CD4 recovery is associated with genetic variation in IFNγ and IL19 genes

Advances in Mechanism of HIV-1 Immune Reconstitution Failure: Understanding Lymphocyte Subpopulations and Interventions for Immunological Nonresponders

In individuals diagnosed with AIDS, the primary method of sustained suppression of HIV-1 replication is antiretroviral therapy, which systematically increases CD4+ T cell levels and restores immune function. However, there is still a subset of 10-40% of people living with HIV who not only fail to reach normal CD4+ T cell counts but also experience severe immune dysfunction. These individuals are referred to as immunological nonresponders (INRs). INRs have a higher susceptibility to opportunistic infections and non-AIDS-related illnesses, resulting in increased morbidity and mortality rates. Therefore, it is crucial to gain new insights into the primary mechanisms of immune reconstitution failure to enable early and effective treatment for individuals at risk. This review provides an overview of the dynamics of key lymphocyte subpopulations, the main molecular mechanisms of INRs, clinical diagnosis, and intervention strategies during immune reconstitution failure, primarily from a multiomics perspective.

Incomplete immune reconstitution and its predictors in people living with HIV in Wuhan, China

OBJECTIVE

This study aimed to build and validate a nomogram model to predict the risk of incomplete immune reconstitution in people living with HIV (PLWH).

METHODS

Totally 3783 individuals with a confirmed diagnosis of HIV/AIDS were included. A predictive model was developed based on a retrospective set (N = 2678) and was validated using the remaining cases (N = 1105). Univariate and multivariate logistic regression analyses were performed to determine valuable predictors among the collected clinical and laboratory variables. The predictive model is presented in the form of a nomogram, which is internally and externally validated with two independent datasets. The discrimination of nomograms was assessed by calculating the area under the curve (AUC). Besides, calibration curve and decision curve (DCA) analyses were performed in the training and validation sets.

RESULTS

The final model comprised 5 predictors, including baseline CD4, age at ART initiation, BMI, HZ and TBIL. The AUC of the nomogram model was 0.902, 0.926, 0.851 in the training cohort, internal validation and external cohorts. The calibration accuracy and diagnostic performance were satisfactory in both the training and validation sets.

CONCLUSIONS

This predictive model based on a retrospective study was externally validated using 5 readily available clinical indicators. It showed high performance in predicting the risk of incomplete immune reconstitution in people living with HIV.

Multi-omics in HIV: searching insights to understand immunological non-response in PLHIV

Antiretroviral therapy (ART) induces persistent suppression of HIV-1 replication and gradual recovery of T-cell counts, and consequently, morbidity and mortality from HIV-related illnesses have been significantly reduced. However, in approximately 30% of people living with HIV (PLHIV) on ART, CD4+ T-cell counts fail to normalize despite ART and complete suppression of HIV viral load, resulting in severe immune dysfunction, which may represent an increased risk of clinical progression to AIDS and non-AIDS events as well as increased mortality. These patients are referred to as "immune inadequate responders", "immunodiscordant responders" or "immune nonresponders (INR)". The molecular mechanisms underlying poor CD4+ T-cell recovery are still unclear. In this sense, the use of omics sciences has shed light on possible factors involved in the activity and metabolic dysregulation of immune cells during the failure of CD4+ T-cell recovery in INR. Moreover, identification of key molecules by omics approaches allows for the proposal of potential biomarkers or therapeutic targets to improve CD4+ T-cell recovery and the quality of life of these patients. Hence, this review aimed to summarize the information obtained through different omics concerning the molecular factors and pathways associated with the INR phenotype to better understand the complexity of this immunological status in HIV infection.

Recent advances in poor HIV immune reconstitution: what will the future look like?

Combination antiretroviral therapy has demonstrated proved effectiveness in suppressing viral replication and significantly recovering CD4+ T cell count in HIV type-1 (HIV-1)-infected patients, contributing to a dramatic reduction in AIDS morbidity and mortality. However, the factors affecting immune reconstitution are extremely complex. Demographic factors, co-infection, baseline CD4 cell level, abnormal immune activation, and cytokine dysregulation may all affect immune reconstitution. According to report, 10-40% of HIV-1-infected patients fail to restore the normalization of CD4+ T cell count and function. They are referred to as immunological non-responders (INRs) who fail to achieve complete immune reconstitution and have a higher mortality rate and higher risk of developing other non-AIDS diseases compared with those who achieve complete immune reconstitution. Heretofore, the mechanisms underlying incomplete immune reconstitution in HIV remain elusive, and INRs are not effectively treated or mitigated. This review discusses the recent progress of mechanisms and factors responsible for incomplete immune reconstitution in AIDS and summarizes the corresponding therapeutic strategies according to different mechanisms to improve the individual therapy.

