Retrospective testing for mpox virus in routine STI screens from men who have sex with men in England, August-October 2022.

OBJECTIVES: A global outbreak of mpox (monkeypox) has been ongoing since 2022, with most cases in the UK detected in gay, bisexual and other men who have sex with men (GBMSM). Asymptomatic and pauci-symptomatic mpox infection has been reported outside of the UK. We aimed to investigate whether mpox could be detected in specimens from GBMSM in England who were attending sexual health services (SHSs) for asymptomatic sexually transmitted infection screening. METHODS: Anonymised, residual clinical specimens from GBMSM undertaking routine asymptomatic screening for gonorrhoea (Neisseria gonorrhoeae (NG)) and chlamydia (Chlamydia trachomatis (CT)) infection were tested for the presence of mpox virus. Specimens were collected between 1 August and 7 October 2022 from three SHSs in high-mpox incidence areas in England. Testing was performed using a dual-clade, mpox virus-specific real-time PCR. RESULTS: During the collection period, 2927 clinical specimens (951 pharyngeal swabs, 1022 urine specimens and 954 rectal swabs) were obtained from 1159 GBMSM. Mpox virus was detected in four specimens from two participants who attended the same SHS at different times (the first during the week 8-12 of August, the second during the week 19-23 of September). One participant was positive in the urine specimen only, while the other tested positive at all three sites. CONCLUSIONS: A very low prevalence (2 of 1159, 0.17%) of mpox infection was detected in GBMSM attending SHS in England for asymptomatic NG/CT screening, suggesting that undetected infection in this population was unlikely to be a main driver of transmission. Confirmed mpox cases in the UK declined from over 1100 per month in June and July to 764 cumulatively during the collection period. These data give reassurance that the observed reduction in cases during the collection period was not due to undetected infection or changes in presentation among SHS attendees. Currently, there is insufficient evidence to support routine testing of asymptomatic GBMSM for mpox infection in England.

Use of natural cysteine protease inhibitors in limiting SARS-Co-2 fusion into human respiratory cells.

Specific antibodies that humans acquire as a result of disease or after vaccination are needed to effectively suppress infection with a specific variant of SARS CoV-2 virus. The S protein of the D614G variant of coronavirus is used as an antigen in known vaccines to date. It is known that COVID-19 disease resulting from infection with this coronavirus can often be very dangerous to the health and lives of patients. In contrast, vaccines produce antibodies against an older version of the protein S-D614G (January 2020) and therefore have difficulty recognizing new variants of the virus. In our project we propose to obtain specific and precise antibodies by means of so-called controlled infection against specific infectious variants of the SARS-CoV-2 virus "here and now". Currently, several variants of this pathogen have already emerged that threaten the health and lives of patients. We propose to reduce this threat by partially, but not completely, blocking the fusion mechanism of the SARS-CoV-2 virus into human respiratory cells. According to our plan, this can be achieved by inhibiting cathepsin L activity in respiratory cells, after introducing natural and non-toxic cysteine protease inhibitors into this area. We obtain these inhibitors by our own method from natural, "human body friendly" natural resources. We hypothesize that blocking cathepsin L will reduce the number of infecting viruses in cells to such an extent that COVID-19 developing in infected individuals will not threaten their health and life. At the same time, the number of viruses will be sufficient for the body's own immune system to produce precise antibodies against a specific version of this pathogen.

Sex Differences in Innate Immune Response of Peripheral Blood Leukocytes of Alzheimer's Disease Patients.

Neurodegenerative disorders, including Alzheimer's disease (AD), are associated with a disruption of normal immune function that could potentially impact the brain. In AD sex and gender have been noted as relevant to disease prevalence or clinical manifestation. It is suggested that disease progression could vary as a result of the different inflammation state among males and females. The objective was to investigate sex-dependent difference in innate immunity of AD patients and healthy, age-matched controls. The level of innate immunity was measured with test based on peripheral blood leukocytes (PBLs) resistance to viral infection (vesicular stomatitis virus, VSV) ex vivo. Cytokine: TNF-α, IFN-γ, IL-1ß, IL-10 production by uninfected and VSV-infected PBLs ex vivo with enzyme-linked immunosorbent assay were examined. In contrast to controls, women with AD exhibit lower average level of innate immunity than AD men. The mean level of TNF-α, IL-10 and IL-1ß was higher in AD men than in AD women whereas such changes were not observed among controls. The level of IFN-γ was higher in AD than in controls. PBLs from AD did not increase IFN-γ production after viral infection in contrast to controls. Leukocytes from women with AD exhibited a weaker response to viral infection and much less cytokine production compared to men with AD. It is important to consider sex as a biological variable in AD as it shows promises to advance our understanding of mechanisms of AD pathology and may be the basis for future treatment of AD.

