bluuebunny/crossref_metadata_2025 huggingface dataset:
Type-specific antibodies to structurally defined fragments of streptococcal M proteins in patients with acute rheumatic fever
Authors: Bisno A L , Berrios X , Quesney F , Monroe D M , Dale J B , Beachey E H
Published: January 2020

Group A streptococci of M protein type 5 have been epidemiologically related to acute rheumatic fever in a number of reported outbreaks. Preliminary bacteriological evidence suggests that M5 may be an important "rheumatogenic" type in Santiago, Chile. To assess further the relationship of this streptococcal serotype to rheumatic fever in Chile, sera of 34 patients with rheumatic fever and an equal number of age-, sex-, and race-matched controls were assayed for antibodies to types 5, 6, and 24 in an enzyme-linked immunosorbent assay with purified pepsin extracts of the respective M proteins as solid-phase antigens. Sera of 11 rheumatic fever patients (32%) were positive (titer greater than 1:800) for type 5 antibodies, but only 1 (3%) of the matched controls was positive (P less than 0.01). Neither the patients nor the controls had antibodies to type 24. Although 38% of the patient sera contained antibodies to type 6, 29% of the control sera also had such antibodies (P greater than 0.20). The enzyme-linked immunosorbent assay served as an accurate predictor of which sera contained type 5 opsonic antibodies as measured by the opsonophagocytic test. Although antigenic cross-reactivity exists between M protein type 5 and type 6 group A streptococci, this phenomenon is unlikely to have accounted for the preferential occurrence of type 5 antibodies in rheumatic fever sera. The enzyme-linked immunosorbent assay and opsonic antibody results suggest that M5 is an important rheumatogenic type in Chile.
Role of macrophages in the lymphocyte response to Actinomyces viscosus
Authors: McCarron R M , Fitzgerald J E , Birdsell D C
Published: January 2020

Macrophage cooperation has been considered necessary for lymphocytes to express a variety of their differentiated functions. We attempted to characterize macrophage-lymphocyte cooperation in response to a known periodontal pathogen. Actinomyces viscosus T14V. Using adherent murine cells and subpopulations of splenocyte cultures, we assessed the effect of A. viscosus T14V fractions on lymphocyte proliferation. We determined that (i) various fractions of A. viscosus induced different proliferative responses; (ii) the physical state of the A. viscosus component determined the degree of dependence on adherent cells for proliferation; (iii) the proliferative response to supernatants of sonicated A. viscosus involved interaction among adherent cells and T and B cells; and (iv) the effects of adherent cells on the proliferative response were due to cell-to-cell interactions.
Capacity of influenza virus-monoclonal antibody mixtures to stimulate memory and cytotoxic T lymphocyte populations
Authors: Greenspan N , Hurwitz J L , Doherty P C
Published: January 2020

The magnitude of the cytotoxic T lymphocyte response in both immunologically naive mice and in mice primed with a serologically non-cross-reactive influenza A virus was greatly diminished if the virus used for challenge was first incubated with excess hemagglutinin-specific monoclonal antibody. However, the level of T cell stimulation was, when compared with virus stocks that are simply diluted, greater than would be expected from the infectivity titer remaining after exposure to the monoclonal antibody. Also, mice given mixtures of virus and monoclonal antibody were primed for a secondary cytotoxic T lymphocyte response, the frequency of memory T cells being approximately fourfold lower than that found for animals injected with virus alone. The possibility that such virus-antibody mixtures might be of value for immunization is worth further investigation.
Pathogenesis of rotavirus infection in mice
Authors: Little L M , Shadduck J A
Published: January 2020

Three parameters of rotavirus infection, i.e., clinical disease, viral antigen in infected intestines, and infectious virus in feces, were assessed in infant mice nursed by mothers with or without preexisting rotavirus antibody. Diarrhea was the only consistent sign of clinical disease, and its course followed that of infection by about 1 day. Infected intestinal epithelial cells, except crypt cells, were observed by immunofluorescence microscopy in the duodenum, jejunum, ileum, and colon. Infection progressed in a proximal-to-distal direction with time. Viral antigen appeared in intestinal tissue later, was present in lower amounts, and disappeared sooner from infants nursed by mothers with preexisting rotavirus antibody, indicating that protection was passively transferred to these infants although the course of clinical disease was not changed.
Effects of immunosuppression with cyclophosphamide on acute murine cytomegalovirus infection and virus-augmented natural killer cell activity
Authors: Selgrade M K , Daniels M J , Hu P C , Miller F J , Graham J A
Published: January 2020

