bluuebunny/crossref_metadata_2025 huggingface dataset:
Temperature-Sensitive Mutants of Influenza A Virus: Production and Characterization of A/Victoria/3/75-
ts
-1[E] Recombinants
Authors: Murphy Brian R. , Hosier Nanette T. , Spring Susan B. , Mostow Steven R. , Chanock Robert M.
Published: January 2020

The Hong Kong/68-
ts
-1[E] virus, which has a 38°C shutoff temperature for plaque formation, has been proposed as a donor of its two
ts
lesions to new variants of influenza A virus that pose an epidemic threat. To further examine whether the acquisition of the two
ts
-1[E] lesions will predictably attenuate new influenza A variants, the HK/68-
ts
-1[E] virus was mated with the A/Vic/3/75 wild-type virus. The Vic/75-
ts
-[E] recombinants that had the two
ts
-1[E] lesions also had a 38°C shutoff temperature. Two Vic/75-
ts
-1[E] recombinants (clones 81 and 113) that had the two
ts
-1[E] lesions, a 38°C shutoff temperature, and the Vic/75 hemagglutinin and neuraminidase glycoproteins were similar to each other and to their
ts
-1[E] parent in the pattern of replication and genetic stability in hamsters. These findings support the hypothesis that the acquisition of the two
ts
-1[E] lesions will predictably attenuate wild-type influenza A virus. Each Vic/75-
ts
-1[E] recombinant virus that possessed only the group 1
ts
-1[E] lesion had a 39°C shutoff temperature. Two of three of the Vic/75-
ts
-1[E] recombinants that had only the group 2
ts
-1[E] lesion had a 39°C shutoff temperature. This suggests that the HK/68-
ts
-1[E] donor virus contains two
ts
genes each of which by itself restricts plaque formation at 39°C and above. The HK/68-
ts
-1[E] parent virus and its Vic/75 recombinant clones 81 and 113 were evaluated in ferret tracheal organ cultures maintained at permissive and restrictive temperatures. The Vic/75-
ts
-1[E] clone 81 differed from its parent and sister clone 113 in that it replicated readily and caused ciliostasis at 37°C, a temperature restrictive for the replication of other
ts
-1[E] recombinants with a 38°C shutoff temperature. The genetic basis underlying this difference was not elucidated.
Temperature-Sensitive Mutants of Influenza A Virus: Evaluation of A/Victoria/3/75-
ts
-1[E] Recombinant Viruses in Volunteers
Authors: Murphy Brian R. , Markoff Lewis J. , Hosier Nanette T. , Rusten Harold M. , Chanock Robert M. , Kendal Alan P. , Douglas R. Gordon , Betts Robert F. , Cate Thomas R. , Couch Robert B. , Levine Myron M. , Waterman Daniel H. , Holley H. Preston
Published: January 2020

The Hong Kong/68-
ts
-1[E] virus and its Udorn/72 and Georgia/74 recombinants, which have a 38°C shutoff temperature and a
ts
lesion(s) on the genes coding for the P3 and NP proteins, were adequately attenuated and immunogenic in adult volunteers who lacked serum hemagglutination-inhibiting antibody (titer, ≤1:8), but who possessed serum neuraminidase-inhibiting antibody. Two Victoria/75-
ts
-1[E] clones that also had a 38°C shutoff temperature and a
ts
lesion(s) on the same two genes were administered to adult volunteers who lacked both serum hemagglutination-inhibiting antibody (titer, ≤1:8) and neuraminidase-inhibiting antibody (titer, ≤1:4). In contrast to the behavior of the earlier
ts
-1[E] recombinants, the Vic/75-
ts
-1[E] recombinants retained the capacity to cause febrile, systemic illness. However, the recombinants were attenuated compared with wild-type virus. The Vic/75-
ts
-1[E] virus vaccinees shed a larger amount of virus for a longer time than the previous
ts
-1[E] vaccinees, but they shed less virus than volunteers infected with wild-type virus. The
ts
-1[E] virus shed retained its
ts
phenotype in most instances and failed to spread to susceptible contacts. Vaccinees were partially protected against homologous wild-type virus challenge. The failure of HK/68, Udorn/72, and Georgia/74
ts
-1[E] vaccinees to develop systemic reactions may reflect the presence of neuraminidase immunity before infection. In this situation, attenuation probably resulted from the degree of defectiveness of the
ts
-1[E] recombinant virus and the existence of neuraminidase immunity in the recipients. The 50% human infectious dose of the Vic/75
ts
-1[E] virus was less than 10
5.2
50% tissue culture infective doses. This suggests that at the time of a pandemic shift involving both the hemagglutinin and neuraminidase glycoproteins, a small amount of live virus vaccine might be effective in initiating infection.
Lysozyme: primary bactericidin in human plasma serum active against Bacillus subtilis
Authors: Selsted M E , Martinez R J
Published: January 2020

The in vitro bactericidal reaction of human plasma serum against Bacillus subtilis was investigated. Human lysozyme was purified to homogeneity, and antiserum was prepared against the enzyme. The anti-lysozyme immunoglobulin G was used as a specific inhibitor in bactericidal and bacteriolytic reactions. It was found that at low serum concentrations lysozyme was the primary bactericide active against B. subtilis. At appreciably higher serum concentrations, a lysozyme-independent bactericidal activity was also demonstrated.
Biological and Physicochemical Characteristics of Four Serotypes of
Salmonella enteritidis
Authors: Reamer R. H. , Affronti L. F. , Blankenship L. C. , Alford J. A.
Published: January 2020

