Evaluation of the pathogenesis of decreasing CD4(+) T cell counts in human immunodeficiency virus type 1-infected patients receiving successfully suppressive antiretroviral therapy

Viral Load Suppression in People Living with HIV Before and During the COVID-19 Pandemic in Brooklyn, New York

Consistent care is crucial for the health maintenance of people living with human immunodeficiency virus (HIV) (PWH). The coronavirus 2019 (COVID-19) epidemic disrupted patient care in New York City (NYC), yet few studies investigated the association between COVID-19 and viral load suppression in PWH in NYC. This study aims to assess how the COVID-19 pandemic impacted HIV viral load and CD4 + T-cell counts in PWH. Medical records of 1130 adult HIV patients who visited the Special Treatment and Research Health Center in Brooklyn, NY, between January 2019 and May 2023 were compared across three timeframes (pre-pandemic, January 1, 2019 to December 31, 2019; first pandemic phase, March 19, 2020 to December 31, 2020; and second pandemic phase, January 1, 2021 to May 11, 2023). Demographic and clinical variables (e.g. viral load and CD4 + T cell count) were assessed. About 40% of patients did not have routine laboratory monitoring during the first pandemic phase compared with pre-pandemic. The mean HIV viral load was higher during the second pandemic phase compared with pre-pandemic (p = 0.009). The percentages of patients with undetectable HIV viral load and numbers (mm3) of CD4 + T-cells were similar for all time periods. These findings indicate that the COVID-19 pandemic may have exacerbated challenges for individuals who already had barriers to medication adherence or access. However, most individuals remained consistently on their antiretrovirals throughout the pandemic. Further studies are warranted to determine how to mitigate the impact of future pandemics for the health of PWH.

Nicotinamide mononucleotide impacts HIV-1 infection by modulating immune activation in T lymphocytes and humanized mice

BACKGROUND

HIV-1-associated immune activation drives CD4+ T cell depletion and the development of acquired immunodeficiency syndrome. We aimed to determine the role of nicotinamide mononucleotide (NMN), the direct precursor of nicotinamide adenine dinucleotide (NAD) co-enzyme, in CD4+ T cell modulation during HIV-1 infection.

METHODS

We examined HIV-1 integrated DNA or transcribed RNA, intracellular p24 protein, and T cell activation markers in CD4+ T cells including in vitro HIV-1-infected cells, reactivated patient-derived cells, and in HIV-1-infected humanized mice, under NMN treatment. RNA-seq and CyTOF analyses were used for investigating the effect of NMN on CD4+ T cells.

FINDINGS

We found that NMN increased the intracellular NAD amount, resulting in suppressed HIV-1 p24 production and proliferation in infected CD4+ T cells, especially in activated CD25+CD4+ T cells. NMN also inhibited CD25 expression on reactivated resting CD4+ T cells derived from cART-treated people living with HIV-1 (PLWH). In HIV-1-infected humanized mice, the frequency of CD4+ T cells was reconstituted significantly by combined cART and NMN treatment as compared with cART or NMN alone, which correlated with suppressed hyperactivation of CD4+ T cells.

INTERPRETATION

Our results highlight the suppressive role of NMN in CD4+ T cell activation during HIV-1 infection. It warrants future clinical investigation of NMN as a potential treatment in combination with cART in PLWH.

FUNDING

This work was supported by the Hong Kong Research Grants Council Theme-Based Research Scheme (T11-706/18-N), University Research Committee of The University of Hong Kong, the Collaborative Research with GeneHarbor (Hong Kong) Biotechnologies Limited and National Key R&D Program of China (Grant2021YFC2301900).

Telmisartan Therapy Does Not Improve Lymph Node or Adipose Tissue Fibrosis More Than Continued Antiretroviral Therapy Alone

Background

Fibrosis in lymph nodes may limit CD4+ T-cell recovery, and lymph node and adipose tissue fibrosis may contribute to inflammation and comorbidities despite antiretroviral therapy (ART). We hypothesized that the angiotensin receptor blocker and peroxisome proliferator-activated receptor γ agonist telmisartan would decrease lymph node or adipose tissue fibrosis in treated human immunodeficiency virus type 1 (HIV) infection.

