Clinicopathological report Periocular tumour of the follicular infundibulum.

Tumour of the follicular infundibulum (TFI) is an uncommon, benign lesion of the skin adnexae. Four cases are reported of periocular TFI. In all cases a clinical diagnosis of basal cell carcinoma was made before surgery; however, histopatholog ca examination revealed TFI. This is an epithelial tumour showing differentiation along the lines of the follicular infundibulum. Characteristic features are a shelf-like proliferat on of pale epithelia cells in the upper dermis, attachment to the epidermis and the upper portions of the pilosebaceous units, a dense border of elastic fibres, and palisading of the peripheral cell layer of the tumour plate. This benign tumour has not, to the authors' knowledge, been reported in the ophthalmic literature. It has a non-specific appearance and may be clinically misdiagnosed as naevus sebaceous, xanthoma, seborrhoeic keratosis, or basal cell carcinoma.

In vitro antibody-enzyme conjugates with specific bactericidal activity.

IgG with antibacterial antibody opsonic activity was isolated from rabbit antisera produced by intravenous hyperimmunization with several test strains of pneumococci, Group A beta-hemolytic streptococci, Staphylococcus aureus, Proteus mirabilis, Pseudomonas aeruginosa, and Escherichia coli. Antibody-enzyme conjugates were prepared, using diethylmalonimidate to couple glucose oxidase to IgG antibacterial antibody preparations. Opsonic human IgG obtained from serum of patients with subacute bacterial endocarditis was also conjugated to glucose oxidase. Antibody-enzyme conjugates retained combining specificity for test bacteria as demonstrated by indirect immunofluorescence. In vitro test for bactericidal activity of antibody-enzyme conjugates utilized potassium iodide, lactoperoxidase, and glucose as cofactors. Under these conditions glucose oxidase conjugated to antibody generates hydrogen peroxide, and lactoperoxidase enzyme catalyzes the reduction of hydrogen peroxide with simultaneous oxidation of I(-) and halogenation and killing of test bacteria. Potent in vitro bactericidal activity of this system was repeatedly demonstrated for antibody-enzyme conjugates against pneumococci, streptococci, S. aureus, P. mirabilis, and E. coli. However, no bactericidal effect was demonstrable with antibody-enzyme conjugates and two test strains of P. aeruginosa. Bactericidal activity of antibody-enzyme conjugates appeared to parallel original opsonic potency of unconjugated IgG preparations. Antibody-enzyme conjugates at concentrations as low as 0.01 mg/ml were capable of intense bactericidal activity producing substantial drops in surviving bacterial counts within 30-60 min after initiation of assay. These in vitro bactericidal systems indicate that the concept of antibacterial antibody-enzyme conjugates may possibly be adaptable as a mechanism for treatment of patients with leukocyte dysfunction or fulminant bacteremia.