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R M McKinney

Publications and source records attributed to R M McKinney.

At least 37 records · Page 2Linked to original sources
PubMed1985

Water-related nosocomial pneumonia caused by Legionella pneumophila serogroups 1 and 10.

Between August 1978 and November 1983, 21 cases of pneumonia caused by Legionella pneumophila occurred in the Leiden University Hospital, mainly among immunocompromised patients. A new serogroup of L. pneumophila, designated serogroup 10 (prototype strain Leiden 1), was isolated from bronchial secretions of four patients, and five patients had serological evidence of infection with this organism. Nine patients had a culture-confirmed infection with L. pneumophila serogroup 1. L. pneumophila serogroups 1 and 10 were also isolated from the hot potable water supply in the building to which 19 of the 21 patients had been admitted. The isolates of L. pneumophila serogroup 1 from patients and the hot potable water were identical in studies with monoclonal antibodies and had the same plasmid profiles. These findings provide further evidence that in our hospital potable water contaminated with L. pneumophila is a source of infection, mainly in immunocompromised patients.

Adult↗
PubMed1985

Genetic structure of populations of Legionella pneumophila.

The genetic structure of populations of Legionella pneumophila was defined by an analysis of electrophoretically demonstrable allelic variation at structural genes encoding 22 enzymes in 292 isolates from clinical and environmental sources. Nineteen of the loci were polymorphic, and 62 distinctive electrophoretic types (ETs), representing multilocus genotypes, were identified. Principal coordinates and clustering analyses demonstrated that isolates received as L. pneumophila were a heterogeneous array of genotypes that included two previously undescribed species. For 50 ETs of L. pneumophila (strict sense), mean genetic diversity per locus was 0.312, and diversity was equivalent in ETs represented by isolates recovered from clinical sources and those collected from environmental sources. Cluster analysis revealed four major groups or lineages of ETs in L. pneumophila. Genetic diversity among ETs of the same serotype was, on average, 93% of that in the total sample of ETs. Isolates marked by particular patterns of reactivity to a panel of nine monoclonal antibodies were also genetically heterogeneous, mean diversity within patterns being about 75% of the total. Both Pontiac fever and the pneumonic form of legionellosis may be caused by isolates of the same ET. The genetic structure of L. pneumophila is clonal, and many clones apparently are worldwide in distribution. The fact that L. pneumophila is only 60% as variable as Escherichia coli raises the possibility that isolates recovered from clinical cases and man-made environments are a restricted subset of all clones in the species as a whole.

Alleles↗
PubMed1985

Use of monoclonal antibodies in an epidemiological marker system: a retrospective study of lung specimens from the 1976 outbreak of Legionnaires disease in Philadelphia by indirect fluorescent-antibody and enzyme-linked immunosorbent assay methods.

Autopsy specimens of lung tissues from 15 patients that contracted legionellosis during the 1976 Philadelphia outbreak of Legionnaires disease were examined for the presence of Legionella organisms and soluble antigens by indirect fluorescent-antibody (IFA) testing and by an enzyme-linked immunosorbent assay (ELISA) with both polyclonal and monoclonal antibodies. In all 15 cases, at least one specimen was positive for Legionella pneumophila serogroup 1 (Lp-1) antigens by a polyclonal antibody ELISA system. Of the 15 cases tested for Lp-1, 9 were positive by a polyclonal antibody IFA test. Nine mouse monoclonal antibodies to Lp-1 gave essentially the same reactivity pattern with extracts from lung tissue homogenates as that obtained with a Philadelphia 1 culture extract by using a monoclonal antibody ELISA system. The same monoclonal antibody panel gave similar results when used in the IFA system with tissue homogenates. Monoclonal antibodies can be used as epidemiological marker systems with both IFA and ELISA testing. This study provides evidence that the 1976 common source outbreak in Philadelphia was probably caused by a single Lp-1 strain. ELISA testing of the soluble antigen of Lp-1 from lung tissue homogenate supernatants was more sensitive than IFA testing of the homogenates and should be extremely useful as either a primary test or as an adjunct to fluorescent antibody testing for legionellosis.