The effects of cyclophosphamide (CY) treatment on acute murine cytomegalovirus (MCMV) infection were studied to explore the potential usefulness of MCMV as a means of detecting immune dysfunction and to identify host defense mechanisms important for protection against MCMV. Conditions found optimal for enhancing MCMV infection with CY included infecting adult mice with 2 X 10(5) PFU or more of virus and administering 80 mg or more of CY per kg 1 to 3 days later. In addition to enhanced mortality, virus titers in lung, liver, and spleen were elevated in CY-treated mice, and wet weights of liver, spleen, and thymus were depressed when compared with those of infected but untreated mice. Treatment with CY before MCMV challenge was not as efficient a means of enhancing mortality as treatment after virus challenge. The effect that the time of CY administration relative to infection had on mortality correlated with the effect of such timing on natural killer cell activity. Animals treated before infection exhibited depressed natural killer cell activity initially. However, they rapidly recovered this response, and by 5 days postinfection they had the same level of virus-augmented activity seen in untreated mice. In contrast, animals treated after infection did not recover natural killer cell activity and were more likely to die. A similar correlation was not obtained when the effects of CY on lymphocyte responses to B and T cell mitogens were examined, nor were there striking differences in pathology between the treatment groups. The data suggest an important role for natural killer cells in host defense against MCMV. Also, increased susceptibility to MCMV may provide a useful indicator of deficits in the natural killer cell response.
Effect of neonatal thymectomy on dental caries in rats
Authors: Ebersole J L , Taubman M A , Smith D J
Published: January 2020

The effect of T-cell depletion on susceptibility to dental caries after infection with Streptococcus mutans was studied. Rats were neonatally thymectomized (Tx) and infected with S. mutans 6715 or locally immunized with the homologous organism before infection. The Tx rats uniformly exhibited a higher level of infection with S. mutans and subsequently showed a greater extent of carious activity. Correlation studies were performed comparing the level of salivary and serum anti-S. mutans antibodies and the relative amount of dental caries. The results demonstrated that salivary immunoglobulin A antibody after immunization and infection, or infection only, showed a significant negative correlation with dental caries. Also, after local immunization, serum immunoglobulin G antibody showed a negative correlation with dental caries in the rats. These findings further support a major protective role for salivary immunoglobulin A in experimental dental caries in rats.
Bacteriolysis of Streptococcus mutans GS5 by lysozyme, proteases, and sodium thiocyanate
Authors: Wilkens T J , Goodman H , MacKay B J , Iacono V J , Pollock J J
Published: January 2020

Streptococcus mutans GS5 was grown in a synthetic medium containing radioactive thymidine to monitor cell lysis by assay of the release of DNA. Bacteriolysis was achieved by sequential treatment of the cells with either hen egg white lysozyme and sodium thiocyanate or a combination of hen egg white lysozyme and a proteolytic enzyme followed by addition of the thiocyanate. In the absence of sodium thiocyanate, a small percentage of the total macromolecular thymidine was released in control reaction mixtures during incubation. This amount of released DNA more than doubled in trypsin-treated cells, but the inclusion of lysozyme in reaction mixtures prevented assay of the DNA. Lysis was found to be optimal in the late log phase of growth and was dependent on the concentrations of both lysozyme and protease. Concentrations of trypsin or chymotrypsin as low as 0.01 microgram/ml were found to be effective in enhancing the lytic process. The addition of protease to lysozyme-inorganic salt reaction mixtures altered both the pH and ionic strength profiles of cell lysis. At pHs of 5.5 or lower, both the lysozyme-NaSCN and the lysozyme-trypsin-NaSCN systems were inactive in mediating lysis. The loss of insoluble cell wall peptidoglycan by lysozyme treatment was pH independent and did not appear to be affected by the addition of protease. Either diluted whole saliva or neutrophil extracts could replace trypsin to enhance cell lysis further.
Increased thymocyte-activating factor in human gingival fluid during gingival inflammation
Authors: Charon J A , Luger T A , Mergenhagen S E , Oppenheim J J
Published: January 2020

