Cytomegalovirus infection in the era of HAART: fewer reactivations and more immunity

Anti-cytomegalovirus preemptive therapy to prevent cytomegalovirus disease in HIV-infected patients: a systematic review

BACKGROUND

HIV patients are at higher risk of contracting and developing into an asymptomatic form of CMV infection. This review aimed to evaluate the efficacy and safety of preemptive therapy for preventing CMV disease in HIV patients.

METHODS

The electronic search was conducted in MEDLINE/PubMed and CENTRAL from inception until 9 September 2022. Studies were included if they assessed the efficacy or safety of anti-CMV preemptive therapy compared to placebo or no therapy. Risk of bias were assessed using the Cochrane Risk of Bias tool for randomized trials version 2 or the Cochrane Collaboration Risk of Bias in Non-randomized Studies of Interventions. The random-effects model was used to calculate effect sizes.

RESULTS

We identified six RCTs (2135 participants) and four observational studies (395 participants), with five RCTs were performed before highly active antiretroviral therapy (HAART) era. Preemptive therapy did not reduce the incidence of CMV disease (RR 0.84, 95% CI: 0.59-1.18), yet reduced the RR of all-cause mortality rate by 26% (RR 0.85, 95% CI: 0.74-0.97) with a low quality of evidence. The incidence of neutropenia as an adverse event increased significantly (RR 2.47, 95% CI: 1.12-5.45) with moderate quality of evidence.

CONCLUSIONS

With the advent of HAART, a limited number of studies have been performed to explore anti-CMV preemptive therapy due to the improved outcomes of HIV patients with CMV viremia. Therefore, optimal HAART should take precedence over anti-CMV preemptive therapy. The protocol for this review was registered in the Prospective Register of Systematic Reviews (CRD42020145765).

Mycophenolate Mofetil-Induced Cytomegalovirus Colitis in a Patient With Polymyositis

As the rate of autoimmune conditions and cancers is increasing in the United States, a larger number of patients are being managed with immunosuppressive medications. Diarrhea is a common problem in immunocompromised patients. A feared complication of immunosuppression is infection with opportunistic pathogens. Cytomegalovirus is an opportunistic infection that can cause infection in a variety of different organ systems, including affecting the gastrointestinal system. Severe infection is most commonly seen as a complication of acquired immunodeficiency syndrome (AIDS), organ transplant, hematological malignancy, or cancer therapy. This case report describes a case of cytomegalovirus colitis in an immunosuppressed patient following mycophenolate mofetil (CellCept) therapy.

Cytomegalovirus viremia as a risk factor for mortality in HIV-associated cryptococcal and tuberculous meningitis

OBJECTIVES

CMV viremia is associated with increased mortality in persons with HIV. We previously demonstrated that CMV viremia was a risk factor for 10-week mortality in antiretroviral therapy (ART)-naïve persons with cryptococcal meningitis. We investigated whether similar observations existed over a broader cohort of patients with HIV-associated meningitis at 18 weeks.

METHODS

We prospectively enrolled Ugandans with cryptococcal or TB meningitis into clinical trials in 2015-2019. We quantified CMV DNA concentrations from stored baseline plasma or serum samples from 340 participants. We compared 18-week survival between those with and without CMV viremia.

RESULTS

We included 308 persons with cryptococcal meningitis and 32 with TB meningitis, of whom 121 (36%) had detectable CMV DNA. Baseline CD4+ T-cell counts (14 vs. 24 cells/µl; P = 0.07) and antiretroviral exposure (47% vs. 45%; P = 0.68) did not differ between persons with and without CMV viremia. The 18-week mortality was 50% (61/121) in those with CMV viremia versus 34% (74/219) in those without (P = 0.003). Detectable CMV viremia (adjusted hazard ratio [aHR] 1.60; 95% confidence interval [CI] 1.13-2.25; P = 0.008) and greater viral load (aHR 1.22 per log10 IU/ml increase; 95% CI 1.09-1.35; P <0.001) were positively associated with all-cause mortality through 18 weeks.

CONCLUSION

CMV viremia at baseline was associated with a higher risk of death at 18 weeks among persons with HIV-associated cryptococcal or TB meningitis, and the risk increased as the CMV viral load increased. Further investigation is warranted to determine whether CMV is a modifiable risk contributing to deaths in HIV-associated meningitis or is a biomarker of immune dysfunction.

Cytomegalovirus cell tropism and clinicopathological characteristics in gastrointestinal tract of patients with HIV/AIDS

BACKGROUND

Cytomegalovirus (CMV) has been recognized as one of the frequently occurring opportunistic infections (OIs) reported in the patients having human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS). In addition, it has been identified as the factor leading to gastrointestinal (GI) tract disorder among HIV/AIDS population. CMV exhibits broad cell tropism in different organs. This study evaluated the CMV cell tropism and clinicopathological characteristics of CMV infection in the different GI regions in HIV/AIDS cases.

METHODS

Using nucleic acid in situ hybridization (ISH), CMV was detected in the gastrointestinal mucosal biopsy samples. The paraffin-embedded samples were stained with hematoxylin and eosin (HE) and immunohistochemistry (IHC), respectively.

RESULTS

A total of 32 HIV/AIDS patients were enrolled in this study. Fourteen of these patients underwent gastroscopy, while the remaining eighteen received colonoscopy. CMV-infected cells were observed at 46 GI sites. Among them, the colon was the region with the highest susceptibility to GI CMV infection (n = 12, 26.1%). The CMV giant cell inclusion bodies were detected in epithelial cells and mesenchymal cells, including histiocytes, smooth muscle cells, fibroblasts, and endothelial cells. In the duodenum, there were markedly more positive epithelial cells than mesenchymal cells (p = 0.033). In contrast, in the esophagus (p = 0.030), cardia (p = 0.003), rectum (p = 0.019), colon (p < 0.001), and cecum (p < 0.001), there were notably less positive epithelial cells than mesenchymal cells. The expression levels of PDGFRα and Nrp2 in the mesenchymal cells were higher than the epithelial cells in cardia, cecum, colon, sigmoid, and rectum, especially in the areas with ulcers. However, Nrp2 in the epithelial cells was higher than that in the duodenum. Moreover, the positive CMV DNA in peripheral blood was related to the CMV-positive cell count, as well as the ulceration in GI tract (p = 0.035 and 0.036, respectively).

CONCLUSIONS

The colon has been identified as the GI site with the highest susceptibility to CMV infection. There are different CMV-infected cells in the different sites of the GI that relate to the expression level of PDGFRα and Nrp2. CMV DNA positive in the blood is related to the positive CMV cell count, as well as ulceration in the GI tract.

Systemic cytomegalovirus masquerading as a colorectal mass in a patient with undiagnosed HIV/AIDS

Introduction

Cytomegalovirus (CMV) infection is common among patients with human immunodeficiency virus (HIV) infection. Gastrointestinal (GI) involvement with tumor like lesion is a rare presentation. Our patient presented with rectal pain and findings concerning for malignancy. Subsequently our patient was diagnosed with acquired immunodeficiency syndrome (AIDS), CMV viremia and CMV proctitis.

Case

A 37-year-old man who reported having sex with men presented with severe proctalgia and hematochezia. Imaging showed irregular rectal wall thickening concerning for malignancy. Sigmoidoscopy revealed a circumferential necrotic lesion suspicious for malignancy. Surprisingly, biopsy showed a cytopathic effect compatible with CMV infection. In addition to testing positive for CMV, patient was newly diagnosed with HIV/AIDS, hepatitis C, syphilis, and gonorrhea. CMV infection was treated with ganciclovir, which resulted in a significant response. Ganciclovir was later replaced with valganciclovir. Valganciclovir was continued and antiretroviral therapy (ART) was started as an outpatient and with resolution of symptoms.

