bluuebunny/crossref_metadata_2025 huggingface dataset:
Potentiation of interferon activity by mixed preparations of fibroblast and immune interferon
Authors: Fleischmann W R , Georgiades J A , Osborne L C , Johnson H M
Published: January 2020

Mixed preparations of fibroblast and immune interferons interacted with cells synergistically to cause the development of a much greater level of protection than expected on the basis of their separate activities. This increased level of protection was 5- to 20-fold greater than expected on the basis of a simple additive effect of the interferons. The potentiating factor copurified with both fibroblast interferon and immune interferon as they were partially purified. The potentiation was not an artifact of a more rapid development of immune interferon-induced antiviral resistance in the presence of fibroblast interferon. The results were consistent with the hypothesis that fibroblast and immune interferons mutually potentiate each other, thus supporting the supposition that they have different modes of action.
Effects of low concentrations of zinc on the growth and dimorphism of Candida albicans: evidence for zinc-resistant and -sensitive pathways for mycelium formation
Authors: Bedell G W , Soll D R
Published: January 2020

In this analysis we have examined in detail the effects of low concentrations of zinc on the growth and dimorphism of Candida albicans. Evidence is presented that micromolar concentrations of zinc added to growth cultures grown at 25 degrees C (i) cause a twofold increase in the final concentration of spheres at sationary phase, (ii) result in an asynchronous block in the budding cycle at stationary phase, (iii) completely suppress mycelium formation in two independently isolated human strains which produce low but significant levels of mycelia at stationary phase, and (iv) completely suppress mycelium formation in cultures of mutant M10, in which over 60% of the cells form mycelia at stationary phase. In contrast, micromolar concentrations of zinc do not inhibit mycelium formation induced by releasing cells from stationary-phase cultures into fresh medium at 37 degrees C. In addition, if zinc is present in the growth medium of the initial culture at 25 degrees C, the average time of subsequent mycelium formation after release into fresh medium at 37 degrees C is halved. It is demonstrated that the above effects are specific to zinc. The possibility of alterante pathways for mycelium formation is suggested, and the medical implications of this possibility are discussed.
Large-scale production and physicochemical characterization of human immune interferon
Authors: Langford M P , Georgiades J A , Stanton G J , Dianzani F , Johnson H M
Published: January 2020

Large-scale production of crude high-titered (10(2.3) to 10(4) U/ml) human immune interferon (type II) was carried out in roller bottle cultures of human peripheral lymphocytes by using the T-cell mitogen staphylococcal enterotoxin A. Over 99% of human immune interferon was destroyed by pH 2 or heat at 56 degrees C for 1 h. The interferon was not neutralized by antibody to human leukocyte interferon. The kinetics of development of the antiviral state were slow for immune interferon relative to those for leukocyte interferon. Ultrogel AcA 54 chromatography of crude or the concentrated interferon resulted in two peaks of activity, a major one (87% of recovered activity) with a molecular weight of 40,000 to 46,000 and a minor peak of molecular weight 65,000 to 70,000. The column elution buffer consisting of 18% ethylene glycol and 1 M NaCl in phosphate-buffered saline resulted in at least 100% recovery of added interferon. The data suggest, then, that the interferon produced under large-scale conditions was immune (type II). The efficiency of the production was comparable to that described for large-scale production of human leukocyte interferon. Our large-scale production system for human immune interferon offers a feasible approach to preparation of large quantities of purified immune interferon for structure studies, antibody production, and clinical application.
Chemotaxigenesis by cell surface components of Staphylococcus aureus
Authors: Schmeling D J , Peterson P K , Hammerschmidt D E , Kim Y , Verhoef J , Wilkinson B J , Quie P G
Published: January 2020

In an attempt to delineate the staphylococcal cell surface components of importance in chemotaxigenesis, we incubated intact Staphylococcus aureus H, crude cell walls, purified cell walls, peptidoglycan, teichoic acid, and cell membranes with human sera. The results reported indicate that both crude cell walls and purified cell walls, as well as peptidoglycan, were potent chemotaxigens. These particles led to the generation in normal human serum of a factor that was chemotactic for human polymorphonuclear leukocytes. Cell wall peptidoglycan and teichoic acid both appeared to play a role in chemotaxigenesis. Kinetic studies employing C2-deficient serum and immunoglobulin-deficient serum revealed that optimal chemotaxigenesis required the presence of an intact classical complement pathway, as well as antibody. Granulocyte aggregometry studies showed that significant levels of C5a were generated in normal serum and that this activated complement component appears to be a major chemotactic factor produced in serum upon interaction with staphylococcal cell wall components.
Changes in immunoferritin labeling of Rickettsia tsutsugamushi after serial cultivation in 60Co-irradiated BHK cells
Authors: Rikihisa Y , Rota T , Lee T H , MacDonald A B , Ito S
Published: January 2020