Methods

In this 48-week, randomized, controlled trial, adults continued HIV-suppressive ART and received telmisartan or no drug. Collagen I, fibronectin, and phosphorylated SMAD3 (pSMAD3) deposition in lymph nodes, as well as collagen I, collagen VI, and fibronectin deposition in adipose tissue, were quantified by immunohistochemical analysis at weeks 0 and 48. Two-sided rank sum and signed rank tests compared changes over 48 weeks.

Results

Forty-four participants enrolled; 35 had paired adipose tissue specimens, and 29 had paired lymph node specimens. The median change overall in the percentage of the area throughout which collagen I was deposited was -2.6 percentage points (P = 0.08) in lymph node specimens and -1.3 percentage points (P = .001) in adipose tissue specimens, with no between-arm differences. In lymph node specimens, pSMAD3 deposition changed by -0.5 percentage points overall (P = .04), with no between-arm differences. Telmisartan attenuated increases in fibronectin deposition (P = .06). In adipose tissue, changes in collagen VI deposition (-1.0 percentage point; P = .001) and fibronectin deposition (-2.4 percentage points; P < .001) were observed, with no between-arm differences.

Conclusions

In adults with treated HIV infection, lymph node and adipose tissue fibrosis decreased with continued ART alone, with no additional fibrosis reduction with telmisartan therapy.

CD8+ T cells with high TGF‑β1 expression cause lymph node fibrosis following HIV infection

Lymph node (LN) fibrosis resulting in cluster of differentiation (CD) 4+ T cell reduction following human immunodeficiency virus (HIV) infection is an important step in the pathogenesis of acquired immunodeficiency syndrome. The mechanisms mediating LN fibrosis following HIV infection have not been completely elucidated. In order to investigate the mechanism of LN fibrosis, the expression of transforming growth factor (TGF)‑β1 was determined in the LNs of HIV‑infected individuals by immunohistochemistry and fluorescence‑based flow cytometry. The effect of stimulated CD8+ T cells on collagen secretion by fibroblasts was detected using immunofluorescence staining and western blot analysis. The results demonstrated that the LNs of HIV‑infected individuals exhibited a significantly increased proportion of CD8+ T cells with high TGF‑β1 expression. These CD8+ T cells demonstrated increased CD38 and programmed cell death protein 1 expression and decreased CD127 expression compared with the controls. CD8+ T cells from the LNs of non‑HIV infected individuals expressed a high TGF‑β1 level following stimulation with phorbol‑12‑myristate 13‑acetate. These CD8+T cells subsequently induced the secretion of a large amount of type I collagen in human lymphatic fibroblasts. The results of the present study indicated that CD8+ T cells with high TGF‑β1 expression served an important role in LN fibrosis following HIV infection.

Rapid CD4 decline prior to antiretroviral therapy predicts subsequent failure to reconstitute despite HIV viral suppression

HIV-1 infection is characterized by loss of CD4T cells, leading to immunodeficiency. Initiation of antiretroviral therapy (ART) results in suppression of the viral load and increased CD4 counts. Both viral and host factors determine CD4 cell responses to ART with approximately 15-30% of individuals having suboptimal increase of CD4T cell count, most commonly due to lack of compliance to ART. A smaller fraction of patients will have immune reconstitution failure and suboptimal CD4 increase despite suppression of HIV replication, and these individuals are at risk for adverse health outcomes. We sought to characterize the factors associated with decreased immunological response among Manitoba's HIV patient population. This retrospective case-control study included HIV patients with immune reconstitution failure despite suppression of HIV replication by ART. The immune reconstitution failure was defined by CD4 cell count increase from baseline of less than 100 CD4 cells/mm³ or lack of increase to above 200 CD4 cells/mm³ within one year of viral load suppression. Age and nadir CD4 cell counts are known risk factors associated with immune reconstitution failure. We chose controls (Patients with immune reconstitution success) of similar age and CD4 nadir cell with cases (Patients with immune reconstitution failure). We explored the potential effects of gender, HLA type, presence of co-infection, ethnicity, ART type, and rate of pre-treatment CD4 decline among cases and controls. Of more than 550 patients followed by our HIV clinic, 42 individuals met our definition of immune reconstitution failure and they were assigned to the cases group. 31 patients, comprising a range of ages and CD4 nadirs similar to those of the cases, were assigned to the control group. Our primary analysis was a regression model, predicting post-ART change in CD4 over time. After controlling for age and nadir CD4 cell counts, the only potential predictor that appears consistently associated with the rate of post-ART rise in CD4 over time in our cohort, regardless of the other variables that we have controlled for, is the rate of decline in CD4 pre-ART initiation. Several factors have been variably correlated with immune reconstitution failure of CD4 T cell count. Age and low CD4 nadir are factors previously shown to correlate with immune reconstitution failure; and we have controlled for them in our study. Another possible predictor is the rate of decline in CD4 pre-ART, which can serve as an additional marker of reconstitution failure and necessitate prioritizing individuals to ART initiation or identification of a subset of individuals that may be targeted for future adjunct strategies to improve immune recovery.