Discussion

CMV infection is one of the most common opportunistic infections among patients with HIV infection. Several cases of CMV colitis were reported among immunocompromised patients. Our patient’s presenting symptoms and direct visualization of rectal lesion were not only deceptive but also unique. As what looked like a rectal malignancy was later diagnosed as tissue invasive CMV by biopsy. Invasive CMV infection should be managed with ganciclovir.

Conclusion

GI CMV as the initial presentation of HIV is rare. Moreover, CMV proctitis can masquerade as a rectal cancer and clinicians should be aware of this rare presentation of CMV.

Encephalitis Due to Co-Infection with Cytomegalovirus and Herpes Simplex Virus Type 2 in a Patient with Acquired Immunodeficiency Syndrome

BACKGROUND Opportunistic infections are commonly seen in immunocompromised patients. Here, we present an interesting case of a patient with poorly controlled human immunodeficiency virus (HIV) infection who presented with multiple opportunistic infections. CASE REPORT A 44-year-old woman with medical history of HIV infection (CD4 <20 cells/µl, viral load 172 996 copies/ml), presented with symptoms of headache for 2 days and changes in mentation. She was recently treated for pulmonary mycobacterium avium complex infection. Her physical examination revealed normal breath sounds and her abdominal examination was unremarkable. She did not have any focal neurological deficits, nuchal rigidity, or papilledema on examination. Computed tomography (CT) head was negative for any acute lesions. She was empirically started on vancomycin and piperacillin-tazobactam. Due to persistent symptoms, a lumbar puncture was performed, which revealed elevated total proteins in CSF, and a viral polymerase chain reaction test was positive for herpes simplex virus type 2 (HSV-2) and cytomegalovirus (CMV). Magnetic resonance imaging of the brain showed mild enhancement of the ventricular lining. She was treated with acyclovir, which was later changed to ganciclovir, with resulting clinical improvement. The patient had clinical improvement and was discharged home. CONCLUSIONS Multiple opportunistic co-infections should be considered in patients with poorly controlled HIV infection.

Low frequency of cytomegalovirus (CMV) disease despite high prevalence of CMV viraemia in patients with advanced HIV infection: a clinical and immunological 48-week follow-up study

OBJECTIVES

The aim of the study was to investigate the dynamics of cytomegalovirus (CMV) replication and CMV-specific immune response recovery after antiretroviral treatment (ART) initiation in patients with advanced HIV infection.

METHODS

A prospective observational study of patients with HIV infection and CD4 counts of < 100 cells/µL was carried out (September 2015 to July 2018). HIV viral load (VL), CD4 count and CMV VL were determined by quantitative polymerase chain reaction (PCR) at baseline and at 4, 12, 24 and 48 weeks, and CMV-specific immune response was determined by QuantiFERON-CMV assay at baseline and 48 weeks. All patients were started on ART but only those with CMV end-organ disease (EOD) received anti-CMV treatment.

RESULTS

Fifty-three patients with a median age of 43.6 [interquartile range (IQR) 36.7-52.4] years were included in the study. At baseline, the median CD4 count was 30 cells/µL (IQR 20-60 cells/µL) and the median HIV VL was 462 000 HIV-1 RNA copies/mL (IQR 186 000-1 300 000 copies/mL). At baseline, 32% patients had detectable CMV viraemia but none had detectable CMV viraemia at 48 weeks. Only one of 53 (1.9%) patients developed EOD during follow-up. Seven (13.2%) patients were lost to follow-up and six (11.3%) died; none of the deaths was related to CMV. Similar percentages of patients had a CMV-specific immune response at baseline (71.7%) and at 48 weeks (70.0%). The magnitude of this response tended to increase over time [median 1.63 (IQR 0.15-5.77) IU/mL at baseline vs. median 2.5 (IQR 0.1-8.325) IU/mL at 48 weeks; P = 0.11]. We did not find any risk factors associated with 48-week mortality.

CONCLUSIONS

Although the prevalence of CMV viraemia in patients with advanced HIV infection remains high, achieving a good immunological recovery through ART is enough to suppress CMV viraemia, without an increased risk of CMV EOD. The prevalence of a CMV-specific immune response was high and endured over time.

Refractory pharyngeal ulceration due to cytomegalovirus in a patient with HIV infection: a case report and literature review

BACKGROUND

Cytomegalovirus (CMV) is an important pathogen among immunocompromised hosts. Typically, CMV in human immunodeficiency virus (HIV) infection causes diseases of the retina, digestive tract, lungs and liver, but there are few cases of CMV infection of the pharynx and larynx.

CASE PRESENTATION

A 57-year-old man with HIV infection was admitted because of pharyngeal pain. Before and after admission, pharyngeal biopsies guided by laryngeal endoscopy were performed four times, but pathological examination showed nonspecific inflammation, and the cause of pharyngeal ulceration was unclear. Additionally, the ulceration deteriorated after initiation of retroviral therapy. Laryngomicrosurgery was conducted under general anesthesia to remove tissue, and pathological diagnosis confirmed CMV infection. Pathological features included enlargement of the cytoplasm and nucleus in infected cells, and intranuclear bodies called owl's eye inclusions. Ganciclovir dramatically improved the symptoms and laryngoscopic findings.

CONCLUSIONS

This case was diagnosed as pharyngitis and pharyngeal ulceration caused by CMV infection, related to immune reconstitution inflammatory syndrome. In previous reports of CMV-induced pharyngeal or laryngeal ulceration in HIV infection, we found six cases similar to our present case. All cases were diagnosed by biopsy. The present case indicates the importance of biopsy for definitive diagnosis. CMV infection should be considered as a differential diagnosis of pharyngeal ulceration in patients with HIV infection.

Novel Strategies to Combat CMV-Related Cardiovascular Disease

Cytomegalovirus (CMV), a ubiquitous human pathogen that is never cleared from the host, has long been thought to be relatively innocuous in immunocompetent adults, but causes severe complications including blindness, end-organ disease, and death in newborns and in immuno-compromised individuals, such as organ transplant recipients and those suffering from AIDS. Yet even in persons with intact immunity, CMV infection is associated with profound stimulation of immune and inflammatory pathways. Carriers of CMV infection also have an elevated risk of developing cardiovascular complications. In this review, we define the proposed mechanisms of how CMV contributes to cardiovascular disease (CVD), describe current approaches to target CMV, and discuss how these strategies may or may not alleviate cardiovascular complications in those with CMV infection. In addition, we discuss the special situation of CMV coinfection in people with HIV infection receiving antiretroviral therapy, and describe how these 2 viral infections may interact to potentiate CVD in this especially vulnerable population.

Cytomegalovirus Viremia Associated With Increased Mortality in Cryptococcal Meningitis in Sub-Saharan Africa

BACKGROUND

Cryptococcal meningitis and tuberculosis are both important causes of death in persons with advanced human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS). Cytomegalovirus (CMV) viremia may be associated with increased mortality in persons living with HIV who have tuberculosis. It is unknown whether concurrent CMV viremia is associated with mortality in other AIDS-related opportunistic infections.

METHODS

We prospectively enrolled Ugandans living with HIV who had cryptococcal meningitis from 2010-2012. Subsequently, we analyzed stored baseline plasma samples from 111 subjects for CMV DNA. We compared 10-week survival rates among those with and without CMV viremia.

RESULTS

Of 111 participants, 52% (58/111) had detectable CMV DNA (median plasma viral load 498 IU/mL, interquartile range [IQR] 259-2390). All samples tested were positive on immunoglobin G serology. The median CD4+ T cell count was 19 cells/µL (IQR 9-70) and did not differ by the presence of CMV viremia (P = .47). The 10-week mortality rates were 40% (23/58) in those with CMV viremia and 21% (11/53) in those without CMV viremia (hazard ratio 2.19, 95% confidence interval [CI] 1.07-4.49; P = .03), which remained significant after a multivariate adjustment for known risk factors of mortality (adjusted hazard ratio 3.25, 95% CI 1.49-7.10; P = .003). Serum and cerebrospinal fluid cytokine levels were generally similar and cryptococcal antigen-specific immune stimulation responses did not differ between groups.