Four serotypes of
Salmonella enteritidis
, Anatum ATCC 9270, Newbrunswick ATCC 1608, Oranienburg 200 E, and Pullorum RM, were studied to determine biological, chemical, or physical differences which might explain variations in
Salmonella
virulence as previously reported by McCullough and Eisele (J. Infect. Dis.
88
:278-289, 1951;
89
:259-265, 1951). These investigators found that serotype Pullorum was significantly less virulent than serotypes Newport, Derby, Barielly, Meleagridis and Anatum when fed to healthy humans. Results of our own experiments showed that serotype Pullorum RM had a generation time approximately twice that of serotype Anatum 9270. The volume of serotype Pullorum was approximately one-half the volume of the other serotypes used (Anatum 9270, Newbrunswick 1608, Oranienburg 200 E, Cubana 12007, and Meleagridis DR). The number of cells required to yield 1 g dry weight was substantially higher for serotype Pullorum RM than for serotypes Anatum 9270, Newbrunswick 1608, and Oranienburg 200 E. The yield of endotoxin per gram dry weight for serotype Pullorum RM averaged 22 mg/g, whereas yields of endotoxin for serotypes Anatum 9270, Newbrunswick 1608, and Oranienburg 200 E averaged 32 to 35 mg/g. The relative abundance of the four major fatty acids (measured by gas chromatography) also showed distinct differences among the serotypes. Pullorum RM contained less lauric and 3-hydroxymyristic acids and more myristic and palmitic acids than the other three serotypes. The identity of 3-hydroxymyristate was confirmed by mass spectroscopy. Serotype Pullorum RM required 10 times more lipopolysaccharides (endotoxin) to obtain a 50% lethal dose in mice than the other three serotypes. When the lipid part was separated from the polysaccharide and solubilized with bovine serum, the 50% lethal dose of serotype Pullorum RM was equal to that of the other three.
Effects of surface-active agents on neutrophil receptors
Authors: Boxer L A , Richardson S B , Baehner R L
Published: January 2020

An easily performed assay to identify the C3b and Fc receptors on human neutrophils was developed. Salmonella typhimurium were treated with fluorescein and then incubated in nonimmune fresh human serum, which led to C3b fixation via activation of the alternative pathway. Similarly, type II pneumococci were treated with fluorescein and opsonized with type-specific rabbit antiserum. Neutrophils bearing C3b and Fc receptors formed rosettes with the respective bacteria, which were easily readable because of their bright fluorescence. Incubation of neutrophils at 37 degrees C with C3-coated bacteria generated 54 +/ 4% C3b rosettes, whereas neutrophils incubated with immunoglobulin G-coated bacteria yielded 75 +/ 7% rosettes. Incubation at 4 degrees C inhibited the formation of C3b rosettes but not Fc rosettes. Heat inactivation of the fresh human serum at 56 degrees C for 30 min completely inhibited the formation of the C3b rosettes, and addition of heat-aggregated immunoglobulin G to the polymorphonuclear leukocyte blocked the ability of the polymorphonuclear leukocyte to bind immunoglobulin G-coated bacteria. Addition of 1.0 mM N-ethylmaleimide, 0.1 mg of trypsin per ml, 10 mM H2O2, O2- generated by xanthine-xanthine oxidase, and 8 times 10(-4) M hydrocortisone inhibited the C3b receptor, but did not inhibit the Fc receptor. In neutrophils, the selective effect of the various inhibitors suggests that the Fc and C3b receptors are distinct entities.
Studies on gonococcus infection. XIV. Cell wall protein differences among color/opacity colony variants of Neisseria gonorrhoeae
Authors: Swanson J
Published: January 2020

Gonococci from colonies exhibiting optical opacity and dark coloration have surface proteins that are not visualized in isogenic transparent, light-colored colony forms. These "colony opacity-associated proteins" have apparent molecular weights varying from 24,000 to 30,000 by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate; their apparent molecular weights are independent of that for their major outer membrane protein. The opacity-associated proteins are more susceptible to hydrolysis by trypsin than is the major outer membrane protein, but gonococci possessing the opacity-associated protein(s) also show enhanced susceptibility of their major outer membrane proteins to the action of trypsin. These conclusions were reached by comparing the electrophoretic patterns of whole-cell lysates from both "laboratory strains" and several recent clinical isolates of Neisseria gonorrhoeae.
Plaque-forming cells in mice after experimental infection with Brucella abortus
Authors: Schneerson-Porat S , Feinhaken D , Pinto M
Published: January 2020

Cells producing antibody to brucella lipopolysaccharide were detected in spleens of mice infected with Brucella abortus 19 by a hemolytic plaque assay. The appearance of immunoglobulin M-producing cells preceded humoral antibodies. The primary plaques were observed 5 days after inoculation, and they were still present by day 70.
Isolation of specific and common antibodies to staphylococcal enterotoxins A and E by affinity chromatography
Authors: Lee A C , Robbins R N , Bergdoll M S
Published: January 2020

Specific and common antibodies to staphylococcal enterotoxins A and E (SEA and SEE) were isolated from anti-SEA and anti-SEE antisera by affinity chromatography. Anti-SEA and anti-SEE antisera were passed through a column with the cross-reacting enterotoxin coupled to a CNBr-activated Sepharose 4B matrix. Specifically bound common antibodies were eluted with NaSCN. The isolated specific antibodies reacted only with the homologous enterotoxin, whereas the common antibodies gave a reaction of identify with both enterotoxins in double gel diffusion plates. The common antibodies had a higher titer against SEE than against SEA. The significance of the isolation of antibodies common to two separate protein molecules is discussed.
Extraction of streptococcal type 12 M protein by cyanogen bromide
Authors: Vosti K L , Williams W K
Published: January 2020

