Immunogenicity and safety of 7-valent pneumococcal conjugate vaccine (PCV7) in children aged 2-5 years in China.

BACKGROUND: The widespread use of pneumococcal conjugate vaccines (PCVs) has significantly decreased pneumococcal disease worldwide. However, China has not adopted PCVs in their national immunization schedules and had only approved these vaccines for children aged 2-15 months by 2020. METHODS: In an open-label trial, enrolled healthy children aged 2-5 years old were randomized 1:1 and divided into a 7-valent pneumococcal conjugate vaccine (PCV7) group and a Haemophilus influenzae type b conjugate vaccine (Hib) group. Children in the PCV7 group received a single dose of PCV7, and the Hib group received a single dose of Hib vaccine. Blood samples were collected before and 6 months after vaccination. Immunogenicity and safety of PCV7 were assessed at prespecified time points. RESULTS: Six months after a single dose of PCV7, children in the PCV7 group for all 7 serotypes, IgG mean concentrations (GMCs) and opsonophagocytic geometric mean titres (GMTs) were significantly higher (P < .001) than at baseline, and the proportion of IgG ≥ 0.35 µg/mL ranged from 90.0% to 100%. Although the antibody level increased with age, preexisting antibodies did not induce hyporesponsiveness to PCV7. In the Hib group, the antibody levels were not significantly different or had changed slightly at 6 months. PCV7 was well tolerated in all age groups, and no serious adverse events (AEs) emerged during this study. CONCLUSIONS: A single dose of PCV7 was immunogenic and safe for Chinese children aged 2-5 years, and the preexisting antibodies against the PCV7 serotypes did not change the response to vaccination. The findingssupported the effectiveness of PCV7 in this age group. PCVs with broader serotype coverage are expected to expand pneumococcal disease protection.

Regulation of Drosophila Hematopoiesis in Lymph Gland: From a Developmental Signaling Point of View.

The Drosophila hematopoietic system is becoming increasingly attractive for its simple blood cell lineage and its developmental and functional parallels with the vertebrate system. As the dedicated organ for Drosophila larval hematopoiesis, the lymph gland harbors both multipotent stem-like progenitor cells and differentiated blood cells. The balance between progenitor maintenance and differentiation in the lymph gland must be precisely and tightly controlled. Multiple developmental signaling pathways, such as Notch, Hedgehog, and Wnt/Wingless, have been demonstrated to regulate the hematopoietic processes in the lymph gland. Focusing on blood cell maintenance and differentiation, this article summarizes the functions of several classic developmental signaling pathways for lymph gland growth and patterning, highlighting the important roles of developmental signaling during lymph gland development as well as Drosophila larval hematopoiesis.

Antibacterial and Antitumor Potential of Actinomycetes Isolated from Mangrove Soil in the Maowei Sea of the Southern Coast of China.

Mangroves are the tidal forest existing in the intertidal zone and usually considered as the special marine ecosystem. In the present study, 452 actinomycetes were recovered from nine diferent sites at Maowei Sea Mangrove Reserve in Qinzhou (Guangxi province, China). Among them, Seventy-four strains were purified for 16s RNA gene sequencing and further characterization. The results indicated that the majority of isolates belonged to the genera Streptomyces, including 17 species. Streptomyces sanyensis was the dominant species (31.1%), followed by Streptomyces griseorubens (17.5%), Streptomyces viridobrunneus (10.8%) and other Streptomyces species. Only one rare actinomycete, Stenotrophomonas was discovered. The isolation of actinomycetes was obviously related to the type of soil and edaphic conditions. Rhizosphere-associated soils gave almost 62.2% actinomycete isolates, nearly twice as many as the non-rhizosphere-associated soils. In addition, 20 actinomycete strains (27%) presented varied antibacterial activities towards four tested organisms, including two drug-resistant clinical strains (MRSA and VRE), while some species of Streptomyces like S.sanyensis, S.viridobrunneus, S.tanashiensis, S.parvus, S.flavotricini, and S.parvulus exhibited remarkable cytotoxic activities. Further bioinformatical analysis of these 29 bioactive strains for secondary metabolites biosynthetic machineries revealed that nonribosomal peptide synthetase (NRPS) was detected in 20 isolates (68.9%), whereas type-I polyketide synthase (PKS-I) and type-II polyketide synthase (PKS-II) were detected in 16 and all of the 29 strains, respectively. Hence, our work demonstrated that actinomycetes from mangroves in Maowei Sea Mangrove Reservewere fascinating reservoirs for antibacterial and antitumor natural products discovery.

PpV, acting via the JNK pathway, represses apoptosis during normal development of Drosophila wing.

Apoptosis is one of the main fundamental biological processes required for development of multicellular organisms. Inappropriate regulation of apoptosis can lead to severe developmental abnormalities and diseases. Therefore, the control of apoptosis, not only for its activation but also for its inhibition, is critically important during development. In contrast to the extensive studies of apoptosis induction, its inhibitory mechanisms that are even more vital in certain populations of cells actually are very far from being well understood. Here we report an inhibitory role of protein phosphatase V (PpV), a serine/threonine protein phosphatase, in controlling the apoptosis during Drosophila wing development. We observed that inhibition of ppv by RNAi in wing imaginal discs induced ectopic cell death and caspase activation, thus, resulted in a defective adult wing. Moreover, knocking-down ppv triggered the activation of c-Jun N-terminal kinase (JNK) signal, an evolutionarily conserved intracellular signaling that has been implicated to modulate the apoptotic machinery in many biological and experimental systems. Disrupting the JNK signal transduction was adequate to suppress the ppv effects for wing development. Together, we provided the evidence to demonstrate that ppv is required for normal wing development in maintaining the silence of apoptotic signal possibly through JNK pathway.

The emerging roles of phosphatases in Hedgehog pathway.

Hedgehog signaling is evolutionarily conserved and plays a pivotal role in cell fate determination, embryonic development, and tissue renewal. As aberrant Hedgehog signaling is tightly associated with a broad range of human diseases, its activities must be precisely controlled. It has been known that several core components of Hedgehog pathway undergo reversible phosphorylations mediated by protein kinases and phosphatases, which acts as an effective regulatory mechanism to modulate Hedgehog signal activities. In contrast to kinases that have been extensively studied in these phosphorylation events, phosphatases were thought to function in an unspecific manner, thus obtained much less emphasis in the past. However, in recent years, increasing evidence has implicated that phosphatases play crucial and specific roles in the context of developmental signaling, including Hedgehog signaling. In this review, we present a summary of current progress on phosphatase studies in Hedgehog pathway, emphasizing the multiple employments of protein serine/threonine phosphatases during the transduction of morphogenic Hedgehog signal in both Drosophila and vertebrate systems, all of which provide insights into the importance of phosphatases in the specific regulation of Hedgehog signaling.