CONCLUSIONS

Half of persons with advanced AIDS and cryptococcal meningitis had detectable CMV viremia. CMV viremia was associated with an over 2-fold higher mortality rate. It remains unclear whether CMV viremia in severely immunocompromised persons with cryptococcal meningitis contributes directly to this mortality or may reflect an underlying immune dysfunction (ie, cause vs effect).

CLINICAL TRIALS REGISTRATION

NCT01075152.

Where do we Stand after Decades of Studying Human Cytomegalovirus?

Human cytomegalovirus (HCMV), a linear double-stranded DNA betaherpesvirus belonging to the family of Herpesviridae, is characterized by widespread seroprevalence, ranging between 56% and 94%, strictly dependent on the socioeconomic background of the country being considered. Typically, HCMV causes asymptomatic infection in the immunocompetent population, while in immunocompromised individuals or when transmitted vertically from the mother to the fetus it leads to systemic disease with severe complications and high mortality rate. Following primary infection, HCMV establishes a state of latency primarily in myeloid cells, from which it can be reactivated by various inflammatory stimuli. Several studies have shown that HCMV, despite being a DNA virus, is highly prone to genetic variability that strongly influences its replication and dissemination rates as well as cellular tropism. In this scenario, the few currently available drugs for the treatment of HCMV infections are characterized by high toxicity, poor oral bioavailability, and emerging resistance. Here, we review past and current literature that has greatly advanced our understanding of the biology and genetics of HCMV, stressing the urgent need for innovative and safe anti-HCMV therapies and effective vaccines to treat and prevent HCMV infections, particularly in vulnerable populations.

Endogenous endophthalmitis and other ocular manifestations of injection drug use

PURPOSE OF REVIEW

The United States has experienced a dramatic rise in opioid and injection drug use over the past 2 decades. A public health emergency was declared in 2017 and subsequently, there have been several new reports on the rise of endogenous endophthalmitis specifically associated with injection drug use. The purpose of this review is to provide a current perspective of the ocular harms posed by injection drug use.

RECENT FINDINGS

The opioid epidemic has prompted several new studies from New England, one of the US regions most heavily affected, that examine the trends and characteristics of injection drug use-associated endogenous endophthalmitis. Patients may delay seeking care and may be infected with a variety of rare and atypical microbes, and as a result clinical appearance may vary widely. Injection drug use also leads to embolic phenomena such as talc retinopathy and septic emboli from endocarditis. HIV is highly associated with injection drug use and although HAART has drastically reduced the morbidity and mortality of HIV-associated infections, a variety of ocular disease may accompany an immunocompromised patient.

SUMMARY

Healthcare providers must remain vigilant in the recognition of injection drug use patients with vision loss and ocular inflammation to ensure prompt medical and/or surgical treatment.

A rare case of CMV pneumonia in HIV-infection

Cytomegalovirus (CMV) pneumonia is a rare opportunistic infection in the setting of HIV (Human Immunodeficiency Virus)-infection. Establishing accurate diagnosis of CMV pneumonia in HIV-infection can be challenging. Co-infections by multiple opportunistic pathogens are common and a high degree of clinical vigilance to evaluate for multiple infections, including CMV pneumonia, should be maintained. As there can be a degree of overlap in clinical and radiological features amongst different opportunistic infections affecting the lungs, definitive microbiological and cytohistologic evidences are needed. Reliance on microbiological evidence of CMV in respiratory specimens alone for the diagnosis of CMV pneumonia will lead to an over-diagnosis of the condition and unnecessary treatment.

In our case report, we describe a 53-year-old man with recently diagnosed HIV-infection who presented with non-resolving pneumonia. A diagnosis of CMV pneumonia was reached through consistent clinical, radiological, microbiological and cytologic investigations. The patient made a full clinical recovery after being started on anti-CMV treatment.

Diagnostic Difficulties in a Severely Ill HIV Patient with Multiple Superinfections - A Case Report

INTRODUCTION

As chronic HIV infection is prone to co-infections more than any other infectious condition, many severely immune-depressed patients require advanced diagnostic investigations and complex treatment.

CASE REPORT

The case of a 30-year-old severely immune-depressed patient with AIDS, who developed neurological impairment and was diagnosed with encephalitis is presented. Multiple diagnostic approaches had to be used in order to identify the etiologic agents responsible for the clinical, immunological and biological evolution. Despite using advanced laboratory investigations and complex treatment, the patient developed multiple organ dysfunction syndromes that led to a fatal outcome.

CONCLUSIONS

Establishing etiologic relations and treatment priorities in patients with severe immunodeficiency and co-infections can prove difficult, underlining the need of rapid syndromic testing.

Impact of CMV upon immune aging: facts and fiction

Aging is accompanied by significant defects in immunity and compromised responses to new, previously unencountered microbial pathogens. Most humans carry several persistent or latent viruses as they age, interacting with the host immune systems for years. In that context maybe the most studied persistent virus is Cytomegalovirus, infamous for its ability to recruit very large T cell responses which increase with age and to simultaneously evade elimination by the immune system. Here we will address how lifelong CMV infection and the immunological burden of its control might affect immune reactivity and health of the host over time.

Association of Cytomegalovirus DNA and Immunologic Markers of Cardiovascular Disease

BACKGROUND

Persons living with human immunodeficiency virus (HIV) (PLWH) with high cytomegalovirus (CMV)-specific interferon (IFN) γ response have increased numbers of endothelium homing receptor (CX3CR1)+-expressing cells that are associated with cardiovascular disease. The current study was performed to investigate the effect of cellular levels of CMV DNA on these markers.

METHODS

Eighty paired peripheral blood mononuclear cell samples were collected ≥12 months apart from 40 CMV-seropositive PLWH with suppressed HIV RNA, who started antiretroviral therapy at median of 3-months of infection. The samples were assessed for CMV-specific IFN-γ response by means of enzyme-linked immunospot assay, and participants were classified as low responders (LRs) or high responders (HRs) based on IFN-γ production (≤100 or >100 spot-forming units [SFUs]/105 cells).

RESULTS

Of the 40 participants, 26 (65%) were HRs and 14 (35%) LRs at baseline, which did not change over time or by CMV levels (median at first/second time points, 383/308 SFUs/106 cells for HRs vs 21/41 SFUs/106 for LRs). A decrease in IFN-γ over time was associated with higher CMV DNA levels (P < .01). High CMV response was also associated with increased CD28+CD27-CD4+ T cells expressing CX3CR1 (P < .001). Similarly, increased IFN-γ production was associated with increased CMV-specific CX3CR1+CD28+CD27-CD4+ and CD8+ T cells (P < .001).

CONCLUSIONS

These findings demonstrate that levels of CMV-specific IFN-γ response in PLWH are stable over time, and that HRs have increased circulating T cells expressing CX3CR1 that may put them at increased risk of cardiovascular disease and other inflammatory diseases.

Cytomegalovirus colitis in a patient with HIV infection shortly after initiation of antiretroviral therapy

We present a case of a man infected with human immunodeficiency virus (HIV) and who was diagnosed with Cytomegalovirus (CMV) colitis shortly after initiation of antiretroiviral therapy (ART). CMV colitis should be considered in diarrheal patients with HIV infection even after initiation of ART.

Cytomegalovirus Disease in HIV-infected Children-A Single-Centre Clinical Experience over 23 Years

BACKGROUND

Cytomegalovirus (CMV) results in significant morbidity and mortality in Human Immunodeficiency Virus (HIV)-infected individuals. There is paucity of literature on paediatric CMV disease, especially from developing countries.

METHODS

A retrospective review of records of all HIV-infected children with evidence of CMV disease was done.

