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cFeline leukemia virus (FeLV) subgroups have emerged in infected cats via the mutation or recombination of the env gene of subgroup A FeLV (FeLV-A), the primary virus. We report the isolation and characterization of a novel env gene, TG35-2, and report that the TG35-2 pseudotype can be categorized as a novel FeLV subgroup. The TG35-2 envelope protein displays strong sequence identity to FeLV-A Env, suggesting that selection pressure in cats causes novel FeLV subgroups to emerge. Feline leukemia viruses (FeLVs) are pathogenic retroviruses of domestic cats (1, 2), which are classified into subgroups A (the parent virus), B, C, D, and T based on their interference and in vitro host range properties (3,4,5,6,7,8). Subgroups B and D arose from the recombination of FeLV-A env and the env genes of endogenous FeLV or endogenous retroviruses in the genomes of domestic cats (ERV-DCs) (7, 9, 10). Subgroups C and T possibly arose from mutations in FeLV-A env (11,12). The recombination or mutation of env often alters the interference and host ranges of FeLVs by affecting their receptor usage (5,6,13,14,15,16).FeLV env genes were isolated by PCR from the blood DNA of a 1-year-old castrated male cat, TG35, with a bite injury, stomatitis, loss of appetite, and FeLV infection, although he had been vaccinated with inactivated FeLV (genotype III) (16). Five clones (TG35-1 to -5) were isolated, and we focused on TG35-2, TG35-4, and TG35-5. The env sequences of these clones showed strong similarity ( Fig. 1), and the viruses clustered phylogenetically with those of genotype I/clade I FeLV, found mainly in Japan (16). The encompassing variable region A (VRA) of TG35-2 Env differs at eight amino acids from those of the TG35-4 and TG35-5 Env proteins. The proline-rich regions of TG35-2 and TG35-4, but not TG35-5, contain an inserted sequence of 25 amino acids (Fig. 1) not found in the cat genome database and of unknown origin.To identify the FeLV subgroup to which this viral strain belongs, we used an interference assay (16) and generated ␤-galactosidase (LacZ)-encoding pseudotype viruses expressing TG35-2, TG35-4, or TG35-5 envelope (Env) proteins in GPLac cells (7). Pseudotype viruses TG35-2, -4, and -5 infected uninfected HEK293T cells (Table 1). However, HEK293T cells preinfected with FeLV-A/clone 33 (293T/clone 33 cells) (17) or FeLV-A/Glasgow-1 (293T/Glasgow-1 cells) (9) were infected by pseudotype virus TG35-2, but not by TG35-4 or TG35-5. Neither cell type was infected by FeLV-A/clone 33 or FeLV-A/Glasgow-1. Therefore, only the TG35-4 and TG35-5 viruses interfered with FeLV-A. Neither the TG35-2, TG35-4, nor TG35-5 pseudotype interfered with other subgroups of FeLV, or with retroviruses such as ERV-DC10, a replication-competent feline ERV (7) ( Table 1). Therefore, FeLV TG35-4 and TG35-5 belong to the FeLV-A subgroup. However, TG35-2 could not be categorized.We next constructed a replication-competent virus (33TGE2) containing the TG35-2 env gene and the LTR, gag, and pol genes of When we examined AH927 feline cells, the TG35-2...

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The Reference Center in Japan collected 427 clinical isolates between 2008 and 2016, including 7 representative isolates from corresponding outbreaks. The collection included 419 isolates, of which 372 belonged to serogroup 1 (SG1) (87%) and the others belonged to SG2 to SG15 except for SG7 and SG11, and 8 isolates of other species (, ,, ,, and ). isolates were genotyped by sequence-based typing (SBT) and represented 187 sequence types (STs), of which 126 occurred in a single isolate (index of discrimination of 0.984). These STs were analyzed using minimum spanning tree analysis, resulting in the formation of 18 groups. The pattern of overall ST distribution among isolates was diverse. In particular, some STs were frequently isolated and were suggested to be related to the infection sources. The major STs were ST23 (35 isolates), ST120 (20 isolates), and ST138 (16 isolates). ST23 was the most prevalent and most causative ST for outbreaks in Japan and Europe. ST138 has been observed only in Japan, where it has caused small-scale outbreaks; 81% of those strains (13 isolates) were suspected or confirmed to infect humans through bath water sources. On the other hand, 11 ST23 strains (31%) and 5 ST120 strains (25%) were suspected or confirmed to infect humans through bath water. These findings suggest that some ST strains frequently cause legionellosis in Japan and are found under different environmental conditions. serogroup 1 (SG1) is the most frequent cause of legionellosis. Our previous genetic analysis indicated that SG1 environmental isolates represented 8 major clonal complexes, consisting of 3 B groups, 2 C groups, and 3 S groups, which included major environmental isolates derived from bath water, cooling towers, and soil and puddles, respectively. Here, we surveyed clinical isolates collected from patients with legionellosis in Japan between 2008 and 2016. Most strains belonging to the B group were isolated from patients for whom bath water was the suspected or confirmed source of infection. Among the isolates derived from patients whose suspected infection source was soil or dust, most belonged to the S1 group and none belonged to the B or C groups. Additionally, the U group was discovered as a new group, which mainly included clinical isolates with unknown infection sources.

Autografts and allografts are currently considered the gold standard for grafting surgery; however, to meet the growing demand in fast-aging societies, synthetic biomaterials will play an increasingly important role. Here we report a biodegradable scaffold material composed of recombinant polypeptide based on the human type I collagen alpha 1 chain (RCPhC1) as a source of hydrogel-based graft materials. The flexibility to engineer ideal characteristics for bone grafts was demonstrated. The critical internal isotropic pore structure was generated through a designed thin-layer freeze casting process. The optimized biodegradation rate was controlled by dehydrothermal crosslinking by adjusting the amino acid composition of RCPhC1. As a result, RCPhC1 bone grafts manufactured by a highly scalable streamlined production protocol induced robust regeneration of mature bone tissue while being completely resorbed in pre-clinical animal models.