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Elevated cytomegalovirus IgG antibody levels are associated with HIV-1 disease progression and immune activation

Patel, Eshan U.a; Gianella, Sarab; Newell, Kevinc; Tobian, Aaron A.R.d,e,f; Kirkpatrick, Allison R.a; Nalugoda, Fredrickf; Grabowski, Mary K.e,f; Gray, Ronald H.e,f; Serwadda, Davidf,g; Quinn, Thomas C.a,e,h; Redd, Andrew D.a,h; Reynolds, Steven J.a,e,f,h

doi: 10.1097/QAD.0000000000001412
CLINICAL SCIENCE: CONCISE COMMUNICATION
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Objective: To assess the association between cytomegalovirus (CMV) IgG antibody levels, HIV disease progression, and immune activation markers.

Design: A prospective cohort study was conducted among women enrolled in a trial that was designed to determine the effect of acyclovir on HIV disease progression in Rakai, Uganda.

Methods: The primary endpoints were progression to a CD4+ T-cell count less than 250 cells/μl, nontraumatic death, or initiation of antiretroviral therapy (ART). CD4+ T-cell counts, HIV viral load, C-reactive protein (CRP), and soluble CD14 levels were assessed biannually for 24 months. CMV IgG antibodies were measured at baseline among all women and annually among a subset of women who initiated ART.

Results: There were 300 HIV/CMV-coinfected participants who contributed a total of 426.4 person-years with a median follow-up time of 1.81 years. Compared with the lowest CMV IgG tertile group at baseline, the highest CMV IgG tertile group was associated with an increased risk to reach a primary endpoint independent of acyclovir use, age, CD4+ T-cell count, and HIV viral load at baseline [adjusted hazard ratio = 1.59; (95% CI = 1.05–2.39); P = 0.027]. Among pre-ART visits (n = 1200), women in the highest baseline CMV IgG tertile had increasing annual rates of soluble CD14 and CRP levels, which was not observed for the low CMV IgG tertile group. Compared with pre-ART visits, CMV IgG antibody levels were higher post-ART initiation, and concurrent levels remained associated with soluble CD14 and CRP during suppressive ART (n = 88 person-visits).

Conclusion: The magnitude of the immune response to CMV was associated with HIV disease progression and immune activation in sub-Saharan Africa.

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aDivision of Intramural Research, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland

bDepartment of Medicine, University of California San Diego, San Diego, California

cResearch Data and Communication Technologies, Inc., Garrett Park

dDepartment of Pathology, Johns Hopkins School of Medicine

eDepartment of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA

fRakai Health Sciences Program, Kalisizo

gInstitute of Public Health, Makerere University, Kampala, Uganda

hDepartment of Medicine, Johns Hopkins School of Medicine, Baltimore, Maryland, USA.

Correspondence to Steven J. Reynolds, MD, MPH, NIAID/NIH ICER Program, US Embassy, PO Box 7007, Kampala, Uganda. E-mail: sjreynolds@niaid.nih.gov

Received 12 October, 2016

Revised 9 January, 2017

Accepted 12 January, 2017

Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal's Website (http://www.AIDSonline.com).

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Introduction

In resource-rich settings, cytomegalovirus (CMV) coinfection, viremia, subclinical shedding, and viral diversity are associated with an increased risk of progression to AIDS and death among persons living with HIV [1–7]. The humoral immune response to CMV, as measured by CMV-specific IgG antibody, has also been linked to untreated HIV disease progression in MSM [8,9]. Despite use of antiretroviral therapy (ART), CMV coinfection is associated with increased risk of poor non-AIDS-related events [10], and high CMV IgG antibody levels are associated with subclinical cardiovascular disease [11], impaired neurocognitive function [12], and decreased physical function [13]. Interestingly, similar findings have also been made among general populations in the United States and Europe [14–17].

