Keratoacanthomas are variously regarded as a self-limiting variant of squamous cell carcinoma or as a distinct benign lesion and they very seldom show attributes normally associated with malignant behaviour, such as perineural invasion. Herein we report the case of a keratoacanthoma with venous invasion proven by immunoperoxidase and elastic tissue stains.

Of 33 rabbits inoculated with Lyme disease spirochetes, two developed erythema chronicum migrans at the site of inoculation. Spirochetes were seen in skin biopsies of one of the lesions with immunoperoxidase and Warthin-Starry stains. Spirochetes were also recovered from the blood of two additional rabbits two weeks post-inoculation. These findings are characteristic of early Lyme disease in hu...

An immunoperoxidase technique was used to demonstrate carcinoembryonic antigen (CEA) in sections of proctocolectomy specimens from nine cases of ulcerative colitis in some of which carcinoma and premalignant change had developed. Carcinoma and premalignant change stained positively for CEA in contrast with benign mucosa, whether or not inflammatory dysplasia was present.

A 38-year-old black man died from acquired immunodeficiency syndrome (AIDS) after a 15-month course. The autopsy revealed a pancolitis and a pneumonia caused by cytomegalovirus (CMV). Exceptionally, there also was a periventricular encephalitis caused by the same organism. Identification of the virus was aided by immunoperoxidase methods.

A murine monoclonal antibody, which recognises various serotypes of group B Streptococcus in formalin fixed, paraffin embedded tissue, was used to show the organism in necropsy specimens of newborn infant lung by an indirect immunoperoxidase technique. The method seemed to be complementary to that of Gram staining, and may be successfully used to identify group B Streptococcus antigen in histop...

The structure of regions with a high concentration of ACh receptors (clusters) on cultured skeletal muscle myotubes was examined by immunoperoxidase staining of bound alphaBT. The clusters did not appear to differ from the other regions except in their higher concentration of receptor.

This is a case report of a renal carcinoma which was secreting inactive renin. Using an antibody to human renin and the indirect immunoperoxidase technique, the renin-containing cells were localised within the tumour. These were found to be small granular cells situated in a perivascular position. The histological immunocytochemical and ultrastructural features of these cells are described.

Results The three slides of the serial sectioned material-peroxidase uncounterstained, Perls' Prussian blue, and the peroxidase counterstained with Perls' Prus-sian blue-were carefully compared by matching the architecture of the fields using a comparison bridge. Neither the prolactin nor the haemosiderin components seemed to be diminished as a result of the extra staining procedure. Low backgr...

Sera of C3H/Z/Dm mice bearing spontaneous mam mary tumors, sera of apparently normal C3H/Z/Dm mice at different ages, and a serum of an A/Dm mouse with spontaneous breast cancer were tested by the indirect immunoperoxidase method against cells of C3H/HeJ spon taneous mammary tumor line constantly producing type B or mouse mammary tumor virus particles. The sera were also tested against cells of...

An indirect immunoperoxidase technique has been used to identify enteropathogens in formol-sublimate fixed paraffin embedded sections of calf intestine. Infections with bovine rotavirus, bovine coronavirus, Newbury agent SRV -1, and K99+ Escherichia coli have been detected in the intestines from experimentally infected and conventially reared diarrhoeic or normal calves. The ability to visualiz...