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See the Editorial commentary by Miller on pages 191-2.) Background. The incidence of herpes zoster is up to 9 times higher in immunosuppressed solid organ transplant recipients than in the general population. We investigated the immunogenicity and safety of an adjuvanted recombinant zoster vaccine (RZV) in renal transplant (RT) recipients ≥18 years of age receiving daily immunosuppressive therapy. Methods. In this phase 3, randomized (1:1), observer-blind, multicenter trial, RT recipients were enrolled and received 2 doses of RZV or placebo 1-2 months (M) apart 4-18M posttransplant. Anti-glycoprotein E (gE) antibody concentrations, gE-specific CD4 T-cell frequencies, and vaccine response rates were assessed at 1M post-dose 1, and 1M and 12M post-dose 2. Solicited and unsolicited adverse events (AEs) were recorded for 7 and 30 days after each dose, respectively. Solicited general symptoms and unsolicited AEs were also collected 7 days before first vaccination. Serious AEs (including biopsy-proven allograft rejections) and potential immune-mediated diseases (pIMDs) were recorded up to 12M post-dose 2. Results. Two hundred sixty-four participants (RZV: 132; placebo: 132) were enrolled between March 2014 and April 2017. gE-specific humoral and cell-mediated immune responses were higher in RZV than placebo recipients across postvaccination time points and persisted above prevaccination baseline 12M post-dose 2. Local AEs were reported more frequently by RZV than placebo recipients. Overall occurrences of renal function changes, rejections, unsolicited AEs, serious AEs, and pIMDs were similar between groups. Conclusions. RZV was immunogenic in chronically immunosuppressed RT recipients. Immunogenicity persisted through 12M postvaccination. No safety concerns arose. clinical Trials Registration. NCT02058589.

Restricted to the genus Streptococcus, the Pht protein family comprises four members: PhtA, PhtB, PhtD and PhtE. This family has the potential to provide a protein candidate for incorporation in pneumococcal vaccines. Based on sequence analysis and on RT-PCR experiments, we show here that the pht genes are organized in tandem but that their expression, except that of phtD, is monocistronic. PhtD, PhtE, PhtB and PhtA are present in 100, 97, 81 and 62 % of the strains, respectively, and, by analysing its sequence conservation across 107 pneumococcal strains, we showed that PhtD displays very little variability. To analyse the physiological function of these proteins, several mutants were constructed. The quadruple Pht-deficient mutant was not able to grow in a poor culture medium, but the addition of Zn 2+ or Mn 2+ restored its growth capacity.Moreover, the phtD mRNA expression level increased when the culture medium was depleted in zinc. Therefore, we suggest that these proteins are zinc and manganese scavengers, and are able to store these metals and to release them when the bacterium faces an ion-restricted environment. The data also showed that this protein family, and more particularly PhtD, is a promising candidate to be incorporated into pneumococcal vaccines.

; on behalf of the Zoster-028 Study Group BACKGROUND: The adjuvanted recombinant zoster vaccine (RZV) has demonstrated >90% efficacy against herpes zoster in adults ≥50 years of age and 68% efficacy in autologous hematopoietic stem cell transplant recipients ≥18 years of age. We report the immunogenicity and safety of RZV administered to patients with solid tumors (STs) before or at the start of a chemotherapy cycle. METHOD: In this phase 2/3 observer-blind, multicenter study (NCT01798056), patients with STs who were ≥18 years of age were randomized (1:1) to receive 2 doses of RZV or placebo 1-2 months apart and stratified (4:1) according to the timing of the first dose with respect to the start of a chemotherapy cycle (first vaccination 8-30 days before the start or at the start [±1 day] of a chemotherapy cycle). Anti-glycoprotein E (gE) antibody concentrations, gE-specific CD4 + T cell frequencies, and vaccine response rates (VRRs) were assessed 1 month after dose 1 and 1 and 12 months after dose 2. Reactogenicity and safety were assessed in the total vaccinated cohort through 12 months after dose 2. RESULTS: There were 232 participants in the total vaccinated cohort, 185 participants in the according-to-protocol cohort for humoral immunogenicity, and 58 participants in the according-to-protocol cohort for cell-mediated immunogenicity. Postvaccination anti-gE antibody concentrations, gE-specific CD4 + T cell frequencies and VRRs were higher in RZV recipients than in placebo recipients. Solicited adverse events (AEs) were more frequent among RZV recipients than placebo recipients. Incidence of unsolicited AEs, serious AEs, fatalities, and potential immune-mediated diseases were similar between RZV and placebo recipients. CONCLUSION: RZV was immunogenic in patients with STs receiving immunosuppressive chemotherapies. Humoral and cell-mediated immune responses persisted 1 year after vaccination. No safety concerns were identified.

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C263-6) were able to bind poorly '"I-secretin, and to activate adenylate cyclase with high secretin EC,, values. These results suggest that cysteine residues 24,44, 53, 67, 85 and 101 are necessary for receptor function, and that the two putative disulfide bridges formed by cysteine residues 11, 186, 193 and 263 are functionally relevant, but not essential for receptor expression. Secretin activated the adenylate cyclase through the quadruple mutant (C11,186,193,263-S), the four triple mutants, and through double mutants C186,193-S and C186,263+S with a very high (pM) EC,, value, suggesting that, in the wild-type receptor, disulfide bridges are formed between C11 -C186, and between C193-C263. Prior treatment with dithiothreitol resulted in a marked EC,,, increase of the wild-type receptor and of those receptors with at least the two cysteine residues in positions 11 and 186, suggesting that the Cll-C186 (but not the C193-C263) disulfide bridge was accessible to this reducing agent. Several results nevertheless indicated that, in mutant receptors, alternative disulfide bridges can be formed between cysteine 186 and cysteine 193 or 263, suggesting that these three residues are in close spatial proximity in the wild-type receptor.Keywords: secretin receptor; cysteine ; point-mutation ; disulfide bridge. Despite the low overall sequence similarity in the extracellular part of the secretin receptor family, a conserved pattern of extracellular cysteine residues is one of their primary characteristics; usually, five to seven cysteine residues are present in the amino-terminal extracellular domain, as well as one in each of the first two extracellular loops. Fig. 1 indicates the localisation of the extracellular cysteine residues of the secretin receptor: seven residues in the amino-terminal tail, and three in the extracellular loops. Cysteine residues 44, 53, 67 and 8. 5 in the Nterminal tail and 193 and 263 in the exoloop 1 and 2, respectively, are strictly conserved in the secretin-receptor family. Moreover, Cys193 and Cys263 are highly conserved in all the members of the G-protein-coupled seven-transmembrane-helices family of receptors, with the exception of the human mas oncogene [19] and of the rat cannabinoid receptor [20].In order to determine whether the extracellular cysteine residues of the secretin receptor are involved in disulfide bridges and to define the contribution of these linkages to receptor occupancy and agonist activation, we replaced one or several codons encoding Cys residues by codons for Ser residues and stably expressed the mutant receptors in CHO cells. We assumed that the effect of Cys-Ser mutation is limited to the elimination of the disulfide bond which involved that Cys residue, so that mutation of either or both Cys involved in a given disulfide bond should result in receptor mutants with the same pharmacological properties.The results, based on ligand-binding studies, adenylate cyclase assays, and the effect of a prior treatment with a reducing agent are consistent with the existence o...

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