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Biomedical subjects

F Espersen

Publications and source records attributed to F Espersen.

At least 163 records · Page 9Linked to original sources
PubMed1984

Tumor growth inhibition by protein A and non-protein A containing Staphylococcus aureus in a mouse mammary carcinoma model.

Reinfusion of tumor-bearer plasma after absorption with killed Staphylococcus aureus strain Cowan I may be followed by inhibition or even acute necrosis of animal and human tumors. The effect has been attributed to protein A produced in large amounts by this staphylococcus. We have examined the effect upon the growth of a transplanted GR mouse mammary tumor of intraperitoneal inoculation of three strains of S. aureus characterized by being either protein A-rich or protein A-free. A significant tumor growth inhibition was found with all three strains of S. aureus. Serum levels of IgG1, IgG2 and IgM were found to be substantially increased. Crossed immunoelectrophoresis revealed increased numbers and titres of precipitins against staphylococcal antigens. It is concluded that staphylococcal moieties other than protein A may be involved in the tumor growth inhibition. The possibility and role of complement activation by protein A-like molecules through the alternative F(ab)2 reactivity is discussed.

Adenocarcinoma↗
PubMed1984

Human serum and plasma increase mouse mortality in Staphylococcus aureus intraperitoneal infection.

The influence of human plasma, serum, purified fibrinogen, and fibronectin on Staphylococcus aureus intraperitoneal infection in non-immune mice was studied. Mouse mortality was used as a measure of staphylococcal virulence. Both human plasma and serum were shown to enhance the virulence of S.aureus strain E 2371 and strain E 2476 when added to the bacteria before challenge. This effect of serum was unaffected by storage for 24 h at 37 degrees C or complement-inactivation for 1 h at 56 degrees C. Purified fibrinogen and fibronectin did not influence the S. aureus virulence. It is suggested that the effects of plasma and serum described here might play a role in the establishment of S.aureus infections in humans.

Animals↗
PubMed1984

Effect of human IgG and fibrinogen on Staphylococcus aureus intraperitoneal infection in mice.

Human serum and plasma have been demonstrated to enhance mortality in Staphylococcus aureus intraperitoneal infection in mice. Two different mechanisms seem to be involved. The effect of serum could be removed by adsorption to S. aureus protein A coupled to Sepharose 4 B and could be reconstituted by the addition of human IgG to IgG-depleted serum. Plasma diluted 1/10 in combination with purified fibrinogen also enhanced mouse mortality. Both effects could be demonstrated, when a coagulase-free variant of S. aureus was used. The results of viable counts of S. aureus in blood and peritoneum of the mice indicate that the enhancing effect of IgG alone and the enhancing effect of fibrinogen in combination with diluted plasma have different mechanisms.

Animals↗
PubMed1984

Staphylococcus aureus peptidoglycan induces histamine release from basophil human leukocytes in vitro.

Whole killed cells, cell walls, and peptidoglycans of Staphylococcus aureus were found to release histamine from human leukocytes and isolated rat mast cells in vitro. The histamine-releasing capability increased in the order of whole bacteria, cell walls, and peptidoglycans. Peptidoglycan was found to release histamine by a nonimmunological mechanism, as demonstrated by release in cells deprived of surface immunoglobulins, whereas whole bacteria and cell walls seemed to operate both by immunological and nonimmunological mechanisms. Histamine release was not a specific property of S. aureus; a wide range of whole bacterial species had this activity. We suggest that peptidoglycan may be a common factor responsible for histamine release by different bacteria.

Basophils↗
PubMed1984

Methodological aspects of Staphylococcus aureus peptidoglycan serology: comparisons between solid-phase radioimmunoassay and enzyme-linked immunosorbent assay.