Antibodies, Bacterial↗
PubMed1984

Retrospective examination of lung tissue specimens for the presence of Legionella organisms: comparison of an indirect fluorescent-antibody system with direct fluorescent-antibody testing.

Although direct fluorescent-antibody (DFA) testing has been used successfully for a number of years to detect legionellae in clinical specimens, the number of known species and serogroups of Legionella has now increased to such an extent that the performance of DFA testing for all serological variants is impractical. Lung homogenates that were submitted to the Centers for Disease Control, Atlanta, Ga., from patients with suspected legionellosis, from November 1977 through May 1982, were originally screened by DFA testing. In our study 498 of these lung homogenates were screened by indirect fluorescent-antibody (IFA) testing, using a panvalent antiserum pool containing antibodies to 25 serological variants of Legionella spp. Fluorescein isothiocyanate-labeled goat anti-rabbit immunoglobulin was used as the second antibody of the sandwich system. For positive homogenates, i.e., those containing Legionella organisms, species and serogroup identification was made by IFA staining with polyvalent serum pools and then with monovalent antiserum. Of the 498 homogenates screened, 39 (7.8%) were positive by IFA testing. Four (0.8% of total; 10.3% of positive homogenates) of these had previously been negative by DFA testing, but subsequent testing showed that they contained Legionella organisms for which DFA reagents were not available at the initial screening. All specimens that were positive by DFA testing were also positive by IFA testing. IFA testing with polyvalent antisera is a simple, efficient method which is at least as sensitive as DFA testing and which can be used by clinical laboratories to cope with the increasing number of known serological variants of Legionella spp.

Antibodies, Bacterial↗
PubMed1984

Detection of soluble Legionella pneumophila antigens in serum and urine specimens by enzyme-linked immunosorbent assay with monoclonal and polyclonal antibodies.

Urine and serum specimens from three patients with pneumonia caused by Legionella pneumophila serogroup 1 (Lp1) were tested by enzyme-linked immunosorbent assay (ELISA) for Lp1-soluble antigen. A three-layer direct ELISA with polyclonal antibodies and a four-layer indirect ELISA with both polyclonal and monoclonal antibodies were used. Lp1 antigen was detected in both urine and serum from the three patients. As determined by ELISA, the concentration of antigen was 30- to 100-fold less in serum than in urine collected on the same day. In some instances the indirect ELISA was more sensitive than the direct ELISA, but in others it was less sensitive, depending on the monoclonal antibody used. The subgroup of the infecting Lp1 organism was determined based on antigenic determinants expressed in the urine. This study illustrates the use of serum as well as urine as an antigen reservoir in the laboratory diagnosis of legionellosis by ELISA and the potential for developing more sensitive antigen detection systems by the judicious use of monoclonal antibodies.

Animals↗
PubMed1983

Serogroups of Campylobacter jejuni, Campylobacter coli, and Campylobacter fetus defined by direct immunofluorescence.

Rabbits were inoculated with whole, formalinized Campylobacter jejuni, C. coli, and C. fetus cells; the C. jejuni and C. coli immunogens were identified by their DNA relatedness at the species level to the type strains of C. jejuni or C. coli. The designation C. coli was not used among the other C. jejuni strains; they were classified as hippurate-positive or hippurate-negative C. jejuni. Immunoglobulin G was isolated from the antisera and labeled with fluorescein isothiocyanate. These conjugates defined 10 serogroups of C. jejuni, 2 serogroups of C. coli, and 2 serogroups of C. fetus. Of the 316 strains of C. jejuni tested, 258 (82%) were groupable; 173 were single-serogroup strains, and 85 were multiple-serogroup strains. Of the 226 strains in C. jejuni serogroups, 223 (98.7%) were hippurate positive; of the 27 strains in C. coli serogroups, 26 (96.3%) were hippurate negative. Five strains were equally reactive in immunofluorescent staining with a conjugate for a C. jejuni serogroup and a conjugate for a C. coli serogroup. A total of 58 strains of C. jejuni were ungroupable: 33 (13%) of the 259 hippurate-positive strains and 25 (44%) of the 57 hippurate-negative strains. All 121 strains of C. fetus tested were groupable as A, B, or A:B. The 14 conjugates used to define serogroups of C. jejuni, C. coli, and C. fetus reacted with the flagella but not the cells of other Campylobacter species and were negative on 256 other bacteria from 21 genera.

