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Background: Zoonotic cutaneous leishmaniasis (ZCL) is widely distributed in Iran and around the world. Also, Khuzestan Province is an endemic focus of ZCL. This study aims to investigate the natural infection of sand flies with the Leishmania parasite in Karun County. Methods: Sand flies were collected from Jangiyeh, Qaleh Chanan, Kut-e-Navaser, and Ghazavieh in the spring and summer in the year of 2019, by installing 60 sticky paper traps each time (30 traps outdoors and 30 traps indoors). Two hundred female sand flies with different abdominal conditions (empty, blood-fed, semi-gravid, and gravid) were examined for infection rate using the Nested-PCR method. Results: In this study, seven species of sand flies including Phlebotomus papatasi, Ph. alexandri, Ph. sergenti, Ph. caucasicus, Sergentomyia tiberiadis, Se. sintoni, and Se. antennata were reported from Karun County, with a frequency of 79.64%, 16.96%, 1.07%, 0.18%, 0.36%, 1.61%, and 0.18%, respectively. Only eleven specimens of Ph. papatasi were found to be positive for Leishmania major, with an overall infection rate of 7.8%. The infection of Ph. papatasi was specifically reported in blood-fed, gravid, and semi-gravid specimens, with infection rates of 17.02%, 4.35%, and 14.29%, respectively. Conclusion: In this study, the infection of L. major from Ph. papatasi was reported. The results can be used in planning the control of ZCL in the study area. [ABSTRACT FROM AUTHOR]

Background: Stem cell-derived secretome (SE) released into the extracellular space contributes to tissue repair. The present study aimed to investigate the impact of isolated secretome (SE) from adipose-derived mesenchymal stem cells (ASCs) on Leishmania major (L. major) lesions in BALB/c mice. Methods: This experimental study was conducted at Ahvaz University of Medical Sciences (Ahvaz, Iran) in 2021. Forty female BALB/c mice were infected with stationary phase promastigotes through intradermal injection in the bottom of their tail and randomly divided into four groups (n=10 per group). The mice were given SE (20 mg/mL), either alone or in combination with Glucantime (GC, 20 mg/mL/Kg), meglumine antimoniate (20 mg/mL/Kg) for the GC group, and phosphatebuffered saline (PBS) for the control group. After eight weeks, the lesion size, histopathology, the levels of Interleukin 10 (IL- 10), and Interleukin 12 (IL-12) were assessed. For the comparison of values between groups, the parametric one-way ANOVA was used to assess statistical significance. Results: At the end of the experiment, the mice that received SE had smaller lesions (4.56±0.83 mm versus 3.62±0.59 mm, P=0.092), lower levels of IL-10 (66.5±9.7 pg/mL versus 285.4±25.2 pg/mL, P<0.001), and higher levels of IL-12 (152.2±14.2 pg/mL versus 24.2±4.4 pg/mL, P<0.001) than the control. Histopathology findings revealed that mice treated with SE had a lower parasite burden in lesions and spleen than the control group. Conclusion: The current study demonstrated that ADSCderived SE could protect mice infected with L. major against leishmaniasis. [ABSTRACT FROM AUTHOR]

Cutaneous leishmaniasis is one of important parasitic disease in many part of the world. Iran is a hyper endemic area with cutaneous leishmaniasis permanently cause by L.major. Many efforts were conducted to achieve reliable vaccine against leishmaniasis by researches. The goal of this study concentrated on induces protective immunity against cutaneous leishmaniasis in experimental animal using UV-C irradiation promastigotes of L.major. Sixteen Balb/c mice divided to two group included vaccination and control group. The number of 2×106 promastigotes of L.major were exposed to more than 400 J/cm of UV-C irradiation and injected to mice with Freund's complete and incomplete adjuvant. After vaccination, all groups injected SC by 2×106 of wild type of L. major promastigotes in stationary phase. The mice examined weekly for lesion until 2 months. The size of lesions were measured weekly and recorded. Five out of 8 (62.5%) in vaccination group didn't show any lesion after 2 months and the size of lesion in other were significantly smaller than control group (P<0.05). Vaccination against cutaneous leishmaniasis by UV irradiated promastigotes is appropriated for future successful control of leishmaniasis. [ABSTRACT FROM AUTHOR]

Background: Leishmaniasis is a parasitic disease caused by different species of Leishmania parasites with a wide range of clinical manifestations. Antimonial compounds such as meglumine antimoniate (glucantime) are the first line drugs for the treatment of leishmaniasis. However, according to reports of the drug resistance of parasites, the efficacy of antimonial compounds is low. The ATP-binding cassette (ABC) proteins are present in all organisms and mediate the transport of vital elements through biological membranes. One of the important mechanisms of resistance in Leishmania parasites is the overexpression of ABC efflux pumps. P-glycoprotein A (pgpA) is a related gene for ABC transporter in Leishmania species. The aim of this study was to compare the pgpA expression in laboratory-induced resistant L. major (MRHO/IR/75/ER) and sensitive parasites. Methods: RNA extraction of promastigotes of sensitive and resistant clones was performed and total RNA was reverse transcribed. The real-time quantitative polymerase chain reaction (PCR) was used to assess RNA expression profiles and the expression levels were calculated using 2-ΔCt method. Results: The mean expression level of pgpA mRNA was 2.70 ± 0.51 in in sensitive Leishmania clone and 6.08 ± 1.50 in resistant Leishmania clone (P = 0.021). Conclusion: The expression of pgpA gene in resistant strains of L. major was almost fivefold higher than those in susceptible strains. Therefore, this can be used in field isolates, i.e. overexpression of the gene can prove resistance in wild type field isolates. [ABSTRACT FROM AUTHOR]

Background: Leishmania is a genus of trypanosomatid protozoa which causes a wide spectrum of diseases ranging from a self-healing cutaneous lesion to a vital visceral form of the disease. Although various experimental Leishmania vaccines have been prepared in different parts of the world, only a few of first generation vaccines have reached to human trials. Killed Leishmania major (KLM) and autoclaved Leishmania major (ALM) have been tested in human volunteers in Iran and other countries. We evaluated protein contents of KLM and ALM and fresh Leishmania major using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Methods: Leishmania major (MRHO/IR/75/ER) was isolated from infected BALB/c mice and cultured in Novy-MacNeal-Nicolle medium. It was then subcultured in Roswell Park Memorial Institute (RPMI) 1640 medium supplemented with fetal calf serum 20%. ALM and KLM were prepared by Razi Vaccine and Serum Institute of Iran. Electrophoresis of the two antigens and freshly cultured Leishmania major promastigotes was performed and their protein contents were compared using SDS-PAGE. Findings: The results of electrophoresis showed numerous bands from more than 100 kilodalton (kD) to less than 10 kD. KLM bands were found to be similar to freshly cultured intact Leishmania major (except for 57 and 24 kD bands). ALM contained two very close bands (71 kD) which were not seen in KLM or fresh Leishmania major. Conclusion: Identification and purification of protective immunogens in crude antigens and detection of their stability are essential in production of an effective vaccine. [ABSTRACT FROM AUTHOR]