In the present studies we compared the ability of two commonly used assays, solid-phase radioimmunoassay and enzyme-linked immunosorbent assay (ELISA), to detect human antibodies to Staphylococcus aureus peptidoglycan. ELISA was superior, with a reproducibility of 12.0%, as compared with 18.1% in solid-phase radioimmunoassay. Much lower serum dilutions could be used in ELISA. We also studied the effects of solubilizing the antigen by lysostaphin, lysozyme, or ultrasonication. Lysostaphin-treated peptidoglycan cannot be recommended since solid-phase radioimmunoassay could not distinguish positive from negative serum samples with this preparation. On the other hand, the sensitivity in both assays was high when peptidoglycan treated with lysozyme for 240 min or with ultrasonication for 30 min was used as antigen. The interassay correlation between solid-phase radioimmunoassay and ELISA was slightly better with sonicated peptidoglycan (correlation coefficient = 0.94, P less than 0.01), as compared with lysozyme-treated peptidoglycan (correlation coefficient = 0.76, P less than 0.01). We recommend the ELISA with sonicated peptidoglycan as antigen for use in routine serology.

Adult↗
PubMed1984

Recurrent staphylococcal furunculosis: antibody response against Staphylococcus aureus.

The serum antibody response against staphylococcal antigens was investigated by crossed immunoelectrophoresis in 79 patients with recurrent staphylococcal furunculosis. The levels of precipitating antibodies were significantly higher than in normal controls. Patients increased their antibody levels during an acute exacerbation. It was not possible to differentiate between a severe and a mild infection by means of antibody level.

Adult↗
PubMed1984

Current patterns of bacterial infection in myelomatosis.

Bacterial infections were registered in 39 patients with myelomatosis during 18 months in a prospective study. The infection incidence was 0.80 infections per patient year. 81% of a total of 32 isolates were gram-negative. Urinary tract infections due to Escherichia coli were the most frequent infections. Pneumonia due to Streptococcus pneumoniae were infrequently seen compared to previous studies. Hence, the etiologic spectrum has clearly shifted from gram-positive to gram-negative bacteria in these patients. 53% of all infections were hospital-acquired, and most of these were preceded by instrumentation of the urinary tract or indwelling venous catheters. The infections were nosocomial in 7/9 cases of septicemia registered. All 4 patients who died of infection, suffered from hospital-acquired infections. Patients who attracted infections had significantly higher serum creatinine levels and higher mortality compared to the rest of the patients.

Aged↗
PubMed1983

Antibody response to pneumococcal vaccination in patients with myelomatosis.

17 patients with myelomatosis were vaccinated with a 14-valent pneumococcal capsular polysaccharide vaccine. In comparison to 12 healthy controls, they had statistically significant lower combined geometric mean antibody concentrations (the geometric means of all 14 antigens), both before and 4 weeks after the immunization. Mean antibody increases, however, were remarkably similar in the 2 groups. After 18 months the geometric mean antibody concentrations of the patient group had returned to preimmunization levels or lower for 7 out of 14 antigens. 1 case of pneumococcal bacteraemia occurred in the patient group 8 1/2 months after vaccination in spite of a significant initial antibody response against the infecting serotype 23 F. Pneumococcal vaccination in patients with myelomatosis appears to yield subnormal antibody responses and therefore probably insufficient protection against pneumococcal infection.

Aged↗
PubMed1983

Solid-phase radioimmunoassay of immunoglobulin G antibodies to Staphylococcus aureus peptidoglycan in patients with staphylococcal infections.

A solid-phase radioimmunoassay (SPRIA) for determination of antibodies against S. aureus peptidoglycan was used for serological diagnosis of staphylococcal infections. Elevated IgG antibody levels were found in 21/21 patients with S. aureus endocarditis and in 10/24 patients with S. aureus septicemia. Two patients with streptococcal and one patient with pneumococcal septicemia showed elevated antibody levels as well, probably due to cross reactions between peptidoglycans of different bacterial species. In cases of chronic osteomyelitis caused by S. aureus, 12/33 patients showed elevated antibody levels while all patients with recurrent furunculosis had normal antibody levels. Anti-peptidoglycan antibodies were also found in all healthy controls (n = 160) but at lower levels. This might explain the rapid booster response of IgG antibodies found in 73 per cent of patients with S. aureus endocarditis already within 10 days after the first symptoms. The best clinical value of the assay seems to be in separating S. aureus endocarditis from uncomplicated septicemia.