RESULTS

A total of 15 children were found to have CMV disease (retinitis in all, pneumonia in two and invasive gastrointestinal disease in one). Median CD4+ T cell count and percentage at diagnosis of CMV disease was 64.5 cells/µl and 3.6%, respectively. Intravenous ganciclovir was used in patients with active CMV disease. Of the 15 children, three died while two were lost to follow-up. Symptomatic patients had poor visual outcome and almost all children who were diagnosed on active screening attained normal vision.

CONCLUSION

Retinitis is the most common CMV disease in HIV-infected children. Early detection by active screening and initiation of systemic ganciclovir reduces the morbidity.

Assessment of the gorilla gut virome in association with natural simian immunodeficiency virus infection

Background

Simian immunodeficiency viruses (SIVs) of chimpanzees and gorillas from Central Africa crossed the species barrier at least four times giving rise to human immunodeficiency virus type 1 (HIV-1) groups M, N, O and P. The paradigm of non-pathogenic lentiviral infections has been challenged by observations of naturally infected chimpanzees with SIVcpz associated with a negative impact on their life span and reproduction, CD4⁺ T-lymphocyte loss and lymphoid tissue destruction. With the advent and dissemination of new generation sequencing technologies, novel promising markers of immune deficiency have been explored in human and nonhuman primate species, showing changes in the microbiome (dysbiosis) that might be associated with pathogenic conditions. The aim of the present study was to identify and compare enteric viromes of SIVgor-infected and uninfected gorillas using noninvasive sampling and ultradeep sequencing, and to assess the association of virome composition with potential SIVgor pathogenesis in their natural hosts.

Results

We analyzed both RNA and DNA virus libraries of 23 fecal samples from 11 SIVgor-infected (two samples from one animal) and 11 uninfected western lowland gorillas from Campo-Ma’an National Park (CP), in southwestern Cameroon. Three bacteriophage families (Siphoviridae, Myoviridae and Podoviridae) represented 67.5 and 68% of the total annotated reads in SIVgor-infected and uninfected individuals, respectively. Conversely, mammalian viral families, such as Herpesviridae and Reoviridae, previously associated with gut- and several mammalian diseases were significantly more abundant (p < 0.003) in the SIVgor-infected group. In the present study, we analyzed, for the first time, the enteric virome of gorillas and their association with SIVgor status. This also provided the first evidence of association of specific mammalian viral families and SIVgor in a putative dysbiosis context.

Conclusions

Our results suggested that viromes might be potentially used as markers of lentiviral disease progression in wild gorilla populations. The diverse mammalian viral families, herein described in SIVgor-infected gorillas, may play a pivotal role in a disease progression still unclear in these animals but already well characterized in pathogenic lentiviral infections in other organisms. Larger sample sets should be further explored to reduce intrinsic sampling variation.

Recurrent cytomegalovirus colitis: a rare case of immune reconstitution inflammatory syndrome

Cytomegalovirus (CMV) colitis usually occurs in patients with advanced immunosuppression when the CD4 count is <50 cells/μL. We reported a case of recurrent CMV colitis in a patient with HIV who presented with profuse lower gastrointestinal bleed. This was a case of immune reconstitution inflammatory syndrome (IRIS) manifesting as CMV colitis and has been reported only once in the literature previously. This patient had a CD4 count of 157 cells/μL and undetectable viral load after being on antiretroviral therapy (ART) for 5 months, which was consistent with IRIS. The diagnosis of CMV was confirmed by a colonoscopy and a biopsy. This case highlights the fact that CMV colitis can manifest despite a moderately preserved CD4 count and the clinicians must have a high index suspicion for IRIS syndrome especially when someone was recently started on ART. Since effective treatment is available, it is important not to miss the diagnosis of CMV colitis.

[Wernicke-Korsakoff syndrome secondary to cytomegalovirus encephalitis: A case report]

Cytomegalovirus (CMV) is one of the opportunistic microorganisms with the highest prevalence in immunocompromised patients. Reactivation has decreased after the introduction of highly active antiretroviral therapy (HAART). Encephalitis has been reported in the coinfection as one of the most frequent presentations.We present the case of a young adult patient with HIV infection and rapid neurological deterioration due to classic clinical symptoms and signs of the Wernicke-Korsakoff syndrome, with no risk factors for thiamine deficiency, with images by nuclear magnetic resonance typical of the syndrome, and identification of cytomegalovirus in cerebrospinal fluid. The specific treatment for CMV managed to control the symptoms with neurological sequelae in progression towards improvement.This is one of the few cases reported in the literature of Wernicke syndrome secondary to cytomegalovirus encephalitis.

Effect of cytomegalovirus and Epstein-Barr virus replication on intestinal mucosal gene expression and microbiome composition of HIV-infected and uninfected individuals

BACKGROUND

HIV-infection is associated with dramatic changes in the intestinal mucosa. The impact of other viral pathogens is unclear.

METHODS

One hundred and eight (108) biopsies from left and right colon (n = 79) and terminal ileum (n = 29) were collected from 19 HIV-infected and 22 HIV-uninfected participants. Levels of cytomegalovirus (CMV) and Epstein-Barr virus (EBV) DNA were measured by droplet digital PCR. Mucosal gene expression was measured via multiplex-assay. Microbiome analysis was performed using bacterial 16S-rDNA-pyrosequencing. The effect of CMV and EBV replication on the microbiome composition and mRNA-expression of selected cytokines (IL-6, IFN-γ, IL-1β, CCL2, IL-8, and IFN-β1) was evaluated.

RESULTS

Overall, CMV and EBV were detected in at least one intestinal site in 60.5 and 78.9% of participants, respectively. HIV-infected individuals demonstrated less detectable CMV (PB = 0.02); CMV was more frequently detected in terminal ileum than colon (PB = 0.05). Detectable EBV was more frequent among HIV-infected (P B= 0.04) without differences by intestinal site. The number of operational taxonomic units did not differ by CMV or EBV detection status. Among HIV-infected participants, higher CMV was only associated with lower relative abundance of Actinobacteria in the ileum (P = 0.03). Presence of CMV was associated with upregulated expression of all selected cytokines in the ileum (all P < 0.02) and higher expression of IL-8 and IFN-β1 in the colon (all P < 0.05) of HIV-uninfected participants, but not among HIV-infected. EBV had no effect on cytokine expression or microbiome composition whatsoever.

CONCLUSION

These results illustrate a complex interplay among HIV-infection, intestinal CMV replication, and mucosal gut environment, and highlight a possible modulatory effect of CMV on the microbial and immune homeostasis.

Elevated humoral response to cytomegalovirus in HIV-infected individuals with poor CD4+ T-cell immune recovery

Some HIV-infected c-ART-suppressed individuals show incomplete CD4⁺ T-cell recovery, abnormal T-cell activation and higher mortality. One potential source of immune activation could be coinfection with cytomegalovirus (CMV). IgG and IgM levels, immune activation, inflammation and T-cell death in c-ART-suppressed individuals with CD4⁺ T-cell counts >350 cells/μL (immunoconcordant, n = 133) or <350 cells/μL (immunodiscordant, n = 95) were analyzed to evaluate the effect of CMV humoral response on immune recovery. In total, 27 HIV-uninfected individuals were included as controls. In addition, the presence of CMV IgM antibodies was retrospectively analyzed in 58 immunoconcordant individuals and 66 immunodiscordant individuals. Increased CMV IgG levels were observed in individuals with poor immune reconstitution (p = 0.0002). Increased CMV IgG responses were significantly correlated with lower nadir and absolute CD4⁺ T-cell counts. In contrast, CMV IgG responses were positively correlated with activation (HLA-DR⁺) and death markers in CD4⁺ T-cells and activated memory CD8⁺ T-cells (CD45RA^-CD38⁺). Longitudinal subanalysis revealed an increased frequency of IgM⁺ samples in individuals with poor CD4⁺ T-cell recovery, and an association was observed between retrospective IgM positivity and the current level of IgG. The magnitude of the humoral immune response to CMV is associated with nadir CD4⁺ T-cell counts, inflammation, immune activation and CD4⁺ T-cell death, thus suggesting that CMV infection may be a relevant driving force in the increased morbidity/mortality observed in HIV⁺ individuals with poor CD4⁺ T-cell recovery.

