BackgroundPneumococcal conjugate vaccines have been introduced in the infant immunisation programmes in many countries to reduce the rate of fatal pneumococcal infections. In the Democratic Republic of the Congo (DR Congo) a 13-valent vaccine (PCV13) was introduced in 2013. Data on the burden of circulating pneumococci among children after this introduction are lacking. In this study, we aimed to determine the risk factors related to pneumococcal carriage in healthy Congolese children after the vaccine introduction and to assess the antibiotic resistance rates and serotype distribution among the isolated pneumococci.MethodsIn 2014 and 2015, 794 healthy children aged one to 60 months attending health centres in the eastern part of DR Congo for immunisation or growth monitoring were included in the study. Data on socio-demographic and medical factors were collected by interviews with the children’s caregivers. Nasopharyngeal swabs were obtained from all the children for bacterial culture, and isolated pneumococci were further tested for antimicrobial resistance using disc diffusion tests and, when indicated, minimal inhibitory concentration (MIC) determination, and for serotype/serogroup by molecular testing.ResultsThe pneumococcal detection rate was 21%, being higher among children who had not received PCV13 vaccination, lived in rural areas, had an enclosed kitchen, were malnourished or presented with fever (p value < 0.05). The predominant serotypes were 19F, 11, 6A/B/C/D and 10A. More than 50% of the pneumococcal isolates belonged to a serotype/serogroup not included in PCV13.Eighty per cent of the isolates were not susceptible to benzylpenicillin and non-susceptibility to ampicillin and ceftriaxone was also high (42 and 37% respectively). Almost all the isolates (94%) were resistant to trimethoprim-sulphamethoxazole, while 43% of the strains were resistant to ≥3 antibiotics.ConclusionsOur study shows alarmingly high levels of reduced susceptibility to commonly used antibiotics in pneumococci carried by healthy Congolese children. This highlights the importance of local antibiotic resistance surveillance and indicates the needs for the more appropriate use of antibiotics in the area. The results further indicate that improved living conditions are needed to reduce the pneumococcal burden, in addition to PCV13 vaccination.Electronic supplementary materialThe online version of this article (10.1186/s12887-018-1332-3) contains supplementary material, which is available to authorized users.

A recombinant subunit vaccine (Shingrix®) was recently licensed for use against herpes zoster. This vaccine is based on glycoprotein E (gE) of varicella zoster virus (VZV), the most abundantly expressed protein of VZV, harboring sites for N- and O-linked glycosylation. The subunit vaccine elicits stronger virus-specific CD4+ T cell response as well as antibody B cell response to gE, compared to the currently used live attenuated vaccine (Zostavax®). This situation is at variance with the current notion since a live vaccine, causing an active virus infection, should be far more efficient than a subunit vaccine based on only one single viral glycoprotein. We previously found gE to be heavily glycosylated, not least by numerous clustered O-linked glycans, when it was produced in human fibroblasts. However, in contrast to Zostavax®, which is produced in fibroblasts, the recombinant gE of Shingrix® is expressed in Chinese hamster ovary (CHO) cells. Hence, the glycan occupancy and glycan structures of gE may differ considerably between the two vaccine types. Here, we aimed at (i) defining the glycan structures and positions of recombinant gE and (ii) identifying possible features of the recombinant gE O-glycosylation pattern contributing to the vaccine efficacy of Shingrix®. Firstly, recombinant gE produced in CHO cells (“Shingrix situation”) is more scarcely decorated by O-linked glycans than gE from human fibroblasts (“Zostavax situation”), with respect to glycan site occupancy. Secondly, screening of immunodominant B cell epitopes of gE, using a synthetic peptide library against serum samples from VZV-seropositive individuals, revealed that the O-linked glycan signature promoted binding of IgG antibodies via a decreased number of interfering O-linked glycans, but also via specific O-linked glycans enhancing antibody binding. These findings may, in part, explain the higher protective efficacy of Shingrix®, and can also be of relevance for development of subunit vaccines to other enveloped viruses.

