We report the first ubiquitous green fluorescent protein expression in chicks using a lentiviral vector approach, with eGFP under the control of the phosphoglycerol kinase promoter. Several demonstrations of germline transmission in chicks have been reported previously, using markers that produce tissue-specific, but not ubiquitous, expression. Using embryos sired by a heterozygous male, we demonstrate germline transmission in the embryonic tissue that expresses eGFP uniformly, and that can be used in tissue transplants and processed by in situ hybridization and immunocytochemistry. Transgenic tissue is identifiable by both fluorescence microscopy and immunolabeling, resulting in a permanent marker identifying transgenic cells following processing of the tissue. Stable integration of the transgene has allowed breeding of homozygous males and females that will be used to produce transgenic embryos in 100% of eggs laid upon reaching sexual maturity. These results demonstrate that a transgenic approach in the chick model system is viable and useful even though a relatively long generation time is required. The transgenic chick model will benefit studies on embryonic development, as well as providing the pharmaceutical industry with an economical bioreactor.

Hepatic ethanol metabolism generates the reactive intermediate, acetaldehyde, whichbinds to proteins. The binding of acetaldehyde to purified enzymes was determined in order to ascertain whether such binding altered their catalytic functions. [¹⁴C]Acetaldehyde was incubated with alcohol dehydrogenase, glucose–6–phosphate dehydrogenase, lactate dehydrogenase and RNase A, each at 37°C(pH 7.4). In some reactions, sodium cyanoborohydride was included for stabilization of Schiff bases, formed as a result of the reaction between acetaldehyde and the amino groups of the enzymes. Portions of each reaction mixture were removed for determination ofstable and total (stable plus borohydride–reducible) adducts. Alcohol dehydrogenase and lactate dehydrogenase were not inhibited by adduct formation. Glucose–6–phosphate dehydrogenase and RNase, the activities of which depend on a lysine residue at their catalytic sites, were inhibited in a dose– and time–dependent manner. The degree of inhibition directly correlated with total adduct formation. Phosphate, known to inhibit binding to the active site lysine of RNase, prevented the inhibition of catalytic activity caused by adduct formation. These findings indicate thatthe binding of acetaldehyde to lysine at the catalytic site can inhibit enzyme activity.

Multi-color whole-mount in situ hybridization is a powerful technique for comparing the spatial expression patterns of two or more genes in developing embryos. We have developed an amplified triple-label whole-mount fluorescence in situ hybridization (FISH) protocol that permits detection of three different mRNAs in a single embryo. Our protocol uses simultaneous in situ hybridization to haptenylated riboprobes, followed by sequential antibody detection using anti-hapten antibodies conjugated to horseradish peroxidase, and the tyramide signal amplification (TSA) fluorescence detection system. Conventional fluorescence microscopy identifies areas of overlapping gene expression at the tissue level, whereas confocal fluorescence microscopy permits single-cell resolution and differentiates specialized cell types within a given tissue. This protocol will provide researchers engaged in the use of FISH with a solid starting point for adapting their own in situ hybridization protocols, either alone or in combination with immunohistochemistry or green fluorescence protein colocalization. Developmental Dynamics 229:651–657, 2004.

Objective. Influenza B virus causes epidemic infection in normal children, but only one case of infection in an immunocompromised solid organ transplant (SOT) recipient has been reported. Characterization of the clinical course of influenza B virus infection in pediatric SOT recipients may increase the utilization of preventive and therapeutic interventions by pediatricians caring for these immunocompromised children. Design. Retrospective chart review of patients whose respiratory viral cultures yielded influenza B from January 1989 through March 1992. Patients. Twelve pediatric SOT recipients with influenza B virus infection were identified. These included five renal, four hepatic, and three cardiac allograft recipients, ranging from 19 months to 17 years 9 months of age (median 6 years 2 months). The post-transplant interval ranged from 6 weeks to 4 years 6 months (average 26.7 months). No patient had been immunized against influenza. Exposure histories were documented for eight children; five of these occurred in the hospital. Results. Clinical symptoms included fever (12/12), respiratory (11/12), or gastrointestinal complaints (8/12). Five patients had neurologic involvement; one died of uncal herniation. Ten children were hospitalized (median duration, 3 days; range, 2 to 79 days). Two patients (post-transplant interval, 3 to 8 months) required mechanical ventilation, and one of these received aerosolized ribavirin. Three children had concurrent allograft rejection. Conclusions. Influenza B infection is potentially life-threatening in pediatric SOT recipients. We recommend annual immunization of pediatric SOT recipients, their household contacts, and health care workers. Prospective studies are needed to evaluate the efficacy of influenza vaccination in pediatric SOT recipients.