Chromosome alterations in renal cell carcinoma of childhood may correspond to aberrations in adults

Some cytologic specimens may be limited in quantity, and this may hamper or preclude the performance of immunocytochemistry (ICC) in cases where more than one antibody (ab) is required by ICC to arrive at a definitive diagnosis. There is very little information in the cytology literature regarding the use of ICC for specimens that are limited in quantity. In this study, we describe a method, derived from the principles of double immunolabelling, whereby more than one ab test can be repeatedly used on the same Papanicolaou stained slide. Multiple cytologic scrape preparations fixed in 95% ethanol were obtained from fresh surgical specimens including carcinomas of the breast, endometrium, stomach, ovary and colon. Nonneoplastic tissues included tonsil (2), lymph node (2) and myometrium. Papanicolaou stained slides or unstained slides were subjected to two sequential ICC procedures, the first in which the ab was known to be nonreactive with the cells (insulin, glucagon, or somatostatin) and the second in which the ab was known to be positive in the cells. Positive controls for the known positive abs included a single-step ICC procedure as well as the tissue section. The test abs included CAM 5.2, AE1/3, K903, LCA, L26, UCHL-1, s-100, mCEA, GCDFP-15, vimentin, muscle specific actin and desmin. Identical two-step ab procedures were carried out on the tissues from the same surgical specimens. For Papanicolaou stained cytologic specimens, abs were reactive and gave excellent results for the repeat second-step ICC method. There was no false positive or false negative staining. This "repeat ICC" method also gave excellent results on the tissue sections. Immunocytochemistry can be performed more than once on the very same cytologic specimen if the initial ICC antibody attempt is negative. This method may be especially useful in situations where more than one antibody is needed on a very limited cytologic sample size.     

Vaccine genotype and route of administration affect pseudorabies field virus latency load after challenge

The influence of vaccine genotype and route of administration on the efficacy of pseudorabies virus (PRV) vaccines against virulent PRV challenge was evaluated in a controlled experiment using five genotypically distinct modified live vaccines (MLVs) for PRV. Several of these MLVs share deletions in specific genes, however, each has its deletion in a different locus within that gene. Pigs were vaccinated with each vaccine, either via the intramuscular or intranasal route, and subsequently challenged with a highly virulent PRV field strain. During a 2-week period following challenge with virulent PRV, each of the vaccine strains used in this study was evaluated for its effectiveness in the reduction of clinical signs, prevention of growth retardation and virulent virus shedding. One month after challenge, tissues were collected and analyzed for virulent PRV latency load by a recently developed method for the electrochemiluminescent quantitation of latent herpesvirus DNA in animal tissues after PCR amplification. It was determined that all vaccination protocols provided protection against clinical signs resulting from field virus challenge and reduced both field virus shedding and latency load after field virus challenge. Our results indicated that vaccine efficacy was significantly influenced by the modified live vaccine strain and route of administration. Compared to unvaccinated pigs, vaccination reduced field virus latency load in trigeminal ganglia, but significant differences were found between vaccines and routes of administration. We conclude that vaccine genotype plays a role in the effectiveness of PRV MLVs.     

Use of primary cell cultures and intact isolated glandular epithelia for X-ray microanalysis

Changes in the elemental composition of cells during isolation of glandular epithelia were studied by electron probe X-ray microanalysis. Fine chopping of rat submandibular gland followed by enzymatic treatment for 15 min caused marked increases in Na and Cl and a decrease in K concentrations in acinar cells. After enzymatic treatment for 50 min, Na, Cl and K concentrations returned to close to the control level. Mechanical disaggregation of the acinar clumps following enzymatic treatment resulted again in minor increases in Na and Cl and a marked decrease in K concentration. Exposure of isolated acini to cholinergic stimulation in vitro resulted in secretion of Cl and K from the acinar cells. Dissection of the sweat gland from human skin caused a decrease in the K/Na ratio. Incubation of the gland for 30–45 min with collagenase gave rise to a gradual decrease in the K/Na ratio. After mechanical separation of the gland into the secretory coil and reabsorptive duct, a further reduction of the K/Na ratio was seen. However, the duct cells had a much lower K/Na ratio and higher Ca concentration than the coil cells. In primary cultures, the K/Na ratios of the coil and duct cells returned to the in situ level. The elemental composition of sweat gland cells incubated in collagenase-containing medium was no different from that in cells incubated in collagenase-free medium. In the intact collagenase-isolated tissue, Cl^? secretion in the coil was elicited by carbachol but not by cAMP, whereas in the duct cells the reverse was the case. In primary cell cultures, Cl^? efflux in both coil and duct cells could be elicited by both carbachol and cAMP. In conclusion, although changes in elemental composition of gland cells during the isolation procedure occur, physiological responses can be detected. When primary cell cultures are used, it should be borne in mind that cultured cells may have physiological properties different from those of the intact tissue.