Growth of fetal rat liver cells in response to hydrocortisone

An immunoperoxidase technique was applied to the study of chromosomal structure. Using the immunoperoxidase technique with the anti-native DNA antibody, fibrous structure of human chromosomes and interchromosomal connections could be revealed by light microscopy in acid-alcohol fixed and air-dried chromosomal preparations.     

Sensitive detection of hybridocytochemical results by means of reflection-contrast microscopy

A new sensitive method for visualization of nonautoradiographic hybridization results in microscopic preparations is described. The method is based on the reflection of the incident light by diaminobenzidine precipitates deposited at the site of hybridization during an indirect hybridocytochemical procedure. The reflected light is detected by means of reflection-contrast microscopy. The applicability of the procedure is demonstrated with nucleic acid probes modified with 2-acetylaminofluorene groups. These in turn are localized in situ by an indirect immunoperoxidase reaction. Besides its sensitivity, this simple visualization technique possesses the additional advantages, over absorption and fluorescence microscopy, that it provides a total DNA counterstain and a chromosomal banding pattern.     

Choriocarcinoma metastatic to the lung. A cytologic study with identification of human choriogonadotropin with an immunoperoxidase technique

A case of choriocarcinoma metastatic to the lung following a previous hydatidiform mole is presented. It was possible to make definitive identification of trophoblastic elements on a needle aspiration biopsy using an immunoperoxidase staining technique, thus avoiding diagnostic thoracotomy prior to therapeutic intervention. A method of immunoperoxidase staining of previously fixed and Papanicolaou-stained needle aspiration biopsy specimens is also described, and other uses of the immunoperoxidase technique on needle biopsy specimens are discussed.     

Confirmation of genital herpes simplex viral infection by an immunoperoxidase technique

Over the 12-month period from April 1984 to April 1985, 512,000 gynecologic (Papanicolaou) smears were examined in the Provincial Screening Program in British Columbia. During this time, 307 patients were found to have smears that contained cells consistent with, or suggestive of, a herpes simplex viral (HSV) infection. The Papanicolaou-stained smears from these 307 cases were subsequently restained, without prior destaining, using an immunoperoxidase technique specific for type 2 HSV (HSV-2) and cross reactive with HSV-1. Of the 205 smears containing cells considered to be consistent with a herpes infection, 187 were positive using the immunoperoxidase technique. Of the 102 smears showing reactive cell changes though unlikely to be causes by an HSV infection, only 5 were positive using the immunoperoxidase technique. The results show that the immunoperoxidase technique is a rapid and reliable method of confirming a suspected diagnosis of herpetic infection and that it is particularly useful in those patients in whom the Papanicolaou smear findings are equivocal.     

The potential value of immunoperoxidase techniques in diagnostic cytology

A slightly modified immunoperoxidase method was developed in our laboratory and applied to a variety of aspiration and exfoliative cytologic material. Our aims were: (1) to explore the applicability of the immunoperoxidase procedure to diagnostic cytology, (2) to attempt to define the histogenesis of neoplastic cells when morphology alone proved insufficient, and (3) to investigate the possibility of differentiating reactive from neoplastic lymphoreticular disorders by studying their immunoglobulin patterns. Our findings indicate that the immunoperoxidase technique is applicable to cytologic material. The simplicity of the procedure, combined with its high sensitivity and excellent morphology, merits wider application of this technique to routine diagnostic cytology.     

Immunoperoxidase technique for identification of Mycoplasma gallisepticum and M. synoviae.

The direct immunoperoxidase technique was applied to the identification of Mycoplasma gallisepticum and M. synoviae by staining colonies on the agar plate. The results of this technique applied to 50 isolates of M. gallisepticum and M. synoviae correlated with those of the agar gel precipitation test to the same isolates. The immunoperoxidase technique was proved to be a specific and reliable method for the identification of M. gallisepticum and M. synoviae.     

