Benralizumab: A novel treatment for the cutaneous features of paediatric eosinophilic granulomatosis with polyangiitis (pEGPA).

Eosinophilic granulomatosis with polyangiitis (EGPA) is a systemic vasculitis presenting primarily with pulmonary and cutaneous features. The disease is typically seen in the fifth or sixth decade of life (1, 2). We report a case of EGPA in an adolescent who was successfully treated with the interleukin-5 (IL-5) receptor inhibitor, benralizumab.

First Report of the Detection of 'Candidatus Liberibacter' Species in Zebra Chip Disease-Infected Potato Plants in the United States.

Zebra chip (ZC), an emerging disease causing economic losses to the potato chip industry, has been reported since the early 1990s in Central America and Mexico and in Texas during 2000 (4). ZC was subsequently found in Nebraska, Colorado, New Mexico, Arizona, Nevada, California, and Kansas (3). Severe losses to potato crops were reported in the last few years in Mexico, Guatemala, and Texas (4). Foliar symptoms include purple top, shortened internodes, small leaves, enlargement of the stems, swollen axillary buds, and aerial tubers. Chips made from infected tubers exhibit dark stripes that become markedly more visible upon frying, and hence, are unacceptable to manufacturers. Infected tubers may or may not produce plants when planted. The causal agent of ZC is not known and has been the subject of increased investigation. The pathogen is believed to be transmitted by the potato psyllid, Bactericera cockerelli, and the association of the vector with the disease is well documented (3). Following the report of a potential new liberibacter species in solanaceous crops in New Zealand, we sought to identify this liberibacter species in plants with symptoms of the ZC disease. Six potato plants (cv. Russet Norkota) exhibiting typical ZC symptoms were collected in Olton, TX in June of 2008. DNA was extracted from roots, stems, midribs, and petioles of the infected plants using a FastDNA Spin Kit and the FastPrep Instrument (Qbiogene, Inc., Carlsbad, CA). Negative controls from known healthy potato plants were included. PCR amplification was carried out with 'Candidatus L. asiaticus' omp primers (1), 16S rDNA primers specific for 'Ca. L. asiaticus', 'Ca. L. africanus', and 'Ca. L. americanus' (1), and 16S rDNA primers OA2 (GenBank Accession No. EU834130) and OI2c (2). Amplicons from 12 samples were directly sequenced in both orientations (McLab, San Francisco CA). PCR amplifications using species-specific primers for the citrus huanglongbing liberibacter were negative. However, 1.1- and 1.8-kb amplicons were obtained with the OA2/OI2C and omp primers, respectively. The sequences for the rDNA were submitted to NCBI GenBank (Accession Nos. EU884128 and EU884129). BLASTN alignment of the 16S rDNA sequences obtained with primers OA2 and OI2c revealed 99.7% identity with a new species of 'Ca. Liberibacter' identified in New Zealand affecting potato (GenBank Accession No. EU849020) and tomato (GenBank Accession No. EU834130), 97% identity with 'Ca. L. asiaticus', and 94% with 'Ca. L. africanus' and 'Ca. L. americanus'. The neighbor-joining phylogenetic tree constructed using the 16S rDNA fragments delineated four clusters corresponding to each of the liberibacter species. These results confirm that 'Ca. Liberibacter' spp. DNA sequences were obtained from potatoes showing ZC-like symptoms, suggesting that a new species of this genus may be involved in causing ZC disease. To our knowledge, this is the first report of the detection of 'Ca. Liberibacter' spp. in potatoes showing ZC disease in the United States. References: (1) C. Bastianel et al. Appl. Environ. Microbiol. 71:6473, 2005. (2) S. Jagoueix et al. Mol. Cell. Probes 10:43, 1996. (3) J. E. Munyaneza et al. J. Econ. Entomol. 100:656, 2007. (4) G. A. Secor and V. V. Rivera-Varas. Rev. Latinoamericana de la Papa (suppl.)1:1, 2004.

Two unique US isolates of Pepino mosaic virus from a limited source of pooled tomato tissue are distinct from a third (European-like) US isolate.

Three strains of Pepino mosaic virus (PepMV) found in the US have been cloned and sequenced by RT-PCR using total RNA from infected tissue as template, and degenerate potexvirus- and PepMV species- and isolate-specific primers. Despite limited source material, the complete nucleotide sequences (6413 and 6410 nts, respectively) of two isolates, PepMV-US1 and PepMV-US2, were obtained and analyzed using total RNA from less than 0.2 g of a pooled infected tomato leaf sample from Arizona. Sequence of the 3'-end of the third isolate from infected fresh tomato fruits from Maryland (PepMV-US3) was also determined. The genome organizations of PepMV-US1 and US2 were typical of the genus Potexvirus, with the following reading frame order: ORF 1, encoding a putative replicase; ORFs 2-4, triple gene block proteins (TGBp) 1-3; and ORF 5, coat protein (CP). Gene-for-gene comparison between PepMV-US1 and US2 revealed the following amino acid identities: 91% in replicase, 89% in TGBp1, 92% in TGBp2, 85% in TGBp3, and 93% in the CP; with an overall nucleotide identity of 86%. Nucleotide sequence comparisons between US1 and US2 and the European isolates showed only 79-82% identity, whereas the identity among the European isolates was over 99%. Sequence comparisons and phylogenetic analysis indicate that PepMV-US1 and US2 are distinctly different from the European isolates, while the CP of PepMV-US3 is nearly identical to the European isolates. The results presented also suggest that TGBp1 and TGBp3 are more suitable than either the replicase or coat protein gene products for discriminating PepMV isolates.

First Report of Calibrachoa mottle virus Infecting Petunia.

