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Abstract: FR-PO819

Tar Sequence (Double-Stranded-RNA)-PKR Activation Mediated Podocyte Injury with HIV-1 Infection

Session Information

Category: Glomerular Diseases

  • 1202 Glomerular Diseases: Immunology and Inflammation

Authors

  • Okamoto, Koji, NIDDK, National Institutes of Health, Bethesda, United States
  • Yoshida, Teruhiko, NIDDK, National Institutes of Health, Bethesda, Maryland, United States
  • Miyazaki, Mariko, Tohoku University Hospital, Sendai, Japan
  • Kopp, Jeffrey B., NIDDK, National Institutes of Health, Bethesda, Maryland, United States
Background

Podocyte damage by Human Immunodeficiency Virus (HIV-1) is critical to the pathogenesis of HIV-1 associated nephropathy (HIVAN). There is an evidence that viral RNA and proteins detected in podocytes, but there is no productive infection. While APOL1 risk genotypes for FSGS is also the risk for HIVAN. We reported that activated PKR (interferon-induced double-stranded RNA-activated protein kinase) by double-stranded-RNA (dsRNA) of APOL1 mediates APOL1 nephropathy (Figure). HIV-1 also has dsRNA structures called tar sequence. Our hypothesis is that activated PKR by tar sequence could be cause of podocute injury in HIVAN.

Methods

We prepared virus stocks were prepared by transfecting 293T cells with lymphocyte tropic pNL4-3 and Macrophage-Tropic pNL(AD8) tittered by p24 ELISA assay. Differentiated conditionally immortalized human podocytes were cultured a 6 well plate and infected with virus (p24 100 ng/6-well).

Results

After 6 hours incubation, activated PKR signal was observed and prominent in podocyte cell line from APOL1 risk genotype with pNL(AD8). WT-1 signal was decreased in Podocyte cell line after 96 hours incubation. Virus RNA (rev, vpu, env, and nef) was detected in podocytes by RNA sequence analysis, however, there is no productive infection. Next we generate tar sequence mutated virus (Figure). Activated PKR signal was not observed with mutated tar sequence. Specific PKR inhibitor demonstrated that PKR inhibitor reduced activated PKR and ameliorate WT-1 decline.

Conclusion

HIV-1 direct infection on podocyte cell line providing mechanism by which tar sequence of HIV-1 contributes to cell injury via PKR. Targeting tar sequence - PKR opens novel therapeutic approaches to treating HIVAN.

Funding

  • NIDDK Support