Cardiovascular Disease, Statins, and HIV

Human immunodeficiency virus (HIV)-infected patients are at an increased risk of serious, non-AIDS-defining comorbidities, even in the setting of viral suppression with combination antiretroviral therapy. This increased risk is due in part to immune dysfunction and heightened inflammation and immune activation associated with chronic HIV infection. Statins have wide-reaching immunomodulatory effects, and their use in the HIV-infected population may be of particular benefit. In this article, we review the pathogenesis of increased inflammation during HIV infection and how it contributes to the risk of cardiovascular disease among HIV-infected individuals. We then we review the immunomodulatory effects of statins and how they may attenuate the risk of cardiovascular disease and other comorbidities in this unique patient population.

Combining Cell and Gene Therapy in an Effort to Eradicate HIV

More than 30 million people are infected with HIV, and HIV remains the fifth leading cause of disability-adjusted life years worldwide. Antiretroviral therapy (ART) dramatically decreases mortality rate, but there are side effects, long-term toxicities, expenses, stigmas, and inconveniences associated with chronic treatment, and HIV-infected individuals on ART have an increased risk of malignancies, cardiovascular disease, neurologic disease, and shortened life expectancy. Therefore, a cure for HIV remains an important goal. Combining new cell and gene therapy technology is an exciting approach that appears promising in vitro. Animal testing and careful clinical trials will be needed to determine if these strategies are clinically useful.

Role of intestinal myofibroblasts in HIV-associated intestinal collagen deposition and immune reconstitution following combination antiretroviral therapy

OBJECTIVE

To investigate the potential role of mucosal intestinal myofibroblasts (IMFs) in HIV and associated fibrosis in gut-associated lymphoid tissue.

DESIGN

Profibrotic changes within the secondary lymphoid organs and mucosa have been implicated in failed immune reconstitution following effective combination antiretroviral therapy (cART). Microbial translocation is believed to be sustaining these systemic inflammatory pathways. IMFs are nonprofessional antigen-presenting cells with both immunoregulatory and mesenchymal functions that are ideally positioned to respond to translocating microbial antigen.

METHODS

Duodenal biopsies, obtained from patients naive to cART, underwent trichrome staining and were examined for tissue growth factor-beta (TGF-β) expression. Combined immunostaining and second harmonic generation analysis were used to determine IMF activation and collagen deposition. Confocal microscopy was performed to examine IMF activation and Toll-like receptor (TLR)4 expression. Finally, primary IMF cultures were stimulated with lipopolysaccharide to demonstrate the expression of the inflammatory biomarkers.

RESULTS

The expression of the fibrosis-promoting molecule, TGF-β1, is significantly increased in duodenal biopsies from HIV patients naïve to cART, and negatively correlated with subsequent peripheral CD4(+) recovery. The increase in TGF-β1 coincided with an increase in collagen deposition in the duodenal mucosa in the tissue area adjacent to the IMFs. We also observed that IMFs expressed TLR4 and had an activated phenotype since they were positive for fibroblast activation protein. Finally, stimulation of IMFs from HIV patients with TLR4 resulted in significantly increased expression of profibrotic molecules, TGF-β1, and interleukin-6.

