bluuebunny/crossref_metadata_2025 huggingface dataset:
Antibody responses in humans to individual proteins of herpes simplex viruses
Authors: Gilman S C , Docherty J J , Rawls W E
Published: January 2020

Sera from 231 women were used to examine their frequency of precipitation of various herpes simplex virus type 1 and 2 (HSV-1 and HSV-2) proteins and to determine if there was a rank order of immune responsiveness of humans to these HSV antigens. Radiolabeled viral proteins were reacted with serum and immune complexes isolated with staphylococcal protein A. Individual antigens were resolved by polyacrylamide gel electrophoresis and visualized by fluorography. As a group, these sera precipitated 31 HSV-1 and 27 HSV-2 proteins. HSV-1 polypeptides with molecular weights of 133,000, 99,000, and 82,000, as well as HSV-2 polypeptides with molecular weights of 131,000 and 101,000, were precipitated by essentially all sera that contained antibodies to HSV-1 and HSV-2. When attempts were made to order the viral proteins by constructing precipitation profiles ranking the antigens in patterns according to their frequency of precipitation, it was observed that the antigens were generally not ordered. Demographic analysis of the sera suggested that the differences in the number of proteins precipitated were associated with differences in age, education, age at first marriage, and income, which collectively may reflect the frequency of exposure to the virus.
Glycolipid receptors for uropathogenic Escherichia coli on human erythrocytes and uroepithelial cells
Authors: Leffler H , Svanborg-Edén C
Published: January 2020

A specific family of glycolipids, the globoseries, was shown to act as receptors on human uroepithelial cells and erythrocytes for the majority of uropathogenic Escherichia coli strains attaching to or hemagglutinating those cells. This was demonstrated in three different ways: (i) correlation between the natural presence of glycolipid in the target cell (erythrocytes of different species) and binding of bacteria; (ii) inhibition of attachment to human uroepithelial cells by preincubation of bacteria and glycolipid; and (iii) induction of binding to unreactive cells by coating of these cells with glycolipid. Strains reacting with the receptor agglutinated guinea pig erythrocytes in a mannose-resistant way after, but not before, coating of the cells with globotetraosylceramide. Unrelated glycolipids were not recognized. The reaction was made independent of simultaneous occurrence of mannose-sensitive adhesions on the strains by addition of D-mannose. The receptor-coated cells were used as a tool to screen for prevalence of receptor recognition in a collection of 453 E. coli strains isolated from patients with urinary tract infection or from the stools of healthy children. Of 150 strains attaching to human uroepithelial cells and agglutinating human erythrocytes, 121 bound to globotetraosylceramide (81%). Globoside recognition was especially frequent among pyelonephritis strains (74/81). The glycolipid composition of the urogenital epithelium and kidney tissue and the ability of uropathogenic E. coli to bind to these glycolipids may be a determinant in host-parasite interaction leading to urinary tract infection.
Membrane-damaging and cytotoxic effects on human fibroblasts of alpha- and beta-hemolysins from Aeromonas hydrophila
Authors: Thelestam M , Ljungh A
Published: January 2020

The effects of two hemolysins (alpha and beta) from Aeromonas hydrophila on human lung fibroblasts were investigated. The toxins differed distinctly in regard to the morphological changes they produced. The alpha-hemolysin caused rounding of the cells. The beta-hemolysin caused a striking vacuolization of the cytoplasm in cells which remained spread out on the growth surface. The toxins also differed as to relative size of the initial lesions they induced in the fibroblast membrane, scored by leakage of different-sized cytoplasmic markers. The alpha-hemolysin induced larger lesions than did the beta-hemolysin. It was indirectly demonstrated that the alpha-hemolysin did not bind, or bound only transiently, to the fibroblasts. By contrast, the beta-hemolysin bound rapidly and firmly. The cytopathogenic response to the alpha-hemolysin was reversible, whereas cells treated with small amounts of the beta-hemolysin for only 1 min invariably died within a few hours. Thus, the two hemolysins from A. hydrophila, despite many biochemical similarities, show essential dissimilarities in their interactions with cultured cells.
Participation of pili and cell wall adhesion in the yeast agglutination activity of Escherichia coli
Authors: Eshdat Y , Speth V , Jann K
Published: January 2020

Escherichia coli strain 2699 (O6:K13) which had been isolated from a case of urinary tract infection exhibited pili during the stationary phase (24 to 40 h), but not during the exponential phase (4 h), when grown in static broth culture. The bacteria were also piliated when grown for 24 h on agar. They agglutinated Saccharomyces cerevisiae (baker's yeast) in the piliated as well as in the nonpiliated state. The agglutinations were mannose sensitive, i.e., they could be inhibited with 50 mM methyl-alpha-mannoside. The bacteria were first depiliated by shearing and then used for the isolation of outer membrane vesicles with an Omnimixer. Purified pili and outer membranes were characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and electron microscopy. The pili could be demonstrated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis only after treatment at low pH or in saturated guanidine hydrochloride which is typical of the common type 1 pili. Depiliated bacteria, purified pili, and purified outer membranes gave mannose-sensitive agglutination of S. cerevisiae. The findings are discussed with respect to possible mechanisms of cell agglutination.
Host Defenses in Experimental Scrub Typhus: Delayed-Type Hypersensitivity Responses of Inbred Mice
Authors: Jerrells Thomas R. , Osterman Joseph V.
Published: January 2020