Conditions for the release of streptococcal type 12 M protein from whole cells by cyanogen bromide are described; they demonstrated that methionine is not essential to the structural arrangements which account for some of its immunological and biological properties. The released M protein was separated from other proteins by column chromatography with hydroxylapatite. The type-specific molecules which reacted with precipitating antibodies were found only in the 0.3 M eluate, formed zones with mobilities less than 12% of that of the dye front on electrophoresis in the standard acrylamide disc gel system, formed at least four bands in sodium dodecyl sulfate-acrylamide disc gels with molecular weights ranging from 12,000 to 23,000, and stimulated the formation of opsonic antibodies in rabbits. Cyanogen bromide provides a highly specific method for the release of M proteins which should prove particularly useful in analyses of structural-functional relationships among different M proteins.
Effects of Ambient Temperatures on Induction of Transmissible Gastroenteritis in Feeder Pigs
Authors: Shimizu Mitsugu , Shimizu Y. , Kodama Y.
Published: January 2020

Experiments were carried out to investigate the effects of ambient temperatures on the induction of transmissible gastroenteritis in feeder pigs 2 to 3 months old. Pigs maintained at a high temperature (30 ± 2°C) and exposed to the virulent transmissible gastroenteritis virus did not show clinical signs of the disease during their maintenance at the high temperature. On the other hand, a sudden decrease in the ambient temperature, either before or after virus inoculation, induced severe disease in feeder pigs exposed to the virus. However, continuous maintenance of pigs at the low temperature (4 ± 1°C) tended to somewhat reduce the frequency of occurrence of signs in proportion to the length of the maintenance periods at that temperature. Pigs raised at temperatures that fluctuated between 20 ± 2 and 4 ± 1°C every 24 h developed profuse diarrhea. The duration of clinical signs was longer in pigs maintained under the fluctuating temperatures than in those at the constantly low temperature. With one exception, antibody against transmissible gastroenteritis virus was demonstrated in sera collected from pigs both with and without clinical signs. Antibody titers obtained, however, were somewhat higher in sera collected from pigs that had developed clinical signs than in those from pigs that had endured the infection without showing signs.
Polymorphonuclear cell function in the various polar types of leprosy and erythema nodosum leprosum
Authors: Sher R , Anderson R , Glover A , Wadee A A
Published: January 2020

Polymorphonuclear leukocyte motility, both in vivo and in vitro, and reduction of Nitro Blue Tetrazolium was studied in tuberculoid and lepromatous leprosy patients and a group of lepromatous patients with erythema nodosum leprosum (ENL). A profound defect in random migration, chemotaxis, and chemokinesis was found in lepromatous patients with and without complicating ENL, and marked depletion of skin window migration confirmed these in vitro findings. Tuberculoid patients exhibited a mild defect in polymorphonuclear leukocyte motility. Serum inhibitors of normal polymorphonuclear leukocyte chemotaxis were found in all types of leprosy, but sera from lepromatous and ENL patients were most inhibitory. Resting levels of Nitro Blue Tetrazolium reduction were normal in all three groups. Reconstitution of polymorphonuclear leukocyte cells from normal and ENL patients with ENL serum, however, showed increased Nitro Blue Tetrazolium reduction well above the normal range, whereas reconstitution with normal, lepromatous, and tuberculoid sera failed to increase Nitro Blue Tetrazolium reduction above the normal values.
Enzymatic degradation of H2O2 by Leptospira
Authors: Corin R E , Boggs E , Cox C D
Published: January 2020

The enzymes responsible for reducing H2O2 were surveyed in 49 strains of Leptospira by using semiquantitative assays for catalase and peroxidase. The survey revealed a differential distribution of catalase and peroxidase activities between the two leptospiral complexes. The pathogenic Leptospira interrogans strains gave strong catalase and weak or negative peroxidase reactions. Conversely, the nonpathogenic Leptospira biflexa strains gave strong peroxidase and negative or weak catalase reactions. An intermediate group of four L. biflexa strains, which were isolated from mammals, fell into the high peroxidase, low or negative catalase group. One water isolate, H-23, gave strong reactions for both enzymes and was examined for virulence and in vitro growth parameters. Results indicate metabolic differences between pathogens and water forms in their abilities to reduce H2O2.
Nonspecific and specific immunological mitogenicity by group A streptococcal pyrogenic exotoxins
Authors: Barsumian E L , Schlievert P M , Watson D W
Published: January 2020

Group A streptococcal pyrogenic exotoxin (SPE) types A, B, and C induced lymphocyte proliferation both specifically and nonspecifically, and the responses showed characteristics associated with both types of stimulation. Guinea pig lymphocytes from animals presensitized to SPE A displayed immunologically specific proliferation in response to SPE A; control lymphocytes showed little activity in the presence of SPE A. Lymphocytes from guinea pigs not presensitized to SPE responded nonspecifically to SPE types B and C. Guinea pig lymphocytes from SPE A-presensitized animals showed enhanced proliferation over controls when treated with SPE B, suggesting that a degree of cross-reactivity between SPE types may exist, though they are serologically distinct. Mouse splenic lymphocytes exhibited low-level responsiveness to all SPE types, as would be expected for an antigen-specific proliferative response. Unlike mouse splenic lymphocytes, rabbit spleen cells and human cord blood, lymphocytes responded nonspecifically to all SPE types. Although rabbit spleen cells and human cord blood lymphocytes responded nonspecifically, the maximum response occurred at day 4 or 5, comparable to an antigen-specific system rather than a day 2 or 3 such as that with the nonspecific thymus-derived cell mitogen, concanavalin A.
Genetics of Treponema: characterization of Treponema hyodysenteriae and its relationship to Treponema pallidum
Authors: Miao R M , Fieldsteel A H , Harris D L
Published: January 2020

