Microbial targets for protective humoral immunity are typically surface-localized proteins and contain common sequence motifs related to their secretion or surface binding. Exploiting the whole genome sequence of the human bacterial pathogen Streptococcus pneumoniae, we identified 130 open reading frames encoding proteins with secretion motifs or similarity to predicted virulence factors. Mice were immunized with 108 of these proteins, and 6 conferred protection against disseminated S. pneumoniae infection. Flow cytometry confirmed the surface localization of several of these targets. Each of the six protective antigens showed broad strain distribution and immunogenicity during human infection. Our results validate the use of a genomic approach for the identification of novel microbial targets that elicit a protective immune response. These new antigens may play a role in the development of improved vaccines against S. pneumoniae.Streptococcus pneumoniae (the pneumococcus) is the leading cause of bacterial sepsis, pneumonia, meningitis, and otitis media in young children in the United States. Annually, 7,000,000 middle-ear infections are ascribed to this organism (4). The vaccines in current use are formulations of capsular carbohydrate from the 23 serotypes responsible for 85 to 90% of infections in the United States, but these vaccines are poorly efficacious in infants and the elderly, the populations that are most at risk (1). A heptavalent-capsular-carbohydrate vaccine conjugated to the protein carrier CRM197 has been shown to be well tolerated and efficacious against invasive disease caused by the seven vaccine serotype strains (3) and has recently been approved for use in young children. However, this type of vaccine has several potential limitations, including serotype replacement by strains that are not represented (14).The advent of whole-genome sequencing of microbes, including microbial pathogens, has revolutionized the methods by which these organisms are studied and has heightened expectations regarding the ability to predict potential targets for antimicrobial agents and vaccines (2,12,20). We combined sequence scanning for prediction of surface-localized proteins with an animal model which allowed us to directly screen proteins for vaccine efficacy to identify novel vaccine candidates from the genome sequence of S. pneumoniae. Here we describe the use of a clinically relevant animal model for the evaluation of the vaccine efficacy of proteins identified from the genome sequence of pneumococcus. This approach was validated by the discovery of five previously unidentified genes whose products induced immune responses that protected mice from pneumococcal infection. Similar sequence scanning methods were recently used to identify potential vaccine candidates from the genomic sequence of the gram-negative pathogen Neisseria meningitidis (21) predicted by in vitro correlates of vaccine effectiveness. Here we expand upon the use of genomics to directly demonstrate vaccine efficacy in an animal model for...

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Balugrastim is a once-per-cycle, fixed-dose recombinant protein comprising human serum albumin and granulocyte colony-stimulating factor under development for prevention of severe neutropenia in cancer patients receiving myelosuppressive chemotherapy. This phase II, multicenter, active-controlled, dose-finding pilot study evaluated balugrastim safety and efficacy versus pegfilgrastim in breast cancer patients scheduled to receive myelosuppressive chemotherapy and investigated two doses with similar efficacy to pegfilgrastim for a subsequent phase III study. Patients received four cycles of doxorubicin/docetaxel chemotherapy and with each successive cycle were randomized sequentially to escalating doses of balugrastim [30 (n = 11), 40 (n = 21), or 50 mg (n = 20)] or a fixed dose of pegfilgrastim [6 mg (n = 26)] post-chemotherapy. Balugrastim doses were escalated as planned. The incidence of adverse events was similar among the balugrastim groups and between all balugrastim doses and pegfilgrastim. The most frequently reported adverse events were neutropenia, alopecia, and nausea. During cycle 1, severe neutropenia (absolute neutrophil count of <0.5 × 10(9)/L) occurred in 40, 67, and 50 % and febrile neutropenia occurred in 20.0, 9.5, and 10.0 % of patients receiving balugrastim 30, 40, and 50 mg, respectively; in patients receiving pegfilgrastim, 48 % experienced severe neutropenia and 8 % experienced febrile neutropenia. Duration of severe neutropenia (DSN) for each treatment group was 0.9, 1.6, 1.1, and 0.9 days, respectively. In the remaining three chemotherapy cycles, DSN was ≤1 day across all treatment groups. Balugrastim 50 mg was comparable to pegfilgrastim in terms of safety and overall efficacy in breast cancer patients receiving myelosuppressive chemotherapy.

The malignant Reed-Sternberg cell of Hodgkin’s disease, first described a century ago, has resisted in-depth analysis due to its extreme rarity in lymphomatous tissue. To directly study its genome-wide gene expression, approximately 11,000,000 bases (27,518 cDNA sequences) of expressed gene sequence was determined from living single Reed-Sternberg cells, Hodgkin’s tissue, and cell lines. This approach increased the number of genes known to be expressed in Hodgkin’s disease by 20-fold to 2,666 named genes. The data here indicate that Reed-Sternberg cells from both nodular sclerosing and lymphocyte predominant Hodgkin’s disease were derived from an unusual B-cell lineage based on a comparison of their gene expression to approximately 40,000,000 bases (105 sequences) of expressed gene sequence from germinal center B cells (GCB) and dendritic cells. The data set of expressed genes, reported here and on the World Wide Web, forms a basis to understand the genes responsible for Hodgkin’s disease and develop novel diagnostic markers and therapies. This study of the rare Reed-Sternberg cell, concealed in its heterogenous cellular context, also provides a formidable test case to advance the limit of analysis of differential gene expression to the single disease cell.