Outcome markers of ART-treated HIV+ patients with early stage Kaposi's sarcoma

Antibody profiling and predictive modeling discriminate between Kaposi sarcoma and asymptomatic KSHV infection

Protein-level immunodominance patterns against Kaposi sarcoma-associated herpesvirus (KSHV), the aetiologic agent of Kaposi sarcoma (KS), have been revealed from serological probing of whole protein arrays, however, the epitopes that underlie these patterns have not been defined. We recently demonstrated the utility of phage display in high-resolution linear epitope mapping of the KSHV latency-associated nuclear antigen (LANA/ORF73). Here, a VirScan phage immunoprecipitation and sequencing approach, employing a library of 1,988 KSHV proteome-derived peptides, was used to quantify the breadth and magnitude of responses of 59 sub-Saharan African KS patients and 22 KSHV-infected asymptomatic individuals (ASY), and ultimately to support an application of machine-learning-based predictive modeling using the peptide-level responses. Comparing anti-KSHV antibody repertoire revealed that magnitude, not breadth, increased in KS. The most targeted epitopes in both KS and ASY were in the immunodominant proteins, notably, K8.129-56 and ORF65140-168, in addition to LANA. Finally, using unbiased machine-learning-based predictive models, reactivity to a subset of 25 discriminative peptides was demonstrated to successfully classify KS patients from asymptomatic individuals. Our study provides the highest resolution mapping of antigenicity across the entire KSHV proteome to date, which is vital to discern mechanisms of viral pathogenesis, to define prognostic biomarkers, and to design effective vaccine and therapeutic strategies. Future studies will investigate the diagnostic, prognostic, and therapeutic potential of the 25 discriminative peptides.

Evaluation of human herpesvirus-8 viremia and antibody positivity in patients with HIV infection with human herpesvirus-8-related diseases

Human herpesvirus-8 (HHV-8) viremia is associated with refractory conditions in patients infected with HIV-1. Therefore, we evaluated the factors related to plasma HHV-8-DNA. Participants included patients infected with HIV-1 who visited our hospital. Plasma HHV-8-DNA levels were measured using real-time polymerase chain reaction, and anti-HHV-8 antibodies were assessed through enzyme immunoassays using multiple antigens (K8.1, ORF59, ORF65, and LANA). Factors related to plasma HHV-8-DNA were examined using Fisher's exact test or Mann-Whitney U test. The study involved 36 patients infected with HIV-1, of whom 19 were histologically diagnosed with Kaposi's sarcoma (KS), two had multicentric Castleman's disease (MCD), and 15 did not exhibit HHV-8-related disease. Before the introduction of antiretroviral therapy (ART), plasma HHV-8-DNA was detected in 44% (7/16) of patients with KS and in 9% (1/11) of patients without HHV-8-related disease. Among patients with KS, elevated plasma HHV-8-DNA levels (≥0.05 copies/µL) correlated with the presence of CDC category C diseases other than KS (p = 0.0337), anti-HHV-8 antibody negativity (p = 0.0337), anemia (p = 0.0474), and thrombocytopenia (p = 0.0146). Following ART initiation, the percentage of patients positive for plasma HHV-8-DNA decreased from 44% (7/16) to 6% (1/17), and the percentage of patients positive for anti-HHV-8 antibodies increased from 44% (7/16) to 88% (15/17). Finally, plasma HHV-8-DNA positivity and anti-HHV-8 antibody negativity were observed in two patients with MCD. Our findings suggest that insufficient production of anti-HHV-8 antibodies was associated with HHV-8 viremia, and that anti-HHV-8 antibody production was recovered with ART; thus, indicating the possibility of involvement of humoral immunity in suppressing HHV-8 viremia.

Immune Reconstitution Inflammatory Syndrome Presenting as Disseminated Kaposi Sarcoma

We present a patient who was previously diagnosed with HIV and had multiple violaceous skin lesions at the time of his diagnosis. Following the initiation of antiretroviral therapy (ART), the number of lesions increased significantly and he developed shortness of breath, which prompted hospital admission for further workup. Biopsy of the skin lesions confirmed the diagnosis of Kaposi sarcoma (KS). Bronchoscopy with biopsy revealed KS lesions in his respiratory system. Imaging and biopsy confirmed KS invasion of lymph nodes. Due to widespread KS, he was diagnosed with immune reconstitution inflammatory syndrome (IRIS). Because of the lack of improvement on ART alone, he was started on chemotherapy, which decreased the size of existing skin lesions, stalled the development of new skin lesions, and led to symptom improvement. As a result of this case, we recommend that treatment teams have close follow-ups of patients started on ART and that they remain mindful of the possibility of IRIS. Disseminated KS may warrant a prompt response with chemotherapy to improve outcomes.