The immunolabeling characteristics of Rickettsia tsutsugamushi (Gilliam strain) were examined by using a purified immunoglobulin G fraction of antibody to R. tsutsugamushi raised in rabbits. Formalin-fixed rickettsiae were reacted with this antibody and then with ferritin-conjugated goat anti-rabbit Fc antibody. R. tsutsugamushi cultivated in yolk sacs was used to raise antibody for this study. When rickettsiae in BHK-21 cells infected from yolk sac seed material were immunoferritin labeled, the binding of ferritin was found to be dense and uniform on the outer surface of the rickettsiae in disrupted host cells. Immunolabeling of purified suspensions of extracellular rickettsiae resulted in the uniform ferritin labeling of the microorganism. Aggregation of these rickettsiae by antibody appeared to depend upon the purity of the pellets. Immunoferritin labeling examined at high magnification revealed ferritin very close to the outer dense leaflet of the outer membrane. On some rickettsiae or on focal sites of others, the labelin; was several ferritin particles thick, suggesting the presence of a thick coating. The immunoferritin labeling of R. tsutsugamushi during successive serial passages in BHK-21 cells revealed decreased labeling with each passage, and by the 10th passage there was no detectable labeling. However, these rickettsiae inoculated back into yolk sacs regained their immunoferritin labeling. R. tsutsugamushi passed back into yolk sacs after four serial propagations in BHK-21 cells regained their labeling on the first passage in yolk sacs. However, rickettsiae from the 20th serial passage in BHK-21 cells required five passages in yolk sacs to reestablish their previous labeling affinity. Rickettsiae which did not label after 20 passages in BHK cells regained some of their labeling characteristics when sonicated. Antibody against rickettsiae cultivated in BHK-21 cells continued labeling rickettsiae even after 9 serial passages in BHK-21 cells.
Opsonization of Four
Bacteroides
Species: Role of the Classical Complement Pathway and Immunoglobulin
Authors: Tofte Robert W. , Peterson Phillip K. , Schmeling David , Bracke James , Kim Youngki , Quie Paul G.
Published: January 2020

Previous investigators have suggested that opsonization of two
Bacteroides
species is mediated exclusively by the alternative complement pathway and requires immunoglobulins. In this study, the nature of the opsonic factors in nonimmune human serum for four species of
Bacteroides
was investigated by measuring uptake of [
3
H]thymidine-labeled bacteria by human polymorphonuclear leukocytes. Normal human serum, C2-deficient serum, immunoglobulin-deficient serum, and serum chelated with ethylene glycol-bis(β-aminoethyl ether)-
N
,
N
-tetraacetic acid (EGTA), MgEGTA, and ethylenediaminetetraacetic acid (EDTA) were used as opsonic sources. Heat inactivation of each of these sera significantly reduced its opsonic activity for all four
Bacteroides
species, suggesting that serum complement was essential for effective opsonization. All strains were opsonized in the absence of the classical complement pathway; however, kinetics studies revealed that opsonization proceeded at a significantly faster rate when the classical complement pathway was intact. Although two strains were opsonized in immunoglobulin-deficient sera, opsonization was less efficient and appeared to occur via the alternative complement pathway. Unexpectedly, all strains were well opsonized by the classical complement pathway in 10% serum which had been effectively chelated with EGTA or EDTA. The explanation for this finding is unknown; however, it is possible that cell wall cations of
Bacteroides
species may participate in the activation of complement in chelated serum, resulting in effective opsonization. It was also found that
Bacteroides
, when incubated with an
Escherichia coli
strain in normal serum, could compete for opsonins and thereby reduce phagocytosis of
E. coli.
It is possible that competition for opsonins among bacterial species contributes to the synergistic role these organisms share in mixed floral infections.
Attachment of Proteus mirabilis to human urinary sediment epithelial cells in vitro is different from that of Escherichia coli
Authors: Edén C S , Larsson P , Lomberg H
Published: January 2020

The in vitro attachment of 335 Proteus mirabilis strains from various human sources to human urinary tract epithelial cells was measured. No significant difference in adhesive capacity was found between P. mirabilis strains isolated from the blood of 89 patients with bacteremia, the stools of 36 healthy subjects and 56 patients with diarrhea, and the urine of 62 adults and 92 children with bacteriuria. High mean adhesion values were observed in all groups. The P. mirabilis strains attached only to squamous cells and not to transitional epithelial cells, whereas most of the Escherichia coli strains tested attached to both cell types; strains from patients with acute pyelonephritis attached more often than those from patients with acute cystitis or asymptomatic bacteriuria. The attachment of P. mirabilis to squamous epithelial cells was high about day 15 of the menstrual cycle of the epithelial cell donor, but low at the beginning and the end of the cycle. In contrast, the attachment of E. coli to squamous and transitional epithelial cells did not vary significantly with the menstrual cycle of the cell donor. Differences in adhesion characteristics of E. coli and P. mirabilis may relate to the differences in clinical appearance of urinary tract infections produced by the two organisms.
Breast milk lymphocyte response to K1 antigen of Escherichia coli
Authors: Keller M A , Turner J L , Stratton J A , Miller M E
Published: January 2020

