The Era of DAAs: Assessing the Patients' Characteristics, Clinical Impact, and Emergence of Comorbidities in HIV/HCV-Coinfected versus HIV-Infected Individuals.

Objective: To determine whether HIV-infected individuals versus individuals with HIV/HCV coinfection, in the era of interferon-free therapies, exhibit an increased incidence of comorbidities and non-AIDS-related events. Methods: A retrospective analysis was conducted by collecting data from clinical records of Spanish patients at a tertiary hospital involving HIV/HCV-coinfected and HIV-infected patients, all with effectively controlled HIV. Coinfected patients underwent HCV clearance using direct-acting antivirals (DAAs) and had no history of interferon treatment. The incidences of hypertension, diabetes mellitus, cardiovascular disease, kidney disease, liver disease, non-AIDS cancer, and death were compared between the groups. Multivariate adjustments for all factors potentially impacting outcomes were used to assess the risk of clinical event onset. Propensity score (PS) analyses were also conducted to support the multivariate model results. Results: Data were available from 229 HIV/HCV-coinfected patients and 229 HIV-infected patients. Both cohorts were comparable in terms of age, gender distribution, follow-up, and HIV-related characteristics. Multivariate models and PS showed that previous exposure to HCV was not associated with the onset of any clinical events studied. Significant differences between HIV/HCV-coinfected and HIV-infected were not found for survival according to the log-rank test (p = 0.402). Conclusions: Successful HCV elimination using DAAs improved the outlook regarding comorbidities and survival across HIV/HCV-coinfected cohorts. Early HCV detection and DAA therapy could enhance clinical results. These findings provide an optimistic perspective for those living with HIV/HCV coinfection and underscore the importance of continuing efforts toward early detection and DAA treatment initiation.

T Cell Homeostasis Disturbances in a Cohort of Long-Term Elite Controllers of HIV Infection.

Elite controllers (ECs) are people living with HIV (PLWH) able to control HIV replication without antiretroviral therapy and have been proposed as a model of a functional HIV cure. Much evidence suggests that this spontaneous control of HIV has a cost in terms of T cell homeostasis alterations. We performed a deep phenotypic study to obtain insight into T cell homeostasis disturbances in ECs maintaining long-term virologic and immunologic control of HIV (long-term elite controllers; LTECs). Forty-seven PLWH were included: 22 LTECs, 15 non-controllers under successful antiretroviral therapy (onART), and 10 non-controllers not receiving ART (offART). Twenty uninfected participants (UCs) were included as a reference. T cell homeostasis was analyzed by spectral flow cytometry and data were analyzed using dimensionality reduction and clustering using R software v3.3.2. Dimensionality reduction and clustering yielded 57 and 54 different CD4 and CD8 T cell clusters, respectively. The offART group showed the highest perturbation of T cell homeostasis, with 18 CD4 clusters and 15 CD8 clusters significantly different from those of UCs. Most of these alterations were reverted in the onART group. Interestingly, LTECs presented several disturbances of T cell homeostasis with 15 CD4 clusters and 13 CD8 clusters different from UC. Moreover, there was a specific profile of T cell homeostasis alterations associated with LTECs, characterized by increases in clusters of naïve T cells, increases in clusters of non-senescent effector CD8 cells, and increases in clusters of central memory CD4 cells. These results demonstrate that, compared to ART-mediated control of HIV, the spontaneous control of HIV is associated with several disturbances in CD4 and CD8 T cell homeostasis. These alterations could be related to the existence of a potent and efficient virus-specific T cell response, and to the ability to halt disease progression by maintaining an adequate pool of CD4 T cells.

A specific natural killer cells phenotypic signature associated to long term elite control of HIV infection.

Elite controllers (ECs) are an exceptional group of people living with HIV (PLWH) that control HIV replication without therapy. Among the mechanisms involved in this ability, natural killer (NK)-cells have recently gained much attention. We performed an in-deep phenotypic analysis of NK-cells to search for surrogate markers associated with the long term spontaneous control of HIV. Forty-seven PLWH (22 long-term EC [PLWH-long-term elite controllers (LTECs)], 15 noncontrollers receiving antiretroviral treatment [ART] [PLWH-onART], and 10 noncontrollers cART-naïve [PLWH-offART]), and 20 uninfected controls were included. NK-cells homeostasis was analyzed by spectral flow cytometry using a panel of 15 different markers. Data were analyzed using FCSExpress and R software for unsupervised multidimensional analysis. Six different subsets of NK-cells were defined on the basis of CD16 and CD56 expression, and the multidimensional analysis revealed the existence of 68 different NK-cells clusters based on the expression levels of the 15 different markers. PLWH-offART presented the highest disturbance of NK-cells homeostasis and this was not completely restored by long-term ART. Interestingly, long term spontaneous control of HIV (PLWH-LTEC group) was associated with a specific profile of NK-cells homeostasis disturbance, characterized by an increase of CD16dimCD56dim subset when compared to uninfected controls (UC) group and also to offART and onART groups (p < 0.0001 for the global comparison), an increase of clusters C16 and C26 when compared to UC and onART groups (adjusted p-value < 0.05 for both comparisons), and a decrease of clusters C10 and C20 when compared to all the other groups (adjusted p-value < 0.05 for all comparisons). These findings may provide clues to elucidate markers of innate immunity with a relevant role in the long-term control of HIV.

