In situ tumor vaccination with adenovirus vectors encoding measles virus fusogenic membrane proteins and cytokines

AIM： To evaluate whether intratumoral expression of measles virus fusogenic membrane glycoproteins H and F （MV-FMG）, encoded by an adenovirus vector Ad.MV-HI F, alone or in combination with local coexpression of cytokines （IL-2, IL-12, IL-18, IL-21 or GM-CSF）, can serve as a platform for inducing tumor-specific immune responses in colon cancer.METHODS： We used confocal laser scanning microscopy and flow cytometry to analyze cell-cell fusion after expression of MV-FMG by dye colocalization. In a syngeneic bilateral subcutaneous MC38 and Colon26 colon cancer model in C57BL/6 and BALB/c mice, we assessed the effect on both the directly vector-treated tumor as well as the contralateral, not directly vector- treated tumor. We assessed the induction of a tumorspecific cytotoxic T lymphocyte （CTL） response with a lactate dehydrogenase （LDH） release assay.RESULTS： We demonstrated in vitro that transduction of MC38 and Colon26 cells with Ad.MV-H/F resulted in dye colocalization, indicative of cell-cell fusion, in addition, in the syngeneic bilateral tumor model we demonstrated a significant regression of the directly vector-inoculated tumor upon intratumoral expression of MV-FMG alone or in combination with the tested cytokines. We observed the highest anti-neoplastic efficacy with MV-FMG and lL-21 coexpression. The degree of tumor regression of the not directly vector-treated tumor correlated with the anti-neoplastic response of the directly vector-treated tumor. This regression was mediated by a tumor-specific CTL response.CONCLUSION： Our data indicate that intratumoral expression of measles virus fusogenic membrane glycoproteins is a promising tool both for direct tumor treatment as well as for tumor vaccination approaches that can be further enhanced by cytokine coexpression.

Isolation and Complete Nucleotide Sequence of the Measles Virus IMB-1 Strain in China

The complete nucleotide sequence of the measles virus strain IMB-1,which was isolated in China,was determined.As in other measles viruses,its genome is 15,894 nucleotides in length and encodes six proteins.The full-length nucleotide sequence of the IMB-1 isolate differed from vaccine strains (including wild-type Edmonston strain) by 4%-5% at the nucleotide sequence level.This isolate has amino acid variations over the full genome,including in the hemagglutinin and fusion genes.This report is the first to describe the full-length genome of a genotype H1 strain and provide an overview of the diversity of genetic characteristics of a circulating measles virus.

Carrier Cells for Delivery of Oncolytic Measles Virus into Tumors：Determinants of Efficient Loading

Oncolytic measles virus(OMV) is a promising antitumor agent. However, the presence of anti-measles neutralizing antibodies(NAbs) against the hemagglutinin(H) protein of OMV is a major barrier to the therapeutic application of OMV in clinical practice. In order to overcome this challenge, specific types of cells have been used as carriers for OMV.Differential loading strategies appear to result in different therapeutic outcomes; despite this, only few studies have reported practical ex vivo loading strategies required for effective treatment. To this end, we systematically evaluated the antitumor efficacy of OMV using different loading strategies; this involved varying the in vitro loading duration and loading dose of OMV. We found that improved oncolysis of carrier cells was achieved by a prolonged loading duration in the absence of NAbs. However, the enhanced oncolytic effect was abrogated in the presence of NAbs. Further, we found that the expression of H protein on the surface of carrier cells was predominantly determined by the loading duration rather than the loading dose. Finally, we showed that NAbs blocked viral transfer by targeting H protein prior to the occurrence of cell-to-cell interactions. Our results provide comprehensive information on the determinants of an effective loading strategy for carrier cell-based virotherapy; these results may be useful for guiding the application of OMV as an antitumor agent in clinical practice.