Inhibition of Human Respiratory Influenza A Virus and Human Betacoronavirus-1 by the Blend of Double-Standardized Extracts of Aronia melanocarpa (Michx.) Elliot and Sambucus nigra L.

Viral and bacterial diseases are among the greatest concerns of humankind since ancient times. Despite tremendous pharmacological progress, there is still a need to search for new drugs that could treat or support the healing processes. A rich source of bioactive compounds with antiviral potency include plants such as black chokeberry and elderberry. The aim of this study was to assess the in vitro antiviral ability of an originally designed double-standardized blend of extracts from Aronia melanocarpa (Michx.) Elliot and Sambucus nigra L. (EAM-ESN) or separated extracts of A. melanocarpa (EAM) or S. nigra (ESN) against four human respiratory tract viruses: influenza A virus (A/H1N1), betacoronavirus-1 (HCoV-OC43) belonging to the same ß-coronaviruses as the current pandemic SARS-CoV-2, human herpesvirus type 1 (HHV-1), and human adenovirus type 5 (HAdV-5). Antiviral assays (AVAs) were used to evaluate the antiviral activity of the plant extracts in a cell-present environment with extracts tested before, simultaneously, or after viral infection. The virus replication was assessed using the CPE scale or luminescent assay. The EAM-ESN blend strongly inhibited A/H1N1 replication as well as HCoV-OC43, while having a limited effect against HHV-1 and HAdV-5. This activity likely depends mostly on the presence of the extract of S. nigra. However, the EAM-ESN blend possesses more effective inhibitory activity toward virus replication than its constituent extracts. A post-infection mechanism of action of the EAM-ESN make this blend the most relevant for potential drugs and supportive treatments; thus, the EAM-ESN blend might be considered as a natural remedy in mild, seasonal respiratory viral infections.

The Impact of Exosomes/Microvesicles Derived from Myeloid Dendritic Cells Cultured in the Presence of Calcitriol and Tacalcitol on Acute B-Cell Precursor Cell Lines with MLL Fusion Gene.

Vitamin D analogs (VDAs) may directly inhibit the growth of normal and malignant (derived from acute lymphoblastic leukemia (ALL)) B cells, as both types of cells express vitamin D receptor (VDR). We performed anti-proliferative, morphology tests and phenotyping to evaluate the sensitivity of monocytes and iDCs (immature myeloid-derived dendritic cells) on calcitriol and tacalcitol treatment, phenotyping, morphology, and size distribution measurement to determine the characteristics of microvesicles (MVs) and exosomes (EXs) derived from them and, finally, phenotyping and Elisa test to determine the effects of VDAs on modulation of the phenotype of B cells through extracellular vesicles (EVs) released by iDCs. Our results confirmed that both SC cells and iDCs were sensitive to the VDAs and showed altered surface expression of markers associated with monocyte differentiation, which was resulting in the phenotypic changes in EVs derived from them. We also showed that obtained EVs could change the morphology and phenotype of ALL-B-derived precursor cells in a different way, depending on their origin. The differential effect of VDAs on ALL-B cells, which was associated with increased or decreased expression of CD27, CD24, CD38, and CD23 expression, was observed. Hence, further studies to explain the modulation in the composition of EVs by VDAs are required.

Inverse Correlation Between Alzheimer's Disease and Cancer: Short Overview.

The negative association between Alzheimer's disease (AD) and cancer suggests that susceptibility to one disease may protect against the other. When biological mechanisms of AD and cancer and relationship between them are understood, the unsolved problem of both diseases which still touches the growing human population could be overcome. Actual information about biological mechanisms and common risk factors such as chronic inflammation, age-related metabolic deregulation, and family history is presented here. Common signaling pathways, e.g., p53, Wnt, role of Pin1, and microRNA, are discussed as well. Much attention is also paid to the potential impact of chronic viral, bacterial, and fungal infections that are responsible for the inflammatory pathway in AD and also play a key role to cancer development. New data about common mechanisms in etiopathology of cancer and neurological diseases suggests new therapeutic strategies. Among them, the use of nilotinib, tyrosine kinase inhibitor, protein kinase C, and bexarotene is the most promising.

