LMP2-DC Vaccine Elicits Specific EBV-LMP2 Response to Effectively Improve Immunotherapy in Patients with Nasopharyngeal Cancer

Objective To evaluate the safety and effectiveness of a vaccine based on latent membrane protein 2(LMP2)modified dendritic cells(DCs)that boosts specific responses of cytotoxic T lymphocytes(CTLs)to LMP2 before and after intradermal injection in patients with nasopharyngeal carcinoma(NPC).Methods DCs were derived from peripheral blood monocytes of patients with NPC.We prepared LMP2-DCs infected by recombinant adenovirus vector expressing LMP2(rAd-LMP2).NPC patients were immunized with 2×105 LMP2-DCs by intradermal injection at week 0 and after the second and fourth weeks.Specific responses to LMP2 were detected by enzyme-linked immunospot(ELISPOT)assay at week 0 and at the fifth and eighth weeks.Local clinicians performed the follow-up and tracking of patients.Results We demonstrated that DCs derived from monocytes displayed typical DC morphologies;the expression of LMP2 in the LMP2-DCs vaccine was confirmed by immunocytochemical assay.Twenty-nine patients with NPC were enrolled in this clinical trial.The LMP2-DCs vaccine was well tolerated in all of the patients.Boosted responses to LMP2 peptide sub-pools were observed in 18 of the 29 patients with NPC.The follow-up data of 29 immunized patients from April,2010 to April 2015 indicated a five-year survival rate of 94.4%in responders and 45.5%in non-responders.Conclusion In this pilot study,we demonstrated that the LMP2-DCs vaccine is safe and effective in patients with NPC.Specific CTLs responses to LMP2 play a certain role in controlling and preventing the recurrence and metastasis of NPC,which warrants further clinical testing.

Detection and Analysis of Ebola Virus in Sierra Leone-China Friendship Biosafety Laboratory from March 11 to April 20, 2015

Ebola virus disease reemerged in Western Africa in 2014.Chinese Center for Disease Control and Prevention dispatched the first Ebola virus（EBOV）detection team to run newly established Sierra Leone-China Friendship Biological Safety Laboratory.The aims of study were to understand epidemiology,clinical manifestations and survival time of EBOV in patient＇s blood.A total of 913specimens were tested between March 11 and April20, 2015. EBOV positivity occurred in 7.37% of the blood and 0.53% in throat swabs.

The Viral Load of Epstein-Barr Virus in Blood of Children after Hematopoietic Stem Cell Transplantation

Objective To detect the Epstein-Barr virus(EBV)viral load of children after hematopoietic stem cell transplantation(HSCT)using chip digital PCR(cdPCR).Methods The sensitivity of cdPCR was determined using EBV plasmids and the EBV B95-8 strain.The specificity of EBV cdPCR was evaluated using the EBV B95-8 strain and other herpesviruses(herpes simplex virus 1,herpes simplex virus 2,varicella zoster virus,human cytomegalovirus,human herpesvirus 6,and human herpesvirus 7).From May 2019 to September 2020,64 serum samples of children following HSCT were collected.EBV infection and the viral load of serum samples were detected by cdPCR.The epidemiological characteristics of EBV infections were analyzed in HSCT patients.Results The limit of detection of EBV cdPCR was 110 copies/mL,and the limit of detection of EBV quantitative PCR was 327 copies/mL for the pUC57-BALF5 plasmid.The result of EBV cdPCR was up to 121 copies/mL in the EBV B95-8 strain,and both were more sensitive than that of quantitative PCR.Using cdPCR,the incidence of EBV infection was 18.75%in 64 children after HSCT.The minimum EBV viral load was 140 copies/mL,and the maximum viral load was 3,209 copies/mL using cdPCR.The average hospital stay of children with EBV infection(184±91 days)was longer than that of children without EBV infection(125±79 days),P=0.026.Conclusion EBV cdPCR had good sensitivity and specificity.The incidence of EBV infection was 18.75%in 64 children after HSCT from May 2019 to September 2020.EBV cdPCR could therefore be a novel method to detect EBV viral load in children after HSCT.

Immunological Responses to the Combination of EBNA1 and LMP2 in Mice

Epstein-Barr virus (EBV) infection is closely associated with nasopharyngeal carcinoma (NPC)and considered one of the major risk factors[1]. A limited number of viral proteins, such as latent membrane proteins (LMP1, LMP2) and EB nuclear antigen1 (EBNA1), are expressed in NPC cells[2].Recognition epitopes for CD8+and CD4+T cells were included in the LMP2 antigen and EBNA1 C-terminal region (amino acid No. 380-641), respectively[3,4].Both CD4+and CD8+memory T-cell responses were efficiently reactivated by EBNA1 and LMP2[5;6].