The Actin-Related Protein BAF53 Is Essential for Chromosomal Subdomain Integrity

A chromosome territory is composed of chromosomal subdomains. The internal structure of chromosomal subdomains provides a structural framework for many genomic activities such as replication and DNA repair, and thus is key to determining the basis of their mechanisms. However, the internal structure and regulating proteins of a chromosomal subdomain remains elusive. Previously, we showed that the chromosome territory expanded after BAF53 knockdown. Because the integrity of chromosomal subdomains is a deciding factor of the volume of a chromosome territory, we examined here the effect of BAF53 knockdown on chromosomal subdomains. We found that BAF53 knockdown led to the disintegration of histone H2B-GFP-visualized chromosomal subdomains and BrdU-labeled replication foci. In addition, the size of DNA loops measured by the maximum fluorescent halo technique increased and became irregular after BAF53 knockdown, indicating DNA loops were released from the residual nuclear structure. These data can be accounted for by the model that BAF53 is prerequisite for maintaining the structural integrity of chromosomal subdomains.     

Cytologic demonstration of Entamoeba histolytica using immunoperoxidase techniques. Report of two cases

An indirect immunoperoxidase technique to detect Entamoeba histolytica in cell samples from patients suspected to have amebiasis is described. Using a rat antiserum specific for E. histolytica, the organism was clearly identified both in smears and in cell blocks. This immunoperoxidase technique seems to offer great possibilities for a specific, accurate and rapid identification of amebic infestation in diagnostic cytology.     

Rapid Typing of Herpes Simplex Virus Strains Using the Indirect Immunoperoxidase Method

The indirect immunoperoxidase technique with type-specific antisera was compared to kinetic neutralization for the typing of herpes simplex virus strains. There was complete agreement between the results obtained by kinetic neutralization and indirect immunoperoxidase. The indirect immunoperoxidase assay was far simpler to perform and interpret than the kinetic neutralization tests, and it offered a rapid means for the routine antigenic typing of herpes simplex isolates.     

Detection of Klinefelter syndrome by G-banding analysis combined with primed in situ labeling technique

Primed in situ labeling (PRINS) technique is an alternative to in situ hybridization for rapid chromosome screening. We employed triple-color PRINS technique to detect chromosomal abnormalities in Klinefelter syndrome patients diagnosed by G-banding karyotype analysis. Among 1034 infertile male patients, 134 were found to be cytogenetically abnormal, including 70 with chromosomal number abnormalities and 64 with chromosomal structure abnormalities. Among these cytogenetically abnormal patients, 56 were diagnosed as having Klinefelter syndrome. PRINS technique was used on cultured lymphocyte metaphase cells of the Klinefelter syndrome patients; the same result was obtained with G-banding karyotype analysis. PRINS proved to be a rapid and reliable method to detect numerical chromosome abnormalities in peripheral blood lymphocytes in metaphase.     

Cytodiagnosis of herpes simplex keratitis by means of an immunoperoxidase technique. A case report

Typical herpes simplex keratitis that developed in a 5-year-old boy was initially diagnosed cytologically in Papanicolaou-stained samples. Subsequently, an immunoperoxidase staining technique was used to identify the specific type of herpes simplex virus (HSV) in the destained cellular samples. The positive staining helped to establish the diagnosis of a type 1 HSV infection, permitting early treatment with acyclovir and subsequent complete recovery from the ocular herpetic infection. Emphasis is placed on the value of the immunoperoxidase technique for the rapid and specific diagnosis of cases of suspected HSV infection.     

The effects of different fixatives for immunofluorescent and immunoperoxidase localization of Factor VIII-related antigen in canine carotid artery and vascular prostheses

Summary The evaluation of vascular grafts seeded with autologous endothelial cells requires a reliable method of endothelial cell identification. Previous attempts to identify positively tissue Factor VIII-related antigen, found in relatively large amounts in vascular endothelial cells, proved to be inconsistent when immunoperoxidase and immunofluorescent staining techniques were tried. Because the Factor VIII antigen is very labile, this study was performed to determine an optimal fixation technique for demonstrating this antigen in frozen sections of endothelial tissue. Unfixed, acetone-fixed, and formalin-fixed sections of canine carotid artery as well as vascular grafts fixed in 1-ethyl-3-(3-diaminopropyl)-carbodiimide were examined by an indirect immunofluorescence technique. Also, the immunoperoxidase method of Factor VIII identification was applied to unfixed, acetone-fixed, and carbodiimide-fixed endothelial cell seeded vascular grafts. Acetone was the preferred fixative, resulting in excellent antigen preservation with minimal background staining. The immunoperoxidase technique of Factor VIII-related antigen identification was found to be the method of choice because of its sensitivity.     