In this study, human gingival fluid from normal subjects was shown to contain a low-molecular-weight factor (molecular weight, 10,000 to 25,000) which augmented murine thymocyte proliferation, enhanced the production of interleukin 2 by T lymphocytes, and augmented the proliferation of fibroblasts. These biochemical and biological properties are characteristic of both macrophage-derived interleukin 1 and epidermal cell-derived thymocyte-activating factor. In addition, we have established that epidermal thymocyte-activating factor or interleukin 1 or both are present to a greater extent in gingival fluid obtained from sites manifesting gingival inflammation. In fact, thymocyte-activating activities were found to be greater in gingival fluid from inflamed than from noninflamed gingival sites from the same subjects. These findings suggest that human gingival fluid contains epidermal thymocyte-activating factor or interleukin 1 or both, which may amplify the inflammatory response in periodontal tissues.
Murine cellular cytotoxicity to syngeneic and xenogeneic herpes simplex virus-infected cells
Authors: Kohl S , Drath D B , Loo L S
Published: January 2020

Cellular cytotoxicity of C57BL/6 adult mice peritoneal cells to xenogeneic (Chang liver) and syngeneic (BL/6-WT3) herpes simplex virus (HSV)-infected cells was analyzed in a 6-h 51Cr release assay. There was no difference in antibody-dependent cellular cytotoxicity to either target. There was no natural killer cytotoxicity to targets with cells from uninfected mice except at very high effector cell ratios. HSV-infected (2 X 10(4) PFU intraperitoneally 1 day previously) mice mediated significantly higher antibody-dependent cellular cytotoxicity and required less antibody (10(-5) versus 10(-2) dilution), fewer cells, and less time to kill than cells from uninfected mice. HSV-infected mice mediated natural killer cytotoxicity but preferentially killed syngeneic HSV-infected cells. Stimulation of cytotoxicity was not virus specific since influenza-infected mice mediated similar levels of cytotoxicity to HSV-infected targets. There was no difference in morphology (95% macrophage) or in the percentage of FcR-positive cells, but infected mice had more peritoneal cells and generated higher levels of superoxide in response to opsonized zymosan or phorbolmyristate acetate. These data demonstrate nonspecific virus-stimulated metabolic and effector cell function which may enhance clearance of virus in an infected host.
Effect of alphavirus infection on mouse embryos
Authors: Atkins G J , Carter J , Sheahan B J
Published: January 2020

Seven strains and mutants of the alphaviruses, Semliki Forest virus and Sindbis virus, differed in their lethality for mouse embryos and their mothers. The A7 strain and the neurovirulence mutant M103 of Semliki Forest virus were selected for detailed comparison. A7 produced 100% lethality of mouse embryos but was avirulent for their mothers. M103 did not kill embryos or their mothers but did induce postnatal immunity. This immunity could be induced in utero or by suckling to an immune mother. Infectious virus could be recovered from the brain, blood, and embryos of mice infected with A7. Mice infected with M103 developed a viremia of similar titer, but virus could not be recovered from brain or embryos. Electron microscopy showed multiplying virus in trophoblast and fetal tissue after infection with A7, but no virus could be detected in such tissue after infection with M103. Cultures of ectoplacental cone trophoblast cells incubated in the presence of A7 or M103 showed multiplying A7 in the giant cells, but no M103. It is concluded that A7 can traverse both the blood-brain barrier and the placenta, whereas M103 can traverse neither.
Effect of a glucosyltransferase inhibitor on glucan synthesis and cellular adherence of Streptococcus mutans
Authors: Koga T , Hamada S , Murakawa S , Endo A
Published: January 2020