The role of CMV coinfection in HIV pathogenesis is likely bidirectional [18]. HIV-induced immunosuppression might lead to increased CMV reactivation, which in turn can promote HIV replication and immune activation [18,19]. Numerous investigations have suggested that CMV replication continues to drive CD8+ T-cell expansion and inflammation in ART-experienced individuals [20–25]. The cross-sectional evidence is conflicting in untreated and treated HIV-infected individuals, but some studies suggest that CMV IgG antibody levels may also be associated with immune activation markers, such as C-reactive protein (CRP) [13], a general biomarker of systemic inflammation, and soluble CD14 (sCD14) [26] – a biomarker of nonspecific monocyte activation [27].

There are limited data on the role of CMV in chronic HIV disease in sub-Saharan Africa [28–30]. In this region, primary CMV infection predominantly occurs during infancy and is also associated with the development and maintenance of CD8+ T-cell expansion during childhood [31–33]. By adulthood, CMV seroprevalence reaches close to 100% in most populations [29,30], so there is likely a high lifetime risk of reinfection before and during HIV infection. In addition to geographic variability in CMV shedding, CMV IgG antibody dynamics are known to differ by age, behavior, and host-genetics [22,34]. Therefore, we aimed to assess the relationship between CMV IgG antibody levels, and HIV disease progression and immune activation in Rakai, Uganda.

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Methods

Study design

Ugandan women coinfected with HIV-1 and herpes simplex virus type 2 (HSV-2), and a CD4+ T-cell count between 300 and 400 cells/μl, were enrolled in a clinical trial to examine the effect of acyclovir on HIV disease progression over 24 months [35]. Individuals with AIDS-defining illnesses or those receiving ART were excluded. Participants were followed monthly for clinical screenings, drug refill, and adverse event review. Every 6 months, a physical examination was conducted and blood was drawn. Serum was stored at −80 °C. Participants provided written informed consent, and the study was approved by the Uganda Virus Research Institute Science and Ethics Committee, the Uganda National Council for Science and Technology, and the Institutional Review Board of the National Institute of Allergy and Infectious Diseases. The trial was registered with ClinicalTrials.gov (NCT00405821).

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Laboratory testing

CD4+ T-cell counts, HIV viral load, sCD14, and high-sensitivity CRP (hs-CRP) measurements were determined biannually [35,36]. CMV IgG antibody levels were measured at the baseline visit among all women and at the 12-month and 24-month follow-up visits among a subset of women who initiated ART during the study period. CMV IgG antibody levels were measured up to a 1 : 200 dilution (CMV IgG Enzyme Immunoassay Test Kit, Genway Biotech; San Diego, California, USA).

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Statistical analysis

Kaplan–Meier analysis and Cox proportional hazard models were used to assess the association between baseline CMV IgG tertiles and HIV disease progression (composite outcome: nontraumatic death, CD4+ T-cell count ≤250 cells/μl, WHO Stage IV condition, or ART initiation by study clinicians for HIV-related symptoms). Participants were administratively censored at 24 months. The multivariable model included adjustment for study arm and potential baseline confounders: age, CD4+ T-cell count, and HIV viral load. Other baseline covariates did not improve model fit as assessed by the likelihood ratio test and Akaike's information criterion.

In a sensitivity analysis, Cox regression with robust variance estimation was performed among a propensity-matched subcohort (based on the baseline CD4+ T-cell count and HIV viral load) [37,38]; and the model was further adjusted for study arm and age. Greedy one-nearest neighbor 1 : 1 matching on the propensity score was applied to select controls to compare with women in the high CMV IgG tertile group [37].

Linear multilevel modeling with random effects for the intercept and slope were fitted to assess associations between baseline CMV IgG tertiles and annual changes in pre-ART levels of sCD14 and hs-CRP. Among women who initiated ART, random intercept models were used to examine the association of concurrent CMV IgG antibody levels (>median of post-ART visits) and sCD14 and hs-CRP.

Analyses were performed using STATA version 14.1 (StataCorp, College Station, Texas, USA) and R version 3.2 (R Foundation for Statistical Computing, Vienna, Austria).

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Results

Of 311 women enrolled in the trial, 300 had available sera at baseline and all were HIV/HSV-2/CMV coinfected. Lower CD4+ T-cell counts at enrollment were observed among women in the higher baseline CMV IgG tertile groups (P = 0.051). There was a positive association for HIV viral load, sCD14, and hs-CRP with increasing CMV IgG tertiles at baseline (P < 0.05; Table 1).

