Inflammatory Cytokine Syndrome Research Articles

Sequencing of Kaposi's Sarcoma Herpesvirus (KSHV) genomes from persons of diverse ethnicities and provenances with KSHV-associated diseases demonstrate multiple infections, novel polymorphisms, and low intra-host variance.

Recently published near full-length KSHV genomes from a Cameroon Kaposi sarcoma case-control study showed strong evidence of viral recombination and mixed infections, but no sequence variations associated with disease. Using the same methodology, an additional 102 KSHV genomes from 76 individuals with KSHV-associated diseases have been sequenced. Diagnoses comprise all KSHV-associated diseases (KAD): Kaposi sarcoma (KS), primary effusion lymphoma (PEL), KSHV-associated large cell lymphoma (KSHV-LCL), a type of multicentric Castleman disease (KSHV-MCD), and KSHV inflammatory cytokine syndrome (KICS). Participants originated from 22 different countries, providing the opportunity to obtain new near full-length sequences of a wide diversity of KSHV genomes. These include near full-length sequence of genomes with KSHV K1 subtypes A, B, C, and F as well as subtype E, for which no full sequence was previously available. High levels of recombination were observed. Fourteen individuals (18%) showed evidence of infection with multiple KSHV variants (from two to four unique genomes). Twenty-six comparisons of sequences, obtained from various sampling sites including PBMC, tissue biopsies, oral fluids, and effusions in the same participants, identified near complete genome conservation between different biological compartments. Polymorphisms were identified in coding and non-coding regions, including indels in the K3 and K15 genes and sequence inversions here reported for the first time. One such polymorphism in KSHV ORF46, specific to the KSHV K1 subtype E2, encoded a mutation in the leucine loop extension of the uracil DNA glycosylase that results in alteration of biochemical functions of this protein. This confirms that KSHV sequence variations can have functional consequences warranting further investigation. This study represents the largest and most diverse analysis of KSHV genome sequences to date among individuals with KAD and provides important new information on global KSHV genomics.

Inflammasome activation in patients with Kaposi sarcoma herpesvirus–associated disorders

AbstractKaposi sarcoma herpesvirus (KSHV)–associated disorders include Kaposi sarcoma (KS), primary effusion lymphoma (PEL), KSHV–associated multicentric Castleman disease (MCD), and KS inflammatory cytokine syndrome (KICS). PEL, MCD, and KICS are associated with elevated circulating inflammatory cytokines. However, activation of the inflammasome, which generates interleukin-1 β (IL-1β) and IL-18 via active caspase-1/4/5, has not been evaluated in patients with KSHV-associated disorders (KADs). Herein we report that patients with HIV and ≥1 KAD present with higher plasma levels of IL-18 and increased caspase-1/4/5 activity in circulating monocytes compared with HIV-negative healthy volunteers (HVs) or people with HIV without KAD (PWH). Within KAD subtypes, KICS and MCD shared enhanced caspase-1/4/5 activity and IL-18 production compared with HVs and PWH, whereas patients with PEL showed remarkably high levels of inflammasome complex formation (known as apoptosis–associated speck-like protein containing a caspase recruitment domain). Moreover, caspase-1/4/5 activity and IL-18 plasma levels correlated with KSHV viral load, indicating KSHV–driven inflammasome activation in KAD. Accordingly, factors released by cells latently infected with KSHV triggered inflammasome activation and cytokine production in bystander monocytes in vitro. Finally, both supervised and unsupervised analyses with inflammasome measurements and other inflammatory biomarkers demonstrate a unique inflammatory profile in patients with PEL, MCD, and KICS as compared with KS. Our data indicate that detrimental inflammation in patients with KAD is at least partially driven by KSHV–induced inflammasome activation in monocytes, thus offering novel approaches to diagnose and treat these complex disorders.

KSHV vIL-6 enhances inflammatory responses by epigenetic reprogramming.