The effects of mutastein, a glucosyltransferase inhibitor derived from an Aspergillus terreus strain, on the glucan synthesis by glucosyltransferases of Streptococcus mutans and sucrose-dependent adherence of S. mutans cells were examined in vitro. The synthesis of insoluble glucan by crude glucosyltransferase of S. mutans strain B13 was markedly inhibited by mutastein at a final concentration of 10 micrograms of protein/ml. The synthesis of insoluble glucan adherent to glass surfaces was almost completely inhibited by mutastein at this concentration. In addition, mutastein inhibited the sucrose-dependent adherence to glass surfaces of resting and growing cells of various S. mutans strains. These results suggest that mutastein could be useful for controlling dental plaque and dental caries in vivo.
Human neutrophil chemotactic response to group A streptococci: bacteria-mediated interference with complement-derived chemotactic factors
Authors: Wexler D E , Nelson R D , Cleary P P
Published: January 2020

The influence of M protein on the capacity of group A streptococci to generate neutrophil chemotactic activity in normal human serum was examined. Incubation of serum with M- bacteria for up to 10 min led to the production of chemotactic activity. In contrast, incubation of serum with M+ bacteria did not elicit serum chemotactic activity over a 1-h period, even though complement was activated to completion. Further experiments revealed that both M+ and M- bacteria could inhibit the chemotactic activity of serum preexposed to zymosan. However, the M+ bacteria possessed a 130-fold-greater inhibitory capacity in this regard than the M- bacteria. This antichemotactic property was not detectable in the fluid phase of serum incubated with bacteria, thereby ruling out neutrophil-directed effects. Treatment of the bacteria with trypsin resulted in the release of the inhibitory molecule, suggesting that proteins are involved in its maintenance at the cell surface. However, the resistance of the chemotactic factor inactivator to pepsin and trypsin indicated that the protease-sensitive M protein was not involved. These results demonstrate a heretofore uncharacterized activity of group A streptococci that may contribute to virulence through modulation of the host chemotactic response.
T-lymphocyte subpopulations in relation to immunosuppression in measles and varicella
Authors: Arneborn P , Biberfeld G
Published: January 2020

Patients with measles or varicella were studied during the acute phase (first week) of illness and, after recovery, by lymphocyte stimulation tests and determination of T-lymphocyte subpopulations, using the monoclonal antibodies Leu 2a and Leu 3a directed at the suppressor/cytotoxic and the helper T-cell subsets, respectively. Low proliferative responses to phytohemagglutinin were found during the acute phase of both diseases. The response to purified protein derivate of tuberculin was also low in all measles patients tested and in some of the varicella patients. In both infections increased spontaneous DNA synthesis was demonstrated. In the acute phase of measles there was T lymphocytopenia but no change of the ratio between T lymphocytes of helper and suppressor/cytotoxic cell phenotypes. In the acute phase of varicella the percentage and the absolute number of Leu 2-positive (suppressor/cytotoxic) T cells were increased. Measurement of the size of the lymphocytes indicated activation of this subset. Cryopreserved blood mononuclear cells from the acute phase of varicella could suppress the phytohemagglutinin response of autologous convalescent-phase cells. This was not seen when cells from measles patients were tested. The suppression of the lymphocyte stimulation response in varicella is probably in part caused by activation of suppressor cells, whereas the suppression of the stimulation response in measles seems to be due mainly to other mechanisms.
Effect of interferon on the growth of Chlamydia trachomatis in mouse fibroblasts (L cells)
Authors: Rothermel C D , Byrne G I , Havell E A
Published: January 2020