Novel betulin dicarboxylic acid ester derivatives as potent antiviral agents: Design, synthesis, biological evaluation, structure-activity relationship and in-silico study.

The search for new methods of antiviral therapy is primarily focused on the use of substances of natural origin. In this context, a triterpene compound, betulin 1, proved to be a good starting point for derivatization. Thirty-eight betulin acid ester derivatives were synthetized, characterized, and tested against DNA and RNA viruses. Several compounds exhibited 4- to 11-fold better activity against Enterovirus E (compound 5 EC50: 10.3 µM) and 3- to 6-fold better activity against Human alphaherpesvirus 1 (HHV-1; compound 3c EC50: 17.2 µM). Time-of-addition experiments showed that most of the active compounds acted in the later steps of the virus replication cycle (e.g., nucleic acid/protein synthesis). Further in-silico analysis confirmed in-vitro data and demonstrated that interactions between HHV-1 DNA polymerase and the most active compound, 3c, were more stable than interactions with the parent non-active betulin 1.

Characterisation of Phage Susceptibility Variation in Salmonellaenterica Serovar Typhimurium DT104 and DT104b.

The surge in mortality and morbidity rates caused by multidrug-resistant (MDR) bacteria prompted a renewal of interest in bacteriophages (phages) as clinical therapeutics and natural biocontrol agents. Nevertheless, bacteria and phages are continually under the pressure of the evolutionary phage-host arms race for survival, which is mediated by co-evolving resistance mechanisms. In Anderson phage typing scheme of Salmonella Typhimurium, the epidemiologically related definitive phage types, DT104 and DT104b, display significantly different phage susceptibility profiles. This study aimed to characterise phage resistance mechanisms and genomic differences that may be responsible for the divergent phage reaction patterns in S. Typhimurium DT104 and DT104b using whole genome sequencing (WGS). The analysis of intact prophages, restriction-modification systems (RMS), plasmids and clustered regularly interspaced short palindromic repeats (CRISPRs), as well as CRISPR-associated proteins, revealed no unique genetic determinants that might explain the variation in phage susceptibility among the two phage types. Moreover, analysis of genes coding for potential phage receptors revealed no differences among DT104 and DT104b strains. However, the findings propose the need for experimental assessment of phage-specific receptors on the bacterial cell surface and analysis of bacterial transcriptome using RNA sequencing which will explain the differences in bacterial susceptibility to phages. Using Anderson phage typing scheme of Salmonella Typhimurium for the study of bacteria-phage interaction will help improving our understanding of host-phage interactions which will ultimately lead to the development of phage-based technologies, enabling effective infection control.

The intractum from the Eleutherococcus senticosus fruits affects the innate immunity in human leukocytes: From the ethnomedicinal use to contemporary evidence-based research.

ETHNOPHARMACOLOGICAL RELEVANCE: In the ethnomedicine of Russia, the Eleutherococcus senticosus (Rupr. et Maxim.) Maxim. fruits and roots are used to treat immune-related diseases. Because of the overexploitation of the roots, the species is considered to be endangered and is put on the Red List in some countries (e.g. the Republic of Korea). Therefore, the aerial parts of E. senticosus might be explored as a new sustainable source of compounds with an adaptogenic activity. AIM OF THE STUDY: This study is aimed to evaluate the adaptogenic activity of the Eleutherococcus senticosus fruits intractum to support the use of the fruits in folk medicine of Russia. MATERIALS AND METHODS: The effect on IL-2 and IL-10 release by peripheral blood leukocytes (PBLs) was measured by the ELISA, the CPE on the A549 and PBLs were determined with trypan blue and the MTT. The innate immunity assay was done in the VSV-PBLs model. Metabolic profiling was done using HPLC-DAD and HPLC-RID. RESULTS: We report for the first time that the intractum (300 µg/mL) and eleutheroside E (100 µg/mL) and B (100 µg/mL) do not act as a virucidal agent (VSV). The intractum and eleutherosides E and B caused the increase of the PBLs proliferation up to 24.61 and 100%, resp. The decreased viral replication in the VSV-PBLs-Int model might be associated with an increased secretion of IL-10 (328 pg/mL). Eleutheroside E and B did not affect the innate immunity. No eleutherosides were determined in the intractum, the ethyl acetate layer contained caffeic and protocatechuic acids. A large amount of myo-inositol and D-mannitol was found (267.5 and 492.5 mg/g DE). CONCLUSIONS: Our observations justify the traditional use of the fruits in Russia in immune-related diseases. The results mean that there are other compounds than eleutherosides responsible for the adaptogenic effect, probably myo-inositol and caffeic acid, for which an immunostimulatory activity has already been confirmed.