CONCLUSION

Our data support the hypothesis that activated IMFs may be among the major cells contributing to the profibrotic changes, and thus, the establishment and maintenance of systemic inflammation interfering with immune reconstitution in HIV patients.

Short communication: Plasmacytoid dendritic cells from HIV-1 Elite Controllers maintain a gut-homing phenotype associated with immune activation

Lentivirus infections are characterized by a dramatic loss of mucosal CD4(+) T cells, breakdown of the gut mucosa, and subsequent chronic immune activation. Residual immune activation persists even in patients controlling virus replication and remains a significant source of ongoing disease morbidities, but the causes are unclear. Plasmacytoid dendritic cells (pDCs), primary producers of interferon (IFN)-α, have been previously shown to be depleted from peripheral blood of HIV patients and simian immunodeficiency virus (SIV)-infected macaques, and most recently have been shown to accumulate in the gut mucosa. Although previous work has shown that pDC frequencies can be reduced in the circulation of HIV-1 Elite Controllers, it is unknown if gut-homing also occurs. In this new study we found that during progressive HIV-1 infection pDCs were depleted in peripheral blood compared to seronegative controls, and, correlating with plasma viremia, the remaining pDCs upregulated the gut-homing marker, α4β7. Even in HIV-1 Elite Controllers pDCs were significantly reduced in blood and α4β7 expression was still significantly upregulated compared to seronegative controls. Interestingly, pDC trafficking to the gut was associated with increased Ki67 and HLA-DR on circulating CD4(+) and CD8(+) T cells. Overall, these data suggest that gut trafficking of pDCs is independent of virus replication and could be mediated by alternative mechanisms, which in turn could contribute to residual immune activation in HIV-1 Elite Controllers.

Circulating biomarkers of immune activation distinguish viral suppression from nonsuppression in HAART-treated patients with advanced HIV-1 subtype C infection

Few studies have examined immune activation profiles in patients with advanced HIV-1 subtype C infection or assessed their potential to predict responsiveness to HAART. BioPlex, ELISA, and nephelometric procedures were used to measure plasma levels of inflammatory biomarkers in HIV-1 subtype C-infected patients sampled before and after 6 months of successful HAART (n = 20); in patients failing HAART (n = 30); and in uninfected controls (n = 8). Prior to HAART, CXCL9, CXCL10, β 2M, sTNF-R1, TGF- β 1, IFN- γ , IL-6, TNF, and sCD14 were significantly elevated in HIV-1-infected patients compared to controls (P < 0.01). All of these markers, with the exception of sTNF-R1, were also elevated in patients failing HAART (P < 0.05). The persistently elevated levels of CXCL9, CXCL10, and β 2M in patients failing therapy in the setting of a marked reduction in these markers in patients on successful HAART suggest that they may be useful not only to monitor immune activation during HAART, but also to distinguish between good and poor responders. In the case of sCD14 and TGF- β 1, the levels of these biomarkers remained persistently elevated despite HAART-induced virological suppression, a finding that is consistent with ongoing monocyte-macrophage activation, underscoring a potential role for adjuvant anti-inflammatory therapy.

Factors related to changes in CD4+ T-cell counts over time in patients living with HIV/AIDS: a multilevel analysis

Background

The measurement of CD4+ T-cell (CD4) counts is a strong predictor of progression to AIDS and a means of monitoring antiviral therapy (ART). The success or failure of controlling virus levels in untreated patients or those taking ART may be associated with treatment adherence, habits, correlated infections unrelated to HIV, cancer, immunosuppressive drugs; as well as socio-economic and psychosocial aspects and access to healthcare. The aim of the present study was to identify, using a multilevel model, the factors related to the variations of CD4 counts over time, in patients living with HIV.

Methodology

A cohort study was conducted with patients living with HIV, selected from July 2007 to December 2010. Patients were monitored from records of their first CD4 count after being diagnosed with HIV. A multilevel model with 3 levels of aggregation was applied to analyze the associations of predictor variables and the behavior of CD4 over time.

Principal Findings

A total of 1870 patients were enrolled. The mean number of CD4 at the beginning of the cohort was 393.1 cells/mm³, and there was a mean increase of 1.529 cells/mm³ per month. Patient's age, smoking, use of illicit drugs, hospital treatment, changing doctors and the use of ART, were factors that affected the kinetics of the CD4 count during the follow-up period.