Delayed-type hypersensitivity responses of inbred mice during the course of lethal and chronic infections with strains of
Rickettsia tsutsugamushi
were evaluated by using the influx of radiolabeled cells into antigen-injected ears. Congenic strains of C3H mice, which previously have been shown to be resistant (C3H/RV) or sensitive (C3H/HeDub) to lethal intraperitoneal infection with the Gilliam strain of rickettsiae, both expressed delayed-type hypersensitivity early in the course of infection (5 to 7 days). The sensitive C3H/HeDub mice, however, exhibited a marked decline in reactivity just before death. In contrast, reactivity of C3H/RV mice remained high through day 9 and declined slowly through day 15 after infection. Similar results were obtained when BALB/c mice were infected with either the Karp or the Gilliam strain of rickettsiae, which produce a lethal or nonlethal infection, respectively, in this strain of mice. Rechallenge of C3H/RV mice elicited a rapid increase in reactivity, suggesting a secondary memory response. To analyze delayed-type hypersensitivity during chronic infection, C3H/HeDub mice were immunized by subcutaneous infection with the Gilliam strain of
R. tsutsugamushi
, and both delayed-type hypersensitivity reactivity and resistance to intraperitoneal challenge were examined. Delayed-type hypersensitivity reactivity developed slowly and peaked at 21 days postimmunization, which correlated with resistance to intraperitoneal challenge. Delayed-type hypersensitivity reactivity declined thereafter, but resistance to intraperitoneal challenge remained through 28 days postimmunization. Delayed-type hypersensitivity reactivity increased after secondary challenge at 28 days, again suggesting antigen memory generated by primary immunization. Transfer of delayed-type hypersensitivity reactivity was accomplished by using immune thymus-derived splenic lymphocytes isolated with nylon-wool columns. Abrogation of the ability of immune spleen cells to transfer delayed-type hypersensitivity reactivity after treatment with anti-Thy 1.2 alloantiserum and complement further supported the view that delayed-type hypersensitivity responses to scrub typhus rickettsiae were mediated by thymus-derived lymphocytes.
Permissiveness of rabbit monocytes and macrophages for herpes simplex virus type 1
Authors: Plaeger-Marshall S , Wilson L A , Smith J W
Published: January 2020

The permissiveness of rabbit monocytes and macrophages for herpes simplex virus was examined. Peripheral blood monocytes, alveolar macrophages, and peritoneal exudate macrophages were studied for their ability to replicate herpes simplex virus strains RE and KOS. Results indicated different degrees of interaction with virus depending on the macrophage type. Only peritoneal exudate macrophages showed evidence of virus replication. Productive infection was limited, with only a small number of cells (0.02%) yielding infectious virus. Higher numbers of cells appeared to be abortively infected. Approximately 40% expressed antigens, whereas virtually all were killed by exposure to virus. Coreless particles were seen by electron microscopy in about one-third. Alveolar macrophages were also killed by virus and showed evidence of virus adsorption, but showed no indication of productive or abortive infection. Monocytes neither adsorbed nor replicated virus, and viability was unaffected. Results suggest that differences in degrees of cellular maturation or differentiation, or both, account for the spectrum of interactions seen between herpes simplex virus and rabbit macrophages.
Adherence of Haemophilus influenzae to buccal epithelial cells
Authors: Lampe R M , Mason E O , Kaplan S L , Umstead C L , Yow M D , Feigin R D
Published: January 2020

The role of adherence of Haemophilus influenzae to epithelial surfaces in the pathogenesis of infection is unknown. Fluorescent-antibody and radiolabeled adherence methods were adapted to study H. influenzae adherence to human buccal epithelial cells. By the fluorescent-antibody method, 19 of 21 (90%) nontypable H. influenzae strains were found to be adherent compared with 2 of 42 (5%) type b strains (P less than 0.0001). Using a radiolabeled adherence method, we found that 9 of 12 (75%) nontypable H. influenzae strains were adherent to buccal epithelial cells whereas only 3 of 32 (9%) type b strains were adherent (P = 0.001). Results of H. influenzae adherence examined by both methods correlated significantly (P = 0.01). H. influenzae adherence to adult pharyngeal, nasal, and buccal epithelial cells was comparable. Type b H. influenzae did not adhere to the buccal epithelial cells of well children, children with H. influenzae type b disease, or children with upper respiratory infections. In contrast, nontypable H. influenzae did adhere to the buccal epithelial cells of well children and children with upper respiratory infections. These observed in vitro differences in adherence between nontypable and type b H. influenzae strains may explain differences in colonization, pathogenesis, and types of infection due to nontypable and type b H. influenzae.
Comparison fo agglutinin titers for Streptococcus mutans in tears, saliva, and serum
Authors: Allansmith M R , Burns C A , Arnold R R
Published: January 2020

The agglutinin titers for three Streptococcus mutans serotypes (AHT, BHT, and 10449, representing serotypes a, b, and c, respectively) were measured in the saliva, tears, and serum of 19 human subjects. Naturally occurring S. mutans agglutinins were routinely present in all fluids tested in the absence of overt local stimulation by antigen. The immunoglobulin A nature of this secretory agglutinin activity was suggested by blocking with alpha heavy-chain-specific antiserum and by the demonstration of S. mutans-reactive immunoglobulin A in the saliva and tears by indirect immunofluorescence. This finding is consistent with stimulation and antigen commitment of immunoglobulin A precursor lymphocytes at remote sites and subsequent homing to the lacrimal system. The relationship of anti-AHT agglutinins to anti-10449 agglutinins differed among the body fluids tested. The tears had more agglutinins for strain AHT than for strain 10449, whereas the reverse was true for saliva and serum. A possible explanation is local antigen-driven expansion of AHT-reactive committed lymphocytes in the lacrimal tissues.
Dual role of the immune response in street rabiesvirus infection of mice
Authors: Smith J S , McCelland C L , Reid F L , Baer G M
Published: January 2020