Kaposi sarcoma-associated herpesvirus (KSHV) inflammatory cytokine syndrome (KICS) is a newly described chronic inflammatory disease condition caused by KSHV infection and is characterized by high KSHV viral load and sustained elevations of serum KSHV-encoded IL-6 (vIL-6) and human IL-6 (hIL-6). KICS has significant immortality and greater risks of other complications, including malignancies. Although prolonged inflammatory vIL-6 exposure by persistent KSHV infection is expected to have key roles in subsequent disease development, the biological effects of prolonged vIL-6 exposure remain elusive. Using thiol(SH)-linked alkylation for the metabolic (SLAM) sequencing and Cleavage Under Target & Release Using Nuclease analysis (CUT&RUN), we studied the effect of prolonged vIL-6 exposure in chromatin landscape and resulting cytokine production. The studies showed that prolonged vIL-6 exposure increased Bromodomain containing 4 (BRD4) and histone H3 lysine 27 acetylation co-occupancies on chromatin, and the recruitment sites were frequently co-localized with poised RNA polymerase II with associated enzymes. Increased BRD4 recruitment on promoters was associated with increased and prolonged NF-κB p65 binding after the lipopolysaccharide stimulation. The p65 binding resulted in quicker and sustained transcription bursts from the promoters; this mechanism increased total amounts of hIL-6 and IL-10 in tissue culture. Pretreatment with the BRD4 inhibitors, OTX015 and MZ1, eliminated the enhanced inflammatory cytokine production. These findings suggest that persistent vIL-6 exposure may establish a chromatin landscape favorable for the reactivation of inflammatory responses in monocytes. This epigenetic memory may explain the greater risk of chronic inflammatory disease development in KSHV-infected individuals.

Insight into the Epigenetics of Kaposi's Sarcoma-Associated Herpesvirus.

Epigenetic reprogramming represents a series of essential events during many cellular processes including oncogenesis. The genome of Kaposi's sarcoma-associated herpesvirus (KSHV), an oncogenic herpesvirus, is predetermined for a well-orchestrated epigenetic reprogramming once it enters into the host cell. The initial epigenetic reprogramming of the KSHV genome allows restricted expression of encoded genes and helps to hide from host immune recognition. Infection with KSHV is associated with Kaposi's sarcoma, multicentric Castleman's disease, KSHV inflammatory cytokine syndrome, and primary effusion lymphoma. The major epigenetic modifications associated with KSHV can be labeled under three broad categories: DNA methylation, histone modifications, and the role of noncoding RNAs. These epigenetic modifications significantly contribute toward the latent-lytic switch of the KSHV lifecycle. This review gives a brief account of the major epigenetic modifications affiliated with the KSHV genome in infected cells and their impact on pathogenesis.

Deconstructing the liquid architecture of human herpesvirus 8 diseases.

Human herpesvirus 8 (HHV-8), also called Kaposi sarcoma herspesvirus (KSHV), causes several human tumours, which may be associated with systemic inflammation and body cavity effusions, including a form of multicentric Castleman disease (MCD) and a novel inflammatory syndrome, KSHV inflammatory cytokine syndrome (KICS). In this issue, Zhou et al. demonstrate that HHV-8-infected lambda-restricted plasmablasts can be detected in these effusions and can be used to distinguish MCD from other HHV-8 tumours as well as to categorise KICS into distinct clinicopathological groups. These findings open a path to an integrated clinicopathological approach to HHV-8-associated inflammatory diseases and may have clinical implications. Commentary on: Zhou et al. A novel approach for characterisation of KSHV-associated multicentric Castleman disease from effusions. Br J Haematol 2023;200:462-475.

A novel approach for characterization of KSHV-associated multicentric Castleman disease from effusions.

A biopsy of lymphoid tissue is currently required to diagnose Kaposi sarcoma-associated herpesvirus (KSHV)-associated multicentric Castleman disease (KSHV-MCD). Patients showing clinical manifestations of KSHV-MCD but no pathological changes of KSHV-MCD are diagnosed as KSHV inflammatory cytokine syndrome. However, a lymph node biopsy is not always feasible to make the distinction. A pathognomonic feature of lymph nodes in KSHV-MCD is the expansion of KSHV-infected, lambda-restricted but polyclonal plasmablasts. To investigate whether these cells also reside in extra-nodal sites, effusion from 11 patients with KSHV-MCD and 19 with KSHV inflammatory cytokine syndrome was analysed by multiparametric flow cytometry. A distinct, lambda-restricted plasmablastic population (LRP) with highly consistent immunophenotype was detected in effusions in 8/11 patients with KSHV-MCD. The same population was also observed in 7/19 patients with KSHV inflammatory cytokine syndrome. The detection of LRP stratified KSHV inflammatory cytokine syndrome into two clinically distinct subgroups; those with detectable LRP closely resembled KSHV-MCD, showing similar KSHV viral load, comparable severity of thrombocytopenia and hypoalbuminaemia, and similar incidences of hepatosplenomegaly. Collectively, the detection of LRP by flow cytometry can serve as a valuable tool in diagnosing KSHV-MCD. KSHV inflammatory cytokine syndrome with LRP in effusions may represent a liquid-form of KSHV-MCD.