Table 1

Table 1

All participants contributed a total of 426.4 person-years with a median follow-up time of 1.81 years, and 150 women reached a primary endpoint (including nine nontraumatic deaths). Ten women were lost to follow-up, of which five were in the highest CMV IgG tertile. Compared with women in the low CMV IgG tertile at baseline, women in the highest CMV IgG tertile had a greater cumulative probability of reaching an endpoint (Plog-rank < 0.001; Fig. 1a). The incidence of primary endpoints was 25.9/100 person-years (41/158.4 person-years) for the low CMV IgG tertile, 30.5/100 person-years (44/144.3 person-years) for the middle CMV IgG tertile group, and 52.6/100 person-years (65/123.6 person-years) for the high CMV IgG tertile group. Compared with women in the low CMV IgG tertile at baseline, there was an increased relative hazard of HIV disease progression for women in the high CMV IgG tertile [hazard ratio = 2.21 (95% CI = 1.49–3.27); P < 0.001]. This association was significant despite adjustment for study arm, age, baseline CD4+ T-cell count, and baseline HIV viral load [adjusted hazard ratio = 1.59 (95% CI = 1.05–2.39); P = 0.027; Fig. 1b]. A similar effect was observed when comparing women in the high CMV IgG tertile at baseline with the matched control group [adjusted hazard ratio = 1.61 (95% CI = 1.11–2.33); P = 0.012; Fig. 1b].

Fig. 1

Fig. 1

In an analysis of 1200 person-visits right-censored for ART initiation, baseline CMV IgG antibody levels were associated with annual changes in immune activation markers independent of time-updated CD4+ T-cell count, log10 HIV viral load, and a study arm and time interaction. Women in the low CMV IgG tertile at baseline had annual decreases in sCD14 [β = −158.6 ng/ml/year (SE = 69.3); P = 0.022] during follow-up, but women in the high CMV IgG tertile had an annual increase in sCD14 [β = 199.1 ng/ml/year (SE = 118); P = 0.091]. Women in the high CMV IgG tertile at baseline also had an annual increase in hs-CRP [β = 0.15 log10 mg/l/year (SE = 0.05); P = 0.001]. Women in the low CMV IgG tertile did not have a significant annual change in hs-CRP [β = −0.15 log10 mg/l/year (SE = 0.034); P = 0.671]. The rates of annual change in sCD14 and hs-CRP were significantly different between women in the lowest and highest CMV IgG tertiles at baseline (P < 0.05).

There were 70 women with CMV IgG antibody measured at at least one pre-ART and post-ART visit. On average, post-ART log10 CMV IgG index levels were higher than pre-ART log10 CMV IgG index levels (P = 0.006; Fig. S1, http://links.lww.com/QAD/B42). The median time on ART was 140 days (interquartile range = 112–420). In a visit-specific analysis after ART initiation (n = 95 person-visits), CMV IgG antibody levels above the post-ART median (>0.84 log10 CMV IgG index) were associated with higher levels of sCD14 [β = 421.2 ng/ml (SE = 179.9); P = 0.019] and hs-CRP [β = 0.18 log10 mg/l (SE = 0.08); P = 0.028] independent of study arm, age, time-updated CD4+ T-cell count, and nadir pre-ART CD4+ T-cell count. In a subanalysis of women with virologic suppression (<400 copies/ml; n = 88 person-visits), the adjusted difference in sCD14 and hs-CRP levels by the median level of CMV IgG antibody remained significant (P < 0.05).

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Discussion

In this prospective study, elevated CMV IgG antibody levels at baseline were associated with untreated HIV disease progression in Rakai, Uganda. Elevated CMV IgG antibody levels at baseline were also associated with higher levels and annual increases in pre-ART sCD14 and hs-CRP levels. Subclinical CMV replication during HIV infection (prior to clinical AIDS) is common [25,39] and, in a previous study among women nested in this cohort, we noted that 59% of women had detectable vaginal CMV shedding during the 6-month interval prior to ART initiation [40]. Taken together, these data support the hypothesis that CMV may contribute to systemic immune activation during untreated HIV infection and may be a cofactor in HIV disease progression in sub-Saharan Africa.

