We investigated the antigenic maturation of rabies virus N protein, for which we used some conformational epitope-specific monoclonal antibodies (MAbs) and an MAb (5-2-26) against a phosphorylation-dependent linear epitope. Infected cells were lysed with a deoxycholate-free lysis buffer and separated by ultracentrifugation into the soluble top and the nucleocapsid fractions. None of the study MAbs recognized N proteins in the top fraction, whereas nucleocapsid-associated N proteins were recognized by all of the MAbs. Immunoprecipitation with polyclonal anti-N antibodies coprecipitated the P proteins from the top fraction, indicating that soluble N proteins are mostly associated with the P protein. The N proteins dissociated from both the N-P complex and nucleocapsids were recognized by none of the study MAbs, whereas the MAb 5-2-6 recognized the SDS-denatured N proteins of the nucleocapsid but not of the top fraction. In addition, the phosphorylation-deficient mutant N proteins were shown to be similarly accumulated as the wild-type N proteins into the viral inclusion bodies, defined as the virus-specific structures composed of viral nucleocapsids, that are produced in the cytoplasm of the infected cells. Based on these results, we believe that newly synthesized N proteins are not immediately phosphorylated at serine-389 (a common phosphorylation site) but are first associated with the P protein. After being used for encapsidation of the viral RNA, the N proteins undergo conformational changes, whereby epitopes for the conformation-specific MAbs are formed and become phosphorylated at serine-389.

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Although fine-needle aspiration cytology is a routine procedure for the diagnosis of breast carcinoma, cytologic specimens have rarely been used for evaluation of hormone receptor status and HER2/neu overexpression. In order to compare the biological markers on cytology and on histology, routinely fixed smears of 110 primary breast carcinomas were immunostained for estrogen receptor (ER), progesterone receptor (PgR), and HER2/neu by automated immunostainer and the results were compared with the corresponding histologic sections. ER was expressed in 76 of 110 (69%) cases and PgR was expressed in 51 of 110 (46%). Overexpression of HER2/neu was observed in 30 of 110 (27%) cases. Concordance between cytology and histology was 98% for ER, 95% for PgR, and 100% for HER2/neu. There was no false positive result on smears. Diagnostic pitfalls in determination of hormone receptor status on smears included intratumoral heterogeneity and presence of mucin.

An effective vaccine against sexual transmission of human immunodeficiency virus (HIV) should elicit both systemic and mucosal immune responses. In this study, to examine the possibility of using an attenuated virus for mucosal immunization, four female macaques were intranasally or intravenously administered with a chimeric simian-human immunodeficiency virus with a deleted nef gene (SHIV-dn). Although all the monkeys had anti-HIV-1 antibodies with neutralizing activity in the plasma, the intranasally immunized monkeys had much higher levels of HIV-1 Env-specific IgG and IgA antibodies in mucosal secretions compared with the intravenously immunized monkeys. Moreover, three of four intranasally immunized monkeys were completely protected from intravaginal challenge with a pathogenic virus, SHIV-89.6P, whereas only one intravenously immunized monkey was protected. Thus, intranasal immunization of an attenuated virus can induce the protective efficacy against intravaginal infection.