Host-Level Susceptibility and IRF1 Expression Influence the Ability of IFN-γ to Inhibit KSHV Infection in B Lymphocytes.

Kaposi’s sarcoma-associated herpesvirus (KSHV) is associated with vascular endothelial cell tumor, Kaposi’s sarcoma (KS) and lymphoproliferative disorder, multicentric Castleman’s disease (MCD), primary effusion lymphoma (PEL) and KSHV inflammatory cytokine syndrome (KICS). Dysregulation of proinflammatory cytokines is found in most KSHV associated diseases. However, little is known about the role of host microenvironment in the regulation of KSHV establishment in B cells. In the present study, we demonstrated that IFN-γ has a strong inhibitory effect on KSHV infection but only in a subset of tonsil-derived lymphocyte samples that are intrinsically more susceptible to infection, contain higher proportions of naïve B cells, and display increased levels of IRF1 and STAT1-pY701. The effect of IFN-γ in responsive samples was associated with increased frequencies of germinal center B cells (GCB) and decreased infection of plasma cells, suggesting that IFN-γ-mediated modulation of viral dynamics in GC can inhibit the establishment of KSHV infection.

Characteristics of patients admitted to the ICU with Kaposi sarcoma herpesvirus-associated diseases.

There are four conditions caused by Kaposi sarcoma herpesvirus (KSHV): Kaposi sarcoma, KSHV-associated multicentric Castleman disease (MCD), primary effusion lymphoma (PEL), and KSHV inflammatory cytokine syndrome (KICS). These KSHV-associated disorders (KADs) often occur in people with HIV and can lead to multiorgan dysfunction requiring admission to the ICU. However, little is known about patient outcomes in this setting. A retrospective study of patients with KADs admitted to the ICU between 2010 and 2021 was conducted, examining KAD admission diagnoses, HIV characteristics, selected cytokine profiles, and ICU interventions. Primary outcomes were 60-day and median overall survival from ICU admission to death from any cause. Forty-seven patients (all but one with HIV coinfection) were included. At ICU admission, 44 patients (94%) were on antiretroviral therapy with a median CD4 + count of 88 cells/μl and HIV viral load of 23 copies/ml. The most common presentation was respiratory failure alone (19%) or with hypotension (17%). Twenty-two (47%) patients had presumed KICS (with or without Kaposi sarcoma) at admission and an additional KAD was diagnosed in 36% of these patients. IL-6 levels did not vary across KAD subtype. Twenty (43%) patients received KAD-directed therapy in the ICU. Sixty-day survival was 70% and median overall survival was 9 months. The majority of patients with HIV and KADs admitted to the ICU had well controlled HIV. Additional KAD were diagnosed during ICU admission in a proportion of patients who presented with presumed KICS. Critical illness did not preclude a subset of patients from receiving KAD-directed therapy in the ICU.

Maladies immunologiques et hématologiques liées à HHV-8

HHV-8 is an oncogenic Gammaherpesvirinae discovered in 1994 during the HIV pandemic. It is the causative agent of Kaposi's sarcoma, and is also associated with the occurrence of several aggressive B lymphoproliferative disorders. Most of them occur in an immunosuppression setting, usually due to HIV infection. Multicentric HHV8-associated Castleman's disease and KSHV Inflammatory Cytokine Syndrome (KICS) are primarily reactive entities with prominent systemic features. They illustrate the cytokinic storm induced by HHV-8 in its cell host. On the other hand, HHV-8 can drive proliferation and lymphomagenesis of its plasmablastic cell host, and is associated with a risk to develop aggressive lymphomas with plasmacytic differenciation. Primary effusion lymphoma usually localizes in body cavities and may affect other extra-nodal sites ; its prognostic is poor. Diffuse large B-cell lymphoma HHV-8, NOS affect more commonly nodes and blood and evolve from infected cell of HHV-8 associated Castleman disease. On the contrary, germinotropic lymphoproliferative disorders presents mainly as localized adenopathy with indolent course, and show polyclonality. Histology plays a key role in distinguishing these different entities and need expert reviewing, especially since they may be associated with each other. Besides lymphoproliferative disorders, HHV8 is associated with various hematological manifestations. The aim of this review is to provide an update on the presentation, diagnosis, and management of immunologic and hematologic complications associated with HHV-8.

