Meningoencephalitis in mice infected with an equine herpesvirus 1 strain KyA recombinant expressing glycoprotein I and glycoprotein E.

One of the consequences of equine herpesvirus 1 (EHV-1) infection in the natural host is a neurological disease that can lead to paralysis. The pathology associated with EHV-1-induced neurological disease includes vasculitis of the small blood vessels within the central nervous system and subsequent damage to the surrounding neural tissue. In a previous study, an EHV-1 recombinant KyA virus (KgI/gE/75) was generated in which the sequences encoding glycoprotein I (gI) and glycoprotein E (gE) were repaired [Frampton et al. 2002 (Virus Research 90: 287-301)] using genes of the pathogenic EHV-1 strain 89c25. In contrast to the parental KyA virus that lacks gI and gE, the recombinant KgI/gE/75 was able to spread to the brains of CBA mice after intranasal infection. Infection resulted in a meningoencephalitis characterized by lymphocytic cuffing of small blood vessels within the brain, consistent with that observed in EHV-1-infected horses exhibiting neurological signs. KgI/gE/75 was able to elicit cytopathology in the lung prior to spread to the brain. However, like the attenuated KyA strain, KgI/gE/75 did not persist in the lung and was completely cleared from lung tissue by day 5 postinfection. We propose that gI and gE are neurovirulence factors for EHV-1, and that the CBA mouse model can be extended to study neurologic sequelae resulting after EHV-1 infection.

Litigation cells: their incidence and classification in gynecologic smears.

"Litigation cells" are defined as benign cells which may mimic dysplasia or cancer and might be used by plaintiffs' witnesses to imply that the cytotechnologist or pathologist "missed" cells of dysplasia or cancer. We reviewed 180 cervical smears from 166 patients who had hysterectomy for benign leiomyomas. All smears were performed within 12 months prior to hysterectomy. None of the uteri contained dysplasia or cancer on histologic examination. 90.6% of smears reviewed had at least one cell or cell group with atypia mimicking dysplasia or cancer. These "litigation cells" were classified as follows: parabasal cells, metaplastic squamous cells, degenerated endocervical cells, reactive endocervical cells, endometrial cells, neutrophils, histiocytes, and air-dried cells. Diseases mimicked by these cells included squamous cell carcinoma, high-grade squamous intraepithelial lesion, low-grade squamous intraepithelial lesion, adenocarcinoma, and glandular dysplasia. These "litigation cells" can be correctly classified by experienced cytotechnologists and cytopathologists and recognized as benign. We recommend that in all cases of alleged malpractice against cytotechnologists and/or pathologists the smears should be reviewed by a panel of individuals trained and experienced in cytopathology. The smears should be reviewed without knowledge of the clinical outcome and in an environment that simulates the normal screening practice.