Immune checkpoint inhibitors as potential therapy for reverting T-cell exhaustion and reverting HIV latency in people living with HIV.

The immune system of people living with HIV (PLWH) is persistently exposed to antigens leading to systemic inflammation despite combination antiretroviral treatment (cART). This inflammatory milieu promotes T-cell activation and exhaustion. Furthermore, it produces diminished effector functions including loss of cytokine production, cytotoxicity, and proliferation, leading to disease progression. Exhausted T cells show overexpression of immune checkpoint molecules (ICs) on the cell surface, including programmed cell death protein 1 (PD-1), cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4), T-cell immunoglobulin and mucin-domain containing-3 (TIM-3), T-cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domain (TIGIT), and lymphocyte activation gene-3 (LAG-3). The ICs also play a crucial role in T-cell exhaustion by reducing the immune response to cancer antigens. Immunotherapy based on immune checkpoint inhibitors (ICIs) has changed the management of a diversity of cancers. Additionally, the interest in exploring this approach in the setting of HIV infection has increased, including AIDS-defining cancers and non-AIDS-defining cancers in PLWH. To date, research on this topic suggests that ICI-based therapies in PLWH could be a safe and effective approach. In this review, we provide an overview of the current literature on the potential role of ICI-based immunotherapy not only in cancer remission in PLWH but also as a therapeutic intervention to restore immune response against HIV, revert HIV latency, and attain a functional cure for HIV infection.

Factors involved in resistance to human immunodeficiency virus infection / Factores que influyen en la resistencia a la infección por el virus de la inmunodeficiencia humana

Existen individuos expuestos repetidamente al virus de la inmunodeficiencia humana (VIH) sin evidencia clínica ni serológica de infección; se denominan expuestos seronegativos (ESN). Se han identificado factores del huésped genéticos e inmunológicos que confieren una baja susceptibilidad a la infección por VIH en ESN. Los factores genéticos están relacionados con genes que codifican los receptores de quimiocinas y sus ligandos naturales, así como los genes del complejo mayor de histocompatibilidad. Los factores inmunológicos se refieren tanto a la inmunidad innata como adaptativa. El estudio de los ESN proporciona una oportunidad única para identificar los posibles mecanismos del huésped implicados en un control eficaz de la infección vírica. Puede ser de gran interés para el diseño de estrategias preventivas o inmuno-terapéuticas, incluyendo vacunas (AU)

Repeated exposure to human immunodeficiency virus (HIV) is not always associated with infection and a subset of individuals remains persistently as HIV-seronegative despite multiple episodes of HIV exposure. These individuals are called HIV-exposed seronegatives (ESN). Several genetic and immunological factors have been involved in this resistance to HIV acquisition. Genetic factors have been linked to genes encoding chemokine receptors and their natural ligands as well as genes of the major histocompatibility complex. Immunological factors include both innate and adaptive immunity. The study of ESN provides a unique opportunity to unveil the mechanisms of natural protection against viral infection. Their better understanding may lead to novel preventive and immune-therapeutic approaches, including vaccines (AU)

Respuesta inmunitaria celular adaptativa frente a la infección por el virus de la hepatitis C / Adaptive cell immune response against the hepatitis C virus infection

El virus de la hepatitis C (VHC) infecta alrededor de 175 millones de personas en el mundo y es una de las principales causas de enfermedad hepática crónica. Menos de una tercera parte de las personas expuestas controlan el virus espontáneamente después de la infección aguda, mientras que el resto evoluciona a la cronicidad. La resolución de la infección se ha asociado al componente celular de la respuesta inmunitaria del huésped. No se conoce bien qué distingue una respuesta inmunitaria celular exitosa frente al VHC. Una interpretación integral de los diversos hallazgos experimentales permite una mejor comprensión del porqué del fracaso inmunitario en la infección crónica por el VHC

Hepatitis C virus (HCV) infects around 175 million people worldwide and is one of the leading causes of chronic liver disease. Less than one third of patients infected with HCV are able to spontaneously clear the virus during acute infection, while most patients evolve to chronic infection. Control of viral replication has been associated to the cellular component of the host immune response. It is not fully understood what distinguish a successful cellular immune response. An integral interpretation of the numerous experimental findings may allow a better understanding of the immune mechanisms involved in the inability of the immune system to successfully control chronic HCV infection