Castleman disease.

Castleman disease (CD), a heterogeneous group of disorders that share morphological features, is divided into unicentric CD and multicentric CD (MCD) according to the clinical presentation and disease course. Unicentric CD involves a solitary enlarged lymph node and mild symptoms and excision surgery is often curative. MCD includes a form associated with Kaposi sarcoma herpesvirus (KSHV) (also known as human herpesvirus 8) and a KSHV-negative idiopathic form (iMCD). iMCD can present in association with severe syndromes such as TAFRO (thrombocytopenia, ascites, fever, reticulin fibrosis and organomegaly) or POEMS (polyneuropathy, organomegaly, endocrinopathy, monoclonal plasma cell disorder and skin changes). KSHV-MCD often occurs in the setting of HIV infection or another cause of immune deficiency. The interplay between KSHV and HIV elevates the risk for the development of KSHV-induced disorders, including KSHV-MCD, KSHV-lymphoproliferation, KSHV inflammatory cytokine syndrome, primary effusion lymphoma and Kaposi sarcoma. A CD diagnosis requires a multidimensional approach, including clinical presentation and imaging, pathological features, and molecular virology. B cell-directed monoclonal antibody therapy is the standard of care in KSHV-MCD, and anti-IL-6 therapy is the recommended first-line therapy and only treatment of iMCD approved by the US FDA and EMA.

Recent Advances in Developing Treatments of Kaposi's Sarcoma Herpesvirus-Related Diseases.

Kaposi-sarcoma-associated herpesvirus (KSHV) or human herpesvirus 8 (HHV-8) is the causative agent of several malignancies, including Kaposi’s sarcoma (KS), primary effusion lymphoma (PEL), and multicentric Castleman’s disease (MCD). Active KSHV replication has also been associated with a pathological condition called KSHV inflammatory cytokine syndrome (KICS), and KSHV may play a role in rare cases of post-transplant polyclonal lymphoproliferative disorders. Several commonly used herpesviral DNA polymerase inhibitors are active against KSHV in tissue culture. Unfortunately, they are not always efficacious against KSHV-induced diseases. To improve the outcome for the patients, new therapeutics need to be developed, including treatment strategies that target either viral proteins or cellular pathways involved in tumor growth and/or supporting the viral life cycle. In this review, we summarize the most commonly established treatments against KSHV-related diseases and review recent developments and promising new compounds that are currently under investigation or on the way to clinical use.

Recruitment of phospholipase Cγ1 to the non-structural membrane protein pK15 of Kaposi Sarcoma-associated herpesvirus promotes its Src-dependent phosphorylation.

Kaposi Sarcoma-associated herpesvirus (KSHV) causes three human malignancies, Kaposi Sarcoma (KS), Primary Effusion Lymphoma (PEL) and the plasma cell variant of multicentric Castleman’s Disease (MCD), as well as an inflammatory cytokine syndrome (KICS). Its non-structural membrane protein, pK15, is among a limited set of viral proteins expressed in KSHV-infected KS tumor cells. Following its phosphorylation by Src family tyrosine kinases, pK15 recruits phospholipase C gamma 1 (PLCγ1) to activate downstream signaling cascades such as the MEK/ERK, NFkB and PI3K pathway, and thereby contributes to the increased proliferation and migration as well as the spindle cell morphology of KSHV-infected endothelial cells. Here, we show that a phosphorylated Y481EEVL motif in pK15 preferentially binds into the PLCγ1 C-terminal SH2 domain (cSH2), which is involved in conformational changes occurring during the activation of PLCγ1 by receptor tyrosine kinases. We determined the crystal structure of a pK15 12mer peptide containing the phosphorylated pK15 Y481EEVL motif in complex with a shortened PLCγ1 tandem SH2 (tSH2) domain. This structure demonstrates that the pK15 peptide binds to the PLCγ1 cSH2 domain in a position that is normally occupied by the linker region connecting the PLCγ1 cSH2 and SH3 domains. We also show that longer pK15 peptides containing the phosphorylated pK15 Y481EEVL motif can increase the Src-mediated phosphorylation of the PLCγ1 tSH2 region in vitro. This pK15-induced increase in Src-mediated phosphorylation of PLCγ1 can be inhibited with the small pK15-derived peptide which occupies the PLCγ1 cSH2 domain. Our findings thus suggest that pK15 may act as a scaffold protein to promote PLCγ1 activation in a manner similar to the cellular scaffold protein SLP-76, which has been shown to promote PLCγ1 activation in the context of T-cell receptor signaling. Reminiscent of its positional homologue in Epstein-Barr Virus, LMP2A, pK15 may therefore mimic aspects of antigen-receptor signaling. Our findings also suggest that it may be possible to inhibit the recruitment and activation of PLCγ1 pharmacologically.

