Neuroimmunology of CNS HIV Infection: A Narrative Review

Cerebrospinal Fluid and Peripheral Blood Lymphomonocyte Single-Cell Transcriptomics in a Subject with Multiple Sclerosis Acutely Infected with HIV

Signatures of neurodegeneration in clinical samples from a subject with multiple sclerosis (MS) acutely infected with HIV were investigated with single-cell transcriptomics using 10X Chromium technology. Sequencing was carried out on NovaSeq-TM, and the analysis was performed with Cell Ranger software (v 7.1.0) associated with a specifically established bioinformatic pipeline. A total of 1446 single-cell transcriptomes in cerebrospinal fluid (CSF) and 4647 in peripheral blood mononuclear cells (PBMCs) were obtained. In the CSF, many T-cell lymphocytes with an enriched amount of plasma cells and plasmacytoid dendritic (pDC) cells, as compared to the PBMCs, were detected. An unsupervised cluster analysis, putting together our patient transcriptomes with those of a publicly available MS scRNA-seq dataset, showed up-regulated microglial neurodegenerative gene expression in four clusters, two of which included our subject's transcriptomes. A few HIV-1 transcripts were found only in the CD4 central memory T-cells of the CSF compartment, mapping to the gag-pol, vpu, and env regions. Our data, which describe the signs of neurodegenerative gene expression in a very peculiar clinical situation, did not distinguish the cause between multiple sclerosis and HIV infection, but they can give a glimpse of the high degree of resolution that may be obtained by the single-cell transcriptomic approach.

Relationship between Stress and Neuroimmunological Responses and Health Literacy in Newly Diagnosed HIV-Infected Patients: An Exploratory Study

Objectives

We aimed to study self-rated health and psycho-neuroimmunological responses during the initial 6 months after testing positive for human immunodeficiency virus (HIV) and its relationship to health literacy, that is, the ability to take in and understand information about one's illness. Health literacy plays a critical role in patients' ability to adhere to antiretroviral treatment (ART). However, there is a lack of studies on the possible impact of HIV-induced proinflammatory processes on health literacy.

Methods

Twelve patients with newly diagnosed HIV attending an urban Ryan White-funded HIV clinic responded to a questionnaire and had blood samples drawn at baseline (first visit) and after 1, 3, and 6 months, respectively. The questionnaire measured stress, depression, and health literacy. Blood was analyzed for HIV RNA plasma viral load, CD4 cell count, pro- and antistress, and inflammatory markers.

Results

Complete data for the entire 4 collection periods were available for nine patients. Over the 6-month period, mean viral load decreased from 353,714.83 (standard deviation 870,334.61) to 35.89 (14.04) copies/mL (p < 0.001). CD4 cell count increased from 321.08 (167.96) to 592.44 (300.06) cells/mm3 (p < 0.001). Self-rated stress decreased from a baseline mean of 7.33 (2.29) to 3.56 (3.21), on a 0-10 visual analogue scale, at the 6-month follow-up (p < 0.01). C-reactive protein (CRP) decreased from 5757.05 (3146.86) to 2360.84 (2277.33) ng/mL (p < 0.05). Mean health literacy score at baseline was 17.67 (3.50; scale range 0-20) and did not change during the follow-up period. However, increased stress and decreased CRP (p = 0.05) during the 6-month follow-up predicted higher health literacy scores at 6 months.

Conclusion

Both stress and proinflammatory processes in newly diagnosed HIV-infected patients might adversely impact patients' health literacy and thus their capacity to align with treatment guidance.

Unveiling the Impact of Human Herpesviruses-Associated on CNS Infections: An Observational Study

Human Herpesviruses (HHVs) play a significant role in neurological diseases such as encephalitis and meningitis, adding significant morbidity. This study aims to retrospectively analyze the effect of HHVs on patients with neurological symptoms, focusing on the Herpesviridae family's contributions to central nervous system (CNS) infections.