The cellular and humoral immune responses of mice to footpad injection of salivary gland suspensions of street rabiesvirus were investigated. Suppression of these responses with cyclophosphamide both increased the overall mortality rate from (50 to 100%) and delayed onset of disease signs and death for 1 to 2 weeks. Despite the absence of disease signs in these immunosuppressed animals, virus was present in the central nervous system, as shown by fluorescent-antibody staining of corneal epithelium. The onset of paralysis after limited immunosuppression was temporally related to a return to immune responsiveness, and passive transfer of homologous immune serum to infected immunosuppressed animals brought about their early paralysis and death. These findings indicate the importance of the immune response in the pathogenesis of street rabiesvirus infection.
Evidence for mannose-mediated adherence of Candida albicans to human buccal cells in vitro
Authors: Sandin R L , Rogers A L , Patterson R J , Beneke E S
Published: January 2020

Various lectins and sugars were used to study the possible role of saccharide-containing moieties on the surface of Candida albicans and human buccal cells in the adherence of this yeast to mucosal surfaces. The lectins possessed affinities for several different sugar moieties and were used to pretreat C. albicans or buccal cells before mixing and incubating in the adherence assay. It was found that concanavalin A, a lectin that recognizes mannose and glucose, inhibited adherence of the pretreated yeasts to buccal cells and also inhibited adherence of pretreated buccal cells to nonpretreated yeast cells. Adherence was restored by preincubating the concanavalin A with a mannose derivative, but preincubation of concanavalin A with other sugars did not produce this effect. Lectins that do not recognize mannose had no effect on adherence. The presence of alpha-D-methyl mannopyranoside in the incubation medium during the assay inhibited adherence, whereas other sugars did not. Germinated yeasts adhered to buccal cells more effectively than nongerminated cells and were more susceptible to adherence inhibition by concanavalin A than were nongerminated yeasts. Thus, mannose-containing moieties on the surface of C. albicans and buccal cells could mediate the adherence of this yeast to human epithelium.
Characteristic differences between saliva-dependent aggregation and adhesion of streptococci
Authors: Rosan B , Malamud D , Appelbaum B , Golub E
Published: January 2020

Comparison of saliva-mediated aggregation of Streptococcus sanguis, Streptococcus mitis, and Streptococcus mutans and adhesion of these organisms to saliva-coated hydroxyapatite showed that there was no relationship between these two activities. Adsorption of salivary aggregating activity to bacteria appears to have little effect on the ability of the residual saliva to support adherence; conversely, adsorption of salivary adherence factors to hydroxyapatite does not affect aggregation. Although heating saliva significantly reduces bacterial aggregation, it has little or no effect on adherence. A comparison of aggregation and adhesion with serial dilutions of saliva demonstrated that adhesion could still be detected at 100 to 500-fold-lower concentrations of salivary protein that bacterial aggregation. These findings support the concept that aggregation and adherence involve two distinct mechanisms of microbial clearance in the oral cavity.
Complement consumption gonococcal peptidoglycan
Authors: Petersen B H , Rosenthal R S
Published: January 2020

Purified peptidoglycan (PG) obtained from Neisseria gonorrhoeae was tested for the ability to consume complement in normal human sera. Sonicated PG (S-PG), a heterogeneous mixture of soluble fragments (molecular weight, greater than 10(6)), as well as intact (insoluble) PG, reduced the level of whole hemolytic complement in a pool of four human sera. The minimal concentration of S-PG required for this activity was approximately 500 micrograms of S-PG per ml of serum. Complete lysozyme digestion of S-PG, yielding PG fragments of less than 10(4) molecular weight, eliminated complement-consuming activity. S-PG-mediated complement consumption resulted in depletion of the individual complement components C4 and C3. Consumption of complement did not occur when C4-deficient human serum or normal human sera treated with Mg2+-(ethylene glycol-bis(beta-aminoethyl ether)-N,N-tetraacetic acid to specifically impair classical complement pathway activity were used. The addition of rabbit anti-PG antibody greatly enhanced gonococcal PG-mediated complement consumption. Together, the data suggested that gonococcal PG-mediated complement consumption occurred via the classical complement pathway, was dependent on the presence of anti-PG antibody, and required glycosidically linked polymers of PG. Individual human sera varied widely in the extent of gonococcal PG-mediated reduction of complement levels, presumably a reflection of either different amounts of natural antibody to gonococcal PG, different levels of human PG hydrolase(s) capable of degrading PG to inactive fragments, or both.
Further studies on replication of virulent Treponema pallidum in tissue cultures of Sf1Ep cells
Authors: Fieldsteel A H , Cox D L , Moeckli R A
Published: January 2020