Antitumor effect of baicalin from the Scutellaria baicalensis radix extract in B-acute lymphoblastic leukemia with different chromosomal rearrangements.

Acute B-lymphoblastic leukemia (B-ALL) is the most common hematologic malignancy in children. Many cases of B-ALL harbor chromosomal translocations which are often critical determinants of prognosis. Most of them represent altered transcription factors that impact gene transcription or enhance signaling. B-ALLs harboring the mixed-lineage leukemia 1 (MLL1) gene rearrangements represent aggressive, high-risk type of early childhood leukemias that are usually associated with a very poor prognosis. Therefore, there is an urgent need for novel therapeutic agents as well as new treatment strategies. The objective was to examine the vitro inhibitory effects of Scutellaria baicalensis root extract (SBE) in B-ALL cell lines with different chromosomal rearrangements and in leukemic blasts derived from patients' bone marrow (BMCs). In this study we showed that baicalin which is the main component of the SBE possess antitumor activity against all leukemic cell lines especially those with MLL and PBX1 gene rearrangements. Baicalin inhibited cell proliferation, arrested the cell cycle at the G0/G1 phase, and induced cell death through caspase 3/7 activation. Moreover, baicalin treatment inhibited the glycogen synthase kinase-3ß (GSK-3ß) by suppressing its phosphorylation at Y216, and upregulated the downstream mediator of the cell cycle arrest - cyclin dependent kinase inhibitor p27Kip1. Bone marrow derived blasts from B-ALL patients also exhibited varied sensitivity towards baicalin with 72% patients sensitive to the SBE and baicalin treatment. Taken together, our findings provide new insights into the anti-cancer properties of baicalin by showing its diverse mode of action which might be related to the different genetic background.

New therapeutic targeting of Alzheimer's disease with the potential use of proline-rich polypeptide complex to modulate an innate immune response - preliminary study.

BACKGROUND: The lack of effective treatment for Alzheimer's disease (AD) stems mainly from the incomplete understanding of AD causes. Neuroinflammation has emerged as an important component of AD pathology, and a vast number of experimental and clinical data indicated a crucial role for the activation of the innate immune system in disease promotion and symptom progression. METHODS: Clinical examinations of AD patients in a different stage of disease severity in correlation with the measurement of two innate immune reactions, i.e., peripheral blood leukocyte (PBLs) resistance to viral infection (vesicular stomatitis virus, VSV) ex vivo, and cytokines: TNF-α, IFN-γ, IL-1ß, and IL-10, production with enzyme-linked immunosorbent assay (ELISA), have been investigated during this preliminary study before and after 4 weeks of oral treatment with dietary supplement proline-rich polypeptide complex (PRP) (120 µg of PRP/day). The potential effect of PRP on the distribution of PBLs' subpopulations has been specified. RESULTS: We have found a deficiency in innate immune response in AD patients. It was demonstrated for the first time that the degree of PBLs resistance to VSV infection was closely related to the stage of clinical severity of AD. Our study showed significant differences in cytokine production which pointed that in AD patients innate immune mechanisms are impaired. Administration of PRP to our patients increased innate immune response of PBLs and declined pro- and anti-inflammatory cytokine production, thus subduing the excessively developed inflammatory response, especially among patients with high severity of AD. PRP did not exhibit a pro-proliferative activity. It was showed, however, significant influence of PRP on the distribution of PBLs' subpopulations. CONCLUSION: The findings mentioned above might be crucial in the context of potential application of immunomodulatory therapy in AD patients and indicated PRP as a potential target for future treatments in neuroinflammatory diseases like AD.

Immune Consequences of in vitro Infection of Human Peripheral Blood Leukocytes with Vesicular Stomatitis Virus.