Animals↗
PubMed1983

Correlation of an expanded direct fluorescent-antibody system with an established passive hemagglutination system for serogrouping strains of Campylobacter jejuni and Campylobacter coli.

Rabbits were inoculated with whole, formalinized cells from eight passive hemagglutination reference strains of Campylobacter. Fluorescein isothiocyanate-labeled immunoglobulin G from these antisera defined seven new direct fluorescent-antibody serogroups of C. jejuni and one new serogroup of C. coli. This expanded the Campylobacter direct fluorescent antibody system to include 17 serogroups of C. jejuni, 3 serogroups of C. coli, and 2 serogroups of C. fetus. We then compared the passive hemagglutination method (57 serotypes) and the direct fluorescent-antibody method (20 serogroups) for typing strains of C. jejuni and C. coli. The data obtained by testing 101 strains by both methods revealed that the two test systems were measuring completely different sets of antigen complexes. The two serogrouping methods were complementary, and their combined use discriminated among strains more effectively than did either method individually.

Campylobacter↗
PubMed1983

Monoclonal antibodies to Legionella pneumophila serogroup 1: possible applications in diagnostic tests and epidemiologic studies.

Monoclonal antibodies were produced against two strains of Legionella pneumophila serogroup 1. A panel of nine monoclonal antibodies were selected for their unique specificities observed in indirect fluorescent antibody tests with 130 strains of L. pneumophila serogroup 1. One monoclonal antibody was reactive with an antigen possessed by 128 of 130 strains. Two major subgroups were identified and 13 different antigen patterns were observed among the 130 serogroup 1 strains.

Animals↗
PubMed1982

Legionella jordanis: a new species of Legionella isolated from water and sewage.

Legionella jordanis sp. nov., as found in two cultures, is described. One isolate was from river water in Indiana and the other isolate was from sewage in DeKalb County, Ga. The former is the type strain of the species, and is designated BL-540 (ATCC 33623). L. jordanis had a partial relationship to L. bozemanii by direct fluorescent-antibody tests but was unrelated to L. pneumophila, L. dumoffii, L. micdadei, L. gormanii, or L. longbeachae. Legionella phenotypic characteristics, including large amounts of branched-chain cellular fatty acids, were shown by the isolates. Studies of DNA relatedness showed that the two cultures of L. jordanis were only slightly related to the six previously described species of Legionella but were more than 90% related to each other. Indirect fluorescent-antibody tests with human sera suggested that unrecognized human infections with L. jordanis may be occurring.

DNA, Bacterial↗
PubMed1981

Optimal fluorescein-to-protein ratios of bacterial direct fluorescent-antibody reagents.

A number of bacterial systems were studied with specific direct fluorescent-antibody reagents prepared from rabbit antiserum fractions and having a wide range of fluorescein-to-protein ratios. These systems included Bacteroides, Bordetella, Clostridium, Escherichia, Legionella, Listeria, Salmonella, Shigella, and Streptococcus. For all systems studied, a fluorescein-to-protein ratio of 30 was optimal for conjugates prepared from ammonium sulfate fractions (greater than 75% gamma globulin) and pure immunoglobulin G desorbed from the Sepharose-bound protein A of Staphylococcus aureus. A pepsin digestion procedure is described that yielded the F(ab')2 piece of pure immunoglobulin G; this was labeled and studied at two fluorescein-to-protein ratios.

Antibodies, Bacterial↗
PubMed1981

Legionella longbeachae species nova, another etiologic agent of human pneumonia.

A new species of bacteria that is an etiologic agent of human pneumonia has been isolated and characterized. Clinical symptoms of infection with this organism are not readily distinguishable from those caused by Legionella pneumophila infection. The organism was isolated from respiratory tract specimens from four patients. Two cases of infection apparently originated in California and one in Georgia, and a fourth was of unknown geographic origin. The name Legionella longbeachae species nova is proposed for this organism. The type strain of L. longbeachae is Long Beach 4 (= American Type Culture Collection 33462).

Aged↗
PubMed1981

Legionellosis.

