Search Ethics Committee (ethical approval number 2649/ 001) in compliance with the HelsinkiSearch Ethics Committee

Search Ethics Committee (ethical approval number 2649/ 001) in compliance with the Helsinki
Search Ethics Committee (ethical approval number 2649/ 001) in compliance with the Helsinki Declaration.Competing interests The authors declare that they have no competing interests. Authors’ contributions BT carried out the studies, participated in their design, analyzed the data and drafted the manuscript. MAC helped design experiments and analyze the data. DP conceived the study, participated in its design and helped draft the manuscript. CJ conceived the study, participated in its design, helped analyze data and helped draft the manuscript. All authors read and approved the final manuscript. Acknowledgements We thank members of the Pillay and Jolly laboratories for general assistance. This work was supported by a Commonwealth Scholarship to BT:, and a UK Medical Research Council Career Development Fellowship (G0800312) to CJ. We also acknowledge support from the European Union funded FP7 CHAIN program (HEALTH-2007 223131), the NIHR UCL Hospitals Biomedical Research Centre and the UCL/MRC Centre for Medical Molecular Virology.Titanji et al. Retrovirology 2013, 10:161 http://www.retrovirology.com/content/10/1/Page 11 of21. Jolly C: Cell-to-cell transmission of retroviruses: innate immunity and interferon-induced restriction factors. Virology 2011, 411(2):251?59. 22. Richardson MW, Carroll RG, Stremlau M, Korokhov N, Humeau LM, Silvestri PubMed ID:http://www.ncbi.nlm.nih.gov/pubmed/25432023 G, Sodroski J, Riley JL: Mode of transmission affects the sensitivity of human immunodeficiency virus type 1 to restriction by rhesus Avermectin B1a biological activity TRIM5alpha. J Virol 2008, 82(22):11117?1128. 23. Permanyer M, PubMed ID:https://www.ncbi.nlm.nih.gov/pubmed/28878015 Ballana E, Ruiz A, Badia R, Riveira-Munoz E, Gonzalo E, Clotet B, Este JA: Antiretroviral agents effectively block HIV replication after cell-to-cell transfer. J Virol 2012, 86(16):8773?780. 24. Kempf DJ, Marsh KC, Kumar G, Rodrigues AD, Denissen JF, McDonald E, Kukulka MJ, Hsu A, Granneman GR, Baroldi PA, et al: Pharmacokinetic enhancement of inhibitors of the human immunodeficiency virus protease by coadministration with ritonavir. J Antimicrob Chemother 1997, 41(3):654?60. 25. De Meyer S, Azijn H, Surleraux D, Jochmans D, Tahri A, Pauwels R, Wigerinck P, de Bethune MP: TMC114, a novel human immunodeficiency virus type 1 protease inhibitor active against protease inhibitor-resistant viruses, including a broad range of clinical isolates. J Antimicrob Chemother 2005, 49(6):2314?321. 26. Bierman WF, van Agtmael MA, Nijhuis M, Danner SA, Boucher CA: HIV monotherapy with ritonavir-boosted protease inhibitors: a systematic review. AIDS 2009, 23(3):279?91. 27. Perez-Valero I, Arribas JR: Protease inhibitor monotherapy. Curr Opinion Infect Dis 2011, 24(1):7?1. 28. Gupta RK, Jordan MR, Sultan BJ, Hill A, Davis DH, Gregson J, Sawyer AW, Hamers RL, Ndembi N, Pillay D, et al: Global trends in antiretroviral resistance in treatment-naive individuals with HIV after rollout of antiretroviral treatment in resource-limited settings: a global collaborative study and meta-regression analysis. Lancet 2012, 380(9849):1250?258. 29. WHO: HIV Drug Resistance Report. Geneva, Switzerland: WHO HIV/AIDS Prog, July 2012; 2012. http://www.who.int/hiv/pub/drugresistance/report2012/en/ accessed November 2013. 30. Rabi SA, Laird GM, Durand CM, Laskey S, Shan L, Bailey JR, Chioma S, Moore RD, Siliciano RF: Multi-step inhibition explains HIV-1 protease inhibitor pharmacodynamics and resistance. J Clin Inv 2013, 123(9):3848?860. 31. Jolly C, Booth NJ, Neil SJ: Cell-cell spread of human immunodeficiency virus type 1 overcomes tetherin/BST-2-med.