Frances G. Felton

A Hospital Outbreak of Serratia marcescens Associated with Ultrasonic Nebulizers

Abstract A sevenfold increase in the frequency of isolation ofSerratia marcescenswas noted during a 2-month period. Nineteen patients were involved, and the majority of these patients acquired the ...

Enzyme-linked immunosorbent assays in murine cryptococcosis

In this investigation, enzyme-linked immunosorbent assay (ElISA) procedures were used to study the time of appearance and the duration of demonstrable antigen and antibody in body fluids of mice with disseminated cryptococcosis. The ELISA antigen procedure detected cryptococcal capsular polysaccharide (CCP) in the serum and urine of infected mice 3 days after infection--4 days before it could be demonstrated by the latex agglutination procedure. ELISA-reactive antibody was present throughout the course of infection (mean death time, 32 days), whereas antibody was not detected by whole cell agglutination after day 20. High serum concentrations of CCP (titers to 64,000) persisted throughout the course of infection, while antibody declined to low levels with progression of disease. ELISA provides a sensitive system for quantitation and monitoring of antigen (CCP) processing and clearance (or storage), and for cryptococcal antibody formation in progressive cryptococcosis.

Delayed hypersensitivity to cryptococcin in man

Twenty-six of 82 healthy persons from a small community in Oklahoma responded to intradermal testing with cryptococcin by development of typical delayed skin reactions with induration of 5 mm. or greater in diameter. Although the hyper-reactivity to cryptococcin may be due to past exposure to C. neoformans, exact interpretation of the observed reactions cannot be definite at this time because of concomitant presence of histoplasmin sensitivity in some of the subjects tested.

Cell wall differences of patient and soil isolates of Cryptococcus neoformans

Two isolates of Cryptococcus neoformans were studied to determine whether or not differences in chemical composition of the cell walls existed. Aerated cultures of both isolates were grown at 37°C. in a synthetic liquid medium. A purified cell wall fraction was obtained by repeated passage of cells through a French pressure cell followed by differential centrifugation. Chemical analyses of cell wall fractions of each of these strains showed quantitative differences in 3 major groups of compounds. The isolate from the patient contained a higher percentage of hexose and a lower percentage of hexosamines and lipids than did the soil isolate.