Plasma interleukin-7 correlation with human immunodeficiency virus RNA and CD4+ T cell counts, and interleukin-5 with circulating hepatitis B virus DNA may have implications in viral control

Chronic viral infections represent a leading cause of global morbidity and mortality. Chronic HBV, HCV, and HIV infections result in cytokine perturbations that may hold key implications in understanding the complex disease mechanisms driving virus persistence and/or resolution. Here, we determined the levels of various plasma cytokines using a commercial Bio-Plex Luminex cytokine array in chronic HBV (n = 30), HCV (n = 15), and HIV (n = 40) infections and correlated with corresponding plasma viral loads (PVLs) and liver parameters. We observed differential perturbations in cytokine profiles among the study groups. The cytokines levels positively correlated with PVL and liver transaminases. The monocyte-derived cytokines viz., MIP-1β, IL-8, and TNF-α, and Th2 cytokines like IL-4, IL-5, and IL-13 showed a better correlation with liver enzymes as compared to their corresponding PVLs. Our investigation also identified two cytokines viz., IL-5 and IL-7 that inversely correlated with HBV DNA and HIV PVLs, respectively. Regression analysis adjusted for age showed that every increase of IL-5 by one unit was associated with a reduction in HBV PVL by log10 0.4, whereas, every elevation by a unit of IL-7 was associated with decreased HIV PVL by log10 2.5. We also found that IL-7 levels correlated positively with absolute CD4+ T cell counts in HIV-infected patients. We concluded that plasma IL-5 and IL-7 may likely have a key role on viral control in HBV and HIV infections, respectively. A noteworthy increase in cytokines appears to bear protective and pathological significance, and indeed is reflective of the host's versatile immune armory against viral persistence.

Pulmonary Kaposi Sarcoma without Respiratory Symptoms and Skin Lesions in an HIV-Naïve Patient: A Case Report and Literature Review

Kaposi sarcoma (KS) is a multifocal lympho-angioproliferative, mesenchymal low-grade tumor associated with a γ2-herpesvirus, named Kaposi sarcoma-associated virus or human herpesvirus (KSHV/HHV8). The lung is considered a usual anatomical location of KS, despite being infrequent, often in association with extensive mucocutaneous lesions and very uncommonly as an isolated event. We report a case of a pulmonary KS (pKS) in a human immunodeficiency virus (HIV) naïve patient, which was atypical due to a lack of cutaneous involvement and an absence of respiratory symptoms. The pKS was initially identified as a tumoral suspected nodular lesion and only after immunohistochemical analysis was it characterized as KS. Furthermore, the diagnosis of pKS led to the discovery of the HIV-seropositive status of the patient, previously unknown. Our report underlines the importance of considering pKS even without skin lesions and as a first manifestation of HIV infection. We also reviewed literature on the current knowledge about pKS in people living with HIV (PLWH) to underline how one of the most common HIV/acquired immunodeficiency syndrome (AIDS) associated tumors can have a challenging localization and be difficult to recognize.

Viral and immunological markers of HIV-associated Kaposi sarcoma recurrence

Kaposi sarcoma (KS) is an AIDS-defining angio-proliferative malignancy highly prevalent in Sub-Saharan Africa. The main objective of this study was to determine the factors associated with recurrence of HIV-associated KS. We recruited a cohort of individuals on antiretroviral therapy who were in remission for HIV-associated KS after undergoing cytotoxic cancer chemotherapy. Collected variables included sociodemographic and clinical parameters, cytokines and chemokines, HIV viral loads, and CD4 counts. Compared to individuals who had KS recurrence, IL-5 was significantly higher at time of follow-up in individuals who had sustained remission (22.7pg/ml vs. 2.4pg/ml; p = 0.02); IL-6 was significantly higher at baseline and time of follow-up in individuals who had sustained remission, (18.4pg/ml vs. 0pg/ml; p = 0.01) and (18.0pg/ml vs. 0.18pg/ml; p = 0.03) respectively; IP-10 was significantly lower at baseline and at time of follow-up in individuals who had sustained remission, (534pg/ml vs. 920pg/ml; p = 0.04) and (446pg/ml vs.1098pg/ml; p = 0.01) respectively; while HIV viral load was significantly lower at baseline and at time of follow-up in individuals who had sustained remission, (0copies/ml vs. 113copies/ml; p = 0.004) and (0copies/ml vs. 152copies/ml; p = 0.025) respectively. Plasma levels of IL-5, IL-6, and IP-10 are associated with recurrence of HIV-associated KS, while persistently detectable HIV viral loads increase the risk of KS recurrence.

Cells of the Innate and Adaptive Immune Systems in Kaposi's Sarcoma

Kaposi's sarcoma (KS) is an angioproliferative malignancy whose associated etiologic agent is the Kaposi's sarcoma-associated herpesvirus (KSHV). KS is the most prevalent malignancy among HIV-infected individuals globally and is considered an AIDS-defining malignancy. The different forms of KS including HIV-associated KS, iatrogenic (immunosuppression-related) KS, and classical KS in elderly males suggest that immune cell dysregulation is among the key components in promoting KS development in KSHV-infected individuals. It is therefore expected that different cell types of the immune system likely play distinct roles in promoting or inhibiting KS development. This narrative review is focused on discussing cells of the innate and adaptive immune systems in KSHV infection and KS pathogenesis, including how these cells can be useful in the control of KSHV infection and treatment of KS.