A number of parameters aimed at optimizing culture conditions for both Sf1Ep cells and Treponema pallidum have been investigated. Optimum temperature for replication of T. pallidum ranged between 33 and 35 degrees C. At 33 degrees C, replication occurred in the presence of atmospheric oxygen concentrations of less than 0.3 to 10%, the optimum range being 1.5 to 5%. No replication occurred in the presence of 12.5% oxygen. When both temperature and oxygen concentrations were varied between 33 and 35 degrees C and 1.5 to 5%, respectively, little differences in replication were noted. Although variation in the oxygen concentration within each temperature group had little or no effect on replication, it did have an effect on motility, which remained greater in the 5% oxygen concentration after 9 to 12 days of cultivation. Optimum concentration of fetal bovine serum in the culture medium was 20%, although replication occurred in concentrations ranging from 5 to 30%. If carefully screened, calf serum could be substituted for fetal bovine serum. Testis extract was an essential component of the culture medium. Although extract obtained from an adult rabbit--either normal or T. pallidum infected--was slightly superior, replication of T. pallidum occurred when rat or hamster testis extract was substituted.
Salmonella toxin synthesis is unrelated to the presence of temperate bacteriophages
Authors: Houston C W , Davis C P , Peterson J W
Published: January 2020

Several strains of Salmonella were examined for an association between the capacity to produce Salmonella toxin and the presence of bacteriophages. Based on the data obtained from this study, we concluded that genetic information responsible for Salmonella toxin synthesis was not inherited by lysogenic conversion.
Arthropathic Properties Related to the Molecular Weight of Peptidoglycan-Polysaccharide Polymers of Streptococcal Cell Walls
Authors: Fox Alvin , Brown Roger R. , Anderle Sonia K. , Chetty Chamroen , Cromartie William J. , Gooder Harry , Schwab John H.
Published: January 2020

The covalently bound polymers of peptidoglycan and group-specific polysaccharide (PG-APS) were isolated from the cell walls of group A streptococci. Arthritis was induced in rats with a single intraperitoneal injection of an aqueous suspension of PG-APS fragments derived by sonication. The joint lesions induced with this polydisperse suspension followed a bimodal pattern consisting of an acute phase, which reached a peak 5 days after injection and then receded, followed by a chronic, remittent, erosive arthritis lasting several months. The relative severities of the acute and chronic phases could be manipulated by selection of the size of PG-APS fragments. The fragments of PG-APS obtained by sonic treatment were resolved on the basis of size into three major populations by sucrose gradient or differential centrifugation. Based upon light scattering and gel filtration, the average molecular weight of the largest family of fragments was estimated to be about 500 × 10
6
, the intermediate fragments were 50 × 10
6
daltons, and the predominant size in the smallest population was 5.3 × 10
6
daltons. The larger fragments induced negligible acute inflammation, but chronic disease became apparent 5 to 9 weeks after injection. The smallest fragments induced the most severe acute inflammation, with relatively little late, chronic joint disease. The particles of intermediate size induced moderate acute inflammation and the most severe chronic, erosive joint lesions. A single injection of fragments of the isolated peptidoglycan moiety of the PG-APS induced only a moderate acute inflammation of joints, with no apparent capacity to maintain the injury and induce chronic disease.
Isolation and Characterization of Isogenic Pairs of Domed Hemolytic and Flat Nonhemolytic Colony Types of
Bordetella pertussis
Authors: Peppler Mark S.
Published: January 2020

Four different serotype strains of
Bordetella pertussis
, 3779BL
2
S
4
, Tohama I, 353/Z, and 2753, were plated on Bordet-Gengou agar, where they grew as domed, hemolytic (D
+
H
+
) wild-type colonies. Cloned D
+
H
+
colony types of all four strains were passed onto modified Stainer-Scholte medium solidified with 1% Noble Agar. Colonies were selected from Stainer-Scholte agar, and these subsequently grew as flat, nonhemolytic (D
−
H
−
) colonies when transferred back onto Bordet-Gengou agar. The frequency of D
−
H
−
organisms within a population of cloned D
+
H
+
was determined to be between 5 × 10
−5
and 5 × 10
−6
. The D
−
H
−
colony types maintained their flat, nonhemolytic characteristics for over 80 single-colony passages on Bordet-Gengou agar. The isogenic pairs of D
+
H
+
and D
−
H
−
colony types from the four strains were compared for hemagglutination titer, lymphocytosis-promoting activity, adenylate cyclase activity, and presence of agglutinogens by agglutination. In all cases the D
−
H
−
colony types showed reduced activities or amounts of antigen compared with their D
+
H
+
parents. Freely diffusible antigens were markedly different between the two phenotypes as noted by double diffusion of antisera added to plates on which colonies of the variants were growing. Antigens solubilized from the two colony types by Triton X-100 were also markedly different as judged by radial immunodiffusion with antifimbrial hemagglutinin, antilymphocytosis-promoting factor, and anti-353/Z adsorbed with autoclaved 353/Z. In addition, autoradiographs of
125
I-surface-labeled whole cells separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed unique banding patterns for each colony type. Since all organisms, regardless of colony type, were grown on Bordet-Gengou agar, the differences reported could not be due to medium composition. Differences between phenotypes were also independent of passage number on Bordet-Gengou agar. By analogy to previous studies, the D
−
H
−
organisms appear to fulfill the criteria for phase III or phase IV in the system of Leslie and Gardner (P. H. Leslie and A. D. Gardner, J. Hyg. 31:423-434, 1931) or phase III in the system of Kasuga et al. (T. Kasuga, Y. Nakase, K. Ukishima, and K. Takatsu, Kitasato Arch. Exp. Med. 26:121-134, 1954).
Virulence conversion of Legionella pneumophila serogroup 1 by passage in guinea pigs and embryonated eggs
Authors: Elliott J A , Johnson W
Published: January 2020

