Iranian Journal of Parasitology
Volume:4 Issue: 3, Jul-Sep 2009

Leishmania is an obligatory intracellular protozoan parasite, which infects human be­ings when infected sand fly vector takes a blood meal. Most efforts are towards designing an effective vaccine to prevent leishmaniasis. In this way, development of candidate antigen for vaccine has spe­cial im­portant. In this study, we cloned mannose-1-phosphate guanyltransferase gene of Iranian L. major in pET32a expression vector. Primers based on L. major mannose-1-phosphate guanyltransferase sequence gene was de­signed and synthesized. DNA of Leishmania promastigotes was extracted and PCR reaction was done. PCR product was cloned into pTZ57R and sub cloned into pET32a expression vector. Recombinant plasmid containing 1140 bp as L. major mannose-1-phosphate guanyltrans­ferase gene was extracted and confirmed by restriction analysis. PCR product was sequenced and de­posited to GenBank. There were some differences in amino acid sequences between Iranian L. major mannose-1-phosphate guanyltransferase and others previously accepted in GenBank We amplified and cloned Iranian L. major mannose-1-phosphate guanyltransferase suc­cessfully.

The aim of this study was to determine the prevalence, intensity, and species of internal and external parasites of native fowls from Golestan Province, north of Iran. During 2007, different organs of 26 and 24 adult female native fowls collected from hu­mid parts (Gorgan, Kord Kooy, Ramian and Bandar Gaz) and dry regions (Gonbad Kavoos, and Ban­dar Torkaman) of Golestan Province, respectively were searched for parasite. Two blood smears taken from each bird were stained with Geimsa. External parasites and nematodes were preserved in 70 % alcohol containing 5% glycerin. Cestodes were fixed in 10% formalin and stained with carmine acid for further studies. Fifteen species of parasites were collected from alimentary canals, lungs, feathers and subcu­ta­neous nodules as follows: Alimentary canal: Ascaridia galli (56%), Heterakis gallinarum (24%), Capil­laria anatis (4%), Cheilospirura hamulosa (4%), Raillietina tetragona (58%), R. echinobothrida (6%), and Choanotaenia infundibulum (8%); Lungs: Syngamus trachea (16%); Feathers: Monopon gallinae (40%), Menacanthus stramineus (40%), Liperus caponis (32%), Goniodes dissimilis (38%), Cuclogaster heterographus (8%), Dermanissus gallinae (20%) and subcutaneous nodules: Lami­nosioptes cysticola (6%). The frequency distribution of most species was low. L. cysticola is the first host and distri­bution record for Iran

Cryptosporidium parvum is a parasitic protozoan that functions as important causa­tive agent of diarrhea in human and animals. The host''s immune response to surface anti­gens of C. parvum has been previously demonstrated. In this respect, the role of humoral immu­nity in the development of host protective immunity against this protozoon has been well demon­strated. The effect of specific chicken egg yolk antibody (IgY) against recombinant C. parvum P23 was examined. IgY sample was prepared from eggs of chickens immunized with recombi­nant C. parvum protein p23 and analyzed with C. parvum lysate and recombinant P23. The anti P23 specific IgY was recognized a protein band with approximately 23 kDa in lys­ates prepared from the C. parvum oocysts. Also dot blot analysis of recombinant P23 showed that it could be recognized by the anti P23 specific IgY up to 1/1000 dilution of antibody. But the best antibody dilution for immunological studies was determined as 1:200. Since P23 is an immunodominant surface glycoprotein expressed in the early phase of infection, specific IgY against recombinant p23 could be recommended as a favorable candi­date for passive immunization against C. parvum infection in human and animals.

Linguatulosis is a rare zoonotic parasitic infection, in which human plays the role of both defini­tive and intermediate host and can be occasionally infected. This study determines the status of infection in live­stock and its po­tential risk to men in the northwestern province of Azarbaijan-e-Sharghi, Iran. In a cross-sectional study from June 2007 to June 2008, 800 slaughtered animals including 400 cattle and 400 buffaloes from Tabriz abattoir in Azarbaijan-e-Sharghi Province were randomly selected and examined for L. serrata nymphs. After primary macroscopical inspection, all liver and lung samples were cut to small pieces, treated with a tissue digestion method and checked macroscopically and micro­scopically for free or encapsulated nymphs. Out of 800 animals, 3 (0.38%) were found to be infected with L. serrata nymphs and the preva­lence of infection in cattle and buffaloes was determined to be 0.25% and 0.5%, respectively. Linguatula infection occurs as an endemic zoonosis in the study area and has an active transmission life cycle.

Antiself humoral immune responses have been detected not only in classical autoimmune dis­eases, but autoantibodies have also been found in sera of patients suffering from chronic parasitic dis­eases. We aimed to investigate the role of fasciolosis as a trigger factor of autoimmune reactivity by searching some anti­bodies related to hepatobiliary systems, in patients with fasciolosis. Thirty-two patients (17 males, 15 females) with fasciolosis were included in this case-control study. Anti-nuclear antibodies (ANA) Screen (antigen mixture of dsDNA, histones, nRNP/Sm, Sm, SS-A, SS-B, Scl-70, Jo-1, ribosomal P-proteins, centromere) ELISA and single-antigen ELISAs for detection of some antibodies (dsDNA, Anti-M2, Anti- liver-kidney microsomes type 1 (LKM-1) and Myeloperoxidase (MPO) were carried out. ANA-screen, M-2, LKM-1, MPO and anti-dsDNA positivity were detected with ELISA in 7, 7, 4, 2 and 2 of 32 patients with fasciolosis, consecutively. No statistically significant difference was de­tected for any of the autoantibodies'' frequency between patients with fasciolosis and control group. How­ever, autoantibody positivity rate was significantly higher in patients with fasciolosis (50 %) than control group (12.5 %). Absorbance values of all autoantibodies in patients with fasciolosis were statistically sig­nificant higher than controls. These results lent support to the role of fasciolosis as a trigger factor of autoimmune reactiv­ity by the breakdown of tolerance. In spite of the extensive knowledge that has accumulated, the specific relationship be­tween fasciolosis and autoimmunity is still obscure.