The increase in CMV IgG antibody levels after ART may indeed be due to immune reconstitution [41], but also may in part be reflective of a subclinical immune reconstitution inflammatory effect [42]. Among women nested in this cohort, we previously observed an increase in vaginal CMV shedding 2–4 months following ART initiation and that vaginal CMV shedding was associated with elevated vaginal markers of immune activation [40,43]. Similarly, among women on ART for a median of 4–5 months, we noted that elevated post-ART CMV IgG antibody levels were associated with higher plasma immune activation markers. There is considerable variability between studies in precisely which immune activation markers are associated with post-ART CMV IgG levels [11,13,26,44–47], but our findings are consistent with the model suggesting that CMV has a role in driving persistent immune activation during suppressive ART [25]. The durability of these associations requires confirmation during long-term ART use.

The current study has limitations. Due to the high prevalence of CMV among adults in sub-Saharan Africa, it is difficult to directly estimate the effect of CMV coinfection on chronic HIV disease. We therefore measured CMV IgG antibody levels; however, this biomarker cannot be directly interpreted as a surrogate for CMV replication in HIV-infected individuals [48]. As discussed elsewhere [19,22,25], CMV IgG antibody levels may reflect one or a combination of the following: lifetime burden of CMV replication and reinfection, recent CMV reactivation or reinfection, or strength of the host immune response to suppress low-level CMV replication. As we had limited knowledge of other coinfections and did not measure B-cell activation markers or total IgG levels, we cannot exclude the potential for residual confounding, particularly due to aberrant B-cell activation. Notably, however, a previous study demonstrated increases in CMV-specific IgG antibody levels during HIV infection that were not seen for IgG levels specific to other coinfections [49], and weak correlations have been observed between total IgG levels and CMV lysate antibody levels among HIV-infected individuals on ART [12]. It should also be noted that the results from this study may not be generalizable to men or resource-rich settings.

In summary, the magnitude of the CMV-specific humoral immune response was associated with HIV disease progression and immune activation among Ugandan women living with HIV. The role of CMV during chronic HIV infection warrants further investigation in sub-Saharan Africa.

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Acknowledgements

The authors are grateful to the study participants in the trial and to the study staff of the Rakai Health Sciences Program. Support for data management was provided in part by the Office of Cyber Infrastructure and Computational Biology, National Institute of Allergy and Infectious Diseases.

Author contributions: T.C.Q., F.N., D.S., and S.J.R. managed and designed the original trial. A.D.R., S.G., S.J.R., E.U.P., A.A.R.T., T.C.Q., and R.H.G. designed the current study. E.U.P. and A.R.K. performed the laboratory experiments. E.U.P., K.N., and M.K.G. performed the statistical analysis. E.U.P., S.G., A.D.R., and S.J.R. wrote the initial draft of the manuscript. All authors contributed to the overall intellectual content of the manuscript, critically reviewed and edited subsequent drafts, and approved the final version.

The work was supported by the Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health (AI001040), and extramural funding from the National Institutes of Health (AI036214).

Previous presentation: Presented in part at the Conference on Retroviruses and Opportunistic Infections (CROI), Boston, Massachusetts (Abstract ID: 16-740) on 25 February 2016.

Disclaimer: The funder had no role in study design; data collection, analysis, and interpretation; or writing of the manuscript. The content of this study does not necessarily reflect the views or policies of the Department of Health and Human Services. The mention of trade names, commercial products, or organizations does not imply endorsement by the United States Government.

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Conflicts of interest

There are no conflicts of interest.