Conclusion/Significance

The results of this study indicated increased levels of CD4 over time in a cohort of patients living with HIV/AIDS and identified factors that may influence this increase and are liable to intervention.

Immuno-virological discordance and the risk of non-AIDS and AIDS events in a large observational cohort of HIV-patients in Europe

BACKGROUND

The impact of immunosuppression despite virological suppression (immuno-virological discordance, ID) on the risk of developing fatal and non-fatal AIDS/non-AIDS events is unclear and remains to be elucidated.

METHODS

Patients in EuroSIDA starting at least 1 new antiretroviral drug with CD4<350 cells/µl and viral load (VL)>500 copies/mL were followed-up from the first day of VL< = 50 copies/ml until a new fatal/non-fatal non-AIDS/AIDS event. Considered non-AIDS events included non-AIDS malignancies, pancreatitis, severe liver disease with hepatic encephalopathy (>grade 3), cardio- and cerebrovascular events, and end-stage renal disease. Patients were classified over time according to whether current CD4 count was above (non-ID) or below (ID) baseline level. Relative rates (RR) of events were calculated for ID vs. non-ID using adjusted Poisson regression models.

RESULTS

2,913 patients contributed 11,491 person-years for the analysis of non-AIDS. 241 pre-specified non-AIDS events (including 84 deaths) and 89 AIDS events (including 10 deaths) occurred. The RR of developing pre-specified non-AIDS events for ID vs. non-ID was 1.96 (95% CI 1.37-2.81, p<0.001) in unadjusted analysis and 1.43 (0.94-2.17, p = 0.095) after controlling for current CD4 count. ID was not associated with the risk of AIDS events (aRR 0.76, 95% CI 0.41-1.38, p = 0.361).

CONCLUSION

Compared to CD4 responders, patients with immuno-virological discordance may be at increased risk of developing non-AIDS events. Further studies are warranted to establish whether in patients with ID, strategies to directly modify CD4 count response may be needed besides the use of ART.

Pathobiology of HIV/SIV-associated changes in secondary lymphoid tissues

Acquired immunodeficiency syndrome (AIDS) is principally a disease of lymphoid tissues (LTs), due to the fact that the main target cell of human immunodeficiency virus (HIV) is the CD4(+) T lymphocyte that primarily resides within organs of the immune system. The impact of HIV infection on secondary LTs, in particular lymph nodes, is critical to delineate, as these immune organs are the principal sites for initiating and facilitating immune responses and are critical for lymphocyte homeostatic maintenance and survival. The underlying structural elements of LTs, fibroblastic reticular cell (FRC) network, not only form the architectural framework for these organs, but also play in integral role in the production and storage of cytokines needed for T-cell survival. There is an interdependent relationship between the FRC stromal network and CD4(+) T lymphocytes for their survival and maintenance that is progressively disrupted during HIV disease. HIV infection results in profound pathological changes to LTs induced by persistent chronic immune activation and inflammation that leads to progressive collagen deposition and fibrosis disrupting and damaging the important FRC network. In this review, I focus on the process, mechanisms, and the implications of pathological damage to important secondary LTs, combining what we have learned from HIV-infected individuals as well as the invaluable knowledge gained from studies in non-human primate simian immunodeficiency virus infection models.

HIV-associated bacterial pneumonia

Community-acquired bacterial pneumonia (CAP) remains one of the most common opportunistic infections in patients who are infected with the human immunodeficiency virus (HIV). The risk of CAP increases as the CD4 cell count decreases. The common bacterial pathogens that cause CAP in HIV-infected persons are similar to those in HIV-uninfected individuals, with the pneumococcus being the most common pathogen. Prevention of CAP remains critical and necessitates a comprehensive approach addressing, among many other factors, cigarette smoking cessation strategies, antiretroviral therapy adherence, and immunization against those infections for which effective vaccinations are available.

