, Jochim R, et al. (2010) Discovery of markers of exposure specific to bites of Lutzomyia longipalpis, the vector of Leishmania infantum chagasi in Latin America. PLoS Negl Trop Dis 4: e638. doi: 10.1371/journal.pntd.0000638