Comparison milk and blood lymphocyte blastogenic responses to the K1 antigen of Escherichia coli and lipopolysaccharide (LPS) from E. coli O127,B8 were examined in 16 postpartum women by [3H]thymidine uptake. Rabbit hemolysincoated sheep erythrocyte monolayers were used to deplete macrophages from milk lymphocyte preparations and to enrich for T lymphocytes in order to make milk preparations more comparable to blood preparations. Response was defined as a stimulation index of greater than or equal to 2.0. There was no evidence of selective response to K1 antigen by milk lymphocytes, since both blood and milk lymphocytes responded in four women and neither blood nor milk lymphocytes responded in nine. Milk lymphocytes alone responded to K1 in one woman, whereas blood lymphocytes alone responded in two women. Additional nonpaired milk or blood cultures were available from three women. None of these responded to K1 antigen. Corresponding lymphocyte cultures were stimulated with LPS. A positive K1 response was always accompanied by an LPS response, and the LPS response correlated with the K1 response in 17 of 19 women. Stool cultures examined with an antiserum agar showed no correlation between the presence of K1 E. coli in the stool and milk or blood lymphocyte response to K1 antigen. In the system used here, no selectivity of response of breast milk lymphocytes to K1 antigen was noted.
Analysis of the Lytic Step in the Herpes Simplex Virus Antibody-Dependent Cellular Cytotoxicity System
Authors: Shore Steven L. , Romano Thomas J.
Published: January 2020

An antibody-dependent cellular cytotoxicity (ADCC) system in which herpes simplex virus-infected Chang liver cells are used was assessed for its dependency on cellular energy, ribonucleic acid and protein synthesis, and cytoskeletal structures such as microfilaments and microtubules. The cytotoxic reaction was only slightly inhibited when glycolysis was blocked in a glucose-free medium containing 10
−2
M 2-deoxy-
d
-glucose. It was more substantially inhibited when respiration was blocked with 10
−2
M sodium azide. The reaction was totally ablated, however, only when both glycolysis and respiration were suppressed. This inhibitory effect of energy deprivation was mediated solely at the level of the effector cell. Ribonucleic acid synthesis or protein synthesis by the effector cells was not required, as shown by the fact that neither actinomycin D, cycloheximide, nor emetine significantly inhibited ADCC. The ADCC reaction was partially inhibited by cytochalasin B, whose inhibitory effect was rapidly reversible, and was completely and irreversibly inhibited by cytochalasin A. Cytochalasin A acted on the effector cells rather than the target cells. The reaction was also partially inhibited by colchicine, whose inhibitory effect was directed solely against the effector cells and was slowly reversible. The inhibitory effects of cytochalasin B and colchicine, when used in tandem at submaximal inhibitory concentrations, were slightly more than additive. The results suggest a cooperative role for effector cell microfilaments and microtubules in mediating ADCC. Kinetic studies of ongoing herpes simplex virus ADCC reactions after initial centrifugation showed that the lytic step requires expenditure of metabolic energy as well as intact function of both microfilaments and microtubules. These findings, in concert with previous data, indicate that the ADCC process against herpes simplex virus-infected Chang liver cells can be resolved into adhesion and lytic steps. The lytic step can be readily distinguished from the adhesion step by its increased sensitivity to low ambient temperature or metabolic energy deprivation, its sensitivity to thermal inactivation, its requirements for extracellular divalent cations, and its dependence on normal function of both microfilaments and microtubules.
Immunological properties of Actinomyces viscosus: comparison of blastogenic and adjuvant activities
Authors: Chen P , Farrar J J , Genco R J
Published: January 2020

A water-soluble extract of Actinomyces viscosus was tested for its capacity to induce deoxyribonucleic acid synthesis in spleen cells from normal mice and to augment the in vitro antibody-forming cell (AFC) response to the T-cell-dependent antigen, sheep erythrocytes (SRBC) by T-cell-deficient adherent spleen cell monolayers from the same mice. Our results indicated that the water-soluble extract induced an in vitro blastogenic response, as assessed by tritiated thymidine incorporation into mouse spleen cells. The water-soluble extract also augmented the antibody response to SRBC. However, after fractionation of the water-soluble extract on Biogel P-300, not all of the fractions induced a blastogenic response and augmented an AFC response to SRBC. This difference in the ability of A. viscosus fractions to induce in vitro responses suggests that the water-soluble extract has multiple immunological properties. Chemical analysis of the water-soluble extract indicated an enrichment for amino acids and amino sugar common to peptidoglycan.
Rapid expulsion of Trichinella spiralis: coinduction by using antigenic extracts of larvae and intestinal stimulation with an unrelated parasite
Authors: Bell R G , McGregor D D
Published: January 2020

The injection of cell-free extracts of larval Trichinella spiralis with Freund complete adjuvant immunized rats against a challenge infection with T. spiralis. Protection was expressed by a reduction of adult worms in the intestines 8 days after a challenge infection. The quantitatively more important rapid expulsion reaction could also be produced by immunization with antigen, provided immunized rats were also given an intestinal priming infection with adult Trichinella spiralis or an unrelated nematode, Heligmosomoides polygyrus. These parasites stimulated a local change in the intestine that synergistically interacted with immunity to give up to 90% protection through the rapid expulsion response. Intestinal priming had to follow antigen administration by not less than 5 days and was optimal when 10 days elapsed. These experiments provide evidence for an immunological component in the rapid expulsion process. In addition, the technique suggests that the utilization of intestinal priming may provide a new approach for the development of intestinal antihelminth vaccines.
Determinants that increase the serum resistance of Escherichia coli
Authors: Taylor P W , Robinson M K
Published: January 2020

