Lorraine Friedman

Passive immunization of mice against Candida albicans

Three similar groups of mice were given either pooled immune serum from vaccinated mice, normal mouse serum or normal saline. The animals were then challenged simultaneously with a single intravenous dose of 1 × 105 viable units of C. albicans.Passive immunization conferred demonstrable protection, inasmuch as the length of survival of those animals that died was considerably extended, and 33% of the animals survived the entire period of observation.

A new species of Microsporum pathogenic to man and animals

A new dermatophyte species, Microsporum vanbreuseghemii, is described. This fungus was isolated from ringworm of a Malabar squirrel, a dog, and 2 human beings. The fungus is characterized by the development of many large, thick-walled, echinulate, cylindro-fusiform macroconidia. Cleistothecia with ascospores were produced by all strains when grown on hair on the surface of soil. It is proposed that the perfect form of M. vanbreuseghemii be included in the genus Nannizzia as N. grubyia sp. nov.

Active Immunization of Mice against Candida albicans.

Summary Mice were vaccinated by repeated subcutaneous inoculations of living, merthiolate-killed, or sonically-ruptured cells of C. albicans and were then challenged intravenously with 104 or 105 viable particles of a homologous strain. Although not all of the vaccinated mice survived challenge, a significant degree of resistance was conferred since fewer deaths occurred among vaccinated animals.

Studies on the genus Basidiobolus with reclassification of the species pathogenic for man

The etiologic agent of human subcutaneous phycomycosis was found to be a species of Basidiobolus which is characterized by the lack of a distinctive odor, by being able to grow well at human body temperature and in having smooth-walled zygospores. These features separate it from the saprophyte, B. ranarum, which has a distinctive odor, does not grow well at 37°C. and has rough-walled zygospores. It is separated from B. haptosporus on the basis that this saprophyte is not well-adapted for growth at human body temperature. B. magnus and B. microsporus possess other distinctly differing morphological features. The pattern is considered by the authors to be of the same species as B. meristosporus, a thermotolerant fungus which does not differ significantly in morphology from the human pathogen.

Mechanisms of Native and Acquired Resistance to Infection with Cryptococcus Neoformans

AbstractThe mechanisms of resistance mustered by the host to ward off infection with Cryptococcus neoformans mirror many of the classical responses shown with intracellular bacteria. Thus, the administration of an appropriate cellular antigen can protect animals from an otherwise lethal infection in the absence of demonstrable humoral antibody. It is now known that this resistance most probably can be transferred both by “immune” lymphocytes and macrophages.36 A similar effect can be obtained with endotoxin, but limitation of the infection in this case apparently requires the presence of circulating antibody directed against the capsule. Neutralization of the adverse effects of extracellular polysaccharide on chemotaxis and pinocytosis is the most plausible explanation.In spite of the formidable natural protection afforded by the respiratory apparatus, the ultimate mediators in defense against C. neoformans must be the phagocytes, most particularly the macrophages. Although the metabolic activity of fully...

THE QUESTION OF IMMUNITY IN RINGWORM INFECTIONS

There is some indication that an immune response against dermatophytes is developed in experimental animals in view of the early work of Delamater’ and Delamater and Benham2 with Trichophylon menfagrophytes and of the more recent work of Reiss and Leonard3 with Microsporum canis and of Keeney and Huppert4 with T . menfagrophyfes. Also, Huppert and Keeney5 felt that they had demonstrated an acquired resistance against dermatophyte infections in human volunteers previously immunized with antigens of T. menlagrophytes. For the most part, however, the immunity developed has been partial in that the course of the disease following immunization was only shorter and milder than that normally observed. The role of such an altered response under natural conditions is nebulous, in part because of so-called “natural resistance” to dermatophyte infections that has been described by many, particularly well by Barlow.G I t is generally assumed that most persons are exposed to dermatophyte infections, yet relatively few develop clinical disease. This is well exemplified by the study of Kligman? who found that only 5 per cent of a group of institutionalized children had acquired a natural infection during an epidemic of tinea capitis caused by Microsforon audouini, despite the intimate and prolonged contact this situation provided. The factors that limit the spread of such epidemics would seem to be more complex than merely the natural resistance of certain individuals and might well be strongly influenced by other factors such as infectivity and virulence of the strain, size of the inoculum received by the individual, and the effect of local trauma, as well as the possibility of altered response following infection. For example, it is our impression, based more on speculation than data, that M . audouini, although perhaps more virulent than other of the causative agents of tinea capitis, may not be a5 infectious. I t was our desire to determine the presence, or absence, of immunity under natural conditions following recovery from naturally acquired tinea capitis. The observation that children usually do not have second bouts with this disease would seem a t first glance sufficient evidence for a concept of acquired immunity. However, since the opportunity for first infections often is not great, the failure to acquire a second infection might well be attributable to lack of opportunity rather than immunity. Of 718 children treated for tinea capitis in the Tulane University clinic during a threeyear period, not one returned with a second infection, despite entirely free medical care, including medication. At the time griseofulvin first became available, a deliberate effort was made to set up studies to explore the possibility of immunity following infection. I t seemed to us that treating one sibling and then leaving that child exposed to one or more untreated children would provide a long-awaited opportunity. * The work described in this paper was supported in part by Grant F, 1224 from the National Institute of Allergy and Infectious Diseases, Public Health Service, Bethesda, Md.

Antigenic relationships between the fungus causing subcutaneous phycomycosis and saprophytic isolates of Basidiobolus meristosporus and B. ranarum.

The antigenic relationships between strains of Basidiobolus isolated from human disease and saprophytic isolates of B. meristosporus and B. ranarum were investigated using reciprocal hemagglutination inhibition and hemagglutinin absorption techniques. The results showed that saprophytic isolates of B. meristosporus are antigenically similar to the pathogen in that the hemagglutinating activity of B. meristosporus antisera could be removed by substances derived from the human pathogenic isolates. In contrast, B. ranarum and the pathogen had distinct antigenic differences as shown by the inability of material from any of the pathogenic isolates to inhibit the homologous antigen-antibody reactions of the saprophyte, B. ranarum. It is concluded that the fungus thus far isolated from human subcutaneous phycomycosis should be identified as B. meristosporus.

Falsely Positive Pyrogenic Responses Induced in Rabbits by Latex Particles.

Summary An endotoxin-like febrile response was elicited in rabbits by intravenous inoculation of washed polystyrene latex particles. Alkaline treatment of the latex particles reduced but did not eliminate the pyrogenic activity, whereas particles treated with acid were incapable of inducing a febrile response. Exposure of the non-pyrogenic, acid-treated particles to a suspension of Escherichia coli endotoxin of the phenol-water type restored pyrogenicity to the particles. Exhaustive washing of these endo-toxin-treated particles with non-pyrogenic saline did not remove the fever producing substances.