BACKGROUND: Oncolytic vesicular stomatitis virus (VSV) can be delivered intravenously to target primary and metastatic lesions, but the interaction between human peripheral blood leukocytes (PBLs) and VSV remains poorly understood. Our study aimed to assess the overall immunological consequences of ex vivo infection of PBLs with VSV. METHODS: Phenotypic analysis of lymphocyte subsets and apoptosis were evaluated with flow cytometry. Caspase 3/7 activity was detected by luminescence assay. Virus release was evaluated in a murine cell line (L929). Gene expression and cytokine/chemokine secretion were assessed by real-time PCR and multiplex assay, respectively. RESULTS: Ex vivo infection of PBLs with VSV elicited upregulated expression of RIG-I, MDA-5, tetherin, IFITM3, and MxA. VSV infection triggered rapid differentiation of blood monocytes into immature dendritic cells as well as their apoptosis, which depended on caspase 3/7 activation. Monocyte differentiation required infectious VSV, but loss of CD14+ cells was also associated with the presence of a cytokine/chemokine milieu produced in response to VSV infection. CONCLUSIONS: Systemic delivery is a major goal in the field of oncolytic viruses. Our results shed further light on immune mechanisms in response to VSV infection and the underlying VSV-PBL interactions bringing hope for improved cancer immunotherapies, particularly those based on intravenous delivery of oncolytic VSV.

Novel Triazole Hybrids of Betulin: Synthesis and Biological Activity Profile.

Betulin derivatives containing a 1,2,3-triazole ring possess a wide spectrum of biological activities, including antiviral, anticancer, and antibacterial activity. A series of novel triazoles were prepared by the 1,3-dipolar cycloaddition reaction between the alkyne derivatives of betulin and organic azides. The chemical structures of the obtained compounds were defined by ¹H and 13C NMR, IR, and high-resolution mass spectrometry (HR-MS) analysis. The target triazoles were screened for their antiviral activity against DNA and RNA viruses. The cytotoxic activity of the obtained compounds 5a-k and 6a-h was determined using five human cancer cell lines (T47D, MCF-7, SNB-19, Colo-829, and C-32) by a WST-1 assay. The bistriazole 6b displayed a promising IC50 value (0.05 µM) against the human ductal carcinoma T47D (500-fold higher potency than cisplatin). The microdilution method was applied for an evaluation of the antimicrobial activity of all of the compounds. The triazole 5e containing a 3'-deoxythymidine-5'-yl moiety exhibited antibacterial activity against two gram-negative bacteria vz. Klebsiellapneumoniae and Escherichia coli (minimal inhibitory concentration (MIC) range of 0.95-1.95 µM).

VSV based virotherapy in ovarian cancer: the past, the present and future?

The standard approach to treating patients with advanced epithelial ovarian cancer (EOC) after primary debulking surgery remains taxane and platinum-based chemotherapy. Despite treatment with this strategy, the vast majority of patients relapse and develop drug-resistant metastatic disease that may be driven by cancer stem cells (CSCs) or cancer initiating cells (CICs). Oncolytic viruses circumvent typical drug-resistance mechanisms, therefore they may provide a safe and effective alternative treatment for chemotherapy-resistant CSCs/CICs. Among oncolytic viruses vesicular stomatitis virus (VSV) has demonstrated oncolysis and preferential replication in cancer cells. In this review, we summarize the recent findings regarding existing knowledge on biology of the ovarian cancer and the role of ovarian CSCs (OCSCs) in tumor dissemination and chemoresistance. In addition we also present an overview of recent advances in ovarian cancer therapies with oncolytic viruses (OV). We focus particularly on key genetic or immune response pathways involved in tumorigenesis in ovarian cancer which facilitate oncolytic activity of vesicular stomatitis virus (VSV). We highlight the prospects of targeting OCSCs with VSV. The importance of testing an emerging ovarian cancer animal models and ovarian cancer cell culture conditions influencing oncolytic efficacy of VSV is also addressed.

The effects of killer cell immunoglobulin-like receptor (KIR) genes on susceptibility to HIV-1 infection in the Polish population.