Saturation reassociation assays with 125I-labeled treponemal DNAs show that Treponema hyodysenteriae is genetically unrelated to T. pallidum (Nichols), T. phagedenis biotype Reiter, and T. refringens biotype Noguchi. Pathogenic and nonpathogenic isolates of T. hyodysenteriae exhibited 28% sequence homology and had an extremely low guanine-plus-cytosine content (25.8%).
Requirement of calcium ions for cell degeneration with a toxin (vibriolysin) from Vibrio parahaemolyticus
Authors: Goshima K , Owaribe K , Yamanaka H , Yoshino S
Published: January 2020

A highly purified toxin (vibriolysin) from Vibrio parahaemolyticus caused degeneration of cell shape, such as bleb and balloon formation, of mouse myocardial cells and mouse melanoma cells in culture. An extracellular Ca2+ concentration of more than 10(-6) M was necessary for the degeneration of cell shape, but extracellular Mg2+, Na+, and K+ were not necessary. In the presence of extracellular Ca2+, vibriolysin also caused full contraction of myofibrils of mouse myocardial cells and reduction of both actin cables and tubulin networks of mouse melanoma cells. Vibriolysin also caused excess uptake of Ca2+ from the incubation medium by mouse myocardial cells and mouse melanoma cells. Chick myocardial cells, which show neither degeneration of cell shape nor full contraction of myofibrils, did not take up excess 45Ca2+ in the presence of vibriolysin. These findings suggest that the vibriolysin-induced degeneration of cell shape of mouse myocardial cells and mouse melanoma cells is due to excess uptake of Ca2+ from the incubation medium by the cells.
Isolation and characterization of a high-molecular-weight polysaccharide from the slime of Pseudomonas aeruginosa
Authors: Pier G B , Sidberry H F , Zolyomi S , Sadoff J C
Published: January 2020

A procedure is described for isolating a high-molecular-weight polysaccharide (PS) from the slime of Pseudomonas aeruginosa immunotype 1. The resultant material, obtained from the void volume of a Sephadex G-100 column, was composed of carbohydrate and water. No lipopolysaccharide (LPS), 2-keto-3-deoxyoctonoate, heptose, phosphate, or protein was detectable, and nucleic acid contamination was generally below 1%. The carbohydrate composition of the PS was glucose, rhamnose, galactose, arabinose, and mannose. PS had a molecular weight of between 100,000 and 350,000 and did not disaggregate when chromatographed in the presence of sodium deoxycholate. An antigen immunologically indistinguishable from PS could be obtained from LPS by either acetic acid hydrolysis and column chromatography or by allowing solutions of LPS to stand at room temperature for 3 days. Some of this LPS-associated polysaccharide eluted as the void volume of a G-100 column but differed from PS by its lack of galactose and arabinose. LPS also contained an immunodeterminant not shared with PS that was detected by its stability to dilute alkali treatment (0.1 N NaOH, 37 degrees C, 2 h). PS was destroyed by alkali treatment. PS appeared to represent a form of LPS polysaccharide side chain that contains galactose and arabinose and is of a high molecular weight.
Swiss and inbred mice in the infant mouse test for the assay of Escherichia coli thermostable enterotoxin
Authors: Pestana de Castro A F , Serafim M B , Rangel H A , Guerrant R L
Published: January 2020

Swiss and inbred mice (C3H, ASn, B10A, and C57) were used to assay different thermostable enterotoxins prepared from Escherichia coli strains 3 (human), E57 (swine), B41 (cattle), and S13 (sheep). All strains of mice detected enterotoxins, but some reacted better to a given thermostable enterotoxin preparation than other inbred strains. Since the results obtained with Swiss mice were more consistent than with inbred mice, the former are apparently more suitable in the infant mouse test.
Immunoglobulin-binding structure on bovine group G streptococci different from type III Fc receptors on human group G streptococci
Authors: Myhre E B , Holmberg O , Kronvall G
Published: January 2020

The immunoglobulin G (IgG)-binding capacity of 54 group G streptococci of human and bovine origin was investigated. Of 20 human strains, 17 carried a surface component which could combine with human IgG and bovine IgG1 and IgG2. Inhibition experiments with unlabeled human IgG and with a panel of animal sera revealed that the same surface component was involved in the binding of human as well as bovine immunoglobulins. Of 16 beta-hemolytic bovine group G streptococci, 13 reacted with human IgG but not with bovine IgG1 or IgG2. This binding structure was different from the type III Fc reactivity found in human group G streptococci. All human strains, including the three IgG Fc-nonreactive strains, fermented trehalose, in contrast to all bovine beta-hemolytic strains, which were negative. Immunoglobulin Fc reactivity is thus a feature not only of human strains but also of some bovine strains.
Cross-reaction between the mycelial galactomannas of three Hormodendrum strains and the mannans of two Candida albicans strains of different serotypes, A and B
Authors: Takeda N , Okubo Y , Ichikawa T , Suzuki S
Published: January 2020