Impact of xerostomia on oral health and quality of life among adults infected with HIV-1

The study investigated the impact of xerostomia on oral health and quality of life (QoL) among patients infected with human immunodeficiency virus (HIV) who were attending for routine HIV monitoring in Australia. This cross-sectional, self-administered questionnaire survey and oral screening (OS) included 100 subjects who were HIV positive. The OS was conducted by a dentist blinded to the subject's survey responses. Xerostomia was determined by asking the subjects a single question. Subjects with xerostomia were found to have increased caries activity and poorer QoL, especially in the psychological dimensions of the oral health impact profile. Age and duration of HIV infection were associated with xerostomia. Early diagnosis of xerostomia and intervention with preventive dental care would potentially reduce caries and improve QoL among patients infected with HIV-1. Ongoing chronic inflammation of salivary glands despite the beneficial effects of antiretroviral therapy may play a role in the etiology of xerostomia in patients infected with HIV and requires further study.

Alternative serotype adenovirus vaccine vectors elicit memory T cells with enhanced anamnestic capacity compared to Ad5 vectors

The failure of the adenovirus serotype 5 (Ad5) vector-based human immunodeficiency virus type 1 (HIV-1) vaccine in the STEP study has led to the development of adenovirus vectors derived from alternative serotypes, such as Ad26, Ad35, and Ad48. We have recently demonstrated that vaccines using alternative-serotype Ad vectors confer partial protection against stringent simian immunodeficiency virus (SIV) challenges in rhesus monkeys. However, phenotypic differences between the T cell responses elicited by Ad5 and those of alternative-serotype Ad vectors remain unexplored. Here, we report the magnitude, phenotype, functionality, and recall capacity of memory T cell responses elicited in mice by Ad5, Ad26, Ad35, and Ad48 vectors expressing lymphocytic choriomeningitis virus (LCMV) glycoprotein (GP). Our data demonstrate that memory T cells elicited by Ad5 vectors were high in magnitude but exhibited functional exhaustion and decreased anamnestic potential following secondary antigen challenge compared to Ad26, Ad35, and Ad48 vectors. These data suggest that vaccination with alternative-serotype Ad vectors offers substantial immunological advantages over Ad5 vectors, in addition to circumventing high baseline Ad5-specific neutralizing antibody titers.

Lymphoid tissue structure and HIV-1 infection: life or death for T cells

Secondary lymphoid tissue (LT) structure facilitates immune responses and maintains homeostasis of T cells through production of survival factors, such as interleukin (IL)-7 that is 'posted' on the stromal fibroblastic reticular cell (FRC) network on which T cells traffic. Here, we examine the pathological changes that occur in LTs during HIV and simian immunodeficiency virus (SIV) infection. Immune activation leads to collagen deposition and loss of the FRC network itself. This decreases access to IL-7 and reduces the major source of IL-7, both of which deplete naïve T cells to limit immune reconstitution with antiretroviral treatment. We discuss the implications of LT structure damage for the timing of antiretroviral therapy and consider the development of adjunctive antifibrotic agents to improve immune reconstitution in HIV infection.

Factors predicting discordant virological and immunological responses to antiretroviral therapy in HIV-1 clade C infected Zulu/Xhosa in South Africa

Factors predicting suboptimal CD4 cell recovery have been studied in HIV clade-B infected US and European populations. It is, however, uncertain to what extent these results are applicable to HIV clade-C infected African populations. Multivariate analysis using logistic regression and longitudinal analyses using mixed models were employed to assess the impact of age, gender, baseline CD4 cell count, hemoglobin, body mass index (BMI), tuberculosis and other opportunistic co-infections, and frequencies of regimen change on CD4 cell recovery at 12 and 30 months and on overtime change in CD4 cells among 442 virologically suppressed South Africans. Despite adequate virological response 37% (95% CI:32%–42%) and 83% (95% CI:79%–86%) of patients on antiretroviral therapy failed to restore CD4 cell counts ≥200 cells/mm³ after 12 and ≥500 cells/mm³ after 30 months, respectively, in this South African cohort. Critical risk factors for inadequate recovery were older age (p = 0.001) and nadir CD4 cell count at ART initiation (p<0.0001), while concurrent TB co-infection, BMI, baseline hemoglobin, gender and antiretroviral regimen were not significant risk factors. These data suggest that greater efforts are needed to identify and treat HAART-eligible patients prior to severe CD4 cell decline or achievement of advanced age.