Measles virus hemagglutinin triggers intracellular signaling in CD150-expressing dendritic cells and inhibits immune response

Measles virus （MV） is highly contagious pathogen, which causes a profound immunosuppression, resulting in high infant mortality. This virus infects dendritic cells （DCs） following the binding of MV hemagglutinin （MV-H） to CD150 receptor and alters DC functions by a mechanism that is not completely understood. We have analyzed the effect of MV-H interaction with CD150-expressing DCs on the DC signaling pathways and consequent phenotypic and functional changes in the absence of infectious context. We demonstrated that contact between CD150 on human DCs and MV-H expressed on membrane of transfected CHO cells was sufficient to modulate the activity of two major regulatory pathways of DC differentiation and function： to stimulate Akt and inhibit p38 MAPK phosphorylation, without concomitant ERK1/2 activation. Furthermore, interaction with MV-H decreased the expression level of DC activation markers CD80, CD83, CD86, and HLA-DR and strongly downregulated IL-12 production but did not modulate IL-IO secretion. Moreover, contact with MV-H suppressed DC-mediated T-cell alloproliferation, demonstrating profound alteration of DC maturation and functions. Finally, engagement of CD150 by MV-H in mice transgenic for human CD150 decreased inflammatory responses, showing the immunosuppressive effect of CD150-MV-H interaction in vivo. Altogether, these results uncover novel mechanism of MV-induced immunosuppression, implicating modulation of cell signaling pathways following MV-H interaction with CD150-expressing DCs and reveal anti-inflammatory effects of CD150 stimulation.

Measles Virus(Nepal Strain)Hemagglutinin Gene: Cloning,Complete Nucleotide Sequence Analysis and Expression in COS Cells

Hemagglutinin gene of Measles virus(Nepal strain) was amplified by RT PCR technique, cloned and sequenced by the dideoxy mediated chain termination method. The comparison to the standard strain(Edmonston strain) showed many important mutations. The homology of these two strains was 98.17%. Then H gene was cloned into expression vector pCD SRα296 and introduced into COS 7 cells by electroporation method. The expression and function of cloned H gene was checked by hemadsorption assays.

Viral co-infections among children with confirmed measles at hospitals in Hanoi,Vietnam,2014

Objective:To characterize viral co-infections among representative hospitalized measles cases during the 2014 Hanoi outbreak.Methods:Throat swabs were collected from 54 pediatric patients with confirmed measles,and molecular diagnostics performed for 10 additional viral respiratory pathogens(Influenza A/H1N1pdm09;A/H3N2 and influenza B;Parainfluenza 1,2,3;Respiratory Synctial Virus,RSV;human Metapneumovirus,hM PV;Adenovirus and Picornavirus).Results:Twenty-one cases(38.9%) showed evidence of infection with other respiratory viruses:15 samples contained measles plus one additional virus,and 6 samples contained measles plus 2 additional viruses.Adenovirus was detected as a predominant cause of co-infections(13 cases;24.1%),followed by RSV(6 cases;11.1%),A/H1N1pdm09(3 cases;5.6%),PIV3(3 cases;3.7%),Rhinovirus(3 cases;3.7%) and hM PV(1 case;1.96%).Conclusions:Viral co-infections identified from pediatric measles cases may have contributed to increased disease severity and high rate of fatal outcomes.Optimal treatment of measles cases may require control of multiple viral respiratory pathogens.

Oncolytic viruses:A novel treatment strategy for breast cancer

Breast cancer,an unceasingly occurring neoplasm,is one of the major determinants of mortality in women.Several ineffective attempts have been pursued using with conventional therapies against breast cancer.Resistance to existing therapies and their respective debilitating adverse effects have led research toward a new era of cancer treatment using viruses.Virotherapy constitutes a developing treatment modality with multiple mechanisms of therapeutic activity in which the viruses can be directly oncolyticand can express transgenes or induce host immune response against tumor cells.Several different DNA-and RNA-containing viruses have been considered for virotherapy of breast cancer including adenovirus,herpes virus,vaccinia,reovirus,Newcastle Disease virus,measles virus and vesicular stomatitis virus.This review aims to summarize the viro-therapeutical agents against breast malignancies.Key Scientific Concepts of Review:In this review paper,we proposed a new strategy to virus's combinatorial treatments using several kinds of transgenes and drugs.These recombinant viruses have provided evidence of treatment efficacy against human breast cancer.