The rfb locus, determining biosynthesis of O8-specific lipopolysaccharide side chains, was transferred to a rough mutant of Escherichia coli; recombinants producing a complete lipopolysaccharide were more resistant to the complement-mediated bactericidal action of human serum than the rough recipient. Inheritance of the his-linked genes for K27 antigen production did not alter the response to serum. The serum resistance of strains carrying O8 side chains, but not of strains with incomplete lipopolysaccharides, was further increased by inheritance of plasmids R1 and NR1.20
Effects of route and time of administration of antiserum on protection of mice from lethal infection due to group B Streptococcus type III
Authors: Stanton B F , Baltimore R S , Shedd D G
Published: January 2020

The present study examines a mouse model of infection due to group B Streptococcus serotype III (GBS-III) as to the route and timing of antiserum administration for protection and quantitation of bacteremia with and without antiserum. Data for these parameters are contrasted with those after challenge with serotype Ia of group B Streptococcus (GBS-Ia). An intraperitoneal injection of GBS organisms and protective antiserum from a single syringe can be used to create an animal model of disease. Intraperitoneal injection of GBS-III resulted in bacteremia at 0.5 h both in animals who did not receive antiserum (17.4 X 10(2) +/- 7.6 X 10(2) colony-forming units per ml of blood samples) and in animals who received antiserum (19.3 X 10(1) +/- 6.8 X 10(1) colony-forming units per ml). Although intraperitoneal injection of GBS-Ia also resulted in bacteremia evident by 0.5 h in unprotected animals (30.1 X 10(2) +/- 3.8 X 10(2) colony-forming units per ml), no bacteremia occurred in protected recipients of this organism. Bacteremia due to GBS-Ia and GBS-III logarithmically increased until at least 7 h. Bacteremia due to GBS-III in protected animals was cleared by 24 h. Protection against GBS disease did not require simultaneous or proximate administration of the organism and the antiserum. Mice could be protected from death after intraperitoneal challenge with GBS-III or GBS-Ia by antiserum administered intravenously or intraperitoneally from 6 h before to 2.5 h after challenge.
Cryoglobulins, circulating immune complexes, and complement activation in cerebral malaria
Authors: Adam C , Géniteau M , Gougerot-Pocidalo M , Verroust P , Lebras J , Gibert C , Morel-Maroger L
Published: January 2020

A total of 32 patients with Plasmodium falciparum malaria were studied. Of these, 23 had benign infections, and 9 had typical cerebral malaria. Cryoglobulins, circulating immune complexes detected by a C1q-binding assay, and hypocomplementemia were found in eight of nine patients with cerebral malaria. Raised levels of complement component 3 breakdown products (C3d) were found in the seven patients tested. Peak levels of circulating immune complexes and C3d were associated with thrombocytopenia. In contrast, in patients with benign Plasmodium falciparum malaria, cryoglobulins and circulating immune complexes were found only in 3 of 23 patients. Similarly, hypocomplementemia was detected only in 5 of 23 patients. These observations suggest that the intensity of the immune response and of the associated complement activation may be important factors in the pathogenesis of cerebral malaria.
Energy-independent uptake of iron from citrate by isolated outer membranes of Neisseria meningitidis
Authors: Simonson C , Trivett T , DeVoe I W
Published: January 2020

Cyanide-poisoned Neisseria meningitidis SD1C cells rapidly took up 55Fe from iron-citrate complexes during the first 2 min, after which no further iron was accumulated. [14C]citrate was not taken up concomitantly with 55Fe by these cells. The 55Fe taken up by the poisoned cells was found in the membrane fraction after cells were broken; 70% of the radioactivity was distributed in the outer membrane, and 30% was in the inner membrane. Isolated outer membranes from iron-starved cells were as capable of iron uptake from citrate as intact cells were. As with whole cells, [14C]citrate was not taken up by isolated outer membranes. A polyacrylamide gel electrophoresis analysis of the proteins from citrate-dialyzed outer membranes after the uptake of 55Fe revealed that the radioactivity was associated with a major band of 36,500 molecular weight.
Colicin V production by clinical isolates of Escherichia coli
Authors: Davies D L , Falkiner F R , Hardy K G
Published: January 2020

Strains of Escherichia coli isolated from random fecal samples, urines of hospitalized and nonhospitalized patients who had urinary tract infections, and blood of patients with septicemia were examined for colicin V production. The percentage of ColV+ strains isolated from blood (31.6%) or from urines of hospitalized patients with urinary tract infections (26.2%) was significantly greater (P less than 0.01) than the percentage isolated from feces (13.6%). The colicin V immunity determinant of ColV,I-K94 conferred immunity to 26% of the type V colicins produced by clinical isolates. Of the ColV+ strains studied, 63.6% produced at least one other type of colicin.
Animal model for anaerobic lung abscess
Authors: Kannangara D W , Thadepalli H , Bach V T , Webb D
Published: January 2020

There are no satisfactory animal models for the study of anaerobic lung abscess. Aspiration of food, gastric mucin, or hydrochloric acid, or any combination of these, along with oropharyngeal bacteria, is commonly believed to cause aspiration pneumonia and lung abscess. In the animal model described, none of the adjuvants was effective in producing anaerobic lung abscesses. Anaerobic bacteria derived from dental scrapings of a healthy adult (Peptococcus morbillorum, Fusobacterium nucleatum, Eubacterium lentum, and Bacteroides fragilis), when inoculated transtracheally without any adjuvants into New Zealand male white rabbits, consistently produced lung abscesses. Neither B fragilis by itself nor a mixture of P. morbillorum, F. nucleatum, and E. lentum without the addition of B. fragilis produced lung abscesses. The bacterial isolates used in this study were stored in prereduced chopped-meat-glucose medium and subcultured several times and were found effective in reproducing anaerobic lung abscesses repeatedly. This animal model is suitable for the study of pathogenesis, diagnosis, and treatment of B. fragilis-associated anaerobic lung abscess.
Type-specific reovirus antiserum blocks the cytotoxic T-cell-target cell interaction: evidence for the association of the viral hemagglutinin of a nonenveloped virus with the cell surface
Authors: Finberg R , Weiner H L , Burakoff S J , Fields B N
Published: January 2020

