Harold N. Carlisle

Properdin Levels in Splenectomized Persons.

Summary Properdin titers were definitely lower in 105 splenectomized persons than in 113 normal; healthy subjects. Within the splenectomized group, there was no correlation between properdin level and age of individual, age at splenectomy, and years post-splenectomy. Properdin titers were significantly lower in splenectomized females, but the sex difference was minimal in comparison to the difference between total splenectomized and control groups. Suggestive evidence is presented that low properdin levels in splenectomized persons are related in part to absence of spleen.

Antibody response in hematologic patients.

Summary A single injection of 0.5 ml of phenolized tularemia vaccine elicited detectable agglutinating antibodies in 67 of 162(41.4%) patients with hematologic disorders as compared to 45 of 48(93.7%) in normal controls. Particularly significant was the lack of response in 23 of 25 chronic lymphatic leukemia and in 37 of 57 lymphoma patients. In the latter group only 5 of 27 females as compared to 15 of 30 males exhibited antibodies.

Comparison of Tobramycin, Gentamicin, Colistin, and Carbenicillin in Pseudomonas Sepsis in Monkeys

Intravenous inoculation of 3.4 × 1010 to 7.4 × 1010Pseudomonas aeruginosa organisms into rhesus monkeys 4 days after intravenous or intratracheal inoculation of 2.0 to 2.5 mg of vincristine sulfate resulted in fatal sepsis in eight of nine monkeys. After intramuscular administration, in two equal doses, of 5 mg of tobramycin, gentamicin, and colistin per kg per day beginning 16 hr after challenge, 4 of 11, 4 of 11, and 3 of 10 monkeys died, respectively. Administration of daily doses of 100 to 400 mg of carbenicillin per kg was followed by death in 5 of 12. Duration of illness in the surviving monkeys in each therapy group was similar. Under the conditions of this study, prior administration of vincristine sulfate resulted in a decrease in leukocytes and enhanced susceptibility to Pseudomonas infection. Using this model for studies of comparative efficacy of antibiotics, we observed comparable results after treatment with tobramycin, gentamicin, colistin, and carbenicillin.

AEROSOL EXPOSURE OF MONKEYS TO INFLUENZA VIRUS.

Discussion and summary Previous studies from this laboratory(1) showed that intratracheal inoculation of rhesus monkeys with the PR8 strain of influenza virus resulted in mild illness in 2 of 4 monkeys; after intranasal inoculation, no clinical signs of illness were observed. Results of studies by others (2–5) have varied with the influenza virus strain and monkey species employed. In all, virus was administered intratracheally or intranasally, and in general, clinical evidence of disease was minimal or absent. The development of quantitative procedures for exposure of experimental animals to aerosols of infective organisms(6) suggested reinvestigation of the response of monkeys following challenge with influenza virus by these methods. The present report describes the clinical, hematologic and serologic response of rhesus and cynomolgus monkeys after aerosol exposure to the PR8 strain of influenza virus. Materials and methods. Challenge of young adult monkeys, Macaca mulatta and M. irus, was conducted in a Model 3 Henderson apparatus(6) by previously described methods (7,8). The aerosol generator was charged with mouse lung nitrate containing about 1.0 × 108 mouse intranasal LD50 per ml of the PR8 strain of influenza A virus. Monkey doses were calculated from studies of concurrently exposed 14–16 g white mice. Intratracheal inoculation of allantoic fluids(9) containing strains A/PR8/34, Swine/1976/31, A2/Japan/305/57, and B/Great Lakes/1739/54 was performed as described previously(1). Physical examinations, hematologic and serologic studies were carried out for 2 weeks prior to challenge. After challenge, monkeys were examined twice daily. Femoral vein blood was used for blood counts and C-reactive protein (CRP) tests daily or every other day, and weekly for serologic studies.

Histoplasmin-latex agglutination test. II. Results with human sera.

Summary This laboratory has now had 10 years experience with the collodion agglutination test for histoplasmosis (3-9). We use it routinely in screening for active histoplasmosis. The test itself is simple to perform and read. However, smaller laboratories or institutions with lesser demand for serologic studies for histoplasmosis find the preparation of collodion particles too time-consuming for their purposes. Commercially-prepared latex particles show similar results as collodion particles when both are sensitized with histoplasmin. It is suggested from these studies that, as in the collodion agglutination test, a 4 + reaction at 1:5 dilution or higher is compatible with active histoplasmosis. In 4 instances 3 + latex agglutinations were observed in sera showing 4+ collodion tests. Thus, at the present time, 3+ agglutinations with latex are placed in the “suspicious” category. As with collodion agglutinations, 1-2 + reactions are considered negative. Studies are in progress to evaluate further the use of histoplasmin-latex agglutinations in serologic diagnosis of histoplasmosis.

Comparison of Gentamicin, Carbenicillin and Gentamicin, and Carbenicillin in Pseudomonas Sepsis in Monkeys

Intravenous inoculation of 6.0 × 1010Pseudomonas aeruginosa organisms into rhesus monkeys 4 days after intratracheal inoculation of 2.5 mg of vincristine sulfate resulted in fatal sepsis in all of three untreated control monkeys. After intramuscular administration of either 2.5 mg of gentamicin or 50 mg of carbenicillin per kg per day, three of four monkeys in each group survived. When both antibiotics were given at the same dose but in separate sites, six of eight monkeys survived. Antibacterial activity of serum from infected monkeys or normal monkeys was not appreciably different when the two antibiotics were combined. Under the conditions of this study, there was no apparent difference in response of monkeys treated either with gentamicin or carbenicillin alone or with the combination of the two antibiotics.

Histoplasmosis: to skin test or not to skin test?

SummaryA single skin test with commercially-available histoplasmin did not stimulate significant antibody response in the sera of 187 persons when measured by the yeast phase complement-fixation, collodion agglutination or histoplasmin latex agglutination tests. Similarly, no effect was noted with the histoplasmin complement-fixation test in the sera of 97 skin-test negative individuals; in contrast 26.7% of skin-test positive persons developed significant titer increases.

ANTIBODY RESPONSE IN SPLENECTOMIZED MONKEYS.

Summary Splenectomized monkeys showed antibody responses similar to normal monkeys after subcutaneous inoculation with tularemia and typhoid vaccines and after intravenous typhoid vaccine. Impaired antibody response followed a single intravenous inoculation of sheep erythrocytes as well as after a single booster, but not after 3 daily intravenous injections.

STREPTOCOCCAL INFECTION IN NORMAL AND SPLENECTOMIZED MONKEYS.

Summary No significant differences in susceptibility were noted between normal and splenectomized monkeys following aerosol or intravenous challenge with a Group A hemolytic streptococcus. No mortalities were observed after aerosol challenge. Intravenous challenge induced obvious disease with mortality in 6 of 11 splenectomized and 5 of 10 normal monkeys. Laboratory findings were essentially similar including C-reactive protein and antistreptolysin response.

Experimental Histoplasmosis in Monkeys.

Summary Severe disease was produced in monkeys by yeast phase H. capsulatum administered intravenously and intratracheally. Monkeys inoculated intranasally exhibited a more mild disease process. No significant clinical signs of illness were seen in monkeys inoculated by the gastric route.