Ral therapy. Cotton was infected with a highly divergent SIVcpzPts strain
Ral therapy. Cotton was infected with a highly divergent SIVcpzPts strain (ANT) that differs from HIV1 in up to 48 of Env protein sequences. b Plasma virus loads (copies/ml) in Cotton over a 17year time span (sample dates are indicated). SIVcpzANT viral loads were determined using a sensitive vali dated RTqPCR method that detects both SIVcpz and HIV1 infections [21]. A dashed red line indicates the onset of SB 202190 site Antiretroviral therapy (January 19, 2015). c Nucleotide sequence alignment of HIV1 clade B and SIVcpzPts strains in the long terminal repeat (LTR) region (SIVcpzANT LTR sequences are not available). Sequences are compared to HIV1/IIIb, with dots indicating sequence identity and dashes indicating gaps introduced for optimal alignment. LTR sequences from Cotton are much more closely related to SIVcpzPts than to HIV1 strains, indicating that he is solely infected with SIVcpzANTcopies/ml in 2001 to 1,441,000 RNA copies/ml in 2012 (Fig. 1b), significantly higher than previously reported for some of these same time points [17]. Since our RT-qPCR approach was rigorously validated using both human and chimpanzee plasma samples of known viral content, the previous results likely represent an underestimation of Cotton’s viral loads. To exclude a low-level HIV-1 infection, we sequenced the 121 base pair LTR region used for RT-qPCR analysis PubMed ID:https://www.ncbi.nlm.nih.gov/pubmed/25609842 (Fig. 1c). Amplicons were prepared for MiSeq sequencing (Nextera DNA Library Prep Kit, Illumina, La Jolla, CA, USA) and the resulting reads were mapped to HIV-1 and SIVcpzPts reference sequences, since LTR sequences of the original SIVcpzANT isolate are not available [22]. This approach yielded 11,679 paired-end reads, all of which were much more closely related to SIVcpzPts than to HIV-1 sequences, including HIV-1/IIIb (Fig. 1c), indicating that Cotton is solely infected with SIVcpzANT.Antiretroviral therapy of SIVcpzinduced clinical immunodeficiency Given Cotton’s laboratory and clinical findings, antiretroviral therapy (ART) was initiated on January 19, 2015, using a combination of the nucleoside reverse transcriptase inhibitors tenofovir disoproxil fumarate (TDF) and emtricitabine (FTC), and the integrase strand transfer inhibitor dolutegravir (DTG) at daily doses of 300, 200 and 50 mg, respectively. This regimen was selected because it is recommended for HIV-1 infected adults [23] and potently inhibits both HIV-1 and HIV-2 in humans [24?7]. It also PubMed ID:http://www.ncbi.nlm.nih.gov/pubmed/27488460 potently inhibits SIVmac, a virus even more distantly related to HIV-1 than SIVcpzANT, in experimentally infected rhesus macaques [28]. As shown in Fig. 1b, this regimen reduced SIVcpzANT viremia in Cotton to undetectable levels as determined by RT-qPCR (less than 200 copies/ml) at the first blood analysis 7 weeks after initiation of therapy (3/12/15).1/17/Barbian et al. Retrovirology (2017) 14:Page 4 ofThe treatment refractory anal fistulas healed completely within 4 weeks of onset of therapy, and CD4 T cell counts increased from 220 to 509 cells/l after 2 years of treatment (1/17/17), demonstrating the effectiveness of this regimen in achieving clinical improvement. Cotton received ART daily by oral administration of crushed tablets dissolved in diluted fruit syrup, but caretakers noticed that he did not always ingest his medication completely. We thus continued to monitor his virus load in blood samples obtained during his bi-annual medical evaluations. Indeed, nine months following initiation of therapy (9/25/15), virus was again detectable (4760 RNA.
