Identification of equine herpesvirus 8 in donkey abortion: a case report

Background Equine herpesvirus-8 (EHV-8) is one of the most economically significant viruses that infect mammals of the genus Equus worldwide, which cause severe respiratory diseases and abortion in horses. However, there is no report of abortion caused by EHV-8 in donkeys. Case presentation The present case report is about a 4-year-old donkey having an abortion and showing a serious respiratory issue on the 296th day of pregnancy. Bacteriological and molecular tests were used to screen possible bacterial/viral pathogens to detect the etiological agent. Salmonella abortus equi, EHV-1, EHV-4, and EAV were all negative in the current study. EHV-8, on the other hand, was the only agent that was isolated and identified. Conclusions This was for the first time that EHV-8 had been isolated from a donkey in China. EHV-8 infection can cause abortion in donkeys; therefore, veterinarians and breeders should be aware of it.

Therapeutic management of a symptomatic Kaposi’s sarcoma patient with renal failure undergoing haemodialysis: A case report

Kaposi’s sarcoma (KS) is a rare inflammation-based vascular cancer involving the skin. The viral aetiology of KS is the human herpesvirus 8 (HHV-8). KS may be frequently diagnosed in immunosuppressed kidney-transplanted patients, while is less common in patients with dialysis. It is known that various immunological abnormalities can lead to impaired immune status in uremic patients. It is noteworthy that despite the incidence of KS in patients with renal impairment, only few cases have reported efficacy and safety profile of KS targeting anti-cancer drugs in this kidney disease population. Herein, we report the first case of a symptomatic KS patient with renal disease in haemodialysis and focus on its therapeutic management. We also review the main data available from literature regarding the safety of KS therapy in dialysis patients.

A case of Castleman disease with hemophagocytic syndrome derived from HHV8 infection

Background For a patient presenting with fever, multiple lymphadenopathy and splenomegaly, pathogen infection should be preferentially considered, followed by lymphoid malignancies. When traditional laboratory and pathological detection cannot find the pathogenic microorganism, metagenomic sequencing (MGS) which targets the person’s genome for exceptional genetic disorders may detect a rare pathogen. Case presentation Here, we introduced the diagnostic clue of a case of multicentric Castleman disease (MCD) with hemophagocytic syndrome which was elicited from the detection of human herpesvirus-8 in the blood of a HIV-1 infected person by MGS technology during pathogen inspection. This case highlights the need to increase the awareness of MCD among clinicians and pathologists. Conclusions MGS technology may play a pivotal role in providing diagnostic clues during pathogen inspection, especially when pathogens are not detectable by conventional methods.

Lymphoproliferative Neoplasms With Plasmablastic Morphology: An Overview and Diagnostic Approach

Context.— Plasmablastic morphology can be seen in several uncommon lymphoproliferative neoplasms. Sometimes it is difficult to distinguish these neoplasms from each other. Objective.— To review the current understanding of major lymphoproliferative neoplasms with plasmablastic morphology; summarize the clinical, morphologic, immunophenotypic, cytogenetic, and molecular characteristics of each disease entity; and highlight a practical approach for differential diagnosis. Data Sources.— Peer-reviewed medical literature and the authors' personal experience. Conclusions.— Plasmablastic lymphoma; plasmablastic myeloma; primary effusion lymphoma; human herpesvirus 8–positive diffuse large B-cell lymphoma, not otherwise specified; and anaplastic lymphoma kinase (ALK)–positive large B-cell lymphoma are major lymphoproliferative neoplasms with plasmablastic morphology. These neoplasms share many common morphologic and immunophenotypic characteristics. Definitive diagnosis requires a thorough understanding of disease phenotype and diagnostic criteria of each category. Recognition of expression pattern of Epstein-Barr virus–encoded small RNA, human herpesvirus 8, and ALK in these neoplasms is critical for diagnosis in cases with typical presentation. Additional ancillary studies and clinical findings may help in difficult cases.

Human herpesvirus 8 molecular mimicry of ephrin ligands facilitates cell entry and triggers EphA2 signaling

Human herpesvirus 8 (HHV-8) is an oncogenic virus that enters cells by fusion of the viral and endosomal cellular membranes in a process mediated by viral surface glycoproteins. One of the cellular receptors hijacked by HHV-8 to gain access to cells is the EphA2 tyrosine kinase receptor, and the mechanistic basis of EphA2-mediated viral entry remains unclear. Using X-ray structure analysis, targeted mutagenesis, and binding studies, we here show that the HHV-8 envelope glycoprotein complex H and L (gH/gL) binds with subnanomolar affinity to EphA2 via molecular mimicry of the receptor’s cellular ligands, ephrins (Eph family receptor interacting proteins), revealing a pivotal role for the conserved gH residue E52 and the amino-terminal peptide of gL. Using FSI-FRET and cell contraction assays, we further demonstrate that the gH/gL complex also functionally mimics ephrin ligand by inducing EphA2 receptor association via its dimerization interface, thus triggering receptor signaling for cytoskeleton remodeling. These results now provide novel insight into the entry mechanism of HHV-8, opening avenues for the search of therapeutic agents that could interfere with HHV-8–related diseases.

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.

Seroprevalence and molecular diversity of Human Herpesvirus 8 among people living with HIV in Brazzaville, Congo

Human herpesvirus 8 (HHV8) is endemic in Africa, although studies of this infection are rare in Congo. We evaluated seroprevalence and HHV-8 diversity among people living with HIV. We included 353 patients receiving highly active antiretroviral therapy. Antibodies against HHV-8 latency-associated nuclear antigen were detected by indirect immunofluorescence. In HHV-8 positive patients, we performed HHV-8 quantification in blood and saliva by real-time PCR and typing by Sanger sequencing of K1 open reading frame. HHV-8 seroprevalence was 19%, being male (odd ratio [OR] = 1.741, [95% Confidence interval {CI}, 0.97–3.07]; p = 0.0581) and having multiple sex partners before HIV diagnosis (OR = 1.682, [CI 95%, 0.97–2.92]; p = 0.0629) tended to be associated with HHV-8 seropositivity. Of the 64 HHV-8 seropositive patients, HHV-8 DNA was detected in 10 (16%) in saliva, 6 (9%) in whole-blood and in 2 (3%) in both whole-blood and saliva. Three out of 6 HHV-8 strains were subtypes A5, 2 subtype B1 and 1 subtype C. HHV-8 seroprevalence was relatively low with more frequent carriage in men, associated with asymptomatic oral excretion and a predominance of subtype A5. These data tend to support the hypothesis of horizontal transmission in people living with HIV in Brazzaville.