The effect of murine interferon on the growth of the lymphogranuloma venereum biotype of Chlamydia trachomatis (strain 440L) in murine fibroblasts (L cells) was examined. Treatment of infected cell cultures with interferon caused a reduction in the number of inclusion-bearing cells as seen by light and electron microscopy and a decrease in yields of chlamydiae as determined by infectivity assays. Interferon also inhibited cycloheximide-resistant (chlamydia-specific) protein synthesis in infected cells. The interferon effect was dose dependent, with 80 to 90% inhibition occurring at concentrations of greater than 200 IU/ml. The inhibitory effect was neutralized by anti-murine interferon globulin. Interferon did not inactivate extracellular chlamydiae, and both host cell RNA and protein synthesis were required for the development of the interferon-induced antichlamydial state. Inhibition of chlamydial growth by interferon was demonstrable in cells treated 18 h before infection or up to 4 h after infection. Cells infected after interferon was removed exhibited an antichlamydial activity decline which was complete by 30 h after interferon removal. We show that interferon treatment did not affect either entry of chlamydiae into host cells or chlamydial conversion to reticulate bodies but rather caused a reduction in the rate of reticulate body replication.
Effect of Oxygen-Dependent Antimicrobial Systems on
Legionella pneumophila
Authors: Lochner Janis E. , Friedman Richard L. , Bigley Robert H. , Iglewski Barbara H.
Published: January 2020

Legionella pneumophila
was susceptible to the antimicrobial action of oxygen metabolites generated by both the myeloperoxidase-H
2
O
2
-halide and the xanthine oxidase systems.
Analysis of Human Rotavirus Mixed Electropherotypes
Authors: Spencer Eugenio G. , Avendaño Luis F. , García Bernardo I.
Published: January 2020

Mixed human rotavirus electropherotypes were detected in stool samples from patients with acute gastroenteritis in Santiago, Chile. These electropherotypes accounted for 10% of 149 samples studied. The finding of extra RNA fragments with respect to the regular 11 genome segments suggests the possibility of simultaneous or sequential infection by more than one electropherotype in a single diarrhea event or occurrence of modification in the length of the RNA segments during an infection. These possibilities arose from gel electrophoretic analysis of unique and sequential samples of human rotavirus genome RNA.
Enteropathogenic
Escherichia coli
Serotypes and Endemic Diarrhea in Infants
Authors: Toledo M. Regina F. , Alvariza M. do Carmo B. , Murahovschi Jayme , Ramos Sonia R. T. S. , Trabulsi Luiz R.
Published: January 2020

Enteropathogenic
Escherichia coli
serotypes were searched for in feces of 550 children with endemic diarrhea and in 129 controls, in São Paulo, in 1978 and 1979; serotypes O111ab:H
−
, O111ab:H
2
, and O119:H6 were significantly associated with diarrhea in children 0 to 5 months old and were the most frequent agents of diarrhea in this age group as compared with enterotoxigenic and enteroinvasive
E. coli, Salmonella
sp.,
Shigella
sp., and
Yersinia enterocolitica.
It is concluded that various enteropathogenic
E. coli
serotypes may be agents of endemic infantile diarrhea.
Role of myeloperoxidase in luminol-dependent chemiluminescence of polymorphonuclear leukocytes
Authors: Dahlgren C , Stendahl O
Published: January 2020

When polymorphonuclear leukocytes (PMNL) and soluble or particulate matter interact, the cells produce chemiluminescence, linked to activation of the oxidative metabolism of the cells. PMNL isolated from a patient with a myeloperoxidase deficiency were found to produce almost no luminol-dependent chemiluminescence, despite a pronounced production of superoxide anions (O2-). The chemotactic peptide formylmethionyl-leucyl-phenylalanine induced a two-peak chemiluminescence response in control PMNL. The response was modified, both in magnitude and in time-course, when the cells were incubated at 22 degrees C for 120 min. Addition of purified myeloperoxidase to the PMNL lacking this enzyme, before stimulus addition, resulted in a chemiluminescence response. In the response to formylmethionyl-leucyl-phenylalanine, only one peak, corresponding to the initial peak of control PMNL, was found. This indicated that luminol-dependent chemiluminescence is dependent on and directly related to the presence of myeloperoxidase in PMNL and that both intra- and extracellularly located myeloperoxidase has to be taken into account when interpreting the cellular response assayed as chemiluminescence.
Immunochemical Properties of Glucosyltransferases from
Streptococcus mutans
Authors: Fukui Kazuhiro , Kokeguchi Susumu , Kato Keijiro , Miyake Yoichiro , Nogami Ryuzo , Moriyama Takafumi
Published: January 2020