Identification of allosteric regulation sites of Kaposis sarcoma virus DNA polymerase to discover its specific inhibitors via analysis of correlated intramolecular motions

Human herpesvirus 8 (HHV8) also known as Kaposi sarcoma herpesvirus (KSHV) is a DNA virus associated with several dangerous diseases (Castleman disease, inflammatory cytokine syndrome, Kaposi sarcoma itself, etc). The exceptional importance of DNA-dependent DNA polymerases (DNA pols) in double-strand DNA viruses' lifecycle makes them attractive targets for specific low-weight molecular inhibitors, which can be used as antiviral drugs. Among the drug discovery strategies, the search/design of allosteric inhibitors of target enzymes seems to be the most promising. As a rule, allosteric regulatory sites have individual amino acid compositions, and the selectivity of the appropriate allosteric inhibitors is much higher compared to competitive inhibitors, especially in the case of nucleotide-binding enzymes. The general structural regularities of the location of allosteric regulation sites on the protein surface remain unclear. However, it is quite natural to assume some interdependence between behavior of amino acids in active and allosteric binding site that can be revealed by correlation analysis of intramolecular motions. Thus, the aim of this work was identification of site(-s) of allosteric regulation of KSHV DNA pol for the next rational design / search for compounds - potential drugs against KSHV dependent diseases. According to the aim the following tasks are set: to calculate the molecular dynamics of KSHV DNA polymerase as well as HIV reverse transcriptase for which allosteric regulation sites are known; to evaluate a correlation between motions in active and allosteric site of HIV reverse transcriptase and on the basis of these data to determine a localization of such site(-s) on the surface of KSHV DNA polymerase; to carry out a molecular docking of several compounds with known antipolymerase activity into the identified site of allosteric regulation and estimate the appropriate binding energies. As a primary result, the correlation between the motions of amino acid residues in the active and allosteric site of HIV reverse transcriptase was revealed. The corresponding correlation coefficients are in the range of 0.55–0.62. Thus, the initial hypothesis about interdependence of the behavior of the active site and the site of allosteric regulation was confirmed. In the KSHV DNA pol was revealed a region in the range from 420 to 460 amino acid residue which motions correlate with the motions of the active site of this enzyme. The correlation coefficients are in the range of 0.52–0.57. Analysis of the molecular surface of the KSHV DNA pol revealed a site able to bind small organic compounds, which seems to be allosteric regulation site of KSHV DNA pol. As a result of molecular docking, two compounds with binding energies of -22.41 and -20.65 kJ/mol respectively were identified as potential non-competitive inhibitors of KSVH DNA pol. The identified compounds can be structural prototypes for the development of new drugs against KSHV caused pathologies. The proposed approach to the identification of allosteric regulatory sites by analysis of intramolecular correlated motions can be used for rational design/search of high selective inhibitors with a non-competitive mechanism of action for a wide range of enzymes.

Novel Functions and Virus-Host Interactions Implicated in Pathogenesis and Replication of Human Herpesvirus 8.