Increased Microbial Translocation is a Prognostic Biomarker of Different Immune Responses to ART in People Living with HIV

Background

Microbial translocation (MT) is a characteristic of human immunodeficiency virus (HIV) infection. Whether MT is also a biomarker of different immune responses to antiretroviral therapy (ART) received by people living with HIV (PLWH) is not known.

Methods

We examined the presence of MT in a cohort of 33 HIV-infected immunological responders (IRs) and 28 immunological non-responders (INRs) (≥500 and <200 cluster of differentiation (CD)4+ T-cell counts/µL after 2 years of HIV-1 suppression, respectively) with no comorbidities. Plasma samples were used to measure the circulating levels of MT markers. All enrolled study participants had received 2 years of viral-suppression therapy.

Results

Levels of lipopolysaccharide (P = 0.0185), LPS-binding protein (P < 0.0001), soluble-CD14 (P < 0.0001), and endogenous endotoxin-core antibody (P < 0.0001) at baseline were significantly higher in INRs than in IRs and were associated with an increased risk of an immunological non-response, whereas the level of intestinal fatty acid-binding protein did not show this association. Analysis of receiver operating characteristic (ROC) curves demonstrated the utility of these individual microbial markers in discriminating INRs after ART in people living with HIV with high sensitivity, specificity, and area under the ROC curve.

Conclusion

INRs in HIV infection are characterized by increased MT at baseline. These markers could be used as a rapid prognostic tool for predicting immune responses in people infected with the HIV.

DBP rs7041 and DHCR7 rs3829251 are Linked to CD4+ Recovery in HIV Patients on Antiretroviral Therapy

Background: The lack of the recovery of CD4⁺ T-cells (CD4⁺ recovery) among immunodeficiency virus (HIV)-infected patients on antiretroviral therapy (ART) is not well known. We aimed to analyze the association between single nucleotide polymorphisms (SNPs) underlying vitamin D metabolism and the CD4⁺ recovery in naïve HIV-infected patients who started ART with low baseline CD4⁺.

Methods: We conducted a retrospective study in 411 naïve individuals with plasma HIV load >200 copies/mL and CD4⁺ <200 cells/mm³. During 24 months of follow-up, all patients had plasma HIV load <50 copies/mL. DNA genotyping was performed using the Sequenom MassARRAY platform. The outcome variable was the change in CD4⁺ during the study.

Results: CD4⁺ recovery was higher in patients carrying DBP rs7041 AA genotype (AA versus CC/AC) and DHCR7 rs3829251 AA genotype (AA versus GG/AG) (p-value < 0.05). DBP rs7041 AA genotype was linked to increase in CD4⁺ (adjusted arithmetic mean ratio (aAMR) = 1.22; q-value = 0.011), increase in CD4⁺ ≥P75th [adjusted odds ratio (aOR) = 2.31; q-value = 0.005], slope of CD4⁺ recovery (aAMR = 1.25; q-value = 0.008), slope of CD4⁺ recovery ≥ P75th (aOR = 2.55; q-value = 0.005) and achievement of CD4⁺ ≥500 cells/mm³ (aOR = 1.89; q-value = 0.023). Besides, DHCR7 rs3829251 AA genotype was related to increase in CD4⁺ (aAMR = 1.43; q-value = 0.031), increase in CD4⁺ ≥P75th (aOR = 3.92; q-value = 0.030), slope of CD4⁺ recovery (aAMR = 1.40; q-value = 0.036), slope of CD4⁺ recovery ≥ P75th (aOR = 3.42; q-value = 0.031) and achievement of CD4⁺ ≥500 cells/mm³ (aOR = 5.68; q-value = 0.015).

Conclusion: In summary, DHCR7 rs3829251 and DBP rs7041 polymorphisms were associated with CD4⁺ recovery in HIV-infected patients who started cART with low CD4⁺ T-cell counts.

Incomplete immune reconstitution in HIV/AIDS patients on antiretroviral therapy: Challenges of immunological non-responders

The morbidity and mortality of HIV type-1 (HIV-1)-related diseases were dramatically diminished by the grounds of the introduction of potent antiretroviral therapy, which induces persistent suppression of HIV-1 replication and gradual recovery of CD4⁺ T-cell counts. However, ∼10-40% of HIV-1-infected individuals fail to achieve normalization of CD4⁺ T-cell counts despite persistent virological suppression. These patients are referred to as "inadequate immunological responders," "immunodiscordant responders," or "immunological non-responders (INRs)" who show severe immunological dysfunction. Indeed, INRs are at an increased risk of clinical progression to AIDS and non-AIDS events and present higher rates of mortality than HIV-1-infected individuals with adequate immune reconstitution. To date, the underlying mechanism of incomplete immune reconstitution in HIV-1-infected patients has not been fully elucidated. In light of this limitation, it is of substantial practical significance to deeply understand the mechanism of immune reconstitution and design effective individualized treatment strategies. Therefore, in this review, we aim to highlight the mechanism and risk factors of incomplete immune reconstitution and strategies to intervene.