Cross-reactivity between galactomannans of three representative Hormodendrum strains, H. pedrosoi IFO 6071, H. compactum IFO 6726, and H. dermatitidis IFO 6421, and the mannans of two Candida strains, C. albicans NIH A-207 (serotype A) and C. albicans NIH B-792 (serotype B), were investigated by means of agar-gel double diffusion, quantitative preciptin reaction, and passive cutaneous anaphylaxis. The following results were obtained. (i) Antisera to whole cells of three Hormodendrum strains were completely inactive in all in vitro antigen-antibody reactions to mannans of C. albicans NIH A-207 and C. albicans NIH B-792, whereas antisera to both C. albicans strains were found to be cross-reactive against the three Hormodendrum galactomannans. (ii) The results of cross-passive cutaneous anaphylaxis tests using guinea pigs sensitized with antiserum of three Hormodendrum and two Candida seemed to be consistent with those of the vitro assay. (iii) The reactivities of the corresponding acid-resistant core moieties of the three Hormodendrum galactomannas against two anti-C. albicans sera were nearly identical to those of the parent galactomannans in both in vitro and in vivo tests.
Clindamycin-associated enterocolitis in guinea pigs: evidence for a bacterial toxin
Authors: Knoop F C
Published: January 2020

Experimental enterocolitis was induced in guinea pigs by intraperitoneal injection of clindamycin. Specimens of feces were collected daily in phosphate-buffered saline (pH 7.0) and pooled every second day. The pooled samples were centrifuged to remove solids, and the supernatant was sterilized by membrane filtration. The sterile fecal supernatants were then dialyzed for 48 h against two 15-liter changes of phosphate-buffered saline and subsequently tested for toxicity in cultured monolayers of mouse adrenal cells. A filterable toxin(s) was found in the fecal supernatants on days 2, 4, and 6 postchallenge and not in pretreatment samples. The toxin(s) caused enterocolitis when administered orogastrically to healthy animals and altered the morphology of cultured mouse adrenal cells. The alteration of adrenal cell morphology was neutralized by specific antitoxin to Clostridium histolyticum.
Interactions between human granulocytes and Blastomyces dermatitidis
Authors: Sixbey J W , Fields B T , Sun C N , Clark R A , Nolan C M
Published: January 2020

We studied interactions in vitro between human granulocytes and the yeast-like form of Blastomyces dermatitidis, because granulocytes are prominent in the host response to systemic blastomycosis. In Boyden chamber assays, broth culture filtrates of B. dermatitidis contained levels of granulocyte chemotactic activity that were significantly higher than those present in similar culture filtrates of Histoplasma capsulatum and Cryptococcus neoformans, two fungi that characteristically do not elicit granulocytes in infected tissues. Microscopic study, including electron microscopy, demonstrated that granulocytes phagocytosed B. dermatitidis promptly and efficiently. Moreover, granulocytes emitted light (chemiluminescence) at a brisk rate during phagocytosis of B. dermatitidis, indicating activation of intracellular metabolic pathways. However, fungicidal assay showed that granulocytes (1:1 cell-yeast ratio, 10% serum) killed only 29% of the B. dermatitidis inoculum during 3 h of incubation. Taken together, these findings suggest that there is disparity between phagocytosis and intracellular killing of B. dermatitidis by human granulocytes, perhaps because of resistance of this fungus to granulocyte microbicidal mechanisms.
Effect of chronic Trypanosoma brucei infection on the course of louping ill virus infection in mice
Authors: Reid H W , Buxton D , Finlayson J , Holmes P H
Published: January 2020

The course of louping-ill virus infection in mice chronically infected with Trypanosoma brucei was investigated. The mean survival time of mice infected with virus alone was 10.2 days, compared to 12.8 days in mice infected with T. brucei 14 days before virus challenge, and the cumulative mortality in the two groups was 62.5 and 90%, respectively. Virus was only inconsistently detected in the blood of mice given virus alone but was regularly present at high titers for up to 12 days in the blood of mice previously infected with T. brucei. Titers of virus in brains were also higher in dually infected mice, and encephalitis was of greater severity. These results indicate that the immunosuppressive effect of chronic trypanosomiasis may markedly increase susceptibility to acute virus infection. In addition, it is concluded that vector-vertebrate relationships of arthropod-transmitted viruses may be altered by concurrent trypanosome infection.
Stability of the Resident Microflora and the Bacteriocinogeny of
Streptococcus mutans
as Factors Affecting its Establishment in Specific Pathogen-Free Rats
Authors: van der Hoeven J. S. , Rogers A. H.
Published: January 2020

The outcome of the experimental implantation of
Streptococcus mutans
strains in humans and animals is unpredictable, and neither success nor failure can be explained. It seems logical to assume that, apart from dietary and host factors, the characteristics of the
S. mutans
strain involved and those of the resident plaque microflora are important in colonization. For example, previous work in this laboratory suggested that bacteriocin production accounts at least in part for the establishment of an invading bacterium in a microbial ecosystem. In the present study, a complex specific pathogen-free Ny plaque ecosystem was obtained by the inoculation of specific pathogen-free rats with
Actinomyces viscosus
Ny1 and
S. sanguis
Ny101, and the establishment of
S. mutans
in such rats was then examined. It was found that bacteriocinogenic (
bac
+
) strains generally colonized in much higher proportions than non-bacteriocinogenic (
bac
−
) strains. Moreover, the longer the delay in introducing
S. mutans
, the poorer was its establishment. Shortly after inoculation of strains Ny1 and Ny101, there is probably a transient state in which microbial equilibrium has not been reached, but later the specific pathogen-free Ny system attains a stable climax community which more strongly resists invaders. The ability of a number of
S. mutans
strains to establish in such a climax community was then examined, and it was found that
bac
+
strains generally established at a higher level than did
bac
−
strains. In summary, it was concluded that, although the
bac
+
state is an important property in the successful invasion of a plaque by
S. mutans
, the stability of the resident microflora is also an important factor.
Tumor induction by Agrobacterium tumefaciens prevented in Vigna sinensis seedlings systemically infected by ribonucleic acid viruses
Authors: Saedi D , Bruening G , Kado C I , Dutra J C
Published: January 2020