Human herpesvirus 8 (HHV-8) is classified as a γ2-herpesvirus and is related to Epstein-Barr virus (EBV), a γ1-herpesvirus. One important aspect of the γ-herpesviruses is their association with neoplasia, either naturally or in animal model systems. HHV-8 is associated with B-cell-derived primary effusion lymphoma (PEL) and multicentric Castleman's disease (MCD), endothelial-derived Kaposi's sarcoma (KS), and KSHV inflammatory cytokine syndrome (KICS). EBV is also associated with a number of B-cell malignancies, such as Burkitt's lymphoma, Hodgkin's lymphoma, and posttransplant lymphoproliferative disease, in addition to epithelial nasopharyngeal and gastric carcinomas. Despite the similarities between these viruses and their associated malignancies, the particular protein functions and activities involved in key aspects of virus biology and neoplastic transformation appear to be quite distinct. Indeed, HHV-8 specifies a number of proteins for which counterparts had not previously been identified in EBV, other herpesviruses, or even viruses in general, and these proteins are believed to play vital functions in virus biology and to be involved centrally in viral pathogenesis. Additionally, a set of microRNAs encoded by HHV-8 appears to modulate the expression of multiple host proteins to provide conditions conductive to virus persistence within the host and possibly contributing to HHV-8-induced neoplasia. Here, we review the molecular biology underlying these novel virus-host interactions and their potential roles in both virus biology and virus-associated disease.

Evidence for altered host genetic factors in KSHV infection and KSHV-related disease development.

SummaryKaposi's sarcoma‐associated herpesvirus (KSHV) is the etiological agent of Kaposi's sarcoma (KS), the most common AIDS‐related malignancy. It also causes other rare, but certainly underreported, KSHV‐associated pathologies, namely primary effusion lymphoma, multicentric Castleman disease and KSHV inflammatory cytokine syndrome. Epidemiology and pathogenicity studies point to the potential for host genetic predisposition to KSHV infection and/or the subsequent development of KSHV‐associated pathologies partly explaining the peculiar geographic and population‐specific incidence of KSHV and associated pathologies and discrepancies in KSHV exposure and infection and KSHV infection and disease development. This review consolidates the current knowledge of host genetic factors involved in the KSHV‐driven pathogenesis. Studies reviewed here indicate a plausible connection between KSHV susceptibility and host genetic factors that affect either viral access to host cells via entry mechanisms or host innate immunity to viral infection. Subsequent to infection, KSHV‐associated pathogenesis, reviewed here primarily in the context of KS, is likely influenced by an orchestrated concert of innate immune system interactions, downstream inflammatory pathways and oncogenic mechanisms. The association studies reviewed here point to interesting candidate genes that may prove important in achieving a more nuanced understanding of the pathogenesis and therapeutic targeting of KSHV and associated diseases. Recent studies on host genetic factors suggest numerous candidate genes strongly associated with KSHV infection or subsequent disease development, particularly innate immune system mediators. Taken together, these contribute toward our understanding of the geographic prevalence and population susceptibility to KSHV and KSHV‐associated diseases.

RARE CASE OF OVERLAPPING PRIMARY EFFUSION LYMPHOMA AND KAPOSI SARCOMA INFLAMMATORY CYTOKINE SYNDROME IN IMMUNOSUPRESSED PATIENT

