Proteins usually associate with other molecules physically to execute their functions. Identifying these interactions is important for the functional analysis of proteins. Previously, we reported the parallel analysis of translated ORFs (PLATO) to couple ribosome display of full-length ORFs with affinity enrichment of mRNA/protein/ribosome complexes for the "bait" molecules, followed by the deep sequencing analysis of mRNA. However, the sample processing, from extraction of precipitated mRNA to generation of DNA libraries, includes numerous steps, which is tedious and may cause the loss of materials. Barcoded PLATO (PLATO-BC), an improved platform was further developed to test its application for protein interaction discovery. In this report, we tested the antisera-antigen interaction using serum samples from patients with inclusion body myositis (IBM). Tripartite motif containing 21 (TRIM21) was identified as a potentially new IBM autoantigen. We also expanded the application of PLATO-BC to identify protein interactions for JQ1, single ubiquitin peptide, and NS5 protein of Zika virus. From PLATO-BC analyses, we identified new protein interactions for these "bait" molecules. We demonstrate that Ewing sarcoma breakpoint region 1 (EWSR1) binds to JQ1 and their interactions may interrupt the EWSR1 association with acetylated histone H4. RIO kinase 3 (RIOK3), a newly identified ubiquitin-binding protein, is preferentially associated with K63-ubiquitin chain. We also find that Zika NS5 protein interacts with two previously unreported host proteins, par-3 family cell polarity regulator (PARD3) and chromosome 19 open reading frame 53 (C19orf53), whose attenuated expression benefits the replication of Zika virus. These results further demonstrate that PLATO-BC is capable of identifying novel protein interactions for various types of "bait" molecules.

OBJECTIVETo explore the risk factors, and control measures of cytomegalovirus (CMV) infection after hematopoietic stem cell transplantion (HSCT) in children with primary immunodeficiency diseases(PID).

METHODSWe retrospectively analyzed results of 26 patients with PID-Wiskott-Aldrich syndrome (WAS, n=20), severe combined immunodeficiency (SCID, n=1) , X-linked chronic granulomatous disease (XCGD, n=2) and X-linked hyper-immunoglobulin M (IgM) syndrome (XHIM, n=3)-who underwent HSCT from June 2007 to December 2012 in our center. Serologic studies (ELISA) and weekly CMV infection surveillance (quantitative PCR, qPCR) were routinely performed before and after HSCT. Ganciclovir or forcarnet was used for pre-emptive and curative therapy.

RESULTSAll 26 patients were male with the median age at HSCT of 27 months (range 7-77 months). At a median follow up of 24 months (range 5-66 months), the 5-year overall survival rate was (75.0 ± 9.0) %. CMV infection occurred in 42.3% (11 of 26) of the patients, two of them developed CMV interstitial pneumonia (CMVIP). Univariate analysis revealed that the incidence of pre-transplant CMV infection between with and without CMV activation groups after HSCT was significantly different (62.5% vs 10.0%, P=0.010). Additional variables not associated with CMV infection were stem-cell sources, donor type, HLA disparity and acute GVHD (all P values>0.05).

CONCLUSIONCMV infection was a major complication of HSCT. Sensitive monitoring, early diagnosis, timely treatment may improve the survival rate for these PID undergoing HSCT.

Child ; Child, Preschool ; Cytomegalovirus Infections ; virology ; Graft vs Host Disease ; Granulomatous Disease, Chronic ; therapy ; Hematopoietic Stem Cell Transplantation ; adverse effects ; Humans ; Infant ; Male ; Retrospective Studies ; Risk Factors ; Severe Combined Immunodeficiency ; therapy ; Tissue Donors ; Wiskott-Aldrich Syndrome ; therapy