Killer cell immunoglobulin-like receptors (KIR) are the most polymorphic receptors of natural killer (NK) cells. Their activity diversifies the functions of NK cells in the antiviral immune response, so the presence of certain KIR may affect transmission of HIV-1. The aim of the study was to evaluate the influence of KIR genes on the susceptibility to HIV-1 infection in the Polish population depending on the route of exposure. We determined the frequencies of activating (2DS1, 2DS2, 2DS3, 2DS4f, 2DS4del, 2DS5, 3DS1) and inhibitory (2DL1, 2DL2, 2DL3, 2DL5, 3DL1) KIRs in HIV-1-positive patients (n = 459), individuals exposed to HIV-1 but uninfected (EU, n = 118) and in uninfected, healthy blood donors (BD, n = 98). Analysis was performed using stepwise logistic regression. Apart from KIRs, CCR5-∆32, and CCR2-64I, alleles were also analyzed, as we knew or suspected that these features could affect susceptibility to HIV infection. The regression confirmed the protective effect of CCR5-∆32 (OR = 0.25, p = 0.006) and CCR2-64I (OR = 0.59, p = 0.032) against HIV infection. Among KIR genes, 2DL3 was found to be a protective factor (OR = 0.30, p = 0.015). A similar effect was seen for 3DS1 but only in intravenous drug users (IDUs) (OR = 0.30, p = 0.019), not in sexually exposed people. 2DL5 was found to be a factor facilitating HIV infection (OR = 2.13, p = 0.013). A similar effect was observed for 2DL2 but only in females (OR = 2.15, p = 0.040), and 2DS1 in IDUs (OR = 3.03, p = 0.022). Our results suggest a beneficial role of KIR3DS1 and 2DL3 supporting resistance to HIV infection and a harmful effect of 2DS1, 2DL5, and 2DL2 genes promoting HIV acquisition.

Nanoemulsion-based mucosal adjuvant induces apoptosis in human epithelial cells.

Nanoemulsions (NEs) are adjuvants that enhance antigen penetration of the nasal mucosa, increase cellular uptake of antigens by both epithelial and dendritic cells, and promote the migration of antigen-loaded dendritic cells to regional lymph nodes within 24-h of vaccine administration. The objective of this study was to elucidate cell death caused by W805EC NE and identify caspases and genes associated with death pathways. Consistent with this aim, we show that exposure of human epithelial cells (EC), both RPMI 2650 and FaDu, to NE results in the activation of caspases (1, 3/7, 6, 8, and 9) and the expression of genes involved in apoptotic as well as authophagy and necrosis pathways. Interestingly, the NE activates caspase 8 which promotes "immunogenic apoptosis". The rescue assay was employed to investigate the fate of RPMI 2650 cells treated with W805EC NE. After four-hour treatment with as little as 0.03% of NE no cells were rescued at 72h. Remarkably, immediately after four-hour treatment, the cells morphologically resembled untreated cells and most of the cells were alive. Altogether, these results suggest that NE induces death of human ECs through multiple pathways. Epithelial cell death caused by W805EC may have further implications on antigen uptake, processing, and presentation by DC's.

[Vesicular stomatitis virus (VSV) as a vaccine vector for immunization against viral infections]. / Zastosowanie wirusa pecherzykowatego zapalenia jamy ustnej (VSV) jako wektora szczepionek przeciwwirusowych.

Vesicular stomatitis virus (VSV), a member of the Rhabdoviridae family, is a promising candidate for potential use in construction of antiviral vaccines. In the natural environment VSV is a pathogen of wild ungulates and livestock. Some of the features that make VSV an excellent platform for the development of a range of viral therapeutics includes its immunogenicity and ability to grow to high titers in cell lines approved for vaccine use. Infection in humans is rare and usually asymptomatic, with mild flu-like symptoms. Moreover, due to affinity of VSV envelope glycoprotein to the LDL (low-density lipoprotein) receptor, VSV is effective at targeting a variety of tissues in vivo. A series of research results confirm the possibility of developing VSV-based vaccines against human papilloma viruses (HPV), human immunodeficiency virus (HIV), hepatitis B virus (HBV) and filoviruses (MARV, ZEBOV and SEBOV), as well as the potential use of a successfully developed vaccine against hepatitis C virus (HCV). VSV is neurotropic and infection can cause a viral encephalitis in experimental animals. Therefore, intensive studies are being undertaken to achieve satisfactory expression of the viral antigens while maintaining the safety of the constructed vectors.

Deletion of the monkeypox virus inhibitor of complement enzymes locus impacts the adaptive immune response to monkeypox virus in a nonhuman primate model of infection.

