Cytokine Gene Expression Alterations in Human Macrophages Infected by Leishmania major
Khodaberdi Kalavi1,2, Ogholniaz Jorjani2, Mohammad Ali Faghihi3,4
1Department of Molecular Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran.
Objective:
Leishmaniasis is caused by members of the Leishmania species and constitute a group of infective diseases that range from cutaneous lesions to lethal visceral forms. In infected persons, macrophages recognize and eliminate the parasites via phagocytosis. In order to change a hostile environment into an environment adequate for survival and reproduction, the engulfed Leishmania species needs to modulate the function of its host macrophage. The expression patterns of cytokine genes such as interleukin-12 (IL-12), tumour necrosis factor-alpha (TNF-α), IL-1, and interferon-gamma (IFNγ) represent the immune response. In this study, we employed an RNA-seq approach for human monocyte-derived macrophages infected with Leishmania major (L. major) to decipher cytokine gene expression alterations in host macrophages.
Materials And Methods:
In this descriptive study, human monocytes were isolated by magnetic activated cell sorting (MACS) and cultured in the presence of monocyte colony stimulating factor (M-CSF) to obtain the macrophages. Monocyte-derived macrophages were then co-cultured with metacyclic promastigotes of L. major for 4 hours. RNA isolation was performed using TRIzol reagent. RNA sequencing was performed using the Illumina sequencing platforms. Gene expression analysis was performed using a Bioconductor DESeq2 package.
Results:
Our data revealed significant changes in immune response gene expressions in macrophages infected with L. major, with an up-regulation of cytokines and mostly down-regulation of their receptors.
Conclusion:
The obtained data could shed more light on the biology of L. major and how the host cell responds to leishmaniasis.
Insights
Leishmania major infection alters macrophage immune responses. RNA sequencing revealed significant changes in cytokine gene expression, with increased cytokines and decreased receptors in infected host cells.
Area of Science:
- Immunology
- Molecular Biology
- Parasitology
Background:
- Leishmaniasis is a parasitic disease caused by Leishmania species, presenting diverse clinical forms.
- Macrophages are key host cells involved in Leishmania infection, attempting to eliminate parasites via phagocytosis.
- Leishmania parasites modulate host macrophage function to ensure survival and reproduction within the host.
Purpose of the Study:
- To investigate cytokine gene expression alterations in human macrophages upon infection with Leishmania major.
- To utilize RNA sequencing to decipher the host immune response at the gene expression level.
Main Methods:
- Human monocytes were isolated and differentiated into macrophages.
- Macrophages were co-cultured with Leishmania major promastigotes.
- RNA sequencing (Illumina) and differential gene expression analysis (DESeq2) were performed.
Main Results:
- Significant alterations in immune response gene expression were observed in Leishmania major-infected macrophages.
- Upregulation of cytokine genes was a prominent finding.
- Downregulation of cytokine receptors was also observed.
Conclusions:
- The study provides insights into the host cell response during Leishmania major infection.
- Understanding these gene expression changes can illuminate Leishmania biology and host-parasite interactions.