It has previously been demonstrated that spleen cells from mice immunized with reovirus type 1 or 3 generate virus-specific cytotoxic T lymphocytes (CTL) after in vitro restimulation. Such cytotoxic T cells lyse H-2 identical targets that are infected with the appropriate reovirus type. Viral recombinants were used to demonstrate that the S1 gene is the predominant viral gene determining the specificity of the CTL. Reoviruses are nonenveloped, non-membrane-maturing viruses; therefore, it was important to determine whether viral products were being recognized by CTL on the surface of target cells. Antiserum blocking was utilized to investigate this issue. Using viral recombinants and antisera to reoviruses types 1 and 3, we were able to demonstrate that the major viral antigen recognized by the CTL on the target cell surface is the sigma 1 polypeptide encoded by the S1 genome segment. Thus, viral antigens on the target cell membrane seem to be important in the CTL response to a nonenveloped, non-membrane-maturing virus.
Diminished neutrophil oxidative metabolism after phagocytosis of virulent Salmonella typhi
Authors: Kossack R E , Guerrant R L , Densen P , Schadelin J , Mandell G L
Published: January 2020

The interactions of human polymorphonuclear neutrophils (PMNs) with virulent and avirulent strains of Salmonella typhi were examined. Ingestion of the S. typhi strains by PMNs was evaluated with three techniques: visual examination of PMN monolayers (phagocytic index); uptake of radiolabeled S. typhi by PMNs; and removal of S. typhi from the supernatant of suspensions of PMNs and bacteria. All three techniques indicated equivalent phagocytosis of the strains. Postphagocytic PMN oxidative metabolism was quantitated with measurements of oxygen consumption, protein iodination, and chemiluminescence. We found that although PMNs ingested equal numbers of virulent and avirulent S. typhi, those PMNs ingesting the virulent organisms exhibited a significantly smaller increase in postphagocytic oxidative metabolism than PMNs ingesting avirulent S. typhi. Despite this muted oxidative burst the virulent bacteria were killed as well as the avirulent strains. Virulent S. typhi either fail to stimulate receptors that trigger PMN oxidative metabolism or inhibit PMN oxidative metabolism. Our data support the former hypothesis.
Assay of type-specific and type-common antibodies to herpes simplex virus types 1 and 2 in human sera
Authors: Eberle R , Courtney R J
Published: January 2020

A reliable and reproducible method for determining specific reactivity to herpes simplex virus types 1 and 2 (HSV-1 and HSV-2) in human sera has been developed. Human sera were used to immunoprecipitate HSV-specific glycoprotein antigens from both HSV-1- and HSV-2-infected cell extracts. The viral glycoproteins precipitated from these extracts were then analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis to detect specific reactivity of the sera with distinct type-specific antigens of HSV-1, HSV-2, or both as well as with type-common glycoprotein antigens. By examining a large number of human sera, this method was found to be more reliable than the standard microneutralization test in discriminating between single-positive (positive for HSV-1 or HSV-2) and double-positive (positive for HSV-1 and HSV-2) sera.
Immunogenicity of Staphylococcus aureus delta-toxin
Authors: Nolte F S , Kapral F A
Published: January 2020

Studies were conducted to determine the immunogenicity of purified Staphylococcus aureus delta-toxin. Rabbits and guinea pigs immunized with delta-toxin incorporated into a multiple antibody, whereas animals given toxin in saline or toxin in saline with Tween 80 did not produce antibody. The immunoglobulin G (IgG) fraction isolated by chromatography on protein A-Sepharose was examined for the presence of anti-delta-toxin antibody by immunoelectrophoresis, immunodiffusion, quantitative precipitation tests, affinity chromatography, and toxin neutralization tests. Although delta-toxin-specific IgG precipitated the toxin in agar gels, the antibody did not neutralize the toxin's hemolytic activity. Delta-toxin binding to human erythrocyte membranes was demonstrated by indirect immunofluorescent staining of toxin-treated erythrocytes.
Cryptococcal skin test antigen: preparation variables and characterization
Authors: Bennett J E
Published: January 2020

Antigen capable of eliciting delayed hypersensitivity reactions in the skin of sensitized guinea pigs could be extracted from Cryptococcus neoformans cells by stirring the cells from 3 to 5 days in concentrated urea or guanidine. Hydrolysis of urea to ammonia by cryptococcal urease accompanied urea extraction, but alkalinity appeared neither necessary nor sufficient for extraction. Antigen from live cells gave larger delayed skin reactions than did antigen from Formalin-killed cells. Peak skin test reactivity appeared to reside in protein-rich fraction having an elution volume on Sephadex G50 corresponding to a molecular weight of 10(4). Activity precipitated with half-saturated ammonium sulfate and could be detected in a single, narrow, rapidly migrating band on disc electrophoresis. Dialyzable proteinaceous antigen and high-molecular-weight, serologically active polysaccharide were present in the antigen, but not active in the delayed hypersensitivity reactions.
Characteristics of virulence in human isolates of Yersinia enterocolitica
Authors: Schiemann D A , Devenish J A , Toma S
Published: January 2020