Antiserum against purified mutansynthetase (EC 2.4.1.?) of
Streptococcus mutans
6715 (serotype
g
), which is responsible for the synthesis of water-insoluble glucan (ISG) in the presence of both sucrose and water-soluble glucan, was prepared. The specificity of the antiserum was tested by using crude enzyme preparations (CEPs) of
S. mutans
strains of various serotypes. On immunodiffusion, the antiserum cross-reacted with CEPs from strains of serotypes
a
(HS-6 and AHT),
d
(OMZ176), and
g
(OMZ65 and KIR), but not with those from strains of serotypes
b
(BHT and FA-1) and
c
(GS-5 and Ingbritt). The antiserum inhibited the synthesis of ISG by crude or purified mutansynthetase of
S. mutans
6715. The activities of ISG synthesis by CEPs from the strains antigenically related in the foregoing immunodiffusion were inhibited by the antiserum against strain 6715 mutansynthetase. The antiserum, however, also inhibited the enzyme activity of the strains of serotype
b.
The finding that the antiserum against purified dextransucrase of
S. mutans
HS-6 inhibited ISG synthesis by a CEP of strain HS-6 and also by CEPs of antigenically related strains suggested that dextransucrase activity is involved in ISG synthesis.
Induction of nonspecific tolerance to endotoxins reduces the alveolar bone resorption in ligature-treated rats
Authors: Nowotny A , Sanavi F
Published: January 2020

Previous experimental data from various laboratories indicate that endotoxin of gram-negative oral microorganisms might be one of the most important bacterial products involved in bone resorption during periodontitis. Immunologically nonspecific tolerance to endotoxins in rats was induced by repeated application of Serratia marcescens trichloroacetic acid-extracted endotoxin. Silk ligature was placed on the second maxillary molar of the endotoxin-tolerant rats as well as of control rats in which tolerance to endotoxin had not been induced. The animals were sacrificed 8 days later. The rats showed no specific immune response to the tolerance-inducing endotoxin as measured by passive hemagglutination and by the lymphoblast assays, but we found that bone resorption was significantly reduced in the endotoxin-tolerant rats as compared with ligature-treated animals in which tolerance to endotoxin had not been induced.
Virus-Specific Immunity in Neonatal and Adult Mouse Rotavirus Infection
Authors: Sheridan J. F. , Eydelloth R. S. , Vonderfecht S. L. , Aurelian L.
Published: January 2020

Mouse rotavirus (epizootic diarrhea of infant mice) was used as a model to study the role of virus-specific immunity in infection and diarrheal disease. The distribution of viral antigen in intestinal tissues was determined by immunofluorescent staining with anti-simian rotavirus (SA-11) serum. The location and proportion of antigen-positive cells appeared to vary as a function of time postinfection and age of the animal at the time of infection. In animals infected at 1 and 7 days of age, antigen-positive cells (5 to 25%) were first detected (1 day postinfection) in the proximal segment of the small intestine, and infection progressed to the middle and distal segments. At 10 days postinfection, virus-infected cells were no longer observed in the proximal segment. In animals infected at 21 days of age (disease-free), a significantly lower proportion of cells were antigen positive (2 to 5%), and they were restricted to the middle and distal segments of the small intestine. Infection, defined according to the presence of virus and viral antigens in intestinal tissues and by seroconversion in the immunoglobulin M (IgM) isotype as determined by enzyme-linked immunosorbent assay with SA-11 antigen, was observed for all age groups (neonatal to adult), even in the presence of virus-specific serum or intestinal immunoglobulins. On the other hand, diarrheal disease was not detected in neonatal mice (1 to 3 days old) positive for passively acquired virus-specific intestinal IgG. The presence of virus-specific IgA in the intestinal tract at the time of infection did not protect from subsequent diarrheal disease. Virus-specific, cell-mediated immunity, determined by a delayed-type hypersensitivity response, did not develop in neonatal mice infected at 5 and 12 days of age. Reinfection of adult mice was associated with suppression of virus-specific delayed-type hypersensitivity and a significant decrease in the titers of the virus-specific serum IgG and IgA.
Isolation and characterization of a bacteriophage factor that confers competence for genetic transformation to an exfoliative toxin-producing strain of Staphylococcus aureus
Authors: Jackson M P , DeSena J , Lednicky J , McPherson B , Haile R , Garrison R G , Rogolsky M
Published: January 2020

