SerpinB1 is among the most efficient inhibitors of neutrophil serine proteases--NE, CG, and PR-3--and we investigated here its role in neutrophil development and homeostasis. We found that serpinB1 is expressed in all human bone marrow leukocytes, including stem and progenitor cells. Expression levels were highest in the neutrophil lineage and peaked at the promyelocyte stage, coincident with the production and packaging of the target proteases. Neutrophil numbers were decreased substantially in the bone marrow of serpinB1(-/-) mice. This cellular deficit was associated with an increase in serum G-CSF levels. On induction of acute pulmonary injury, neutrophils were recruited to the lungs, causing the bone marrow reserve pool to be completely exhausted in serpinB1(-/-) mice. Numbers of myeloid progenitors were normal in serpinB1(-/-) bone marrow, coincident with the absence of target protease expression at these developmental stages. Maturation arrest of serpinB1(-/-) neutrophils was excluded by the normal CFU-G growth in vitro and the normal expression in mature neutrophils of early and late differentiation markers. Normal absolute numbers of proliferating neutrophils and pulse-chase kinetic studies in vivo showed that the bone marrow deficit in serpinB1(-/-) mice was largely restricted to mature, postmitotic neutrophils. Finally, upon overnight culture, apoptosis and necrosis were greater in purified bone marrow neutrophils from serpinB1(-/-) compared with WT mice. Collectively, these findings demonstrate that serpinB1 sustains a healthy neutrophil reserve that is required in acute immune responses.

is the most common cause of human and canine urinary tract infection (UTI). Clonal groups, often with high levels of antimicrobial resistance, are a major component of the population that causes human UTI. While little is known about the population structure of that causes UTI in dogs, there is evidence that dogs and humans can share fecal strains of and that human-associated strains can cause disease in dogs. In order to better characterize the strains that cause canine UTI, we analyzed 295 isolates obtained from canine urine samples from five veterinary diagnostic laboratories and analyzed their multilocus sequence types, phenotypic and genotypic antimicrobial resistance profiles, and virulence-associated gene repertoires. Sequence type 372 (ST372), an infrequent human pathogen, was the predominant sequence type in dogs at all locations. Extended-spectrum β-lactamase-producing isolates with genes were uncommon in canine isolates but when present were often associated with sequence types that have been described in human infections. This provides support for occasional cross-host-species sharing of strains that cause extraintestinal disease and highlights the importance of understanding the role of companion animals in the overall transmission patterns of extraintestinal pathogenic .

Laboratory cross-sectional assays are useful for the estimation of HIV incidence, but are known to misclassify individuals with long-standing infection as recently infected. The false recent rate (FRR) varies widely across geographic areas; therefore, accurate estimates of HIV incidence require a locally defined FRR. We determined FRR for Botswana, where HIV-1 subtype C infection is predominant, using the BED capture enzyme immunoassay (BED), a Bio-Rad Avidity Index (BAI) assay (a modification of the Bio-Rad HIV1/2 + O EIA), and two multiassay algorithms (MAA) that included clinical data. To estimate FRR, stored blood samples from 512 antiretroviral (ARV)-naive HIV-1 subtype C-infected individuals from a prospective cohort in Botswana were tested at 18-24 months postenrollment. The following FRR mean (95% CI) values were obtained: BED 6.05%

Fetal tissues and placenta from a third trimester Mediterranean miniature donkey (Equus asinus) abortion were submitted to the Washington State University, Washington Animal Disease Diagnostic Laboratory for abortion diagnosis. Microscopic examination of formalin-fixed tissues revealed multifocal necrotizing placentitis. Several cells within the necrotic foci contained large, eosinophilic, intranuclear inclusions. Virus isolation from fresh, frozen placenta identified a cytopathic, syncytia-forming virus. Polymerase chain reaction (PCR) from the cultured virus using degenerate universal herpesvirus primers amplified a 699—base pair portion of the DNA polymerase gene. The PCR amplicon had 96.7% nucleotide identity with the DNA polymerase gene of Equid herpesvirus 7 (EHV-7; asinine herpesvirus 2), a gammaherpesvirus. An identical sequence was obtained when the same degenerate herpesvirus primers were used for PCR on the formalin-fixed placenta. Additionally, the amplicon had complete identity with short sequences of asinine herpesviruses that have been published in association with interstitial pneumonia in donkeys. EHV-7 has previously been isolated from nasal secretions of normal donkeys and mules. Our report describes a case of abortion associated with EHV-7 or a similar virus.