Cowpea (Vigna sinensis) seedlings failed to develop tumors after being inoculated with crown gall bacteria (Agrobacterium tumefaciens) if, at times earlier than 1 day later, they were inoculated on the primary leaves with a cowpea mosaic virus that systemically infects them. Inoculation with buffer or with a virus that is restricted to a localized infection, or to which the cowpea is immune, did not interfere with the subsequent development of tumors. The virus infection did not appear to affect directly the titer of A. tumefaciens in the inoculation sites. Nor did mixing of virus particles with A. tumefaciens prevent subsequent appearance of tumors. The influence of virus infection extended across grafts (into tissue that is not susceptible to the virus) and there prevented tumor formation. The sap from infected plants, but not purified virus, decreased tumor formation on carrot disks. Systemic virus infection may induce in cowpeas a translocated substance that prevents tumor induction by A. tumefaciens.
Human cell-mediated immune responses to chlamydial antigens
Authors: Hanna L , Schmidt L , Sharp M , Stites D P , Jawetz E
Published: January 2020

A reproducible method was developed to determine the ability of chlamydial antigens to stimulate lymphocytes from volunteers. In tests repeated 4 to 14 times, the cells from a given volunteer gave a relatively narrow range of responses, but there were great differences in the mean response of different volunteers. In the entire group of 52 volunteers, lymphocyte stimulation was significantly associated with the presence of antibody, but in a given individual results of one test did not aid in predicting the results of the other. A majority of persons with either antichlamydial antibody or elevated lymphocyte stimulation, or both, did not have a history of signs or symptoms within a spectrum of chlamydial diseases. This may reflect the great frequency of asymptomatic infection with these organisms. The lymphocytes of some individuals were stimulated to a significantly greater degree by antigens of one chlamydial species (Chlamydia trachomatis or C. psittaci) than by the other. These and other cell-mediated reactions in human chlamydial infections, and their possible medical significance, are under continued study.
Effects of Zinc Chloride on Guinea Pig Complement Component Activity In Vitro: Concentration-Dependent Inhibition And Enhancement
Authors: Montgomery David W. , Chvapil Milos , Zukoski Charles F.
Published: January 2020

We have studied the in vitro effects of zinc chloride on the hemolytic activity of each component of the guinea pig classical complement pathway over a wide range (25 to 500 μM) of zinc concentrations. At high concentrations (>200 μM) the activity of all components was strongly inhibited by this metal. Concentrations of 500 μM inhibited C1 and C5 by 80 and 65%, respectively, whereas all other components were inhibited by more than 94%. Zinc chloride at 25 μM produced more varied effects, with C2, C3, and C6 inhibited by 36, 35, and 55%. C7 and C8 were inhibited by approximately 25%, whereas C1, C4, and C9 were not appreciably affected. The activity of the fifth component, on the other hand, was strongly enhanced by the presence of zinc. Concentrations of 25, 50, and 100 μM zinc chloride produced increases of 92, 44, and 18%, respectively, in C5 titers when present during the activation-binding step of this component. Further studies indicated that the activities of cell-bound complement components were unaffected by zinc treatment after activation and/or binding to the sheep erythrocyte surface had occurred. In addition, zinc did not appear to inhibit by causing irreversible denaturation of either total complement proteins or its various components. Rather, it appears that zinc must be present as a reactant during the activation and/or binding step of each component for inhibition or enhancement to occur.
Common antigens among systemic disease fungi analyzed by two-dimensional immunoelectrophoresis
Authors: Huppert M , Adler J P , Rice E H , Sun S H
Published: January 2020

The interpretation of immunological results in systemic mycoses has been complicated by cross-reactions among specimens from patients with blastomycosis, coccidioidomycosis, and histoplasmosis. The fungal preparations used in these tests evidently contained one or more antigens in common. Two-dimensional immunoelectrophoresis techniques were used to determine the number of antigens contained in several soluble extracts from Blastomyces dermatitidis and Histoplasma capsulatum that were common with those demonstrable in a coccidiodin-anticoccidioidin reference system. A total of 12 and 10 common antigens were found in preparations from B. dermatitidis and H. capsulatum, respectively. In addition, the crude preparations from each species of fungus exhibited some qualitative and quantitative differences in composition of antigens. Use of two-dimensional immunoelectrophoresis for standardization of fungus extracts, for monitoring separation of species-specific antigens, and for testing humoral antibody response should add further refinement to correlations with clinical disease.
Group and type antigens of Capnocytophaga
Authors: Stevens R H , Hammond B F , Lai C H
Published: January 2020

Group-specific and type-specific antigens have been identified and purified from sonic extracts of Capnocytophaga. The group-specific antigen, which was purified by affinity chromatography, was found to be identical to an antigen present in all 26 strains tested. The antigen is sensitive to trypsin, sodium dodecyl sulfate and heat labile, and composed predominantly (55%) of protein. The type-specific antigen, which was obtained by preparative immunoelectrophoresis, was found to be present in only 3 of the 26 strains tested. This antigen was resistant to heat, trypsin, and sodium dodecyl sulfate and was primarily composed of carbohydrate (47% phenol-sulfuric acid-positive material, 8% amino sugar). Agglutination and fluorescent antibody data suggest that both the group- and type-specific antigens reside on the cell surface.
Quantitative immunoelectrophoretic analysis of human antibodies against herpes simplex virus antigens
Authors: Vestergaard B F
Published: January 2020

