In 2000, we encountered cases of nosocomial infections with epidemic keratoconjunctivitis (EKC) at a university hospital in Kobe, in the western part of Japan. Two human adenovirus (HAdV) strains, Kobe-H and Kobe-S, were isolated from patients with nosocomial EKC infection. They were untypeable by existing neutralizing antisera; however, the isolate was neutralized with homologous antisera. We then encountered several cases of EKC due to nosocomial infections in eye clinics in different parts of Japan. A total of 80 HAdVs were isolated from patients with EKC at eight different hospitals. The partial hexon gene sequences of the isolates were determined and compared to those of the prototype strains of 51 serotypes. All isolates had identical partial hexon nucleotide sequences. Phylogenetic analysis classified these isolates into species of HAdV-D. The isolates showed 93.9 to 96.7% nucleotide identity with HAdV-D prototype strains, while all 32 HAdV-D prototype strains ranged from 93.2 to 99.2% identity. The sequences of the loop 2 and fiber knob regions from the representative strain, Kobe-H, were dissimilar in all prototype strains of 51 serotypes. We believe that this virus is a novel serotype of HAdV that causes EKC.

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We determined the complete genome sequence of epidemic keratoconjunctivitis (EKC)-related human adenoviruses (HAdVs). We analysed a total of 12 HAdV strains; three prototype strains and two HAdV-8, three HAdV-19 and three HAdV-37 clinical isolates from EKC patients in Japan, and one novel serotype of HAdV. Genome organization of these serotypes was identical to those of the recently determined HAdV-19 and HAdV-37. The identities of the whole genome were over 99 % among strains from the same serotype, except for HAdV-19p, which is not associated with conjunctivitis, resulting in the formation of a distinct cluster in the phylogenetic analysis. The penton, loop 1 and loop 2 of hexon, early region 3 (E3) and fiber were hypervariable regions between serotypes. Results suggest that the HAdV-19 clinical strain is a recombinant of HAdV-19p-like and HAdV-37-like strains, and that the acquisition of the penton, E3 or fiber may be related to ocular tropism.Adenoviruses are nonenveloped, double-stranded DNA viruses with icosahedral capsids (Swenson et al., 2003). Human adenoviruses (HAdVs) belong to the genus Mastadenovirus of the family Adenoviridae and are classified into six species, A to F (HAdV-A to HAdV-F) (Benkö et al., 2000;Wold & Horwitz, 2007). Adenoviral conjunctivitis is mainly caused by HAdV-3 (in HAdV-B), HAdV-4 (in HAdV-E), and HAdV-8, , with the three HAdV-D serotypes being known to cause epidemic keratoconjunctivitis (EKC). HAdV-8 is the original causative agent of EKC and remains the predominant HAdV serotype isolated in association with EKC in many countries (Ishii et al., 1987;Chang et al., 2001;Vainio et al., 2001;Aoki & Tagawa, 2002; Jin et al., 2006). In Japan, although HAdV-8 and HAdV-19 have been described, a novel serotype of HAdV recently isolated from EKC patients and HAdV-37 are the predominant causative serotype of EKC in Japan (Higuchi et al., 1987;Aoki & Tagawa, 2002;Ishiko et al., 2008;Kaneko et al., 2008).Nucleotide polymorphisms in HAdV strains isolated from EKC patients can be classified into discrete genotypes within a specific HAdV serotype on the basis of their restriction endonuclease cleavage pattern (Wadell et al., 1980;Adrian et al., 1986). It has been speculated that the appearance of new genotypes might contribute to the incidence of outbreaks of each serotype (Aoki & Tagawa, 2002;Ariga et al., 2005). DNA sequence analysis has allowed us to appreciate the molecular evolution of HAdV in greater detail, and revealed that the penton, hexon and fiber genes were the most variable among the different serotypes (Pring-Akerblom & Adrian, 1995;Arnberg et al., 1997;Ebner et al., 2005;Madisch et al., 2005Madisch et al., , 2007 MiuraOchiai et al., 2007). The complete genome sequences of 24 HAdV serotypes 2, 3, 4, 5, 7, 9, 11, 12, 14, 16, 17, 19, 21, 26, 34, 35, 37, 40, 41, 46, 48, 49 and 50) have now been determined.In this study, we describe the complete genome sequences of the prototype strains HAdV-8p, HAdV-19p and HAdV37p together with a novel HAdV serotype and eight clinical

Purpose: To investigate the correlation between monocyte chemotactic protein-1 (MCP-1) levels in the vitreous and clinical findings in eyes with proliferative diabetic retinopathy (PDR). Methods: We assayed MCP-1 levels by ELISA in vitreous samples of 88 consecutive patients with PDR (52 eyes) and macular holes or idiopathic epimacular membrane (controls, 36 eyes). Results: The level of MCP-1 in the vitreous was 2,097.5 ± 1,099.4 pg/ml (mean ± SD) in PDR, and 504.3 ± 405.6 pg/ml in the controls. In PDR eyes, multivariate regression analysis revealed a significant association between MCP-1 levels in the vitreous and the degree of proliferative membrane, and a significant negative association between MCP-1 levels and the extent of preoperative retinal photocoagulation. Conclusion: The results suggest that MCP-1 may play a role in the development of the proliferative phase of PDR.

In a 2-month period in 2003, we encountered an outbreak of epidemic keratoconjunctivitis (EKC) in Japan. We detected 67 human adenoviruses (HAdVs) by PCR from eye swabs of patients with EKC at five eye clinics in different parts of Japan. Forty-one of the 67 HAdV DNAs from the swabs were identified as HAdV-37 by phylogenetic analysis using a partial hexon gene sequence. When the restriction patterns of these viral genomes were compared with that of the HAdV-37 prototype strain, one isolate showed a never-before-seen restriction pattern. Within 1 year, we encountered three more EKC cases caused by a genetically identical virus: two nosocomial infections at two different university hospitals and a sporadic infection at an eye clinic. We determined the nucleotide sequences of the full-length hexon and fiber genes of these isolates and compared them to those of the 51 prototype strains. Surprisingly, the sequence of the hexon ( determinant) loop-1 and -2 regions showed the highest nucleotide identity with HAdV-22, a rare EKC isolate. However, the nucleotide sequence of the fiber gene was identical to that of the HAdV-8 prototype strain. 22 We propose that this virus is a new hexon-chimeric intermediate HAdV-22,37/H8, and may be an etiological agent of EKC.