Known unknowns: how might the persistent herpesvirome shape immunity and aging?

The microbial community that colonizes all living organisms is gaining appreciation for its contributions to both physiologic and pathogenic processes. The virome, a subset of the overall microbiome, large and diverse, including viruses that persistently inhabit host cells, endogenous viral elements genomically or epigenomically integrated into cells, and viruses that infect the other (bacterial, protozoan, fungal, and archaeal) microbiome phylla. These viruses live in the organism for its life, and therefore are to be considered part of the aging process experienced by the organism. This review considers the impact of the persistent latent virome on immune aging. Specific attention will be devoted to the role of herpesviruses, and within them, the cytomegalovirus, as the key modulators of immune aging.

Cytomegalovirus and HIV: A Dangerous Pas de Deux

Human immunodeficiency virus (HIV)-infected adults who take stable antiretroviral therapy (ART) are at risk for early onset of age-related diseases. This is likely due to a complex interaction between traditional risk factors, HIV infection itself, and other factors, such as underlying immune dysfunction and persistent inflammation. HIV disrupts the balance between the host and coinfecting microbes, worsening control of these potential pathogens. For example, HIV-infected adults are more likely than the general population to have subclinical bursts of cytomegalovirus (CMV) replication at mucosal sites. Production of antigens can activate the immune system and stimulate HIV replication, and it could contribute to the pathogenesis of adverse outcomes of aging, like cardiovascular disease and neurocognitive impairment. Further investigation of the relationships between CMV, immune dysfunction, and unsuccessful aging during chronic HIV infection is warranted.

Lung microbiome in human immunodeficiency virus infection

The lung microbiome plays a significant role in normal lung function and disease. Because microbial colonization is likely influenced by immunodeficiency, one would speculate that infection with human immunodeficiency virus (HIV) alters the lung microbiome. Furthermore, how this alteration might impact pulmonary complications now seen in HIV-infected patients on antiretroviral therapy (ART), which has shifted from opportunistic infections to diseases associated with chronic inflammation, is not known. There have been limited publications on the lung microbiome in HIV infection, many of them emanating from the Lung HIV Microbiome Project. Current evidence suggests that the lung microbiome in healthy HIV-infected individuals with preserved CD4 counts is similar to uninfected individuals. However, in individuals with more advanced disease, there is an altered alveolar microbiome characterized by a loss of richness and evenness (alpha diversity) within individuals. Furthermore, as a group the taxa making up the HIV-infected and uninfected lung microbiome are different (differences in beta diversity), and the HIV-infected population is more spread out (greater dispersion) than the uninfected population. These differences decline with ART, but even after effective therapy the alveolar microbiome in HIV-infected individuals contains increased amounts of signature bacteria, some of which have previously been associated with chronic lung inflammation. Furthermore, more recent investigations into the lung virome in HIV infection suggest that perturbations in lung viral communities also exist in HIV infection, and that these too are associated with evidence of lung inflammation. Thus, it is likely both microbiome and virome alterations in HIV infection contribute to lung inflammation in these individuals, which has important implications on the changing spectrum of pulmonary complications in patients living with HIV.

Evaluation of T Cell Immunity against Human Cytomegalovirus: Impact on Patient Management and Risk Assessment of Vertical Transmission

Cytomegalovirus (CMV) is one of the most common infectious agents, infecting the general population at an early age without causing morbidity most of the time. However, on particular occasions, it may represent a serious risk, as active infection is associated with rejection and disease after solid organ transplantation or fetal transmission during pregnancy. Several methods for CMV diagnosis are available on the market, but because infection is so common, careful selection is needed to discriminate primary infection from reactivation. This review focuses on methods based on CMV-specific T cell reactivity to help monitor the consequences of CMV infection/reactivation in specific categories of patients. This review makes an attempt at discussing the pros and cons of the methods available.

HCMV Displays a Unique Transcriptome of Immunomodulatory Genes in Primary Monocyte-Derived Cell Types

Human cytomegalovirus (HCMV) is a betaherpesvirus which rarely presents problems in healthy individuals, yet may result in severe morbidity in immunocompromised patients and in immune-naïve neonates. HCMV has a large 235 kb genome with a coding capacity of at least 165 open reading frames (ORFs). This large genome allows complex gene regulation resulting in different sets of transcripts during lytic and latent infection. While latent virus mainly resides within monocytes and CD34+ progenitor cells, reactivation to lytic infection is driven by differentiation towards terminally differentiated myeloid dendritic cells and macrophages. Consequently, it has been suggested that macrophages and dendritic cells contribute to viral spread in vivo. Thus far only limited knowledge is available on the expression of HCMV genes in terminally differentiated myeloid primary cells and whether or not the virus exhibits a different set of lytic genes in primary cells compared with lytic infection in NHDF fibroblasts. To address these questions, we used Illumina next generation sequencing to determine the HCMV transcriptome in macrophages and dendritic cells during lytic infection and compared it to the transcriptome in NHDF fibroblasts. Here, we demonstrate unique expression profiles in macrophages and dendritic cells which significantly differ from the transcriptome in fibroblasts mainly by modulating the expression of viral transcripts involved in immune modulation, cell tropism and viral spread. In a head to head comparison between macrophages and dendritic cells, we observed that factors involved in viral spread and virion composition are differentially regulated suggesting that the plasticity of the virion facilitates the infection of surrounding cells. Taken together, this study provides the full transcript expression analysis of lytic HCMV genes in monocyte-derived type 1 and type 2 macrophages as well as in monocyte-derived dendritic cells. Thereby underlining the potential of HCMV to adapt to or influence different cellular environments to promote its own survival.

HIV patients stable on ART retain evidence of a high CMV load but changes to Natural Killer cell phenotypes reflect both HIV and CMV

Background

Whilst ART corrects many effects of HIV disease, T cell populations retain features of accelerated immunological aging.

Methods

Here we analyse phenotypic changes to natural killer (NK) cells in HIV patients who began ART with <200 CD4 T-cells/µl and maintained virological control for 12–17 years, compared with CMV seropositive and seronegative healthy control donors.

Results

Humoral responses to CMV antigens (lysate, gB, IE-1) remain elevated in the patients (P < 0.0001) despite the long duration of ART. Patient’s NK cells responded poorly to K562 cells when assessed by CD107a and IFNγ, but this could not be attributed to CMV as responses were low in CMV-seronegative controls. Moreover HIV (and not CMV) increased expression of CD57 on CD56^lo cells.

Conclusions

Comparisons with published studies suggest that CMV accelerates age-related increases in CD57 expression but levels plateau by 60–70 years of age, so the effect of CMV disappears. In HIV patients the plateau is higher and perhaps reached sooner.

Electronic supplementary material

The online version of this article (doi:10.1186/s12981-015-0080-9) contains supplementary material, which is available to authorized users.

Epigenetic regulation of human cytomegalovirus latency: an update

Human cytomegalovirus (HCMV) is a ubiquitous virus which infects 50-90% of the population worldwide. In immunocompetent hosts, HCMV either remains unnoticed or causes mild symptoms. Upon primary infection it establishes latent infection in a few cells. However, in certain situations where immunity is either immature or compromised, HCMV may reactivate and cause mortality and morbidity. Therefore, it is utmost important to understand how HCMV establishes latent infection and associated mechanisms responsible for its reactivation. Several mechanisms are involved in the regulation of latency including chromatin remodeling by an array of enzymes and microRNAs. Here we will describe the epigenetic regulation of HCMV latency. Further we will discuss the unique HCMV latency signature and patho-physiological relevance of latent HCMV infection.

