Gene expression of host restriction factors in HIV‐1 infected monocyte‐derived macrophages

Abstract

The Human Immunodeficiency Virus 1 (HIV‐1) replication cycle has been one of the world's most significant research topics up to date. Although HIV‐1 is capable to infect CD4+ T cells, such as lymphocytes and monocytes, previous studies had demonstrated that cells can inhibit this infection using host restriction factors. Restriction factors, like SAMHD1 and SLFN11, have been shown to interfere with many stages of the retroviral life cycle. Macrophages are able to resist HIV‐1 infection much better than CD4+ T cells. A possible explanation for this is that some of the host restriction factors (SAMHD1 and SLFN11) are strongly expressed in cells of the myeloid lineage. Therefore, the overall aim of this project is to determine gene and protein expression changes of host restriction factors SAMHD1 and SLFN11 between undifferentiated and differentiated monocytes. A monocyte cell line (THP‐1) was chemically differentiated to macrophages using phorbol 12‐myristate 13‐acetate (PMA) and infected with a macrophage‐tropic HIV‐1 strain. Total proteins and RNA from undifferentiated and differentiated monocytes were isolated. Relative SAMHD1 and SLFN11 mRNA expression was quantified by RT‐qPCR and the mean change in expression was calculated using the comparative Ct method using GAPDH as a housekeeping gene. To assess differences in protein expression, western blot analysis was performed using anti‐SAMHD1 and anti‐SLFN11 antibodies. Intriguingly, mRNA expression of SAMHD1 was higher in undifferentiated monocytes when compared to monocyte‐derived macrophages (MDM). Hence, the gene expression of SLFN11 was lower in MDM than undifferentiated monocytes. Assessment of protein expression changes is currently ongoing. Our data shows that differentiation of monocytes to macrophages can alter the expression of these restriction factors. Consequently, these changes might affect the cell permissiveness to infection which may lead to involving restriction factors in anti‐retroviral therapies.Support or Funding InformationThis work was supported by NIGMS‐NIH grants: 5SC3GM088032‐08 (MH), UPR‐Ponce Research Initiative for Scientific Enhancement (R25GM096955). The author also acknowledges the support from the Molecular and Genomics Core (MAGIC) at Ponce Health Sciences University (NIMHD Grant MD007579).This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.