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+. Lineage, (C) SIVagm-infected SupT1 cells and free virions were used to stimulate 474 AGM PBMCs (n = 5) (D) SIVagm or AT2-inactivated SIVagm was used to stimulate AGM PBMCs 475 (n = 8) Individual symbols represent distinct animals. Median and interquartile range are 476 shown. Vertical dashes separate the different viral preparations used to test pDC sensing, p.477

*. Wilcoxon, Median values are represented by a horizontal line (blue and red for SIVagm and HIV/SIVmac, 482 respectively). * Wilcoxon, p.483

. Sivagm, Tox = cytotoxic in 18 hour culture. (C) AGM 484 PBMC (n=10) were stimulated with medium (grey circle, 15, 150 or 1500 ng/mL p27 SIVmac251 485 (red square) or SIVmac239 (blue triangle) for 18 hours after which viability was measured

. Mann-whitney, 510 Symbols represent individual animals and the line and bars represent the median and 511 interquartile range