Circulation of Trypanosoma evansi antibodies and risk variables among dromedary camels in Al Batinah governorates, Sultanate of Oman

Al-Harrasi, Mazen; Al-Habsi, Khalid; Ali, Haytham; Al-Marzooqi, W.; Al-Kharousi, Kaadhia; Al-Hamrashdi, Abeer; El-Tahir, Hatim Ali; Elshafie, Elshafie I.

doi:10.1016/j.vprsr.2023.100863

Cited by 2 publications

(2 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The development of effective T. evansi vaccines requires a better understanding of the pathological and immunological mechanisms involved in Surra. Studies on the immune response of camels to T. evansi are still limited to serological detection of specific antibodies in the serum of infected animals (Al-Harrasi et al, 2023;Habeeba et al, 2022), while the role of the cellular immune response has not been investigated so far. The main objective of the present study was, therefore, to investigate the modulatory effects of T. evansi antigens on the differentiation of monocytes into monocyte-derived macrophages in the dromedary camel.…”

Section: Introductionmentioning

confidence: 99%

The Modulation of in Vitro Differentiation of Monocyte-derived Macrophage by Trypanosoma evansi Antigens in the Dromedary Camel

AL-Hilal,

Alkuwayti,

Alrabiah

et al. 2023

WVJ

View full text Add to dashboard Cite

Studies on the camel immune response to Trypanosoma (T.) evansi, the causative agent of Surra, are very limited. In the present study, flow cytometry was employed to investigate the modulatory effects of different T. evansi antigens on the in vitro differentiation of camel blood monocytes into macrophages. For this, in vitro, separated camel monocytes were differentiated into monocyte-derived macrophages (MDM) in the presence or absence (control) of formalin-fixed (inactivated) T. evansi whole parasite (T. evansi group) or the purified Ro Tat 1.2 antigen (Ro Tat 1.2 group). The analysis of the antimicrobial functions of MDM (phagocytosis and reactive oxygen species (ROS) production) revealed reduced phagocytosis activity of camel MDM generated in the presence of T. evansi antigens. In addition, a lack of ROS-response was observed in camel MDM generated in the presence of T. evansi antigens after stimulation with PMA. These results indicated a compromising effect of T. evansi on the innate defense mechanisms in camels. Phenotypic analysis revealed the upregulation of major histocompatibility complex (MHC) class II molecules together with the lower abundance of the scavenger receptor for haptoglobin–hemoglobin complexes (CD163) on MDM generated in the presence of whole T. evansi parasites, indicating a polarizing effect of T. evansi on the differentiation of camel monocytes into an M1 phenotype. However, the reduced antimicrobial functions of these cells argue against their pro-inflammatory nature. Although both MDM generated in the presence of whole T. evansi antigens or their purified Ro Tat 1.2 proteins indicated similar expression levels of CD14 and MHCII molecules, the different abundance of the cell surface molecules CD172a, CD163, CD45, and CD44 indicated different phenotypes of the two MDMs. The results of the present study revealed compromising effects of T. evansi antigens on camel macrophages differentiated in vitro from blood monocytes. Whether these effects contribute to the in vivo pathogenesis of T. evansi in camels remains to be determined in future studies.

show abstract

Section: Introductionmentioning

confidence: 99%

The Modulation of in Vitro Differentiation of Monocyte-derived Macrophage by Trypanosoma evansi Antigens in the Dromedary Camel

AL-Hilal,

Alkuwayti,

Alrabiah

et al. 2023

WVJ

View full text Add to dashboard Cite

show abstract

“…The lack of effective vaccines against trypanosomal infections [23], together with the increased development of drug-resistant strains, strengthens the need for a better understanding of the pathological and immunological mechanisms involved in Trypanosoma infections, paving the way for the development of prophylactic vaccines. Studies on the immune response of camels to T. evansi are still limited to serological detection of specific antibodies in the serums of infected animals [24,25], while the role of the cellular immune response has not been investigated so far. The aim of the present study was to investigate the impact of in vitro stimulation with inactivated T. evansi on selected functions of camel leukocytes.…”

Section: Introductionmentioning

confidence: 99%

A Flow Cytometry Study of the Binding and Stimulation Potential of Inactivated Trypanosoma evansi toward Dromedary Camel Leukocytes

Hussen,

AL-Jabr,

Alkuwayti

et al. 2023

Pathogens

View full text Add to dashboard Cite

Surra, a wasting disease caused by Trypanosoma evansi, is one of the major animal health burdens in camel-rearing countries, imposing significant economic losses due to reduced fertility and high mortality rates. The present study used inactivated T. evansi (from the Card Agglutination Test for Trypanosomes/Trypanosoma evansi; CATT/T. evansi) and flow cytometry to investigate their binding and activation potential toward camel leukocyte subsets. Labeling T. evansi with propidium iodide (PI) enabled their flow cytometric enumeration and identification with forward scatter (FSC; indicative for cell size) and side scatter (SSC; indicative for cell internal complexity) characteristics that are comparable with values reported for Trypanosoma cruzi. The incubation of PI-labeled non-opsonized T. evansi with camel leukocyte populations revealed that camel monocytes have the highest potential to bind T. evansi, followed by granulocytes and lymphocytes. The identification of pattern recognition receptors (PRRs) on camel immune cells and the pathogen-associated molecular patterns (PAMPs) in T. evansi that are responsible for this different binding capacity requires further studies. Stimulation of camel neutrophils with Trypanosoma evansi induced shape change, reactive oxygen species (ROS) production, and neutrophil extracellular traps (NET)-formation. To ensure that T. evansi, in the parasite concentration used in this study, is not apoptotic or necrotic to camel leukocytes, we evaluated cell apoptosis and necrosis after stimulation with T. evansi. The results revealed no impact of T. evansi stimulation for 2 h on the cell viability of camel leukocytes. Subsequent work may focus on the diagnostic employment of labeled T. evansi and flow cytometry for the detection of anti-Trypanosoma antibodies in camel serum. In addition, more efforts should be deployed to investigate the host–pathogen interaction mechanisms and the escape mechanisms of T. evansi in camels. To complete these data, further studies using the living or freshly killed parasites could also be implemented in camels and/or horses.

show abstract

Circulation of Trypanosoma evansi antibodies and risk variables among dromedary camels in Al Batinah governorates, Sultanate of Oman

Cited by 2 publications

References 18 publications

The Modulation of in Vitro Differentiation of Monocyte-derived Macrophage by Trypanosoma evansi Antigens in the Dromedary Camel

The Modulation of in Vitro Differentiation of Monocyte-derived Macrophage by Trypanosoma evansi Antigens in the Dromedary Camel

A Flow Cytometry Study of the Binding and Stimulation Potential of Inactivated Trypanosoma evansi toward Dromedary Camel Leukocytes

Contact Info

Product

Resources

About