Calibrachoa mottle virus (CbMV), a tentative carmovirus, was first isolated and reported by Liu et al. (1) from infected Calibrachoa plants. During the spring of 2003, petunia samples from Florida and California sent to testing services at Agdia, Inc (Elkhart IN) tested positive for CbMV by enzyme-linked immunosorbent assay (ELISA) and lateral flow immunoassay (ImmunoStrips). These samples also tested positive by carmovirus group-specific polymerase chain reaction (PCR) primers and by immunocapture PCR (2). RNA extracted from these samples with the RNeasy Plant Kit (Qiagen Inc., Valencia, CA) hybridized with a digoxigenin labeled probe derived from purified CbMV viral RNA. All plant samples that tested positive for CbMV were symptomless except one symptomatic sample that also tested positive for Tobacco mosaic virus. From samples that tested positive for CbMV only, mechanical inoculations were made to Chenopodium quinoa at a USDA-ARS greenhouse in Salinas, CA. Representative single, local lesions were used to inoculate additional C. quinoa plants. The resulting local lesions from these inoculations were freeze-dried and further used as virus inoculum (CbMV petunia). Similar inoculum was made with CbMV isolated from Calibrachoa plants (CbMV calibrachoa). Virus-free Petunia hybrida cultivars Surfinia 'Baby Pink' and Surfinia 'Violet' (Jackson and Perkins Inc., Somis, CA) were mechanically inoculated with CbMV petunia and CbMV calibrachoa. Four weeks postinoculation, all plants were tested using ELISA for the presence of CbMV. In greenhouse conditions, 14.3% of 'Baby Pink' plants were positive for CbMV petunia, whereas none were positive for CbMV calibrachoa. 'Violet' plants were 64.3 and 33.3% positive for CbMV petunia and CbMV calibrachoa, respectively. None of the positive plants expressed virus-like symptoms. Virus particles resembling those of CbMV were observed from infected petunia plants with transmission electron microscopy in leaf-dip preparations. To our knowledge, this is the first report of CbMV infecting petunia. Commercial reproduction of petunia plants and maintenance of genetic mother stock are usually by vegetative propagation. CbMV can be transmitted mechanically and is readily propagated along with its host. To produce healthy petunia plants, virus-free mother stock should be used, which requires regular screening of mother stock for CbMV. Reference: (1) H.-Y. Liu et al. Plant Dis. 87:167, 2003. (2) A. M. Harness et al. (Abstr.) Phytopathology 92:S34, 2002.

First Report on the Multiplication of Tomato Spotted Wilt Tospovirus in Tobacco Thrips, Frankliniella fusca.

In Georgia, tomato spotted wilt tospovirus (TSWV) causes significant losses in peanut, tobacco, tomato, and pepper. Transmission of TSWV in Georgia primarily is by tobacco thrips (TT), Frankliniella fusca (Hinds), and western flower thrips, F. occidentalis (Pergande), with TT being the predominant vector species in peanut (2). TSWV must be acquired at the larval stage for the adult to transmit the virus. Detection of NSs (a non-structural TSWV protein present only following virus replication) in thrips by enzyme-linked immunosorbent assay (ELISA) is a reliable indicator that the virus had multiplied in the vector and thus the vector is competent to transmit TSWV. While this has been accomplished with F. occidentalis (1), information is lacking for F. fusca, the predominant vector in Georgia and other states in the Southeast. Thus, the nature of the TSWV-TT association was investigated and the proportion of transmitters in a field population determined in 1,436 individual adult TT collected from sticky cards positioned in selected peanut fields in south Georgia. Additionally, 650 larvae collected from volunteer peanut plants were reared to adults in the laboratory and the resulting 295 adult TT were individually evaluated by ELISA. Of those collected from the sticky cards, NSs was detected in 8% of the adult insects, indicating that the virus had multiplied in TT. NSs was not detected in control TT that had no access to the virus. Of the adult TT that emerged from larvae collected from volunteer peanuts, 6.1% were positive for NSs. Our study provides the first immunological evidence that TSWV multiplies in TT. References: (1) M. D. Bandla et al. Phytopathology 84:1427, 1994. (2) J. R. Chamberlin et al. J. Econ. Entomol. 86:40, 1993.

Interaction of Tomato Spotted Wilt Tospovirus (TSWV) Glycoproteins with a Thrips Midgut Protein, a Potential Cellular Receptor for TSWV.

ABSTRACT Interactions between viral and cellular membrane fusion proteins mediate virus penetration of cells for many arthropod-borne viruses. Electron microscope observations and circumstantial evidence indicate insect acquisition of tomato spotted wilt virus (TSWV) (genus Tospovirus, family Bunyaviridae) is receptor mediated, and TSWV membrane glycoproteins (GP1 and GP2) serve as virus attachment proteins. The tospoviruses are plant-infecting members of the family Bunyaviridae and are transmitted by several thrips species, including Frankliniella occidentalis. Gel overlay assays and immunolabeling were used to investigate the putative role of TSWV GPs as viral attachment proteins and deter mine whether a corresponding cellular receptor may be present in F. occidentalis. A single band in the 50-kDa region was detected with murine monoclonal antibodies (MAbs) to the TSWV-GPs when isolated TSWV or TSWV-GPs were used to overlay separated thrips proteins. This band was not detected when blots were probed with antibody to the non-structural protein encoded by the small RNA of TSWV or the TSWV nucleocapsid protein, nor were proteins from nonvector insects labeled. Anti-idiotype antibodies prepared to murine MAbs against GP1 or GP2 specifically labeled a single band at 50 kDa in Western blots and the plasmalemma of larval thrips midguts. These results support the putative role of the TSWV GPs as viral attachment proteins and identified potential cellular receptor(s) in thrips.