Adolescent↗
PubMed1983

Crossed immunoelectrophoretic analysis of Legionella pneumophila serogroup 1 antigens.

By crossed immunoelectrophoresis, 85 different antigens were demonstrated in sonicated preparations of Legionella pneumophila serogroup 1 (Lp1). The precipitin patterns of 82 anodic-migrating antigens were numbered and were designated the Lp1 reference system. Eleven antigens were stable to boiling, and seven of these were shown to be surface antigens. One heat-stable surface antigen (antigen no. 61) was highly reactive with limulus amoebocyte lysates and formed a precipitin resembling lipopolysaccharide. Serum from an isolation confirmed case of Lp1 infection and serogroup-specific rabbit antiserum reacted specifically with antigen no. 61, which was designated the serogroup-specific antigen. Normal human and rabbit sera commonly had antibodies to antigen no. 66 of the Lp1 reference system. This antigen is antigenically related to the "common antigen" of Pseudomonas aeruginosa.

Animals↗
PubMed1983

Cross-reactions between Legionella pneumophila (serogroup 1) and twenty-eight other bacterial species, including other members of the family Legionellaceae.

Cross-reactions between Legionella pneumophila serogroup 1 and 28 other bacterial species were studied by various quantitative immunoelectrophoretic techniques. A sonicated L. pneumophila antigen and purified homologous rabbit antibody were used as a reference system. Few antigens (0 to 6) cross-reacted with non-Legionellaceae, but two were found in nearly all gram-negative bacteria tested (antigens no. 1 and 66). Antigen no. 66 of the L. pneumophila reference system was shown to be antigenically similar to the "common antigen" of Pseudomonas aeruginosa reported in many gram-negative bacteria. Greater than 85% of the antigens from L. pneumophila serogroup 1 cross-reacted with the other six serogroups of L. pneumophila. By contrast, Fluoribacter (Legionella) bozemanae, F. (L.) dumoffii, F. (L.) gormanii, and Tatlockia (Legionella) micdadei cross-reacted with only 45, 53, 39, and 43% of the reference system antigens, respectively. The antigenic relatedness of members of the Legionellaceae, expressed as a matching coefficient, is discussed in terms of its taxonomic significance. Serogroup-, genus-, and family-specific antigens are identified in the L. pneumophila reference system.

Antigens, Bacterial↗
PubMed1983

Staphylococcus aureus endocarditis in Denmark 1976-1981.

Clinical and bacteriological information on Staphylococcus aureus endocarditis from hospitals all over Denmark in the period 1976-1981 was reviewed in 119 cases, 61 females and 58 males. Patient ages ranged from 16 days to 85 years, with a median age of 63 years. The overall mortality was 71%. The mortality correlated significantly with such factors as age, hospital-acquired infections and resistance to penicillin in infecting strains. Hospital-acquired infections occurred in 38% of the patients. The distribution of phage types among strains isolated from blood cultures from patients with endocarditis corresponded to that of strains from other septicaemia cases. Group I and group III strains and strains of the 94, 96 complex comprised 74% of the phage types of the present material. Infections of the skin were the most common portal of entry for the infecting strains. Apart from drug addicts, of which 11 cases were included, mortality did not correlate with the presence of any underlying diseases.

Adolescent↗
PubMed1983

Serological diagnosis of Staphylococcus aureus septicaemia and endocarditis by means of crossed immuno-electrophoresis.