Acute Confusional State: A Manifestation of Toxoplasma and CMV Co-infection in HIV Patient

Context:

When dealing with a patient with HIV that presents with an altered mental status, there are various infections and disease etiologies a physician has to rule out that may play a role in complicating the inherent complex nature of HIV. Toxoplasma gondii (T. gondii) and cytomegalovirus (CMV) affect a large part of the world's population and lead to a varied and broad symptomatology depending upon the severity of HIV, the CD4 count and how early the infection is diagnosed.

Case Report:

We report an HIV+ patient in his early 50s and with a low CD4 count that presented with severe lethargy and confusion. Imaging studies that were performed after stabilizing the patient revealed a ring-enhancing lesion in the brain and after further testing, a diagnosis of reactivated T. gondii with co-infection with CMV was made. Patients infected with T. gondii that are already immune-compromised deteriorate rapidly and the disease diagnosis poses several challenges.

Conclusion:

Clinicians have to be extremely careful about making a prompt diagnosis and initiate treatment without delay before the infection takes a deadly toll on the patient. Since our patient was not on the required prophylactic medication to prevent infection with T. gondii, it was imperative to start treatment in a timely manner and to monitor the patient for any further decline in functioning.

Glucocorticosteroids trigger reactivation of human cytomegalovirus from latently infected myeloid cells and increase the risk for HCMV infection in D+R+ liver transplant patients

Graft rejection in transplant patients is managed clinically by suppressing T-cell function with immunosuppressive drugs such as prednisolone and methylprednisolone. In such immunocompromised hosts, human cytomegalovirus (HCMV) is an important opportunistic pathogen and can cause severe morbidity and mortality. Currently, the effect of glucocorticosteroids (GCSs) on the HCMV life cycle remains unclear. Previous reports showed enhanced lytic replication of HCMV in vitro in the presence of GCSs. In the present study, we explored the implications of steroid exposure on latency and reactivation. We observed a direct effect of several GCSs used in the clinic on the activation of a quiescent viral major immediate-early promoter in stably transfected THP-1 monocytic cells. This activation was prevented by the glucocorticoid receptor (GR) antagonist Ru486 and by shRNA-mediated knockdown of the GR. Consistent with this observation, prednisolone treatment of latently infected primary monocytes resulted in HCMV reactivation. Analysis of the phenotype of these cells showed that treatment with GCSs was correlated with differentiation to an anti-inflammatory macrophage-like cell type. On the basis that these observations may be pertinent to HCMV reactivation in post-transplant settings, we retrospectively evaluated the incidence, viral kinetics and viral load of HCMV in liver transplant patients in the presence or absence of GCS treatment. We observed that combination therapy of baseline prednisolone and augmented methylprednisolone, upon organ rejection, significantly increased the incidence of HCMV infection in the intermediate risk group where donor and recipient are both HCMV seropositive (D+R+) to levels comparable with the high risk D+R- group.

Clinical relevance of the plasma load of cytomegalovirus in patients infected with HIV--a survival analysis

To investigate whether asymptomatic cytomegalovirus (CMV) viraemia impact the course of human immunodeficiency virus (HIV) infection, this study evaluated the effect of CMV replication on progression of newly-diagnosed HIV infected individuals towards AIDS events and death. In a 3-year prospective study on co-infected patients, clinical, immunological, and virological tests were performed in a national reference hospital quarterly. CMV viraemia was quantified by RoboGene® HCMV DNA Quantification Kit (Analytik Jena, Germany), on ABI Prism® 7000 Sequence Detection System (Applied Biosystems, USA). One hundred and five patients were enrolled with a balanced sex distribution and a median age of 30.7 years. Median CD4(+) cell count at enrollment was 164/mm(3) and median HIV RNA 4.6 log10 copies/ml. Detectable CMV viraemia was found in 25.7% of the patients. Kaplan-Meier analysis showed progression of HIV infection to be significantly increased in those with active CMV replication and/or low CD4(+) cell count. Cox regression indicated the risk of developing new AIDS events was 2.6 times greater in patients with detectable CMV viraemia versus those without (CI95% 1-6.6; P = 0.04). Also in multivariate analysis, the overall risk of progression to AIDS events or death was 3-fold higher in those with detectable CMV viraemia (CI95% 1.3-6.7; P = 0.008) and 2.3-fold higher if CD4(+) cell count was below 100/mm(3) (CI95% 1-5.1; P = 0.04). In these young Romanian HIV-seropositives, active CMV replication increased morbidity, even when treated with combination antiretroviral therapy. Further studies are needed to evaluate if serial quantitative CMV-DNA levels might correlate with non-infectious inflammation-related risks in patients with HIV and active CMV infection.

Recent developments in human cytomegalovirus diagnosis

Since the early 1990s, great efforts have been made in the field of human cytomegalovirus (HCMV) diagnosis. Besides HCMV diagnosis in immunosuppressed patients (solid organ transplant recipients, hematopoietic stem cell transplant patients and AIDS patients), diagnosis in connection with congenital HCMV infection is of great interest. This review focuses on the development and clinical utility of serological assays, as well as on virological tests (molecular and nonmolecular assays). Interpretation of these tests is strongly dependent on the patient group (solid organ transplant recipients and hematopoietic stem cell transplant patients) and whether the tests are used for screening, risk stratification or diagnosis. Furthermore, a better understanding of HCMV infection has led to new approaches in HCMV diagnosis and monitoring. Thus, assays for viral resistance testing and assays for monitoring the HCMV-specific cellular immune response are increasingly important for the guidance of antiviral therapy.

[Immune reconstitution syndrome]

The immune reconstitution inflammatory syndrome (IRIS) represents a heterogeneous group of conditions. Whilst they typically present in HIV-infected patients with advanced immunodeficiency, IRIS have also been described in HIV-negative patients with immune reconstitution due to other causes of immunosuppression. Frequently IRIS results from an immune response against underlying infection (pathogen-associated IRIS). However, IRIS might become evident during immune reconstitution without an underlying pathogen such as a sarcoid-like illness or an autoimmune thyropathy. Here we report on the epidemiology and risk factors of IRIS along with diagnosis and management of this clinically important inflammatory syndrome.

Evaluation of glycoprotein B genotypes and load of CMV infecting blood leukocytes on prognosis of AIDS patients

BACKGROUND

Cytomegalovirus (CMV) remains an important pathogen to immunocompromised patients even in the era of HAART. The present study aimed at evaluating the influence of CMV viral load and its gB genotypes on AIDS patients' outcome.

METHODS

Blood samples of 101 AIDS patients were collected and tested for HIV load, CD4 - cell count and opportunistic pathogens, including CMV. Semi-nested PCRs were run to detect CMV genome and in the positive samples, gB genotyping and CMV load were established using enzymatic restriction and real time PCR, respectively. All patients were clinically followed for four years.

RESULTS

In thirty patients (31%) CMV was detected and all fatal cases (n = 5) occurred in this group of patients (p = 0.007), but only two patients had CMV disease (1.9%). However, viral load was not statistically associated with any analyzed parameter. The most frequently observed CMV genotype was gB2 (45.16%) followed by gB3 (35.48%). gB2 genotype was more frequently found in patients with CD4-cell counts under 200 cells/mm³ (p = 0.0017), and almost all fatal cases (80%) had gB2 genotype.

CONCLUSIONS

Our study suggests that CMV and its polymorphisms in biologically relevant genes, such as the gB encoding ORF, may still influence the prognosis and outcome of AIDS patients. The gB2 genotype was associated to patient's bad outcome.