By use of crossed immunoelectrophoresis with intermediate gel, antidbody titers against six individual herpes simplex virus (HSV) glycoproteins and two nonglycosylated proteins were determined in 100 human sera. High antibody titers were found against two different HSV type-common glycoproteins designated Ag8 and Ag11 (containing glycosylated polypeptides D and B, respectively). The anti-Ag8 and -Ag11 titers correlated with HSV neutralizing antibody titers. Most of the serological cross-reactivity between HSV type 1 and type 2 was probably caused by antibodies to Ag8 and Ag11. Human antibodies against one HSV type 1-specific glycoprotein (Ag6, containing glycosylated polypeptide C) and two HSV type 2 glycoproteins (Ag4 and Ag9) were also demonstrated, and the titers correlated better with neutralizing antibody titers of the homologous than of the heterologous virus type. The data presented can be directly applied to the further development of diagnostic reagents.
Effect of tobacco smoking on the functions of polymorphonuclear leukocytes
Authors: Corberand J , Nguyen F , Do A H , Dutau G , Laharrague P , Fontanilles A M , Gleizes B
Published: January 2020

Eight tests investigating the function of circulating polymorphonuclear leukocytes were performed in 68 subjects, half of whom smoked at least 20 cigarettes per day. Comparison of the two groups allowed determination of the in vivo effect of tobacco smoke on the nonspecific defense system of the body. Ingestion ability, oxygen consumption, and bactericidal activity were normal in smokers. Myeloperoxidase and neutrophil alkaline phosphatase activities also were unchanged. The nitroblue tetrazolium reduction and the serum lysozyme levels were slightly increased in smokers. The capillary tube random migration, though, was depressed, and intensive smoking further aggravated this change. It is suggested that tobacco smoke acts directly on one (or several) unidentified target site of polymorphonuclear leukocytes. This impairment, demonstrated in vivo, probably plays a role in the genesis of the bronchopulmonary diseases so frequent in heavy smokers.
Bactericidal activity of fractionated granule contents from human polymorphonuclear leukocytes
Authors: Modrzakowski M C , Cooney M H , Martin L E , Spitznagel J K
Published: January 2020

Proteins from human polymorphonuclear leukocyte granules were extracted with 0.2 M acetate, pH 4.0, and fractionated by Sephadex G-100 column chromatography. The fractions demonstrated selective bactericidal action against a deep rough cell wall mutant of Escherichia coli O111:B4 with rough lipopolysacharide and cell wall mutants of Salmonella typhimurium LT-2 with lipoplysacharide of Ra, Rc, Rd1, Rd2, and Re types. Smooth parent strains were most resistant to the bactericidal action. Fractions with greatest activity for the mutants were from valley regions (regions of low protein concentration) between three high protein peaks comprising myeloperoxidase, protease, and lysozyme, respectively. Susceptibility of the mutants to bactericidal action increased as sugar residues decreased in lipopolysaccharide. Gram-positive bacteria were susceptible to different fractions than were the gram-negative bacteria.
Hemagglutination and adhesiveness of toxigenic Escherichia coli isolated from humans
Authors: Thorne G M , Deneke C F , Gorbach S L
Published: January 2020

Toxigenic strains of Escherichia coli isolated from humans were studied for adherence to human buccal mucosal epithelial cells. The E. coli strains were labeled with 3H-amino acids or fluorescein isothiocyanate. Toxigenic E. coli strains varied in their ability to adhere in the presence of mannose. Of 32 toxigenic strains examined, 52% bound to the buccal cells, whereas none of 8 control strains did so (Mann-Whitney U test, P =0.007). The control strains were nontoxigenic E. coli isolates from humans, enterotoxigenic E. coli isolates from animals, and E. coli K-12 containing the K88 or K99 plasmid; these strains exhibited only background-level adherence in this assay. Among the toxigenic E. coli strains that bound to human buccal mucosal cells, there was no correlation with mannose-resistant hemagglutination (MR-HA) of guinea pig and human erythrocytes. Screening 32 strains, we found the following phenotypes: (i) MR-HA+, buccal adherent; (ii) MR-HA+, buccal nonadherent; (iii) MR-HA-, buccal adherent. Presumably the third group represents strains with another type(s) of surface attachment components not involved in the MR-HA reaction. Our findings indicate that a number of bacterial surface structures can function in MR-HA and buccal adherence.
Development of antibodies reactive in antibody-dependent cellular cytotoxicity in infectious mononucleosis
Authors: Hewetson J F , Böcker J F , Sereni P , Rapp C E , Henle W
Published: January 2020

Serial sera from patients with infectious mononucleosis were examined for the emergence of antibodies reactive in antibody-dependent cellular cytotoxicity tests, using Epstein-Barr virus-superinfected Raji cells as targets. For this specific purpose, the antibody-dependent cellular cytotoxicity test proved to be of limited sensitivity because only relatively high serum dilutions can be tested dependably, due to prozone effects at low serum concentrations, and because antibody-dependent cellular cytotoxicity reactions at the 5% level are not always statistically significant. Under the conditions of the test, antibody-dependent cellular cytotoxicity-reactive antibodies were not measurable, or only barely measurable, in early-acute-phase sera, but they became detectable during convalescence and increased thereafter, gradually over many months to the range of titers seen in healthy persons after long-past-primary Epstein-Barr virus infections. The percentages of antibody-dependent cellular cytotoxicity ultimately attained were on the order of 20% in most patients and healthy individuals, but in others did not exceed 10%. The likely identity of the antibodies reactive in the test with antibodies to late Epstein-Barr virus-determined cell membrane antigens has been discussed.
Effect of Type-Specific Active Immunization on the Development and Progression of Experimental
Pseudomonas aeruginosa
Endocarditis
Authors: Archer Gordon L. , Johnston J. Linda
Published: January 2020