METHODS

This retrospective cohort study included 895 patients suspected of viral CNS infections, utilizing molecular diagnosis via qPCR to identify HHVs in cerebrospinal fluid (CSF) samples. This was conducted at a reference tertiary care hospital for infectious diseases in the western Brazilian Amazon from January 2015 to December 2022, focusing on the Herpesviridae family's clinical repercussions and of Cytomegalovirus in CNS infections.

RESULTS

The findings revealed that 7.5% of the analyzed samples tested positive for HHVs, with Human Cytomegalovirus (HCMV) and Epstein-Barr Virus (EBV) being the most prevalent. A significant association was found between HHVs and neurological diseases such as encephalitis and meningitis, especially among people living with HIV/AIDS (PLWHA), highlighting the opportunistic nature of these viruses. The study underscores the critical role of CSF analysis in diagnosing CNS infections and the complexity of managing these infections in HIV patients due to their immunocompromised status.

CONCLUSIONS

The results emphasize the need for comprehensive diagnostic approaches and tailored treatment strategies for CNS infections in immunocompromised individuals. The study calls for ongoing research and advancements in clinical practice to improve patient outcomes facing CNS infections, particularly those caused by HHVs.

Blood-borne viruses and neurological manifestations: An overview

Infections caused by blood-borne viruses, such as human immunodeficiency virus (HIV), human T-lymphotropic virus (HTLV), hepatitis C virus (HCV), and hepatitis B virus (HBV), are systemic diseases that can lead to a wide range of pathological manifestations. Besides causing severe immune and hepatic disorders, these viral pathogens can also induce neurological dysfunctions via both direct and indirect mechanisms. Neurological dysfunctions are one of the most common manifestations caused by these viruses that can also serve as indicators of their infection, impacting the clinical presentation of the disease. The main neurological manifestations of these blood-borne viral pathogens consist of several central and peripheral nervous system (CNS and PNS, respectively) dysfunctions. The most common neurological manifestations of HIV, HTLV, HCV, and HBV include HIV-associated peripheral neuropathy (PN), HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), and HCV-/HBV-associated PN, respectively. Nonetheless, patients infected with these viruses may experience other neurological disorders, either associated with these conditions or manifesting in isolation, which can often go unnoticed or undiagnosed by physicians. The present review aims to provide an overview of the latest evidence on the relationship between blood-borne viruses and neurological disorders to highlight neurological conditions that may be somewhat overlooked by mainstream literature and physicians.

White and Gray Matter Changes are Associated With Neurocognitive Decline in HIV Infection

OBJECTIVE

To investigate the relationship between neurocognitive deficits and structural changes on brain magnetic resonance imaging in people living with HIV (PLWH) with good virological control on combination antiretroviral therapy, compared with socioeconomically matched control participants recruited from the same communities.

METHODS

Brain magnetic resonance imaging scans, and clinical and neuropsychological data were obtained from virologically controlled PLWH (viral load of <50 c/mL and at least 1 year of combination antiretroviral therapy) and socioeconomically matched control participants. Magnetic resonance imaging was carried out on 3 T scanner with 8-channel head coils and segmented using Classification using Derivative-based Features. Multiple regression analysis was performed to examine the association between brain volume and various clinical and neuropsychiatric parameters adjusting for age, race, and sex. To evaluate longitudinal changes in brain volumes, a random coefficient model was used to evaluate the changes over time (age) adjusting for sex and race.

RESULTS

The cross-sectional study included 164 PLWH and 51 controls, and the longitudinal study included 68 PLWH and 20 controls with 2 or more visits (mean 2.2 years, range 0.8-5.1 years). Gray matter (GM) atrophy rate was significantly higher in PLWH compared with control participants, and importantly, the GM and global atrophy was associated with the various neuropsychological domain scores. Higher volume of white matter hyperintensities were associated with increased atherosclerotic cardiovascular disease risk score, and decreased executive functioning and memory domain scores in PLWH.

INTERPRETATION

These findings suggest ongoing neurological damage even in virologically controlled participants, with significant implications for clinical management of PLWH. ANN NEUROL 2024;95:941-950.