When virulent Legionella pneumophila is passaged on supplemented Mueller-Hinton agar, it remains virulent for guinea pigs and embryonated hen eggs for two passages. However, by the fifth passage the cultures become avirulent for guinea pigs. Flagella were not produced by L. pneumophila on the first passage on supplemented Mueller-Hinton agar. In contrast, 12 passages on charcoal-yeast extract agar did not result in the reduction of virulence or the loss of flagella of L. pneumophila. Growth in supplemented yeast extract broth or on Norit-A-filtered supplemented yeast extract agar also did not result in a reduction of the virulence of L. pneumophila. However, L. pneumophila did not produce flagella when grown on these two media. Thus, it appears that the production of flagella is not required for the virulence of L. pneumophila when administered by the intraperitoneal route of infection. A virulent flagellated form of L. pneumophila was recovered by passing an avirulent form six times in guinea pigs. When avirulent L. pneumophila was passaged 12 times in embryonated eggs, a nonflagellated form of the bacterium was recovered which had an increased virulence for guinea pigs and embryonated eggs. However, virulent forms were not recovered by passage of avirulent forms on commonly used laboratory media. These results support the suggestion that a suitable host is required for the selection of the virulent form of L. pneumophila from avirulent cultures.
Further purification and characterization of heat-stable enterotoxin produced by Yersinia enterocolitica
Authors: Okamoto K , Inoue T , Shimizu K , Hara S , Miyama A
Published: January 2020

Heat-stable enterotoxin (ST) of Yersinia enterocolitica was produced under defined conditions. It was first detected in the culture supernatant of the late-logarithmic phase of growth and increased lineally during the the stationary phase of growth. The ST level became maximum at the decline phase of growth, and the ST was not detected in the lysate of bacteria obtained from the decline phase of growth. The ST was extensively purified from the culture supernatant, and about a 1,905-fold purification was achieved with a yield of 8.9%. The minimal effective dose of the purified ST was approximately 25 ng in the suckling mouse assay. The purified ST gave a single 280-nm absorbing peak on polyacrylamide disc gel electrophoresis and had a maximum absorption at 272 nm, and its molecular weight was 9,700 by Sephadex G-75 superfine gel filtration. The biological activity of the purified ST was lost by treatment with 2-mercaptoethanol, suggesting that the ST contained disulfide bridges in the molecule which were required for the development of toxic activity. The purified ST was heat stable at 100 degrees C for 10 min between pH 2.2 and 8.0, but not at pH values greater than 9.0 or in 2 N HCl. The treatment of the ST with trypsin resulted in a retarded elution of the ST activity by Sephadex F-75 superfine gel filtration and a passage through a UM-20 membrane filter.
Production of mononuclear cell chemotactic factors during Sindbis virus infection of mice
Authors: Mokhtarian F , Griffin D E , Hirsch R L
Published: January 2020

Draining lymph node cells of mice infected subcutaneously with Sindbis virus (SV) produced two mononuclear chemotactic factors in vitro. One factor did not require the addition of SV in vitro and was only detectable during the first week after infection. A second factor, resembling lymphocyte-derived chemotactic factor, required the addition of SV in vitro, was first detectable at 3 days, reached a peak at 15 to 18 days, and was gone by 29 days after infection. The production of this factor was virus specific. Diluent-inoculated mice produced no detectable mononuclear chemotactic factors in response to SV. In vitro production of the virus-specific chemotactic factor was dependent on both adherent cells and sensitized Lyt1+ T cells. In vitro production of the spontaneous factor was associated only with adherent cells but also appeared to be T cell dependent, since the lymph node cells from SV-infected athymic nude mice failed to produce either factor. Infectious center assays showed that adherent cells contained infectious SV without replicating it, suggesting the engulfment of virus by macrophages in the lymph node draining the area of virus replication. These cells probably process virus as antigen for presentation to T cells, resulting in local production of chemotactic factors as well as production in more distant sites of viral replication after leaving the lymph node. These virus-stimulated, mononuclear cell-produced chemotactic factors are likely to be of importance in generating the mononuclear inflammatory response.
Expression of a high-affinity mechanism for acquisition of transferrin iron by Neisseria meningitidis
Authors: Simonson C , Brener D , DeVoe I W
Published: January 2020

Iron-starved meningococci grown at either pH 7.2 or 6.6 were capable of removing and incorporating iron from human transferrin by a saturable, cell surface mechanism that specifically recognized transferrin rather than iron. The maximum expression of the iron uptake system occurred after 4 h of iron starvation. The uptake of the iron was dependent upon a functioning electron transport chain and was sensitive to 60 degrees C and trypsin. Cells grown under iron-sufficient conditions were incapable of accumulating iron from transferrin. No evidence was found for a primary role for cell-free soluble siderophores in the removal of iron from transferrin. The nonpathogenic neisseriae, Neisseria flava and N. sicca, were unable to utilize iron on transferrin.
Protection of mice from infection with Streptococcus pneumoniae by anti-phosphocholine antibody
Authors: Yother J , Forman C , Gray B M , Briles D E
Published: January 2020