Rabbits with intracardiac catheters were immunized with heat-killed
Pseudomonas aeruginosa
or saline and challenged with either 10
9
(high inoculum) or 10
7
(low inoculum) pseudomonas. Immunization did not decrease the incidence of endocarditis when compared with controls, but it did significantly prolong survival. The longer survival of immunized rabbits after high-inoculum challenge was not due to prolongation of the course of endocarditis but to type-specific protection from early, overwhelming bacteremia. However, after low-inoculum challenge there were no early deaths and there was a significantly (
P
< 0.01) longer survival of immunized (17.4 days) than unimmunized (10.6 days) animals dying of endocarditis. Increased survival was associated with higher total and 2-mercaptoethanol-resistant hemagglutinating antibody titers 1 week after challenge in immunized as compared with unimmunized rabbits. Early (48 h after challenge) vegetation colonization was also significantly (
P
< 0.05) greater after type-specific as opposed to non-type-specific or saline immunization and low-inoculum challenge. However, whereas 67% of type-specifically immunized rabbits had colonized vegetations at 48 h, only 38.9% died with bacteremic endocarditis. Another 19.2% of immunized rabbits had vegetations colonized with > 10
5
colony-forming units of pseudomonas at elective sacrifice 2 weeks after challenge but no bacteremia; no unimmunized rabbit exhibited similar late colonization. Preexisting antibody may be important in the pathogenesis of pseudomonas endocarditis in drug addicts, and its presence may explain the subacute and often protracted course of the disease.
Protease and elastase of Pseudomonas aeruginosa: inactivation of human plasma alpha 1-proteinase inhibitor
Authors: Morihara K , Tsuzuki H , Oda K
Published: January 2020

The present study indicates that crystalline elastase of Pseudomonas aeruginosa is a very potent inactivator of human plasma alpha 1-proteinase inhibitor, the enzyme (E) inactivated the inhibitor (I) almost completely within 1 h at 25 degrees C at a molar ratio of E/I = 1:100. The crystalline P. aeruginosa protease also inactivated the inhibitor, but 100-fold less. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis indicated that the alpha 1-proteinase inhibitor inactivated by the elastase and protease showed decreases in molecular weight of approximately 5,000 and 10,000, respectively. Regeneration of trypsin was negligible even when bovine trypsin-alpha 1-proteinase inhibitor complex (E/I = 1.0) was treated with the elastase. The affinity of alpha 1-proteinase inhibitor to trypsin was much higher than that to elastase. It was suggested that, assuming the pseudomonal proteases are produced and can inactivate alpha 1-proteinase inhibitor in vivo during pseudomonal diseases, the loss of alpha 1-proteinase inhibitor activity may permit the endogenous serine proteases to cause tissue destruction.
Strain differentiation of Neisseria gonorrhoeae by reverse passive hemagglutination
Authors: Armstrong A S , Mathias J R , DeYoung M I , Hirata A A
Published: January 2020

A reverse passive hemagglutination test that utilizes human erythrocytes coated with antibody to gonococci was developed to distinguish differences among 11 strains of Neisseria gonorrhoeae. Different rabbits were immunized with each strain of gonococcus. Antibody was purified by passing antiserum over an immunoadsorbent column containing homologous cell walls trapped in a cross-linked polyacrylamide gel. Antibody, after absorption with N. meningitidis, was used for coating 11 individual suspensions of erythrocytes, each with antibody to one gonococcal strain. The panel of coated erythrocytes was added to microtiter trays containing dilutions of homologous bacterial lysate and lysates from 10 heterologous strains. Agglutination titers were highest with homologous lysates, although cross-reactions occurred among some heterologous lysates. Lysates of nongonococcal Neisseria species and of other genera did not agglutinate coated erythrocytes. The reverse passive hemagglutination test can be a useful procedure to distinguish differences among strains of N. gonorrhoeae.
Assays for Endogenous and Exogenous Lymphoid Leukosis Viruses and Chick Helper Factor with RSV(−) Cell Lines
Authors: Crittenden L. B. , Eagen D. A. , Gulvas F. A.
Published: January 2020

Japanese quail cells transformed by the envelope-defective Bryan high-titer strain of Rous sarcoma virus [R(−)Q] were used as a source of the Rous sarcoma virus genome in three kinds of assays. (i) The simplest and most sensitive assay for infectious, endogenous viruses of the chicken belonging to subgroup E involved infection of a mixture of R(−)Q cells and turkey cells with the sample and assay of supernatants of these cells for focus formation on subgroup E susceptible cells. (ii) Inactivated Sendai virus-induced fusion of R(−)Q cells with live test cells was found to be a specific method for detection of chick helper factor. Focus formation by supernatant of the fused cells on subgroup E susceptible cells was correlated with the presence of subgroup E envelope glycoprotein on the plasma membranes of test cells. Whole blood cells as well as fibroblasts could be used in this assay. (iii) A method of assay for exogenous lymphoid leukosis viruses in which mixed cultures of R(−)Q cells and C/E cells and assay of supernatants for focus formation on C/E cells was as sensitive as assays presently used for exogenous lymphoid leukosis virus. Because no infectious Rous sarcoma virus was used as part of the procedure, the assays for infectious virus described here yielded pure pseudotypes of the input virus, an advantage for determining purity and subgroup of the input virus.
Immunotherapy of guinea pigs with dermal and visceral tumor implants: comparison of living and nonliving BCG
Authors: Yarkoni E , Peters L , Rapp H J , Hanna M G , Hunter J T
Published: January 2020

Emulsified cell walls of Mycobacterium bovis (BCG) were immunotherapeutically at least as active as living BCG in prolonging survival of guinea pigs with established dermal tumors and microscopic lymph node and visceral metastases.