Yersinia enterocolitica serotypes O:3, O:8, O:9, O:5,27, O:4,32, and O:21 were virulent as determined by autoagglutination and calcium dependency at 35 degrees C and ability to produce guinea pig conjunctivitis and mouse diarrhea.
Localization of brucella antigens that elicit a humoral immune response in Brucella abortus-infected cells
Authors: Schurig G G , Pringle A T , Breese S S
Published: January 2020

Localization of brucella antigens, to which brucella-infected cattle make antibodies, and the surface characteristics of Brucella abortus smooth strain 19 and rough strain 45/20 were studied by the use of monospecific antisera in absorption tests, electron microscopy, and electrophoretic mobility of organisms in microelectrophoresis. Antigenic determinants of electrophoretically defined antigen A5 were present on the surface of B. abortus rough strain 45/20 organisms, and protein moieties were most probably exposed on the surface of this strain in contrast with smooth strain 19 organisms. Several antigens distinct from the smooth lipopolysaccharide complex, to which brucella-infected cattle make antibodies, were not detected on the surface of smooth organisms. Agglutinating antibodies present in anti-B. abortus strain 19 serum did not bind to all areas on the surface of the smooth cells, suggesting the presence of different antigenic moieties on their surface. It is also postulated that the surface of B. abortus rough strain 45/20 displays receptors able to strongly bind immunoglobulin molecules, as well as other serum components.
Pathogenesis of Herpes simplex virus infections in guinea pigs
Authors: Scriba M , Tatzber F
Published: January 2020

The pathogenesis of herpes simplex virus types 1 and 2 has been studied in guinea pigs after inoculation by various routes (subcutaneous and intradermal infection in footpads and vaginal infection). Clinical observations as well as virus isolation studies are reported. Herpes simplex virus type 2 infection by all three routes of inoculation led to acute primary and recurrent lesions. Virus persisted in the nervous system, particularly in sensory ganglia, and locally at the site of inoculation. Herpes simplex virus type 1 infection induced no or very mild primary symptoms. Recurrent lesions were only observed after intradermal inoculation. Invasion of the nervous system and consequent establishment of latent ganglionic infection was less efficient than after herpes simplex virus type 2 infection. Peripheral persistence was, however, equally common.
Cell-mediated immunity to herpes simplex virus: recognition of type-specific and type-common surface antigens by cytotoxic T cell populations
Authors: Eberle R , Russell R G , Rouse B T
Published: January 2020

In this communication, we examine the specificity of anti-herpes simplex virus (HSV) cytotoxic T lymphocytes (CTL). Serological studies of the two related HSV serotypes (HSV-1 and HSV-2) have revealed both type-specific and cross-reactive antigenic determinants in the viral envelope and on the surface of infected cells. By analysis of cytotoxicity of CTL, generated in vitro by restimulation of splenocytes from mice primed with one or the other HSV serotype, the recognition of both type-specific and cross-reactive determinants on infected target cells by anti-HSV CTL was detectable. Thus, effector cells generated by priming and restimulating with the same virus recognized both type-specific and cross-reactive determinants on target cells infected with the homologous virus, but only cross-reactive determinants on target cells infected with the heterologous HSV serotype. CTL generated by restimulation with the heterologous virus were capable of recognizing only the cross-reactive determinants on either HSV-1- or HSV-2-infected target cells. These results indicate that two subpopulations of CTL exist in a population of anti-HSV immune spleen cells--those which recognize type-specific determinants and those specific for cross-reactive antigenic determinants present on the surface of HSV infected cells. The type-specific subset of anti-HSV CTL was shown to recognize the gC glycoprotein of HSV-1 infected target cells. In addition to the gC glycoprotein, at least one other type-specific surface antigen was also recognized by anti-HSV CTL in addition to the cross-reactive determinants recognized by anti-HSV CTL.
Immunological relatedness among Candida albicans and other pathogenic Candida species
Authors: Hector R F , Lyon F L , Domer J E
Published: January 2020

Membrane-mitochondrial (butanol-hot phosphate-buffered saline) and cytosol (soluble cytoplasmic substances) extracts from seven pathogenic species of Candida were used in in vivo and in vitro immunological assays to study antigenic similarities among the strains with respect to C. albicans. Mice were sensitized with C. albicans serotype A for footpad testing or to provide cells for lymphocyte stimulation assays, and guinea pigs were immunized with whole cells or butanol-hot phosphate-buffered saline extracts of C. albicans to obtain antisera for immunodiffusion assays. When extracts from each of the seven species were used in the assays, they consistently segregated, as determined by statistical or subjective analyses, into three groups. Extracts of C. albicans serotype A or B and C. stellatoidea were the most immunologically reactive in all assays, indicating close similarities between those two species, whereas extracts of C. tropicalis and C. parapsilosis elicited only moderate responses. Extracts from C. krusei, C. guilliermondii, and C. pseudotropicalis were hypo- or nonreactive in the assays, indicating a low level of antigenic relatedness to C. albicans.
Purification and partial characterization of a putative precursor to staphylococcal enterotoxin B
Authors: Tweten R K , Iandolo J J
Published: January 2020