SESSION TITLE: Medical Student/Resident Critical Care Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: October 18-21, 2020 INTRODUCTION: Kaposi’s sarcoma-associated herpes virus (KSHV) is a potent oncogenic and immunomodulatory virus. We present a patient with high KSHV viral load with primary effusion lymphoma (PEL) and the rarely reported Kaposi’s sarcoma inflammatory cytokine syndrome (KSICS). CASE PRESENTATION: 31-year-old male with AIDS (CD4 of 45 cell/µL, viral load 170,000) and Kaposi Sarcoma treated with liposomal doxorubicin, admitted for shortness of breath (SOB), lower extremity (LE) and scrotal edema. Physical examination: tachycardia, bibasilar crackles, 3+ pitting edema of LE extending to the sacrum, and violaceous, erythematous KS lesions on the torso. Initial studies notable for anemia (Hgb 9.0 g/dl), otherwise unremarkable including brain natriuretic peptide and microbiology studies. A chest x-ray demonstrated bilateral pleural effusions with loculation on the left, which was later confirmed on a chest computed tomography scan, that also revealed enlarged mediastinal lymph nodes. Echocardiography showed preserved ejection fraction. A doppler ultrasound of LE was negative for deep vein thrombosis. During hospital course, patient became progressively anemic, hemodynamically unstable and profoundly SOB, ultimately requiring transfer to the intensive care unit where he was intubated and started on vasopressors. A thoracentesis with cytology positive for large pleomorphic lymphocytes, CD45+/HHV8+/EBER+ by immunohistochemistry. Flow cytometry showed monotypic B-cell population positive for HLA-DR, CD38, CD45 (dim), and kappa light chain (dim) restricted, consistent with a diagnosis of PEL. Serum studies demonstrated markedly elevated levels of IL6 and IL10 and the clinical presentation suggested a rare condition associated with KSHV, KSICS. The patient unfortunately died despite resuscitative efforts. DISCUSSION: PEL is the least common of all HIV related lymphomas and presents as lymphomatous growth in a liquid phase in a body cavity without extracavitary lesions. The pathogenic mechanism of KSHV is uncertain but almost all cases are associated with this virus. Malignant cells are monoclonal B cells that express CD38 and contain KSHV viral inclusions and the majority demonstrate EBV coinfection . Another disease diagnosed in patient is KSICS, a rarely reported systemic inflammatory syndrome associated with high KSHV viral load and elevated IL6 and IL10, secreted by infected cells. Presentation is similar to sepsis but without obvious source of infection. CONCLUSIONS: This case illustrates varying and overlapping presentations of KSHV infection in immunocompromised patient. Therapy does not exist and KS could not be treated due to the poor condition of patients. Patients have a high mortality rate and often misdiagnosed. Our patient received antibiotics for the presumptive sepsis before a diagnosis was made. It will be important to recognize this syndrome early to support attempts to develop effective therapies. Reference #1: Narkhede M, Arora S, Ujjani C. Primary effusion lymphoma: current perspectives. Onco Targets Ther. 2018;11:3747–3754. Published 2018 Jun 28. doi:10.2147/OTT.S167392 Reference #2: Polizzotto MN, Uldrick TS, Hu D, Yarchoan R. Clinical Manifestations of Kaposi Sarcoma Herpesvirus Lytic Activation: Multicentric Castleman Disease (KSHV-MCD) and the KSHV Inflammatory Cytokine Syndrome [published correction appears in Front Microbiol. 2017 Aug 21;8:1572]. Front Microbiol. 2012;3:73. Published 2012 Mar 2. doi:10.3389/fmicb.2012.00073 DISCLOSURES: No relevant relationships by Arsenije Kojadinovic, source=Web Response No relevant relationships by Prabhjot Mundi, source=Web Response No relevant relationships by Pahnwat Taweesedt, source=Web Response

Evaluation of IL-2, IL-4, IL-6, IL-10, TNF-α, and IFN-γ cytokines in HIV/HHV-8 coinfection.

Imbalance in the immune response is one of the main pathogenic mechanisms of diseases related with human immunodeficiency virus (HIV)/human gammaherpesvirus 8 (HHV-8) coinfection, such as Kaposi's sarcoma (KS), primary effusion lymphoma (PEL), multicentric Castleman disease (MCD) and the Kaposi's sarcoma-associated herpesvirus inflammatory cytokine syndrome (KICS). However, significant changes in pro- and anti-inflammatory cytokine levels may be observed in HIV/HHV-8 individuals who are negative for KS, PEL, MCD, and/or KICS. In this study, serum levels of interleukin-2 (IL-2), IL-4, IL-6, IL-10, tumor nucrosis factor α (TNF-α) and interferon γ (IFN-γ) were assessed in 69 HIV and 48 HIV/HHV-8 individuals, all negatives for HHV-8-related diseases. The cytokines were measured by flow cytometry and analyzed by the Mann-Whitney test. The p < .05 and 95% confidence interval were considered in all analyzes. IL-4 (p = .0155), IL-6 (p = .0036), and IL-10 (p = .0036) levels were significantly higher in HIV/HHV-8 patients than in the HIV group. On the other hand, IL-2 (p = .2295), TNF-α (p = .1216) and IFN-γ (p = .1178) did not differ between the groups analyzed. To our knowledge, to date, this is the first report on significant differences in the levels of IL-4 and IL-6 in HIV versus HIV/HHV-8 individuals. Finally, these early findings are important as a prognostic tool and contribute to clarifying the HHV-8-host interaction.

Cytokine-Targeted Therapeutics for KSHV-Associated Disease.