HIV-1 matrix protein p17: a candidate antigen for therapeutic vaccines against AIDS

The success in the development of anti-retroviral therapies (HAART) that contain human immunodeficiency virus type 1 (HIV-1) infection is challenged by the cost of this lifelong therapy and by its toxicity. Immune-based therapeutic strategies that boost the immune response against HIV-1 proteins or protein subunits have been recently proposed to control virus replication in order to provide protection from disease development, reduce virus transmission, and help limit the use of anti-retroviral treatments. HIV-1 matrix protein p17 is a structural protein that is critically involved in most stages of the life cycle of the retrovirus. Besides its well established role in the virus life cycle, increasing evidence suggests that p17 may also be active extracellularly in deregulating biological activities of many different immune cells that are directly or indirectly involved in AIDS pathogenesis. Thus, p17 might represent a promising target for developing a therapeutic vaccine as a contribution to combating AIDS. In this article we review the biological characteristics of HIV-1 matrix protein p17 and we describe why a synthetic peptide representative of the p17 functional epitope may work as a vaccine molecule capable of inducing anti-p17 neutralizing response against p17 derived from divergent HIV-1 strains.

Human Cytomegalovirus Infection Among Patients Living With AIDS in a Tertiary Level Hospital in India

Objective: Detecting the prevalence of human cytomegalovirus (CMV) coinfection in HIV-infected individuals attending a tertiary care hospital in Delhi by using 3 laboratory tests namely pp65 antigenemia assay, CMV DNA polymerase chain reaction (PCR), and immunoglobulin M (IgM) enzyme-linked immunosorbent assay (ELISA) for anti-CMV antibody. Design: HIV seropositive patients with CD4 count ≤100 cells/mm3 were included as cases and HIV-negative healthy individuals as controls. Blood samples were collected from all participants and 3 tests were performed. Methods: pp65 antigenemia assay and IgM ELISA were performed by commercially available kits; PCR was performed by an in-house nested PCR method. Results: In all, 7.1%, 5.7%, and 2.9% were positive for pp65 antigenemia, CMV DNA, and IgM antibody against CMV, respectively. On the basis of pp65 and/or PCR positivity, it can be said that active CMV coinfection was present in 8.57% of the cases. Conclusion: In the post-antiretroviral therapy (ART) era, CMV coinfection in HIV-infected patients has significantly declined.

[Massive alveolar hemorrhage due to cytomegalovirus (CMV) and HIV infection]

Alveolar hemorrhage may be a complication of diseases with local and systemic manifestations. Both share the same pathophysiological concept: damage to the alveolar microcirculation. It is a clinical entity that generates a diagnostic challenge for the physician. Early recognition favors aggressive treatment, which can improve the outcome. Despite the technological advances in its diagnosis and treatment, it is still a condition having high morbidity and mortality. We present the case of a 42-year old woman diagnosed of massive alveolar hemorrhage induced by cytomegalovirus (CMV) and HIV infection. Its presentation is atypical because most reported cases have occurred as a pneumonic process, episodes of massive hemorrhage being uncommon. The diagnosis was documented by bronchoscopy with bronchoalveolar lavage and etiological diagnosis with molecular techniques using reverse transcription polymerase chain reaction.

The microvascular endothelium in scleroderma

Vascular endothelial injury in SSc leads to a host of pathological changes in the blood vessels that adversely impact the physiology of many organ systems and eventually results in a state of chronic tissue ischaemia. Current hypotheses in SSc vascular disease pathogenesis suggest a possible infectious or chemical trigger(s) that activates both cellular and humoral immunity. Products of immune activation may lead to vascular injury possibly through the production of autoantibodies and the release of products of activated T cells that can directly damage the endothelium. Knowledge of the initial trigger of immune activation in SSc may offer an opportunity to develop a multiple step strategy for therapeutic intervention.

Antiretroviral therapy in AIDS patients with CMV disease: impact on the survival and long-term treatment outcome

OBJECTIVES

To determine the impact of antiretroviral therapy (ART) on the long-term survival of AIDS patients with CMV disease and evaluate long-term outcomes of ART.

METHODS

A retrospective cohort study was conducted among HIV-infected patients with CMV disease in a medical school hospital during 1996-2005 and followed-up until June 2007.

RESULTS

There were 154 patients, mean age 34.5 years and 57.8% were male. Organ involvement of CMV disease included retina (94.8%), central nervous system, lungs, and gastrointestinal tract. Median CD4 cell count was 20 cells/mm(3) and 99 patients received ART. During median follow-up of 32 months (interquartile range 23-96), 29.2% of patients died. From Kaplan-Meier analysis, median survival is significantly longer in patients receiving ART (>116.2 vs. 21.6 months, log-rank test, p<0.001). From Cox's proportional hazard model, ART (HR 0.6, p<0.001) and previous opportunistic infections (HR 3.5, p=0.025) were negatively and positively associated with death, respectively. At median time of 69 months (interquartile range 34-101) in patients who received ART, 80.8% had HIV-1 RNA <50 copies/mL and median CD4 was 421 cells/mm(3). One patient had immune reconstitution syndrome at 3 months after initiation of ART and resulted in permanent vision loss.

CONCLUSIONS

ART significantly improves long-term survival of AIDS patients with CMV disease. Long-term virological and immunological outcomes are durable.

Characterization of the DNA- and dNTP-binding activities of the human cytomegalovirus DNA polymerase catalytic subunit UL54

The catalytic subunit of the human cytomegalovirus DNA polymerase is critical for the replication of the virus. In the present study, we report the expression and purification of a recombinant catalytic subunit of the human cytomegalovirus DNA polymerase expressed in bacteria which retains polymerase activity. As a first step towards elucidating the nature of the interaction between the enzyme, DNA and dNTPs, we have utilized endogenous tryptophan fluorescence to evaluate the binding of ligands to the enzyme. Using this technique, we demonstrate that the minimal DNA-binding site of the enzyme is 6 nt. We also report the first detailed study of the binding kinetics and thermodynamic parameters involved in the interaction between the enzyme, DNA and dNTPs. Our thermodynamic analyses indicate that the initial formation of the enzyme-DNA binary complex is driven by a favourable entropy change, but is also clearly associated with an unfavourable enthalpic contribution. In contrast, the interaction of dNTPs to the binary complex was shown to depend on a completely different mode of binding that is dominated by a favourable enthalpy change and associated with an unfavourable entropy change. In order to provide additional insights into the structural modifications that occur during catalysis, we correlated the effect of DNA and dNTP binding on protein structure using CD. Our results indicate that the enzyme undergoes a first conformational change upon the formation of the protein-DNA binary complex, which is followed by a second structural modification upon dNTP binding. The present study provides a better understanding of the molecular basis of DNA and dNTP recognition by the catalytic subunit of the human cytomegalovirus DNA polymerase.

Characterization of the human cytomegalovirus gH/gL/UL128-131 complex that mediates entry into epithelial and endothelial cells

The entry of human cytomegalovirus (HCMV) into biologically relevant epithelial and endothelial cells involves endocytosis followed by low-pH-dependent fusion. This entry pathway is facilitated by the HCMV UL128, UL130, and UL131 proteins, which form one or more complexes with the virion envelope glycoprotein gH/gL. gH/gL/UL128-131 complexes appear to be distinct from the gH/gL/gO complex, which likely facilitates entry into fibroblasts. In order to better understand the assembly and protein-protein interactions of gH/gL/UL128-131 complexes, we generated HCMV mutants lacking UL128-131 proteins and nonreplicating adenovirus vectors expressing gH, gL, UL128, UL130, and UL131. Our results demonstrate that UL128, UL130, and UL131 can each independently assemble onto gH/gL scaffolds. However, the binding of individual UL128-131 proteins onto gH/gL can significantly affect the binding of other proteins; for example, UL128 increased the binding of both UL130 and UL131 to gH/gL. Direct interactions between gH/UL130, UL130/UL131, gL/UL128, and UL128/UL130 were also observed. The export of gH/gL complexes from the endoplasmic reticulum (ER) to the Golgi apparatus and cell surface was dramatically increased when all of UL128, UL130, and UL131 were coexpressed with gH/gL (with or without gO expression). Incorporation of gH/gL complexes into the virion envelope requires transport beyond the ER. Thus, we concluded that UL128, UL130, and UL131 must all bind simultaneously onto gH/gL for the production of complexes that can function in entry into epithelial and endothelial cells.