A putative precursor to staphylococcal enterotoxin B (SEB) has been identified as a component of purified membranes from Staphylococcus aureus S6. Agarose gel immunodiffusion analysis of the solubilized membranes demonstrated an immunoreactive protein that formed complete lines of identity with purified extracellular SEB. This putative precursor (pSEB) also had a different electrophoretic mobility from that of extracellular SEB when analyzed by immunoelectrophoresis. When membrane proteins from S6 were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and then transferred to nitrocellulose sheets and probed with I-125 labeled, affinity-purified anti-SEB, the pSEB band was identified. The pSEB was approximately 3,500 daltons larger than extracellular SEB. This component was purified by immunoprecipitation and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Two-dimensional peptide maps of the putative SEB precursor revealed that most of the tryptic peptides were identical to those of mature extracellular SEB. When purified membranes of other SEB+ (DU4916 and 10-275) and SEB- (RN450, RN451, S6R, and FR1100) S. aureus strains were analyzed by the nitrocellulose blot procedure, only the SEB+ strains contained this putative SEB precursor on their membranes.
Phage-host interactions and the production of type A streptococcal exotoxin in group A streptococci
Authors: McKane L , Ferretti J J
Published: January 2020

The infection of Streptococcus pyogenes nontoxigenic strain T 253 with bacteriophage T12 to form lysogen T 253 (T12) resulted in the production of type A streptococcal exotoxin (erythrogenic toxin or streptococcal pyrogenic exotoxin). Two lines of evidence indicated that lysogeny per se was not sufficient to promote toxigenic conversion of strain T 253. First, a virulent mutant of phage T12, unable to form stable lysogens, was able to affect type A exotoxin production by strain T 253. An unrelated virulent phage A25 did not affect type A exotoxin production after infection of strain T 253. Second, the temperate phage H4489A, which established stable lysogens with strain T 253 did not promote type A exotoxin production. These results suggest that there is a strain specificity to the phage-host interaction which affects type A exotoxin synthesis. Additional evidence is presented which indicates that type A streptococcal exotoxin was not a structural component of phage T12.
Murine cytomegalovirus stimulates natural killer cell function but kills genetically resistant mice treated with radioactive strontium
Authors: Masuda A , Bennett M
Published: January 2020

Treatment of C3H/St mice with 100 microCi of 89Sr weakened their genetic resistance to murine cytomegalovirus (MCMV) infection. The criteria utilized to detect increased susceptibility were: (i) survival of mice; (ii) numbers of MCMV-infected cells in the spleens and liver; and (iii) serum glutamic pyruvic transaminase levels. The natural killer (NK) cell activity of spleen cells from mice treated with 89Sr is very low. However, the NK activities of spleen cells of both normal and 89Sr-treated mice were greatly augmented 3 days after infection with MCMV. These NK cells lysed a variety of tumor cells and shared several features with conventional NK cells, but were not lysed by anti-Nk-1.2 serum (specific for NK cells) plus complement. Splenic adherent cells did not lyse tumor cells themselves but were necessary for the stimulation of NK cells by MCMV. The paradox of high NK cell function and poor survival in 89Sr-treated mice infected with MCMV was a surprise. We conclude that these augmented NK cells, of themselves, cannot account for the genetic resistance of C3H/St mice to infection with MCMV.
Flagellar preparations from Pseudomonas aeruginosa: animal protection studies
Authors: Holder I A , Wheeler R , Montie T C
Published: January 2020

Recent reports have suggested that motility is associated with virulence in Pseudomonas aeruginosa. We have confirmed this observation by showing that groups of mice immunized with P. aeruginosa flagellar-antigen preparations display enhanced survival when they are subsequently burned and challenged locally in the burned area with strains of P. aeruginosa. The protection appears to be due to the immobilization of the microorganisms in the burned skin tissue. Liver elongation factor 2 is also protected. The protection afforded by immunization with flagellar-antigen preparations is independent of the somatic antigenic type of the challenging strain but is flagellar-antigen specific. These data suggest that vaccination with flagellar-antigen preparations may provide a viable prophylactic or therapeutic alternative to antibiotic therapy for use in compromised patient population in which P. aeruginosa poses a serious infection threat.
Gamma interferon production by combinations of human peripheral blood lymphocytes, monocytes, and cultured macrophages
Authors: Arbeit R D , Leary P L , Levin M J
Published: January 2020

