Prevalence of Giardia Assemblages Among Equines in Jordan

A cross-sectional study was carried out on 400 equine holding (326 horses and 74 donkeys) samples to determine the prevalence of Giardia assemblages A, B, and E in Jordan. Identifying the Giardia assemblages was carried out using enzyme-linked immunosorbent assay (ELISA) as a screening test and PCR-RFLP targeting β-giardin loci. In addition, polymerase chain reaction targeting triose phosphate isomerase gene specific for assemblages A and B were used as confirmatory. Thirty-four samples tested positive by ELISA for Giardia with an apparent prevalence of 8.5%. The PCR-RFLP test confirmed Giardia assemblages in 30 of the 34 ELISA-positive samples giving a true prevalence of 7.7% (95% confidence interval: 4.8–10.1). Of the 30 positive animals/holdings, 18, 4, and 8 had assemblages A, B, and E. Assemblage A was significantly (P < .05) more prevalent when compared to assemblages B and E. The total infection rates of Giardia, assemblages B and E were significantly (P < .05, chi-square) higher in donkeys 14.8%, 2.7%, and 5.5% compared to horses 5.8%, 0.6%, and 1.2%, respectively. Analysis of risk factors revealed that only season was significantly associated with the different Giardia assemblages. Autumn (odds ratio [OR] = 0.09) was associated with Giardia infection regardless of the assemblage type as reducing factor. The odds of infection of assemblages A and E increased in winter (OR = 6.8) and spring (OR = 4.5), respectively. Giardia assemblages A, B, and E infect both horses and donkeys in Jordan with potential impact on human and animal health, and the odds of infections is significantly associated with season

Profiling of human acquired immunity against the salivary proteins of Phlebotomus papatasi reveals clusters of differential immunoreactivity

Citation: Geraci, Nicholas S., Rami M. Mukbel, Michael T. Kemp, Mariha N. Wadsworth, Emil Lesho, Gwen M. Stayback, Matthew M. Champion, et al. 2014. “Profiling of Human Acquired Immunity Against the Salivary Proteins of Phlebotomus Papatasi Reveals Clusters of Differential Immunoreactivity.” The American Journal of Tropical Medicine and Hygiene 90 (5): 923–38. https://doi.org/10.4269/ajtmh.13-0130.Phlebotomus papatasi sand flies are among the primary vectors of Leishmania major parasites from Morocco to the Indian subcontinent and from southern Europe to central and eastern Africa. Antibody-based immunity to sand fly salivary gland proteins in human populations remains a complex contextual problem that is not yet fully understood. We profiled the immunoreactivities of plasma antibodies to sand fly salivary gland sonicates (SGSs) from 229 human blood donors residing in different regions of sand fly endemicity throughout Jordan and Egypt as well as 69 US military personnel, who were differentially exposed to P. papatasi bites and L. major infections in Iraq. Compared with plasma from control region donors, antibodies were significantly immunoreactive to five salivary proteins (12, 26, 30, 38, and 44 kDa) among Jordanian and Egyptian donors, with immunoglobulin G4 being the dominant anti-SGS isotype. US personnel were significantly immunoreactive to only two salivary proteins (38 and 14 kDa). Using k-means clustering, donors were segregated into four clusters distinguished by unique immunoreactivity profiles to varying combinations of the significantly immunogenic salivary proteins. SGS-induced cellular proliferation was diminished among donors residing in sand fly-endemic regions. These data provide a clearer picture of human immune responses to sand fly vector salivary constituents

Complement Receptor 3 Deficiency Influences Lesion Progression during Leishmania major Infection in BALB/c Mice▿

Leishmania major is an obligately intracellular protozoan parasite that causes cutaneous leishmaniasis. Like numerous intracellular pathogens, Leishmania exploits cell surface receptors as a means of entry into host cells. Complement receptor 3 (CR3; also called CD11b/CD18), a β2 integrin on phagocytic cells, is one such receptor. Ligation of CR3 has been shown to inhibit the production of interleukin-12, the cytokine that is pivotal in establishing the cell-mediated response necessary to combat intracellular infection. Here we investigate the role that CR3 plays in the establishment and progression of cutaneous leishmaniaisis in vivo. Dermal lesions of wild-type BALB/c mice are characteristically progressive and lead to extensive tissue necrosis coupled with elevated parasite burdens; CD11b-deficient BALB/c mice, however, demonstrate an intermediate phenotype characterized by chronic lesions and a reduced incidence of tissue damage. Infection followed by a reinfection challenge indicates that both susceptible (BALB/c) and resistant (C57BL/6) mice, regardless of CD11b status, develop resistance to L. major. In addition, CD11b does not bias the T helper cytokine response to L. major infection. Our results further indicate that CD11b is not necessary for disease resolution in resistant mice; rather, this protein appears to play a minor role in susceptibility

Population genetics analysis of Phlebotomus papatasi sand flies from Egypt and Jordan based on mitochondrial cytochrome b haplotypes

Abstract Background Phlebotomus papatasi sand flies are major vectors of Leishmania major and phlebovirus infection in North Africa and across the Middle East to the Indian subcontinent. Population genetics is a valuable tool in understanding the level of genetic variability present in vector populations, vector competence, and the development of novel control strategies. This study investigated the genetic differentiation between P. papatasi populations in Egypt and Jordan that inhabit distinct ecotopes and compared this structure to P. papatasi populations from a broader geographical range. Methods A 461 base pair (bp) fragment from the mtDNA cytochrome b (cyt b) gene was PCR amplified and sequenced from 116 individual female sand flies from Aswan and North Sinai, Egypt, as well as Swaimeh and Malka, Jordan. Haplotypes were identified and used to generate a median-joining network, F ST values and isolation-by-distance were also evaluated. Additional sand fly individuals from Afghanistan, Iran, Israel, Jordan, Libya, Tunisia and Turkey were included as well as previously published haplotypes to provide a geographically broad genetic variation analysis. Results Thirteen haplotypes displaying nine variant sites were identified from P. papatasi collected in Egypt and Jordan. No private haplotypes were identified from samples in North Sinai, Egypt, two were observed in Aswan, Egypt, four from Swaimeh, Jordan and two in Malka, Jordan. The Jordan populations clustered separately from the Egypt populations and produced more private haplotypes than those from Egypt. Pairwise F ST values fall in the range 0.024–0.648. Conclusion The clustering patterns and pairwise F ST values indicate a strong differentiation between Egyptian and Jordanian populations, although this population structure is not due to isolation-by-distance. Other factors, such as environmental influences and the genetic variability in the circulating Le. major parasites, could possibly contribute to this heterogeneity. The present study aligns with previous reports in that pockets of genetic differentiation exists between populations of this widely dispersed species but, overall, the species remains relatively homogeneous