The diagnostic sensitivity and specificity were determined for serological diagnosis of Staphylococcus aureus endocarditis and septicaemia by means of crossed immuno-electrophoresis with intermediate gel. The antibody responses to S. aureus antigens in sera from 19 patients with S. aureus endocarditis and 51 patients with S. aureus septicaemia were compared with findings in 30 patients with non-S. aureus endocarditis and 30 patients with non-S. aureus septicaemia. Two of 55 S. aureus antigens, no. 18 (cross-react serologically with cell wall teichoic acid) and no. 46 of the reference pattern, were useful for serological diagnosis. The precipitin score, taking into account both the total number of precipitins and their titres, was the most useful diagnostic criterion. The present method can be used in selected cases to discriminate between S. aureus and non-S. aureus endocarditis. In cases with septicaemia only a positive test is of clinical value.

Adolescent↗
PubMed1982

Hospital-acquired infections in a burns unit caused by an imported strain of Staphylococcus aureus with unusual multi-resistance.

During the past year five patients from countries in the Middle East admitted to a burns unit were found to harbour a strain of Staphylococcus aureus with unusual multi-resistance to antibiotics. The admission of the first patient was followed by an outbreak of infection with this strain involving ten patients in the unit. In addition five staff members were found to be nasal carriers of the strain. As a result of this incident, the following four patients admitted to the unit were isolated on admission and the spread of their strans was thus prevented. It is recommended that patients on admission to burns units, or similar departments with patients very susceptible to infection, are isolated until their bacterial floras have been examined.

Anti-Bacterial Agents↗
PubMed1982

Precipitating antibodies against Staphylococcus aureus in serum from patients with staphylococcal osteomyelitis, investigated by means of quantitative immunoelectrophoretic methods.

By means of crossed immunoelectrophoresis, precipitating antibodies against 55 Staphylococcus aureus antigens were investigated in serum from 11 patients with acute osteomyelitis and 47 patients with chronic osteomyelitis. Patients with acute osteomyelitis had an increase antibody response, expressed as a precipitin score, compared to normal persons, while patients with chronic osteomyelitis had an almost normal response. The precipitin score in patients with acute osteomyelitis was significantly higher than in patients with chronic osteomyelitis (p less than 0.01). However, patients with chronic osteomyelitis increased their precipitin score during an active phase of the infection.

Acute Disease↗
PubMed1982

Precipitating antibodies against Staphylococcus aureus in experimental rabbit osteomyelitis, investigated by means of quantitative immunoelectrophoretic methods.

Eight rabbits were infected with Staphylococcus aureus by injection of 1 X 10(8) colony-forming units into the marrow cavity of the tibia. Titres of precipitating antibodies against S. aureus in serum were followed by means of crossed immunoelectrophoresis. Four rabbits infected with the protein A-containing, alpha-toxin negative Cowan I strain developed no signs of infection and only a slight or no antibody response. All 4 rabbits infected with the protein A-free, alpha-toxin-producing Wood 46 strain developed local signs of infection, and 3 of 4 developed roentgenologic signs of osteomyelitis. All 4 rabbits developed a very high level of precipitating antibodies, but after 2-3 months the level of antibodies decreased, although the infection continued.

Animals↗
PubMed1982

Humoral and cellular immunity in typhoid and paratyphoid carrier state, investigated by means of quantitative immunoelectrophoresis and in vitro stimulation of blood lymphocytes.

The humoral and cellular immunity of 8 Salmonella carriers and 9 non-carriers was investigated and compared to findings in normal persons. The antibody response in serum and intestinal secretions was investigated by means of crossed immunoelectrophoresis, and blood lymphocytes were investigated by in vitro stimulation. Both carriers and non-carriers showed increased levels of precipitating antibodies as well as lymphocyte responses, when compared to normal persons. No differences in the antibody responses either qualitatively or quantitatively were found between carriers and non-carriers. Only few precipitins could be detected in intestinal secretions. Lymphocyte responses to S. typhi and S. paratyphi were significantly higher in carriers and non-carriers than in the controls. No significant difference in lymphocyte response to S. typhi, S. paratyphi and mitogens was obtained between carriers and non-carriers. Thus, the carrier state seems not due to detectable major immunodeficiency.

Adult↗