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Development and characterization of a human microglia cell model of HIV-1 infection

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Abstract

Microglia cells are the major reservoir of HIV-1 (HIV) within the CNS. However, current models using transformed cell lines are not representative of primary microglia and fetal brain samples for isolation of primary human microglia (HMG) are increasingly difficult to obtain. Here, we describe a monocyte-derived microglia (MMG) cell model of HIV infection that recapitulates infection of primary HMG. CD14+ cells isolated from healthy donors were cultured with M-CSF, beta-nerve growth factor, GM-CSF, and CCL2, and compared to HMG. MMG and HMG cells were infected with HIV and viral replication was detected by p24 antigen. Both MMG and HMG cells were found to acquire spindle shape with few branched or unbranched processes at their ends during the second week in culture and both were found to be CD11b+/ CD11c+/ CD14+/ CD45+/ CD195+/ HLADRlow/ CD86low/ CD80+. Whereas hT-Hμglia and HMC3 transformed cell lines are deficient in human microglia signature genes (C1Q, GAS6, GPR34, MERTK, PROS1, and P2RY12), MMG cells expressed all of these genes. Additionally, MMG expressed all the microglia signature miRNA (miR-99a, miR125b-5p, and miR-342-3p). Both MMG and HMG produced ROS and phagocytosed labeled zymosan particles upon PMA stimulation. MMG and HMG infected with HIV produced equivalent levels of HIV p24 antigen in culture supernatants for 30 days post-infection. Thus, we have developed and characterized a microglia cell model of HIV infection derived from primary monocytes that recapitulates the phenotypic and molecular properties of HMG, is superior to transformed cell lines, and has similar HIV replication kinetics to HMG.

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Acknowledgments

This research was supported in part by 1R01 NS077874 and 1R01 NS077874 from the National Institute of Neurological Disorders and Stroke and the International Maternal Perinatal Adolescent AIDS Clinical Trials (IMPAACT) Network. Overall support for the International Maternal Pediatric Adolescent AIDS Clinical Trials Group (IMPAACT) was provided by NIAID (U01 AI068632) and the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD; contract number N01-DK-9-001/HHSN267200800001C). We thank Terrance Robinson, Rodney Trout, and Byungho Wang for technical assistance and Gang Zhang for isolation and culture of primary human microglia.

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  1. Department of Pediatrics, Division of Infectious Diseases, University of California San Diego, La Jolla, CA, 92093-0672, USA

    Pratima Rawat & Stephen A. Spector

  2. Rady Children’s Hospital, San Diego, CA, 92123, USA

    Stephen A. Spector

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  1. Pratima Rawat
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Correspondence to Stephen A. Spector.

Ethics declarations

HIV seronegative donors were enrolled for venous blood draw using a protocol that was reviewed and approved by the Human Research Protection Program of the University of California, San Diego, in accordance with the requirements of the Code of Federal Regulations on the Protection of Human subjects (45 CFR 46 and 21 CFR 50 and 56). Written informed consent was obtained from all blood donors prior to their participation. Normal human fetal brain tissue was obtained from the University of Washington and approved by the Human Research Protection Program of the University of California, San Diego (Project # 150172XX), in accordance with the requirements of the Code of Federal Regulations on the Protection of Human subjects (45 CFR§46.102 (f)).

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The authors declare that they have no conflict of interest.

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Rawat, P., Spector, S.A. Development and characterization of a human microglia cell model of HIV-1 infection. J. Neurovirol. 23, 33–46 (2017). https://doi.org/10.1007/s13365-016-0472-1

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