Monkeypox virus (MPXV) is an orthopoxvirus closely related to variola virus, the causative agent of smallpox. Human MPXV infection results in a disease that is similar to smallpox and can also be fatal. Two clades of MPXV have been identified, with viruses of the central African clade displaying more pathogenic properties than those within the west African clade. The monkeypox inhibitor of complement enzymes (MOPICE), which is not expressed by viruses of the west African clade, has been hypothesized to be a main virulence factor responsible for increased pathogenic properties of central African strains of MPXV. To gain a better understanding of the role of MOPICE during MPXV-mediated disease, we compared the host adaptive immune response and disease severity following intrabronchial infection with MPXV-Zaire (n = 4), or a recombinant MPXV-Zaire (n = 4) lacking expression of MOPICE in rhesus macaques (RM). Data presented here demonstrate that infection of RM with MPXV leads to significant viral replication in the peripheral blood and lungs and results in the induction of a robust and sustained adaptive immune response against the virus. More importantly, we show that the loss of MOPICE expression results in enhanced viral replication in vivo, as well as a dampened adaptive immune response against MPXV. Taken together, these findings suggest that MOPICE modulates the anti-MPXV immune response and that this protein is not the sole virulence factor of the central African clade of MPXV.

Rhesus macaque rhadinovirus-associated non-Hodgkin lymphoma: animal model for KSHV-associated malignancies.

Rhesus macaque rhadinovirus (RRV) is closely related to Kaposi sarcoma-associated herpesvirus (KSHV) and is associated with the development of B-cell hyperplasia and persistent lymphadenopathy resembling multicentric Castleman disease in rhesus macaques (RMs) coinfected with simian immunodeficiency virus (SIV). Here we investigated whether RMs experimentally infected with SIV and RRV can develop other disease manifestations observed in HIV- and KSHV-infected patients. As reported earlier, inoculation of SIV-infected RMs with RRV results in persistent RRV infection, whereas immunocompetent animals infected with RRV exhibit viremia 2 weeks after infection, followed by a period of no virus detection until they are subsequently made immunodeficient by SIV infection. A subset of animals developed abnormal cellular proliferations characterized as extranodal lymphoma and a proliferative mesenchymal lesion. In situ hybridization and immunohistochemistry analysis indicate RRV is present in both malignancies, and DNA microarray analysis detected viral interleukin-6 (vIL-6) and viral FLICE-like inhibitory protein (vFLIP) transcripts. Reverse-transcriptase polymerase chain reaction analysis confirmed vIL-6 and vFLIP expression, and that of RRV open reading frames 72 and 73, homologs of KSHV open reading frames shown to be expressed in primary effusion lymphoma. These data support the utility of the RRV-/SIV-infected RM as an excellent animal model to investigate KSHV-like pathogenesis.

Monkeypox virus viral chemokine inhibitor (MPV vCCI), a potent inhibitor of rhesus macrophage inflammatory protein-1.

Monkeypox virus (MPV) is an orthopoxvirus with considerable homology to variola major, the etiologic agent of smallpox. Although smallpox was eradicated in 1976, the outbreak of MPV in the U.S. highlights the health hazards associated with zoonotic infections. Like other orthopoxviruses, MPV encodes a secreted chemokine binding protein, vCCI that is abundantly expressed and secreted from MPV infected cells. EMSA data shows vCCI efficiently binds rhesus MIP-1alpha (rhMIP-1alpha) at near one to one stoichiometry. In vitro chemotaxis experiments demonstrate that vCCI completely inhibits rhMIP-1alpha mediated chemotaxis, while in vivo recruitment assays in rhesus macaques using chemokine-saturated implants show a decrease in the number of CD14(+) cells responding to rhMIP-1alpha when vCCI is present, suggesting vCCI is effectively inhibiting chemokine function both in vitro and in vivo. More importantly, we demonstrate that vCCI can diminish the severity of the acute phase and completely inhibit the relapsing phase of experimental allergic encephalomyelitis (EAE) disease. These data represent the first in vitro and in vivo characterization of vCCI emphasizing its function as a potent inhibitor of rhMIP-1alpha. Furthermore, the ability of vCCI to inhibit relapsing EAE disease represents a novel therapeutic approach for treating chemokine-mediated diseases.