Kaposi’s sarcoma-associated herpesvirus (KSHV) also known as human herpesvirus 8 (HHV-8), is linked to several human malignancies including Kaposi sarcoma (KS), primary effusion lymphoma (PEL), multicentric Castleman’s disease (MCD) and recently KSHV inflammatory cytokine syndrome (KICS). As with other diseases that have a significant inflammatory component, current therapy for KSHV-associated disease is associated with significant off-target effects. However, recent advances in our understanding of the pathogenesis of KSHV have produced new insight into the use of cytokines as potential therapeutic targets. Better understanding of the role of cytokines during KSHV infection and tumorigenesis may lead to new preventive or therapeutic strategies to limit KSHV spread and improve clinical outcomes. The cytokines that appear to be promising candidates as KSHV antiviral therapies include interleukins 6, 10, and 12 as well as interferons and tumor necrosis factor-family cytokines. This review explores our current understanding of the roles that cytokines play in promoting KSHV infection and tumorigenesis, and summarizes the current use of cytokines as therapeutic targets in KSHV-associated diseases.

Elevated IL-13 in effusions of patients with HIV and primary effusion lymphoma as compared with other Kaposi sarcoma herpesvirus-associated disorders.

To assess the cytokine and viral profiles of effusions and peripheral blood among patients diagnosed with HIV and Kaposi sarcoma herpesvirus [KSHV, also known as human herpesvirus 8 (HHV-8)]-associated conditions. Retrospective comparative study evaluating clinicopathologic findings in patients with HIV and KSHV-associated conditions presenting with an effusion between 2010 and 2018. Paired peripheral blood and effusion samples collected at the time of pathological diagnosis of KSHV-associated conditions [Kaposi sarcoma, KSHV-associated multicentric Castleman disease (KSHV-MCD), primary effusion lymphoma (PEL), or KSHV-associated inflammatory cytokine syndrome (KICS)] were evaluated for disease-specific and compartment-specific (effusion vs. blood) characteristics. We assessed 12 cytokines, KSHV viral DNA (KSHV-VL), and Epstein--Barr virus (EBV) viral DNA (EBV-VL). Nine patients had PEL, five patients had KSHV-MCD, and eight patients met criteria for KICS; all but one patient had concurrent Kaposi sarcoma in addition to these conditions. PEL effusions had substantially higher levels of IL-13 (median 16.9 pg/ml; interquartile range 9.7--26.9 pg/ml) compared with KSHV-MCD (median <0.114 pg/ml; P = 0.0037) or KICS (median <0.114 pg/ml; P = 0.0003) effusions. IL-13 was also higher in PEL effusions as compared with serum (median <0.12 ng/ml; P = 0.007). KSHV-VL levels were significantly higher in PEL effusions as compared with KICS effusions (median 31 × 10 vs. 569 copies/million-cell equivalent; P = 0.0005) or KSHV-MCD effusions (median 231,884 copies/million-cell equivalent; P = 0.02). PEL effusions had a distinct profile as compared to other KSHV-associated diseases with regard to elevated IL-13 and KSHV-VL. These findings may provide insights into PEL pathogenesis and aid in diagnosis.

Dual infection and recombination of Kaposi sarcoma herpesvirus revealed by whole-genome sequence analysis of effusion samples.

Kaposi sarcoma herpesvirus (KSHV) is the etiological agent of three malignancies, Kaposi sarcoma (KS), primary effusion lymphoma (PEL) and KSHV-associated multicentric Castelman disease. KSHV infected patients may also have an interleukin six-related KSHV-associated inflammatory cytokine syndrome. KSHV-associated diseases occur in only a minority of chronically KSHV-infected individuals and often in the setting of immunosuppression. Mechanisms by which KSHV genomic variations and systemic co-infections may affect the pathogenic pathways potentially leading to these diseases have not been well characterized in vivo. To date, the majority of comparative genetic analyses of KSHV have been focused on a few regions scattered across the viral genome. We used next-generation sequencing techniques to investigate the taxonomic groupings of viruses from malignant effusion samples from fourteen participants with advanced KSHV-related malignancies, including twelve with PEL and two with KS and elevated KSHV viral load in effusions. The genomic diversity and evolutionary characteristics of nine isolated, near full-length KSHV genomes revealed extensive evidence of mosaic patterns across all these genomes. Further, our comprehensive NGS analysis allowed the identification of two distinct KSHV genome sequences in one individual, consistent with a dual infection. Overall, our results provide significant evidence for the contribution of KSHV phylogenomics to the origin of KSHV subtypes. This report points to a wider scope of studies to establish genome-wide patterns of sequence diversity and define the possible pathogenic role of sequence variations in KSHV-infected individuals.