A peculiar trait of pneumococci (Streptococcus pneumoniae) is their propensity to undergo spontaneous lysis during stationary growth due to activation of the enzyme autolysin (LytA), which fragments the peptidoglycan cell wall. The fragments that are generated upon autolysis impair phagocytosis and reduce production of interleukin-12 (IL-12) and gamma interferon (IFN-␥) by human leukocytes in response to intact pneumococci, thereby impeding crucial host defenses. The objective was to identify additional monocyte genes whose transcription is induced by intact pneumococci and subverted by autolyzed bacteria. Monocytes were isolated from healthy blood donors and stimulated for 3 h with UV-inactivated S. pneumoniae (Rx1PLY Ϫ LytA ϩ strain), which is capable of autolyzing, its LytA Ϫ isogenic autolysindeficient mutant, or a mixture of the two (containing twice the initial bacterial concentration). Gene expression was assessed by Illumina microarray, and selected findings were confirmed by reverse transcription-quantitative real-time PCR (RT-qPCR), enzyme-linked immunosorbent assay (ELISA), and flow cytometry. In all, we identified 121 genes that were upregulated to a significantly higher degree by intact than autolyzed pneumococci. These included IFNB1 and a large set of interferon-induced genes, such as IFIT3, RSAD2, CFCL1, and CXCL10 genes, as well as IL12B and CD40 genes. RT-qPCR revealed that transcription of these genes in response to intact pneumococci diminished when autolyzed pneumococci were admixed and that this pattern was independent of pneumolysin. Thus, transcription of interferon-related genes is triggered by intact pneumococci and subverted by fragments generated by spontaneous bacterial autolysis. We suggest that interferon-related pathways are important for elimination of pneumococci and that autolysis contributes to virulence by extinguishing these pathways. KEYWORDS Streptococcus pneumoniae, autolysins, inflammation, interferons Infection by the pneumococcus (Streptococcus pneumoniae) is a leading cause of death in young children worldwide (1). Pneumococci are one of the major causes of pneumonia, sepsis, and meningitis, as well as less severe localized respiratory infections, such as acute otitis media and sinusitis.The major defense against pneumococcal infection is phagocyte-mediated killing, and the most prominent virulence factor is the thick and hydrophilic pneumococcal capsule, which impedes phagocytosis. Another well-recognized virulence factor is pneumolysin, a cytolysin that incorporates into cholesterol-rich eukaryotic cell membranes. When present in high concentrations, it lyses the host cells (2), while lower

Gastrointestinal symptoms, and elevated liver enzymes, are common after HSCT, often due to drug toxicity, graft-versus-host disease (GVHD) or infections. It is essential to distinguish between GVHD and infection, since both conditions may progress to lethal disease, but require opposite strategies for the immunosuppressive treatment. Several of the viral gastrointestinal infections are easily transmitted and can cause outbreaks in health care facilities. Annika Allard för lärorikt samarbete i adenovirus-studien, och Annika Tiveljung, Mats Remberger och Mikael Sundin för samarbetet med första norovirus studien Rickard Nordén, Ebba Samuelsson, Helene Norder och Johan Westin för vårt samarbete, och allt ni lärt mig i samband med hepatit E studien Lennart Svensson och Johan Norgren, för ett roligt och bra samarbete med det senare norovirus-projektet Olle, Mona-Lisa, Mikael och Elda för vår fina gemenskap med kursen i pediatriska infektioner, och alla roliga kurs-utvärderingar hos Olle, till fantastiska måltider! Mina kollegor i "Opportunisterna" för våra väldigt trevliga möten (= terminens höjdpunkt) sedan minst 10 år tillbaka. Jag har lärt mig massor av er alla! Mina vänner, det går ofta lång tid mellan varven, men så glad att ni finns. Mina kära bröder Torbjörn, Gunnar och Janne, och mina svägerskor Christina, Sara och Johanna. För att ni är en så bra familj. Min kära mamma, för all kärlek och värme, och för din stora nyfikenhet och intresse för andra människor. Det är alltid roligt att vara med dig. Pappa, för din positiva livssyn, kärlek, och det kloka stöd du alltid gav. Jag saknar dig. Sist, men allra mest, min älskade familj, Patrik, Maj, David, Felix och Albin. För allt roligt, och för att ni är precis dom ni är.

Herpes simplex virus type 1 has the ability to induce expression of a human gene cluster located on chromosome 19 upon infection. This gene cluster contains three fucosyltransferases (encoded by FUT3, FUT5 and FUT6) with the ability to add a fucose to an N-acetylglucosamine residue. Little is known regarding the transcriptional activation of these three genes in human cells. Intriguingly, herpes simplex virus type 1 activates all three genes simultaneously during infection, a situation not observed in uninfected tissue, pointing towards a virus specific mechanism for transcriptional activation. The aim of this study was to define the underlying mechanism for the herpes simplex virus type 1 activation of FUT3, FUT5 and FUT6 transcription. The transcriptional activation of the FUT-gene cluster on chromosome 19 in fibroblasts was specific, not involving adjacent genes. Moreover, inhibition of NFκB signaling through panepoxydone treatment significantly decreased the induction of FUT3, FUT5 and FUT6 transcriptional activation, as did siRNA targeting of p65, in herpes simplex virus type 1 infected fibroblasts. NFκB and p65 signaling appears to play an important role in the regulation of FUT3, FUT5 and FUT6 transcriptional activation by herpes simplex virus type 1 although additional, unidentified, viral factors might account for part of the mechanism as direct interferon mediated stimulation of NFκB was not sufficient to induce the fucosyltransferase encoding gene cluster in uninfected cells.