The objective of the study was to evaluate the presence of Neospora caninum organisms in the brain of aborted fetuses and placentas of full-term calves born of seropositive cows. During 2006-2007, 12 brains of aborted calves from Neospora seropositive cattle and 7 pla­centas from seropositive dams giving birth to full-term calves, from four dairy cattle farms located around Tehran province, Iran were examined by Nested-PCR and histopathology techniques. The Nested-PCR demonstrated that all of 12 aborted fetal brain samples and 5 of 7 placentas were infected by N. caninum. Mild to severe placentitis was observed in 5 placentas. Severe hyperemia and pe­rivascular and perineuronal edema revealed in all fetal brain. In 3 out of 12 brains, scattered foci of he­morrhages, neuropilar necrosis and gliosis were present. In addition, nonpurulent encephalitis with severe lymphohistiocytic perivascular cuffing in one case and a small tissue cyst like Neospora caninum cyst in other calf were observed. Our results confirmed the molecular and histopathologic findings of other studies about Neos­pora caninum infection and it seems to support the hypothesis that Neospora infection is associated with bovine abortion in Iran.

The aim of this study was to characterize the Leishmania parasites isolated from cuta­neous leishmaniasis (CL) patients in Fars Province in Iran and to compare the potential infectivity of the isolates in macrophage cell line. Moreover, attempt was made to find out the association between parasite infectivity and their zymodems. Twenty samples were taken from the skin lesion of CL patients. The samples were cultured in biphasic media followed by mass cultivation in RPMI medium. Each isolate was tested for the ac­tivity of the 5 enzymes including glucose phosphate isomerase (GPI), malate dehydrogenase (MDH), nucleoside hydrolase 1& 2 (NH1 & NH2), and phosphoglucomutase (PGM). The enzymatic profiles of the isolates were compared with WHO reference strains. Specific PCR (primers: LIN17 & LIN R4) and RAPD-PCR were used as complementary methods for characterization of the isolates. Isoenzyme electrophoresis showed that all of the isolates were L. major. PCR with LIN17 and LIN R4 and RAPD-PCR with AB-07 primers further determined the isolates as L. major. Results of macrophage infectivity experiment, using J774 cell line, showed that the most virulent isolates were related to Z1 with 63% macrophage infectivity rate. A well correlation was found between the infec­tivity rate of the isolates and type of ulcer. Those isolates with high infectivity rate were involved in more severe, ulcerative or erythmatose lesions in CL patients. The most invasive isolates might be a good candidate for immunological studies and for vaccine development.

To identify the fasciolid species by morphometric and molecular methods in Zanjan, north­west of Iran. Adult Fasciola worms (n=584) were obtained from cattle and sheep in Zanjan slaughterhouse in 2007. Living flukes were washed, then worms'' images were taken by 3CCD camera and finally apical zone of each worm was obtained. Morphometric values such as body length, body width, body area, body pe­rimeter and the distance between ventral sucker and posterior end of body were obtained using Auto­CAD image analysis software. Total gDNA was extracted from individual flukes by modified phenol-chloroform method. PCR amplification of ITS2 fragment was performed the isolated DNA samples and the amplicons were consequently subjected to RFLP assay and nucleotide sequencing to distinguish be­tween fasciolid species. Mean of morphometric values in flukes from sheep was greater than those of cattle. Accordingly, the identified species included 31% F. hepatica-like, 7% F. gigantica-like and 62% intermediate forms. How­ever, ITS2 fragment of 535 amplified specimens, showed no variation at the species-specific nucleo­tide sites 230, 340 and 341. The amplified fragment composed of partial 5.8S sequence (62bp), the com­plete ITS2 sequence (361bp) and partial 28S sequence (34bp). The nucleotide contents of ITS2 region were 69 A, 116 T, 81 C and 95 G and the average G+C content was approximately 49%. Comparing of ITS2 sequences with the BLAST GenBank database, also confirmed that all specimens were F. hepatica. A simple and rapid PCR-RFLP assay can be used for distinguishing between these species.

Cats and other felines act as definitive hosts for many intestinal parasites, some of which are responsible for several zoonotic diseases. The aim of this study was to determine the type and prevalence of protozoa and gastrointestinal helminthes among stray cats. A cross sectional study was conducted. Digestive tracts of 100 stray cats in Zanjan Province, north-west of Iran were autopsied in order to recognize gastrointestinal helminthes and intestinal protozoan parasites. These cats were collected by baited cage trapped from October 2007 to September 2008. Gender and species of helminthes and protozoa were rec­ognized using authentic diagnostic criteria. Statistical evaluation was performed by SPSS version 14. Forty-two percent of cats were infected with intestinal protozoan parasites, 33% were infected with cestodes and 39% infected with gastrointestinal nematodes. Four species protozoan parasites and eight gastrointestinal helminthes were recovered from the animals, including Taenia taeniaeformis, Dipylidium spp., Joyeuxiella pasqaulei, Toxocara cati, Phy­saloptera praeputialis, Rectalaria spp., Onicolla, Cystoisospora spp., Toxoplasma gondii, and Sarcocystis spp. The high infection rate of Toxoplasma and some gastrointestinal helminthes in stray cats is considered to be critical from the viewpoint of public health importance.