Use of immunoperoxidase for the rapid identification of human myxoviruses and paramyxoviruses in tissue culture

The immunoperoxidase method, using commercially available antisera, was compared with standard virological methods for the identification and typing of 77 isolates of human myxoviruses and paramyxoviruses. Results of typing using neutralization tests and the immunoperoxidase technique were identical for 76 of the 77 isolates. With the immunoperoxidase method there was one false negative reaction, but no false positive reactions. Cross-reactivity between influenza A (soluble) and A₂/HK antisera with influenza A isolates was noted, but did not interfere with the interpretation of results. It is concluded that the immunoperoxidase method is ideally suited for the rapid identification and typing of common human respiratory viruses on a routine basis. It offers a number of decided advantages over both immunofluorescence and standard virological methods.     

The ontogeny of mullerian inhibiting substance in granulosa cells of the bovine ovarian follicle

Mullerian Inhibiting Substance (MIS) previously detected in the Sertoli cells of the calf testis has been localized in the granulosa cells of the ovarian Graafian follicle by using an immunoperoxidase technique and a monoclonal antibody (IG8) to MIS that almost completely blocks its biological activity. The immunoperoxidase technique (avidin-biotin complex method) demonstrated specific localization of MIS in the cytoplasm of the ovarian granulosa cells in the bovine Graafian follicles over a wide age span, i.e. one day, one week, three months, two-and-a-half years and five years. The presence of MIS in the ovary implies a function that is as yet unknown.     

Use of azide and hydrogen peroxide as an inhibitor for endogenous peroxidase in the immunoperoxidase method

We describe a simple and effective method for inhibition of endogenous peroxidase activity in the immunoperoxidase technique. Specimens are pre-treated with a mixture of azide and hydrogen peroxide, which is then followed by an indirect immunoperoxidase procedure. Comparison studies showed no significant loss of antigenicity or morphological details by this pre-treatment. The method is most useful for evaluating cell-specific antigens on specimens that have abundant endogenous peroxidase activity, such as blood and bone marrow.     

Use of immunocytochemical techniques for the localization of human placental lactogen.

The recent claim by Gau and Chard (Br J Obstet Gynaecol 83:876, 1976) that, on theoretical grounds, it may be impossible to demonstrate the presence of human placental lactogen in placental tissue using the immunoperoxidase technique, has been reinvestigated. Placental tissue fragments fixed in Carnoy's fluid retained their morphologic identity compared with tissue fixed in formalin. Using these nonformalin fixed tissues, human placental lactogen was successfully localized within the cytoplasm of the syncytial layer of the placental villus. It is concluded that placental villi at term do in fact contain sufficient human placental lactogen to be demonstrated using the immunoperoxidase technique in contrast to the observation of Gau and Chard.     

On the quantitation of SV40 virus by plaque assay and immunoperoxidase technique.

Procedures are described for the quantitation of SV40 virus infectivity by plaque formation within 7 days and T antigen assay by the sensitive and economical indirect immunoperoxidase technique.     

Influence of two different fixatives on the identification of plasma cells in human rectal mucosa

Plasma cells in sections of bisected human rectal biopsy specimens, fixed in two alternative fixatives, were enumerated after staining by an indirect immunoperoxidase procedure intended to demonstrate immunoglobulin-containing cells. The counts of immunoperoxidase-positive plasma cells were significantly higher after fixation in formol sublimate than after fixation in formol saline. Formol sublimate appears to be a more reliable fixative than formol saline for specimens of rectal mucosa in which quantitation of plasma cells, stained for intracellular immunoglobulin by an immunoperoxidase technique, is intended.