Anti-phosphocholine (PC) antibody mediated protection against many strains of Streptococcus pneumoniae, and hybridoma anti-PC antibodies protected mice from fatal infections with types 1 and 3 S. pneumoniae. Live types 1, 3, 5, 6A, and 19F S. pneumoniae had similar amounts of surface PC accessible to antibody. Furthermore, mice expressing the X-linked immunodeficiency (xid) of the CBA/N strain were found to be more susceptible to infection with S. pneumoniae of types 3, 6A, and 19F than were immunologically normal mice. The only exception to these results was with the type 5 strain, which was highly virulent for both xid and normal mice. In addition, we were unable to protect mice against infection with the type 5 strain by using anti-PC antibody.
Role of granulocytes in experimental Streptococcus sanguis endocarditis
Authors: Meddens M J , Thompson J , Eulderink F , Bauer W C , Mattie H , van Furth R
Published: January 2020

We investigated the role of granulocytes during the induction and course of experimental Streptococcus sanguis endocarditis in rabbits by depleting blood granulocytes with nitrogen mustard. The induction of the endocarditis was not influenced by granulocytopenia: the 50% infectious dose was 5.4 X 10(4) colony-forming units in normal and granulocytopenic rabbits. However, granulocytopenia influenced the curse of the endocarditis, as shown by a significant increase in the number of colony-forming units per gram of vegetation (P less than 0.02) from 24 to 72 h after the injection of 10(5) colony-forming units of S. sanguis. This rise did not occur in the control rabbits. Furthermore, bacteremia was significantly higher in the granulocytopenic rabbits (P less than 0.05) during the first 48 h compared with the control rabbits. This was not because of altered clearance of the streptococcus inoculum or seeding of streptococci from extracardiac bacterial foci. We concluded that granulocytes have no measurable effect on the induction of S. sanguis endocarditis, but during the course of the endocarditis, granulocytes keep the endocardial infection in check.
Enzymatic Modification of Bacterial Receptors on Saliva-Treated Hydroxyapatite Surfaces
Authors: Gibbons R. J. , Etherden I.
Published: January 2020

Certain properties of experimental pellicles formed by the adsorption of salivary components on hydroxyapatite surfaces change over time. To determine whether enzymes likely to be present in the oral environment could induce such changes, pellicles were treated with saliva which had been incubated for 18 h at 35°C to promote the elaboration of microbial enzymes. This treatment markedly reduced the numbers of
Streptococcus mutans
MT3 and JBP and
S. sanguis
FC-1 and C5 cells which attached, but it had little or no effect on the attachment of
S. mitis
RE7,
Actinomyces viscosus
LY7 and CK-8,
Bacteroides gingivalis
381, or
B. melaninogenicus
subsp.
intermedius
581. Heating the incubated saliva at 60°C for 30 min partially reduced its pellicle-modifying activity, whereas heating at 80°C for 30 min or 100°C for 15 min completely eliminated such activity. This indicated that the saliva contained heat-labile substances, presumably enzymes, which could affect the pellicle receptors involved in the attachment of
S. mutans
and
S. sanguis.
Treatment of saliva-treated hydroxyapatite with commercially obtained enzyme preparations also affected bacterial attachment. Thus, treatment with galactose oxidase reduced the numbers of the
S. mutans
strains which attached, whereas treatment with neuraminidase reduced the adsorption of
S. sanguis
FC-1 but not that of
S. sanguis
C5. Treatment with β-glucosidase preparations derived from almonds significantly reduced the attachment of all of the streptococcal strains studied, but, when subjected to isoelectric fractionation, the adherence-inhibiting activity did not correlate directly with β-glucosidase activity. Treatment of the pellicles with trypsin or eight other glycosidases did not affect streptococcal attachment. Exposure of the enzymatically modified pellicles to fresh saliva did not restore the streptococcal receptors. Collectively, the data suggest that some bacterial receptors in the pellicle coating of teeth can be modified by enzymes likely to be present in the oral environment, and these interactions may affect oral bacterial ecology.
Only the chemotactic subpopulation of human blood monocytes expresses receptors for the chemotactic peptide N-formylmethionyl-leucyl-phenylalanine
Authors: Falk W , Harvath L , Leonard E J
Published: January 2020

Human peripheral blood monocytes comprise a subpopulation of 20 to 40% that is capable of responding to chemoattractants and a remaining subpopulation that cannot respond. We were able to obtain 99%-pure attractant-responsive monocytes by using a newly constructed separation chamber. The binding of the radioactive chemotactic peptide N-formylmethionyl-leucyl-[3H]phenylalanine to migrating and nonmigrating populations was then studied. The binding was saturable at room temperature in the presence of azide. Saturation occurred at 5 x 10(-8) M, and 50% of the maximal binding was obtained at 10(-8) M, the concentration that induced optimal chemotaxis. The nonmigrating monocytes did not bind the peptide under the same conditions, which shows that at least one reason for a nonresponsiveness to chemotaxin is apparently a lack of receptors. By Scatchard analysis we calculated an equilibrium dissociation constant ranging from 23 to 37 nM; the number of binding sites per cell ranged from 64,000 to 77,000. The binding was very rapid. Fifty percent of the optimal binding occurred at 3.5 min, and equilibrium was reached after 20 to 30 min. Chemotactic deactivation of the monocytes reduced the number of available binding sites by 60%.
Effect of Escherichia coli alpha-hemolysin on human peripheral leukocyte viability in vitro
Authors: Cavalieri S J , Snyder I S
Published: January 2020