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Agglutination Tests↗
PubMed1980

Immunologic diagnosis of Legionnaires' disease: cross-reactions with anaerobic and microaerophilic organisms and infections caused by them.

The hundred twenty-four isolates of anaerobic and microaerophilis organisms were examined with a polyvalent direct immunofluorescent antibody (DFA) reagent directed against Legionella pneumophila, serogroups (SG) I-IV. Three of 53 isolates of Bacteroides fragilis cross-reated with the SG I component of the reagent. Rabbit antisera to three SG I strains of L. pneumophila cross-reacted with these three B. fragilis isolates, and cross-reactivity was not due to preexisting rabbit antibodies; antisera to a fourth SG I strain did not cross-react with these isolates. Indirect fluorescent antibody (IFA) examinations of convalescent-phase sera from eight of 41 patients with B. fragilis group infections showed titers of greater than or equal to 1:128 or a fourfold or greater seroconversion against L. pneumophila, SG I. All eight patients had bacteremia due to B. fragilis, but five B. fragilis isolates available from these patients were DFA-negative. Thus, false-positive reactions may result from DFA as well as IFA examinations of sera from patients with B. fragilis infections.

Aerobiosis↗
PubMed1980

Legionella pneumophila serogroup six: isolation from cases of legionellosis, identification by immunofluorescence staining, and immunological response to infection.

Isolates of Legionella pneumophila that are serologically different from strains of serogroups 1 through 5 were obtained from lung biopsy tissue or pleural fluid from three renal transplant recipients in Chicago, Ill. These strains were placed in a newly designated L. pneumophila serogroup, serogroup 6, on the basis of fluorescent-antibody staining characteristics. An L. pneumophila strain obtained from Bethesda, Md., one from Houston, Tex., and one from Oxford, England, also belong to this new serogroup. L. pneumophila serogroup 6 appears to be widely distributed geographically.

Adult↗
PubMed1980

Preservation of nasopharyngeal smears for fluorescent antibody detection of Bordetella pertussis.

Smears from throat and nasal washings seeded with Bordetella pertussis were either treated with aprotinin (a protease inhibitor) or fixed with 1 or 10% Formalin. These smears were stored at 23, 4, and -70 degrees C. Smears were removed and stained with a fluorescent antibody conjugate for B. pertussis at intervals during 22 days of storage. Results indicate that treatment of smears with 4 or 8 U of aprotinin per ml preserved fluorescent antibody staining qualities of B. pertussis for 22 days; fixation with either concentration of Formalin was unsatisfactory.

Aprotinin↗
PubMed1980

The rickettsia-like organisms TATLOCK (1943) and HEBA (1959): bacteria phenotypically similar to but genetically distinct from Legionella pneumophila and the WIGA bacterium.

Two "rickettsia-like organisms," TATLOCK and HEBA, isolated from human blood via guinea pigs and embryonated eggs in 1943 and 1959, respectively, have been cultured on artificial media (charcoal yeast extract agar) for the first time and characterized. TATLOCK and HEBA have identical cultural, biochemical, and antigenic characteristics, as well as identical cellular fatty-acid composition and antimicrobial susceptibilities. These two bacteria have most of the cultural and biochemical characteristics of Legionella pneumophilia, and their gas-liquid chromatography cellular fatty-acid profile is similar to that of WIGA, another bacterium similar to L. pneumophila. Direct fluorescent-antibody reagents prepared for HEBA and TATLOCK gave equal high-titered reciprocal staining and were negative on 220 other bacteria, including L. pneumophila. Deoxyribonucleic acid relatedness studies, however, showed that these bacteria are not genetically related to either L. pneumophila or the WIGA bacterium.

Anti-Bacterial Agents↗
PubMed1980

"Pittsburgh pneumonia agent": a bacterium phenotypically similar to Legionella pneumophila and identical to the TATLOCK bacterium.

The "Pittsburgh pneumonia agent," isolated by Pasculle and co-workers from human lung tissue, has been cultured on artificial media and characterized. The "Pittsburgh" bacterium and the TATLOCK and HEBA bacteria have identical cultural, biochemical, and antigenic characteristics. They also have the same cellular fatty-acid composition, and DNA relatedness indicates that they belong to the same species.

Antigens, Bacterial↗