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References

1. Webster A, Cook D, Emery V, Lee C, Grundy J, Kernoff P, et al. Cytomegalovirus infection and progression towards AIDS in haemophiliacs with human immunodeficiency virus infection. Lancet 1989; 334:63–66.
2. Leach CT, Detels R, Hennessey K, Liu Z, Visscher BR, Dudley JP, et al. A longitudinal study of cytomegalovirus infection in human immunodeficiency virus type 1-seropositive homosexual men: molecular epidemiology and association with disease progression. J Infect Dis 1994; 170:293–298.
3. Sabin CA, Devereux HL, Clewley G, Emery VC, Phillips AN, Loveday C, et al. Cytomegalovirus seropositivity and human immunodeficiency virus type 1 RNA levels in individuals with hemophilia. J Infect Dis 2000; 181:1800–1803.
4. Robain M, Boufassa F, Hubert JB, Dussaix E, Sadeg K, Meyer L. Is cytomegalovirus infection a co-factor in HIV-1 disease progression?. Epidemiol Infect 2000; 125:415–420.
5. Robain M, Boufassa F, Hubert JB, Persoz A, Burgard M, Meyer L, et al. Cytomegalovirus seroconversion as a cofactor for progression to AIDS. AIDS 2001; 15:251–256.
6. Kempen JH, Jabs DA, Wilson LA, Dunn JP, West SK, Tonascia J. Mortality risk for patients with cytomegalovirus retinitis and acquired immune deficiency syndrome. Clin Infect Dis 2003; 37:1365–1373.
7. Deayton JR, Sabin CA, Johnson MA, Emery VC, Wilson P, Griffiths PD. Importance of cytomegalovirus viraemia in risk of disease progression and death in HIV-infected patients receiving highly active antiretroviral therapy. Lancet 2004; 363:2116–2121.
8. Polk BF, Fox R, Brookmeyer R, Kanchanaraksa S, Kaslow R, Visscher B, et al. Predictors of the acquired immunodeficiency syndrome developing in a cohort of seropositive homosexual men. N Engl J Med 1987; 316:61–66.
9. Detels R, Visscher BR, Fahey JL, Sever JL, Gravell M, Madden DL, et al. Predictors of clinical AIDS in young homosexual men in a high-risk area. Int J Epidemiol 1987; 16:271–276.
10. Lichtner M, Cicconi P, Vita S, Cozzi-Lepri A, Galli M, Caputo SL, et al. Cytomegalovirus coinfection is associated with an increased risk of severe non–AIDS-defining events in a large cohort of HIV-infected patients. J Infect Dis 2015; 211:178–186.
11. Parrinello CM, Sinclair E, Landay AL, Lurain N, Sharrett AR, Gange SJ, et al. Cytomegalovirus immunoglobulin G antibody is associated with subclinical carotid artery disease among HIV-infected women. J Infect Dis 2012; 205:1788–1796.
12. Brunt SJ, Cysique LA, Lee S, Burrows S, Brew BJ, Price P. Short communication: do cytomegalovirus antibody levels associate with age-related syndromes in HIV patients stable on antiretroviral therapy?. AIDS Res Hum Retroviruses 2016; 32:567–572.
13. Erlandson KM, Allshouse AA, Rapaport E, Palmer BE, Wilson CC, Weinberg A, et al. Physical function impairment of older, HIV-infected adults is associated with cytomegalovirus immunoglobulin response. AIDS Res Hum Retroviruses 2015; 31:905–912.
14. Roberts ET, Haan MN, Dowd JB, Aiello AE. Cytomegalovirus antibody levels, inflammation, and mortality among elderly Latinos over 9 years of follow-up. Am J Epidemiol 2010; 172:363–371.
15. Simanek AM, Dowd JB, Pawelec G, Melzer D, Dutta A, Aiello AE. Seropositivity to cytomegalovirus, inflammation, all-cause and cardiovascular disease-related mortality in the United States. PLoS One 2011; 6:e16103.
16. Gkrania-Klotsas E, Langenberg C, Sharp SJ, Luben R, Khaw KT, Wareham NJ. Higher immunoglobulin G antibody levels against cytomegalovirus are associated with incident ischemic heart disease in the population-based EPIC-Norfolk cohort. J Infect Dis 2012; 206:1897–1903.