To gain further evidence that Escherichia coli alpha-hemolysin has a role in pathogenesis, its effect on human peripheral leukocyte viability was studied in vitro. Viability of leukocytes exposed to low doses of alpha-hemolysin decreased nearly 10-fold within 15 min of exposure. This response was dose and time dependent and was neutralized by antiserum, heat, proteases, and lipase. To gain further evidence that alpha-hemolysin was the molecule responsible for leukotoxicity, preparations of alpha-hemolysin were passed through a hydrophobic interaction chromatographic column. Alpha-hemolysin prepared in this way retained its leukotoxic activity. Both hemolytic and leukotoxic activities copurified at the same ratio and were inactivated to the same degree by heating at 56 degrees C. Lysis of leukocytes, if it occurs in vivo, would enhance the chances of survival for an invading hemolytic E. coli.
Immunoglobulin M and G antibody response to type- and subtype-specific antigens after primary and secondary exposures of mice to influenza A viruses
Authors: Gonchoroff N J , Kendal A P , Phillips D J , Reimer C B
Published: January 2020

A mouse model of influenza infection was studied to help define parameters that may affect serodiagnosis of human infections by immunoassays. Antibodies to both type- and subtype-specific influenza A antigens were measured by a solid-phase immunofluorometric assay. Dilute mouse sera were added to purified influenza virus that had been covalently bound to polyaminostyrene microbeads, and the bound antibody was detected by fluorescein isothiocyanate-labeled isotype-specific antisera. Results were consistent in that upon exposure of mice by either infection alone or by vaccination after infection, both immunoglobulin M (IgM) and IgG antibodies reactive with newly encountered subtype specific viral antigens were measured. IgG antibody was usually detectable by the solid-phase immunofluorometric assay several days before it could be detected by a hemagglutination inhibition test. Increased levels of antibody of the IgG1, IgGa, IgG2b, and IgG3 subclasses were also measured during influenza infection. Surprisingly, response to type-specific viral antigens was of the IgG class in primary as well as in secondary exposure. The results suggest that for serodiagnosis of influenza infections by detection of specific IgM antibody, the assay should use subtype-specific antigens.
Effect of Immune Serum or Polymyxin B on
Escherichia coli
-Induced Inflammation and Vascular Injury
Authors: Issekutz Andrew C. , Bhimji Shabir , Bortolussi Robert
Published: January 2020

Bacterial invasion of the tissues often stimulates a vigorous inflammatory reaction, which may limit the spread of microorganisms but may also be accompanied by serious vascular injury and tissue damage. We previously studied the inflammatory reaction induced by the injection of killed
Escherichia coli
into rabbit skin, a model suitable for the quantitation of various parameters of inflammation. Here we report the effect of immune serum treatment of the
E. coli
on their capacity to induce inflammation and vascular injury. Injection of killed
E. coli
treated with immune serum elicited a reaction which had a smaller increase in vascular permeability (protein exudation), measured with
125
I-labeled albumin, less increase in blood flow, measured with
86
RbCl, less leukocyte infiltration, measured with
51
Cr-labeled leukocytes, and a lesser degree of hemorrhage, measured with
59
Fe-labeled erythrocytes, than
E. coli
treated with nonimmune serum. Crossover experiments with four different
E. coli
serotypes and four different antisera indicated that antibody to specific O antigens or a related antigen, but not to K or H antigen, was important for modifying the inflammatory response. Treatment of four different
E. coli
serotypes with antiserum to “core” glycolipid, produced by immunization with the
E. coli
J5 mutant, inhibited the inflammatory response to all four
E. coli
serotypes. Finally, treatment of killed
E. coli
with polymyxin B also inhibited their inflammation-inducing potential. These results suggest that it may be possible to diminish the magnitude of local vascular and tissue injury associated with
E. coli
infections by the use of antisera or polymyxin B, which bind to endotoxin on the
E. coli.
Generation of cytolytic T-cell cultures displaying measles virus specificity and human histocompatibility leukocyte antigen restriction
Authors: Sethi K K , Stroehmann I , Brandis H
Published: January 2020

In the present study, peripheral blood lymphocytes from eight randomly selected, healthy, measles virus-seropositive donors were used to initiate and expand T-cell cultures during secondary immune response in vitro. Five of the donors yielded continuously growing T-cell cultures which showed reproducible strong lytic activities towards measles virus-infected autologous fibroblasts. Uninfected or herpes simplex virus-infected targets were weakly susceptible to these effectors. By contrast, T-cell cultures from three other seropositive donors expressed comparable lytic activities for measles virus- or herpes simplex virus-infected targets, but not for uninfected autologous targets. The five T-cell cytolytic cultures which revealed measles virus specificity also displayed human histocompatibility leukocyte antigen (HLA)-A and HLA-B restriction, i.e, were lytic for targets sharing HLA-A or HLA-B or both with them. Additionally, it was found that a monoclonal anti-HLA antibody (W6/32) could effectively block the measles virus-specific and HLA-A- and HLA-B-related lytic activities of these cytotoxic T-lymphocytes. The specificity of this blocking effect was reflected by the inefficacy of a monoclonal anti-HLA-DR antibody to block the cytotoxic T-lymphocyte-mediated lysis.
Morphological examination of the glycocalyces of Staphylococcus aureus strains Wiley and Smith
Authors: Caputy G G , Costerton J W
Published: January 2020