Non-cirrhotic portal hypertension in HIV-infected individuals

Non-cirrhotic portal hypertension (NCPH) has been associated with didanosine (ddI) exposure. We aimed to determine the number of individuals with NCPH within our cohort and define their characteristics. We identified individuals within our cohort with NCPH and performed a retrospective case note review. Cumulative antiretroviral therapy (ART) use was calculated and a statistical analysis performed to compare exposure to the rest of the clinic cohort for the same time period. Where available, data was collated on FibroScan®, echocardiography and coagulation profile. Seventeen patients were identified. Upper gastrointestinal bleeding was the most common presenting feature. Liver biopsy showed mild portal or periportal fibrosis in 13 (81%) and four with features of nodular regenerative hyperplasia. There was significantly greater exposure to ddl in this group (59.5 months) compared to the rest of the HIV cohort (21.1 months) P = <0.001. Eleven subjects has a liver elastography performed, six (55%) had a result greater than 9.6 kPa (consistent with greater than F2 disease by Metavir scoring). Echocardiography was performed in seven patients: four met criteria for pulmonary hypertension. This is consistent with other cohorts demonstrating an association between the didanosine exposure and NCPH. Our data also suggest an increased risk of pulmonary hypertension.

Interferon successfully inhibited refractory cytomegalovirus infection and resulted in CD4+ T-cells increase in a patient with AIDS

We report on a young male HIV-positive patient with cytomegalovirus (CMV) retinitis who received HAART and ganciclovir but could not gain immune restoration. One and a half years later, his CMV reoccurred. He was treated again with ganciclovir treatment combined with foscarnet treatment but failed. Finally, he was treated with recombinant human interferon alpha-2b (IFN-α2b) alone and acquired sustained inhibition to CMV. His CD4+ T-cell count increased to 186 cell/mm3 and gained partial immune restoration. Retinitis progression has stopped.

Interruptions of cART limits CD4 T-cell recovery and increases the risk for opportunistic complications and death

BACKGROUND

A major goal of antiretroviral therapy (ART) for HIV-1-infected persons is the recovery of CD4 T lymphocytes, resulting in thorough protection against opportunistic complications. Interruptions of ART are still frequent. The long-term effect on CD4 T-cell recovery and clinical events remains unknown.

METHODS

Immunological and clinical endpoints were evaluated in 2491 participants of the Swiss HIV Cohort Study initiating ART during a mean follow-up of 7.1 years. Data were analysed in persons with treatment interruptions (n = 1271; group A), continuous ART, but intermittent HIV-1 RNA at least 1000 copies/ml (n = 469; group B) and continuous ART and HIV-1 RNA constantly less than 1000 copies/ml (n = 751; group C). Risk factors for low CD4 T-cell counts and clinical events were analysed using Cox proportional hazards models.

RESULTS

In groups A-C, CD4 T lymphocytes increased to a median of 427, 525 and 645 cells/μl at 8 years. In group A, 63.0 and 37.2% reached above 350 and 500 CD4 T cells/μl, whereas in group B 76.3 and 55.8% and in group C 87.3 and 68.0% reached these thresholds (P < 0.001). CD4 T-cell recovery directly depended on the cumulative duration of treatment interruptions. In addition, participants of group A had more Centers for Disease Control and Prevention B/C events, resulting in an increased risk of death. Major risk factors for not reaching CD4 T cells above 500 cells/μl included lower baseline CD4 T-cell count, higher age and hepatitis C virus co-infection.

CONCLUSION

In persons receiving continuous ART larger CD4 T-cell recovery and a reduced risk for opportunistic complications and death was observed. CD4 T-cell recovery was smaller in persons with treatment interruptions more than 6 months.

A CD4+ cell count <200 cells per cubic millimeter at 2 years after initiation of combination antiretroviral therapy is associated with increased mortality in HIV-infected individuals with viral suppression

OBJECTIVE

To determine the long-term impact of immunologic discordance (viral load <50 copies/mL and CD4+ count <=200 cells/mm3) in antiretroviral-naive patients initiating combination antiretroviral therapy (cART).