17. Gkrania-Klotsas E, Langenberg C, Sharp SJ, Luben R, Khaw K-T, Wareham NJ. Seropositivity and higher immunoglobulin G antibody levels against cytomegalovirus are associated with mortality in the population-based European prospective investigation of cancer – Norfolk Cohort. Clin Infect Dis 2013; 56:1421–1427.
18. Griffiths PD. CMV as a cofactor enhancing progression of AIDS. J Clin Virol 2006; 35:489–492.
19. Gianella S, Massanella M, Wertheim JO, Smith DM. The sordid affair between human herpesvirus and human immunodeficiency virus. J Infect Dis 2015; 212:845–852.
20. Hunt PW, Martin JN, Sinclair E, Epling L, Teague J, Jacobson MA, et al. Valganciclovir reduces T cell activation in HIV-infected individuals with incomplete CD4+ T cell recovery on antiretroviral therapy. J Infect Dis 2011; 203:1474–1483.
21. Shin LY, Sheth PM, Persad D, Kovacs C, Kain T, Diong C, et al. Impact of CMV therapy with valganciclovir on immune activation and the HIV viral load in semen and blood: an observational clinical study. J Acquir Immune Defic Syndr 2014; 65:251–258.
22. Freeman ML, Lederman MM, Gianella S. Partners in crime: the role of CMV in immune dysregulation and clinical outcome during HIV infection. Curr HIV/AIDS Rep 2016; 13:10–19.
23. Caby F, Guihot A, Lambert-Niclot S, Guiguet M, Boutolleau D, Agher R, et al. Determinants of a low CD4/CD8 ratio in HIV-1-infected individuals despite long-term viral suppression. Clin Infect Dis 2016; 62:1297–1303.
24. Smith DM, Nakazawa M, Freeman ML, Anderson CM, Oliveira MF, Little SJ, et al. Asymptomatic CMV replication during early human immunodeficiency virus (HIV) infection is associated with lower CD4/CD8 ratio during HIV treatment. Clin Infect Dis 2016; 63:1517–1524.
25. Gianella S, Letendre S. Cytomegalovirus and HIV: a dangerous Pas de Deux. J Infect Dis 2016; 214 (suppl 2):S67–S74.
26. Lurain NS, Hanson BA, Hotton AL, Weber KM, Cohen MH, Landay AL. The Association of human cytomegalovirus with biomarkers of inflammation and immune activation in HIV-1-infected women. AIDS Res Hum Retroviruses 2016; 32:134–143.
27. Shive CL, Jiang W, Anthony DD, Lederman MM. Soluble CD14 is a nonspecific marker of monocyte activation. AIDS 2015; 29:1263–1265.
28. Adland E, Klenerman P, Goulder P, Matthews PC. Ongoing burden of disease and mortality from HIV/CMV coinfection in Africa in the antiretroviral therapy era. Front Microbiol 2015; 6:1016.
29. Gronborg HL, Jespersen S, Honge BL, Jensen-Fangel S, Wejse C. Review of cytomegalovirus coinfection in HIV-infected individuals in Africa. Rev Med Virol 2017; 27:e1907.
30. Bates M, Brantsaeter AB. Human cytomegalovirus (CMV) in Africa: a neglected but important pathogen. J Virus Erad 2016; 2:136–142.
31. Miles DJ, van der Sande M, Jeffries D, Kaye S, Ismaili J, Ojuola O, et al. Cytomegalovirus infection in Gambian infants leads to profound CD8 T-cell differentiation. J Virol 2007; 81:5766–5776.
32. Miles DJ, van der Sande M, Jeffries D, Kaye S, Ojuola O, Sanneh M, et al. Maintenance of large subpopulations of differentiated CD8 T-cells two years after cytomegalovirus infection in Gambian infants. PLoS One 2008; 3:e2905.
33. Gantt S, Orem J, Krantz EM, Morrow RA, Selke S, Huang ML, et al. Prospective characterization of the risk factors for transmission and symptoms of primary human herpesvirus infections among Ugandan infants. J Infect Dis 2016; 214:36–44.
34. Goldeck D, Larsen LA, Christiansen L, Christensen K, Hamprecht K, Pawelec G, et al. Genetic influence on the peripheral blood CD4+ T-cell differentiation status in CMV infection. J Gerontol A Biol Sci Med Sci 2016; 71:1537–1543.