The glycocalyces of gram-positive bacteria have only been studied to a limited extent, with most studies being directed at the elucidation of capsules. With modern methods of electron microscopy, it has been shown that an extensive, diffuse polyanionic matrix surrounds Staphylococcus aureus cells of the Smith and Wiley strains, both in vivo and in modified staphylococcus 110 media. This slime layer was extracapsular in the case of the Smith strain, yet appeared to be the only layer peripheral to the teichoic acid in the Wiley strain. It is proposed that these glycocalyces serve a protective function and that their production is induced not only by excess nutrients in the growth medium but also by metabolic stress.
Conditions required for induction of interferon by rotaviruses and for their sensitivity to its action
Authors: McKimm-Breschkin J L , Holmes I H
Published: January 2020

Our investigations of interferon induction by rotaviruses showed that only when cells were pretreated with interferon, i.e., primed, could infectious rotaviruses induce significant quantities of interferon. As little as 0.5 U of interferon provided sufficient priming for this induction. UV-irradiated rotaviruses induced significant levels of interferon, and priming only marginally enhanced the yields. Neither heat-inactivated virus nor serum-neutralized virus was able to induce interferon, even when cells were primed. When cells were treated with purified virus double-stranded RNA in the presence of DEAE-dextran to facilitate uptake, interferon was induced, although priming did not enhance yields. These results strongly implicate the viral double-stranded RNA as the effector for interferon induction. The insensitivity of rotaviruses to interferon in vitro was also studied. Results suggested that this lack of sensitivity was not due to any inherent resistance of the virus to the antiviral proteins, but rather to lack of activation of cellular enzymes exhibiting antiviral activity.
Iron-suppressible production of hydroxamate by Escherichia coli isolates
Authors: Stuart S J , Greenwood K T , Luke R K
Published: January 2020

A total of 476 strains of Escherichia coli isolated from humans, pigs, cattle, poultry, potable water, or effluent were examined for iron-suppressible ability to produce hydroxamate. Isolates able to produce such material (Hyd+ isolates) are presumed to be able to carry out hydroxamate-dependent transport of iron. The percentages of Hyd+ isolates found among E. coli isolated from the feces of breast-fed babies (71%), adults (46%), milk-fed calves (32%), or poultry (28%) were significantly greater (P less than 0.01) than the percentages isolated from potable water and effluent (6%) or from the feces of suckling piglets (6%), weaned pigs (6%), or weaned cattle (4%). The percentages of Hyd+ isolates found among E. coli associated with diarrhea in humans (51%), weaned pigs (7%) or calves (25%) were not significantly different (P greater than 0.1) from those found among strains isolated from corresponding nondiarrheic hosts. Many of the E. coli isolated from cases of E. coli bacteremia in humans and poultry were Hyd+ (64% and 83%, respectively). We conclude that ability to carry out hydroxamate-mediated transport of iron is widely distributed among natural isolates of E. coli but that the distribution of Hyd+ E. coli is not random. E. coli isolated from sources where levels of available iron might be expected to be low tend to be Hyd+. It seems that a link may exist between prevalence of Hyd+ E. coli and active host-defense based on restricted availability of iron.
Induction of alpha and beta interferons during the hyporeactive state of gamma interferon by Mycobacterium bovis BCG cell wall fraction in Mycobacterium bovis BCG-sensitized mice
Authors: Nakane A , Minagawa T
Published: January 2020

Characterization of interferon (IFN) induced by a second challenge with specific antigen was investigated during the development of hyporeactivity established after challenge of Mycobacterium bovis BCG-sensitized mice with BCG cell wall fraction (BCG-CW). When BCG-sensitized mice were challenged with BCG-CW, IFN-gamma was detected in the circulation 4 h later and rapidly disappeared. After IFN-gamma disappeared from their blood, mice became completely hyporeactive to the second challenge with BCG-CW for 1 day, and thereafter they recovered from this hyporeactive state. However, we always observed that IFN induced at first by the second challenge with BCG-CW during the hyporeactive state was type I IFN-alpha/beta, but thereafter was entirely IFN-gamma. Induction of IFN-alpha/beta by the specific antigen during restoration from the hyporeactive state in BCG-sensitized mice is discussed.
Serum and urogenital antibody responses to Escherichia coli pili in cystitis
Authors: Rene P , Dinolfo M , Silverblatt F J
Published: January 2020

Antipili antibody (APA) was quantitated by enzyme-linked immunosorbent assay in the serum, urine, and vaginal secretions of 12 women with cystitis due to Escherichia coli. Pili were purified from the strain infecting each patient. The geometric mean titers of APA in serum taken at the initial visit were: immunoglobulin G (IgG), 23.7 +/- 3.9; IgA, 4.1 +/- 4.0; and IgM, 4.4 +/- 5.7. No consistent change was observed between samples obtained at 3 and 6 weeks. APA in serum from 10 control patients was assayed against a pool of pili assembled from the 12 infecting isolates. The geometric mean titers of the control sera were: IgG, 8.4 +/- 3.2; IgA, 9.6 +/- 2.4; and IgM, 0. Antipili IgG and IgM were significantly greater in the infected than in the control sera (P less than 0.05). APA was not detected in the urine or vaginal secretions from any infected or control patient. Antigenic relationships between the 12 infecting strains were investigated by indirect immune electron microscopy. All but 1 of 12 infecting strains shared antigenic determinants. Two patients had a second E. coli infection during the study. The pili of the reinfecting isolates showed partial antigenic cross-reactivity with the pili of the initial infecting bacteria. These observations indicate that although cystitis stimulates the development of serum APAs, it fails to stimulate local APA and thus may not engender any immunological barrier to subsequent recolonization.