METHODS

Our analysis included antiretroviral-naive individuals from a population-based Canadian Observational Cohort that initiated cART after January 1, 2000, and achieved virologic suppression. Multivariable Cox proportional hazards regression was used to examine the association between 1-year and 2-year immunologic discordance and time to death from all-causes. Correlates of immunologic discordance were assessed with logistic regression.

RESULTS

Immunologic discordance was observed in 19.9% (404 of 2028) and 10.2% (176 of 1721) of individuals at 1 and 2 years after cART initiation, respectively. Two-year immunologic discordance was associated with an increased risk of death [adjusted hazard ratio = 2.69; 95% confidence interval (CI): 1.26 to 5.78]. One-year immunologic discordance was not associated with death (adjusted hazard ratio = 1.12; 95% CI: 0.54 to 2.30). Two-year immunologic discordance was associated with older age (aOR per decade = 1.23; 95% CI: 1.03 to 1.48), male gender (aOR = 1.86; 95% CI: 1.09 to 3.16), injection drug use (aOR = 2.75; 95% CI: 1.81 to 4.17), and lower baseline CD4+ count (aOR per 100 cells = 0.24; 95% CI: 0.19 to 0.31) and viral load (aOR per log10 copies/mL = 0.46; 95% CI: 0.33 to 0.65).

CONCLUSIONS

Immunologic discordance after 2 years of cART in antiretroviral-naive individuals was significantly associated with an increased risk of mortality.

Factors associated with collagen deposition in lymphoid tissue in long-term treated HIV-infected patients

OBJECTIVE

The factors associated with fibrosis in lymphoid tissue in long-term treated HIV-infected patients and their correlation with immune reconstitution were assessed.

METHODS

Tonsillar biopsies were performed in seven antiretroviral-naive patients and 29 successfully treated patients (median time on treatment, 61 months). Twenty patients received protease inhibitors-sparing regimens and nine protease inhibitor-containing regimens. Five tonsillar resections of HIV-negative individuals were used as controls. Lymphoid tissue architecture, collagen deposition (fibrosis) and the mean interfollicular CD4(+) cell count per mum were assessed.

RESULTS

Naive and long-term treated HIV-infected patients had a higher proportion of fibrosis than did HIV-uninfected persons (P < 0.001). Patients with greater collagen deposition showed lower levels of CD4 cells in lymphoid tissue (P = 0.03) and smaller increase in peripheral CD4(+) T cells (r = -0.40, P = 0.05). The factors independently associated with fibrosis in lymphoid tissue were age (P < 0.0001), treated patients with detectable lymphoid tissue viral load when compared with patients with undetectable lymphoid tissue viral load (median 5 vs. 12%, respectively, P = 0.017) and patients receiving a protease inhibitor-sparing vs. a protease inhibitor-containing regimen (median 8 vs. 2.5%, respectively, P = 0.04).

CONCLUSION

Fibrosis in lymphoid tissue was associated with a poor reconstitution of CD4(+) T cells and long-term antiretroviral therapy did not reverse this abnormality. HIV infection, older age, a detectable level of lymphoid tissue viral load in treated patients and protease inhibitor-sparing regimens seem to favour fibrosis in lymphoid tissue.

Role of the CD4 count in HIV management

As a result of successful antiretroviral treatment over the last 20 years, HIV has become more of a chronic disease for practitioners to manage, requiring careful, but routine, clinical monitoring. Laboratory markers, such as the HIV-1 RNA viral load and CD4 cell count, are regularly used for patient management in addition to predicting disease progression and/or treatment outcomes. The HIV viral load is considered to be the gold standard for evaluating treatment success, although it is often limited by the cost. Furthermore, in certain cases, there is a mismatch between an undetectable viral load (<50 copies/ml) and the absence of immune reconstitution, which can be confusing to both the treatment provider and patient. In this review, the utility of the CD4 count as a predictor for HIV disease progression in patients not on therapy is evaluated, as well as a method for monitoring a patient’s response to therapy. Its use in predicting immune reconstitution in patients initiating antiretrovirals is also identified. We hope to aid the clinician by examining the most recent literature and discussing the added value of the CD4 count in the management of a person with HIV infection.