35. Reynolds SJ, Makumbi F, Newell K, Kiwanuka N, Ssebbowa P, Mondo G, et al. Effect of daily aciclovir on HIV disease progression in individuals in Rakai, Uganda, co-infected with HIV-1 and herpes simplex virus type 2: a randomised, double-blind placebo-controlled trial. Lancet Infect Dis 2012; 12:441–448.
36. Redd AD, Newell K, Patel EU, Nalugoda F, Ssebbowa P, Kalibbala S, et al. Decreased monocyte activation with daily acyclovir use in HIV-1/HSV-2 coinfected women. Sex Transm Infect 2015; 91:485–488.
37. Austin PC. The performance of different propensity score methods for estimating marginal hazard ratios. Stat Med 2013; 32:2837–2849.
38. Austin PC. The use of propensity score methods with survival or time-to-event outcomes: reporting measures of effect similar to those used in randomized experiments. Stat Med 2014; 33:1242–1258.
39. Morris SR, Zhao M, Smith DR, Vargas MV, Little SJ, Gianella S. Longitudinal viral dynamics in semen during early HIV infection. Clin Infect Dis 2016; [Epub ahead of print] doi: 10.1093/cid/ciw784.
40. Gianella S, Redd AD, Grabowski MK, Tobian AA, Serwadda D, Newell K, et al. Vaginal cytomegalovirus shedding before and after initiation of antiretroviral therapy in Rakai, Uganda. J Infect Dis 2015; 212:899–903.
41. Deayton JR, Sabin CA, Britt WB, Jones IM, Wilson P, Johnson MA, et al. Rapid reconstitution of humoral immunity against cytomegalovirus but not HIV following highly active antiretroviral therapy. AIDS 2002; 16:2129–2135.
42. Stone SF, Price P, Tay-Kearney ML, French MA. Cytomegalovirus (CMV) retinitis immune restoration disease occurs during highly active antiretroviral therapy-induced restoration of CMV-specific immune responses within a predominant Th2 cytokine environment. J Infect Dis 2002; 185:1813–1817.
43. Nason MC, Patel EU, Kirkpatrick AR, Prodger JL, Shahabi K, Tobian AA, et al. Immunological signaling during herpes simplex virus-2 and cytomegalovirus vaginal shedding after initiation of antiretroviral treatment. Open Forum Infect Dis 2016; 3:ofw073.
44. Brunt SJ, Lee S, D’Orsogna L, Bundell C, Burrows S, Price P. The use of humoral responses as a marker of CMV burden in HIV patients on ART requires consideration of T-cell recovery and persistent B-cell activation. Dis Markers 2014; 2014:947432.
45. Affandi JS, Montgomery J, Brunt SJ, Nolan D, Price P. The immunological footprint of CMV in HIV-1 patients stable on long-term ART. Immun Ageing 2015; 12:14.
46. Hodowanec A, Williams B, Hanson B, Livak B, Keating S, Lurain N, et al. Soluble CD163 but not soluble CD14 is associated with cytomegalovirus immunoglobulin G antibody levels in virologically suppressed HIV+ individuals. J Acquir Immune Defic Syndr 2015; 70:e171–e174.
47. Brunt SJ, Cysique LA, Lee S, Burrows S, Brew BJ, Price P. Short communication: do cytomegalovirus antibody levels associate with age-related syndromes in HIV patients stable on antiretroviral therapy?. AIDS Res Hum Retroviruses 2016; 32:567–572.
48. Gianella S, Morris SR, Tatro E, Vargas MV, Haubrich RH, Daar ES, et al. Virologic correlates of anti-CMV IgG levels in HIV-1 infected men. J Infect Dis 2014; 209:452–456.
49. Lennette ET, Busch MP, Hecht FM, Levy JA. Potential herpesvirus interaction during HIV type 1 primary infection. AIDS Res Hum Retroviruses 2005; 21:869–875.
Keywords:

cytomegalovirus; HIV disease progression; humoral immune response; immune activation; inflammation

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