Mitogen-induced interferon (IFN) production was studied using human peripheral blood mononuclear cells and subpopulations of lymphocytes, monocytes, and cultured macrophages. Cell populations were prepared in suspension to permit quantitative analysis of the interactions among different cell types. After stimulation by staphylococcal enterotoxin A, nylon column-purified lymphocytes produced only 5% as much IFN as the peripheral blood mononuclear cells from which they were prepared. When lymphocytes were supplemented with as little as 2% monocytes, IFN production increased two- to eightfold; with the addition of up to 20% monocytes, IFN production increased further, to levels approximating those of peripheral blood mononuclear cells. Monocytes alone produced no or very little IFN. Macrophages were derived from monocytes by culturing in vitro for 7 days. The addition of 2 to 5% autologous macrophages augmented IFN production to the same extent as 2 to 5% monocytes. However, more macrophages consistently resulted in less, rather than more, IFN, so that lymphocytes with 20% monocytes produced three- to eightfold more IFN than did lymphocytes with 20% macrophages. Thus, whereas the addition of monocytes over a broad dose-response range (2 to 20%) progressively augmented IFN production, macrophages showed an optimal effect at 2 to 5%, with higher percentages being inhibitory. The IFN induced by stimulation with staphylococcal enterotoxin A was characterized as IFN-gamma by its resistance to neutralization by antibody to IFN- alpha and its inability to induce antiviral protection in embryonic bovine trachea cells.
Cross-protection in nonhuman primates against Argentine hemorrhagic fever
Authors: Weissenbacher M C , Coto C E , Calello M A , Rondinone S N , Damonte E B , Frigerio M J
Published: January 2020

The susceptibility of the marmoset Callithrix jacchus to Tacaribe virus infection was investigated to perform cross-protection studies between Junin and Tacaribe viruses. Five marmosets inoculated with Tacaribe virus failed to show any signs of disease, any alterations in erythrocyte, leukocyte, reticulocyte, and platelet counts or any changes in hematocrit or hemoglobin values. No Tacaribe virus could be recovered from blood at any time postinfection. Anti-Tacaribe neutralizing antibodies appeared 3 weeks postinfection. The five Tacaribe-infected marmosets and four noninfected controls were challenged with the pathogenic strain of Junin virus on day 60 post-Tacaribe infection. The former group showed no signs of disease, no viremia, and no challenge virus replication, whereas the control group exhibited the typical symptoms of Argentine hemorrhagic fever, high viremia, and viral titers in organs. Soon after challenge, the Tacaribe-protected marmosets synthesized neutralizing antibodies against Junin virus. These results indicate that the marmoset C. jacchus can be considered an experimental model for protection studies with arenaviruses and that the Tacaribe virus could be considered as a potential vaccine against Junin virus.
Stimulation and suppression of cell-mediated immunity by endosporulation antigens of Coccidioides immitis
Authors: Brass C , Levine H B , Stevens D A
Published: January 2020

The culture filtrate of Coccidioides immitis induced to replicate in its parasitic phase in vitro, termed endosporulation antigens (EA), was assayed for ability to stimulate human lymphocyte blastogenesis in vitro. Stimulation of lymphocytes from skin test-positive healthy subjects by EA was comparable to stimulation by spherulin at optimal dilutions, but EA are 500 times more potent when compared on the basis of weight. Both preparations slightly stimulated lymphocytes from skin test-negative subjects. Heating or dialysis of EA enhanced the effect on skin test-positive subjects, but concentration depressed it. Concentrated EA also depressed nonspecific stimulation caused by phytohemagglutinin. Dialysis of concentrated EA reduced the ability to depress responses. EA from an avirulent strain of C. immitis were as stimulatory as EA from a virulent strain, but concentrating the former did not produce as much depression as concentrating the latter did. A survey of subjects with an optimal dose of EA in lymphocyte transformation showed that EA could separate skin test-positive from -negative subjects as well as spherulin could. The survey also showed that a delta cpm (the difference of incorporated counts of tritiated thymidine per minute in the presence or absence of the reagent) of 10,000 is useful for this separation. These results also indicate the presence of suppressive substances in EA which are only partially dialyzable and which were significantly more prominent in a preparation from the virulent strain.
Biological and immunological properties of Coxiella burnetii vaccines in C57BL/10ScN endotoxin-nonresponder mice
Authors: Williams J C , Cantrell J L
Published: January 2020

Vaccines prepared from Formalin-killed whole cells of Coxiella burnetii (Ohio strain) or from chloroform-methanol residue (CMR) and extract (CME) of such cells were examined for biological and immunological properties in male C57BL/10ScN endotoxin nonresponder mice. Vaccines containing killed whole cells induced a high incidence of gross pathology, as evidenced by liver necrosis, significant splenomegaly, and significant hepatomegaly in mice. The degree and onset of these pathological changes were directly and inversely proportional, respectively, to the dosage of killed organisms administered. Conversely, no splenomegaly, hepatomegaly, or liver necrosis were observed in mice inoculated with CMR or CME. Moreover, killed whole cells were lethal for mice at dosages of 150 to 1,200 micrograms, whereas no deaths were seen in animals given 1,200 micrograms of CMR. In addition, antibodies against phase I and phase II antigens of C. burnetii were detected in the sera of mice inoculated with either whole cells or CMR. Enhanced blastogenic response of splenic lymphocytes was observed when animals were vaccinated with killed whole cells and CMR but not with CME. Moreover, 80 to 90% of mice inoculated with 300 micrograms of the CMR were protected against a lethal challenge of viable rickettsiae, whereas only 50% of the animals given 300 micrograms of killed whole cells were protected. Treatments with CME were essentially without value, since no antibodies were detectable and no significant protection was elicited. Collectively, these results show that, although killed whole cells induced immunity in C57BL/10ScN mice, they induced deleterious tissue reactions, whereas CMR, which also induced immunity, was essentially nondeleterious, based on the parameters employed. These observations suggest that the chloroform-methanol-extractable component(s) is implicated in the deleterious tissue reactions and that the phase I and II antigens may not be involved in the induction of the pathology observed in C57BL/10ScN mice.