Shift of CMV-specific CD4+ T-cells to the highly differentiated CD45RO-CD27- phenotype parallels loss of proliferative capacity and precedes progression to HIV-related CMV end-organ disease

To identify factors related to progression to CMV end-organ disease, cytokine production, proliferative capacity and phenotype of CMV-specific CD4(+) T-cells were analysed longitudinally. Numbers of IFNgamma(+)CD4(+) and IFNgamma(+)IL-2(+)CD4(+) T-cells tended to decrease in individuals progressing to AIDS with CMV end-organ disease (AIDS-CMV), whereas they remained detectable in long-term asymptomatics (LTAs) and progressors to AIDS with opportunistic infections (AIDS-OI). In parallel, CMV-specific proliferative capacity was lost in AIDS-CMV. Initially, the majority of the CMV-specific IFNgamma(+)CD4(+) T-cells were of the CD45RO(+)CD27(-) subset, but during progression to AIDS-CMV a shift in phenotype to the CD45RO(-)CD27(-) subset was observed. Our data indicate that a decrease in CMV-specific cytokine production and proliferative capacity precedes progression to AIDS-CMV. Accumulation of CD4(+) T-cells with a CD45RO(-)CD27(-) phenotype suggests that persistent antigen exposure drives differentiation of CMV-specific CD4(+) T-cells towards a poorly proliferating, and highly differentiated "effector" subset, which eventually fails to produce IFNgamma in patients developing AIDS-CMV.

Maintenance of HIV-specific central and effector memory CD4 and CD8 T cells requires antigen persistence

The HIV-specific central and effector CD4 and CD8 memory T cell populations disappear from the peripheral blood of infected individuals under highly active antiretroviral therapy (HAART) with a mean half-life of 6.0 and 7.7 months, respectively. By contrast, cytomegalovirus (CMV)-specific responses are stable or increase. The striking quantitative differences between T cell memory to two persistent viral infections are instructive as to how antigen dosage contributes to the maintenance of antigen-specific memory T cell responses in humans.

High prevalence of multiple human herpesviruses in saliva from human immunodeficiency virus-infected persons in the era of highly active antiretroviral therapy

Human immunodeficiency virus (HIV) infection is associated with an increased risk for human herpesviruses (HHVs) and their related diseases. Methods for limiting the transmission of HHVs require a better understanding of the prevalence and infectiousness of oral HHVs in HIV-infected patients. We performed quantitative PCR to investigate the prevalence, quantity, risk, and correlates of salivary HHVs from 58 HIV-seropositive individuals in a case control study. HHVs were significantly more prevalent in the salivas of HIV-seropositive persons than in those of the controls (odds ratios [ORs], 4.2 to 26.2; P<or=0.008). In HIV-infected patients, Epstein-Barr virus (EBV), human herpesvirus 8 (HHV-8), cytomegalovirus (CMV), and herpes simplex virus type 1 (HSV-1) were detected in 90%, 57%, 31% and 16% of samples, respectively, compared with 48%, 24%, 2%, and 2%, respectively, of samples from controls. Multiple HHVs were observed in 71% of HIV-seropositive persons and only 16% of controls (OR, 13.0; 95% confidence interval, 5.29 to 32.56). HIV-positive patients had significantly higher EBV loads than HIV-negative persons (P<0.0001). HIV-infected patients with CD4 counts above 200 cells/microl had increased probability for having HHV-8 in saliva (P=0.009) compared with patients whose counts were less than 200. In contrast, HSV-1, EBV, and CMV were detected more often when CD4 counts were low. High salivary HHV loads were detected for those (n=7) with oral lesions. These findings suggest that saliva is a potential risk factor for the acquisition of multiple HHVs, and several host factors may function to accelerate HHV reactivation or replication in patients with HIV infection.

Experimental study on the action of allitridin against human cytomegalovirus in vitro: Inhibitory effects on immediate-early genes

Garlic (Allium sativum) extraction has been reported having anti-HCMV efficacy. This study was aimed to investigate the effect of allitridin (diallyl trisulfide, a compound from A. sativum extraction) on the replication of HCMV and the expression of viral immediate-early genes. In HCMV plaque-reduction assay, allitridin appeared a dose-dependent inhibitory ability with EC(50) value of 4.2 microg/ml (selective index, SI=16.7). Time-of-addition and time-of-removal studies showed that allitridin inhibited HCMV replication in earlier period of viral cycle before viral DNA synthesis. Both immediate early gene (ie1) transcription and IEA (IE(1)72 and IE(2)86) expression was suppressed by allitridin, but not by GCV in a single HCMV cycle format. In addition, allitridin appeared stronger inhibition on IE(2)86 than on IE(1)72. Decrease of viral DNA load in infected cells was also detected under allitridin treatment, probably due to an indirect consequence of the reduction in ie gene transcription. In summary, this study indicated that allitridin has anti-HCMV activity and the mechanism is associated with suppression of ie gene transcription.

Cytomegalovirus-specific cell-mediated immunity in HIV-infected children on HAART

The objectives of this study were to define the magnitude, time course, and virologic and immunologic correlates of HAART-associated reconstitution of cytomegalovirus (CMV)-specific cell-mediated immunity (CMI) in pediatric HAART recipients. Thirty-five HIV-infected CMV-seropositive subjects < or = 22 years on or about to receive HAART had CMV-CMI measured by responder cell frequency (RCF) and interferon-gamma (IFN-gamma) secretion over 3 years. RCF was detected in 33, 52, 38, and 28% before HAART and at years 1, 2, and > or = 3, respectively. Corresponding percentages for IFN-gamma were 100, 85, 100, and 38%. Neither RCF nor IFN-gamma was significantly associated with CD4% before or after HAART initiation. Lower HIV replication was associated with a higher proportion of subjects with positive RCF, but not IFN-gamma. There were no clinical CMV manifestations during the study. HIV-infected children did not demonstrate a significant increase in CMV-CMI with longer HAART duration, which suggests that CMV immunereconstitution involves more complex immunologic and virologic interactions than previously anticipated.

Role of helix P of the human cytomegalovirus DNA polymerase in resistance and hypersusceptibility to the antiviral drug foscarnet

Mutations in the human cytomegalovirus DNA polymerase (UL54) can not only decrease but also increase susceptibility to the pyrophosphate (PP(i)) analogue foscarnet. The proximity of L802M, which confers resistance, and K805Q, which confers hypersusceptibility, suggests a possible unifying mechanism that affects drug susceptibility in one direction or the other. We found that the polymerase activities of L802M- and K805Q-containing mutant enzymes were literally indistinguishable from that of wild-type UL54; however, susceptibility to foscarnet was decreased or increased, respectively. A comparison with the crystal structure model of the related RB69 polymerase suggests that L802 and K805 are located in the conserved alpha-helix P that is implicated in nucleotide binding. Although L802 and K805 do not appear to make direct contacts with the incoming nucleotide, it is conceivable that changes at these residues could exert their effects through the adjacent, highly conserved amino acids Q807 and/or K811. Our data show that a K811A substitution in UL54 causes reductions in rates of nucleotide incorporation. The activity of the Q807A mutant is only marginally affected, while this enzyme shows relatively high levels of resistance to foscarnet. Based on these data, we suggest that L802M exerts its effects through subtle structural changes in alpha-helix P that affect the precise positioning of Q807 and, in turn, its presumptive involvement in binding of foscarnet. In contrast, the removal of a positive charge associated with the K805Q change may facilitate access or increase affinity to the adjacent Q807.