Competence for genetic transformation in an exfoliative toxin-producing strain of Staphylococcus aureus was shown to be dependent on a virion factor that was isolated from a crude bacteriophage 80 alpha lysate. This competence-conferring factor was completely separated from infectious virus particles after either centrifugation through a neutral sucrose velocity gradient or fractionation on a Sepharose 2B gel. Since the competence-conferring factor tends to aggregate, optimal separation was obtained after treatment of the phage factor with the detergent Nonidet P-40. The competence-conferring factor had a molecular weight between 3 X 10(6) and 20 X 10(6) and an approximate sedimentation coefficient of 252. The factor was neutralized after interaction with antiserum prepared against isolated infectious 80 alpha virions. Electron microscopy of transforming cells that were exposed to isolated competence-conferring factor revealed a significant number of abnormally long and aggregated phage tail-like structures attached to the surface of recipient cells. This phenomenon was only observed in the presence of donor DNA, indicating that a phage tail-DNA-surface receptor complex might be one of the early steps in DNA-mediated transformation of S. aureus.
Effect of Delayed-Type Hypersensitivity Reaction and Transferred Lymphokine on the Resistance of Mice to
Salmonella typhimurium
Infection
Authors: Fukazawa Yoshimura , Kagaya Keiko , Ishibashi Yoshio
Published: January 2020

Immune mice which exhibited a delayed-type hypersensitivity reaction to bovine serum albumin after bovine serum albumin immunization and stimulation and normal mice that had been transferred with a lymphokine-rich fraction from the supernatant of concanavalin A-stimulated spleen cell cultures demonstrated resistance to
Salmonella
infection.
Effects of two metabolites of ochratoxin A, (4R)-4-hydroxyochratoxin A and ochratoxin alpha, on immune response in mice
Authors: Creppy E E , Størmer F C , Röschenthaler R , Dirheimer G
Published: January 2020

The metabolites of ochratoxin A, (4R)-4-hydroxyochratoxin A and ochratoxin alpha, were investigated for immunosuppressive properties in BALB/c mice. The standard plaque-counting technique for the estimation of antibody-producing spleen lymphocytes was used. (4R)-4-hydroxyochratoxin A was found to be an immunosuppressor almost as highly effective as ochratoxin A. Doses of 1 microgram of (4R)-4-hydroxyochratoxin A per kg administered to mice caused an 80% reduction in the number of cells producing immunoglobulin M (90% with ochratoxin A) and a 93% reduction in cells synthesizing immunoglobulin G (92% with ochratoxin A). Ochratoxin alpha, however, was ineffective. A possible mode of action is discussed.
Effect of growth phase and cell envelope structure on susceptibility of Salmonella typhimurium to the lactoperoxidase-thiocyanate-hydrogen peroxide system
Authors: Purdy M A , Tenovuo J , Pruitt K M , White W E
Published: January 2020

The lactoperoxidase-thiocyanate-hydrogen peroxide system was found to have both bacteriostatic and bactericidal activities against strains of Salmonella typhimurium. The bactericidal activity was clearly dependent on the permeability of the bacterial cell envelope. The deep rough mutant TA1535, with the most permeable cell envelope, was killed both at neutral and acid pH, whereas very little or no killing was observed with the intact cells of the parent strain hisG46. The delta gal mutant, TA1530, representing an intermediate in cell envelope permeability, was inhibited to a much lesser extent than TA1535. Bacteria in log phase of growth were more sensitive to the bactericidal effects than were those in stationary phase. Growth phase had little influence on the bacteriostatic effects. The hisG46 strain produced significant quantities of acid in the presence of glucose. This acid production was inhibited by the lactoperoxidase-thiocyanate-hydrogen peroxide system, and, in contrast to results obtained with several strains of streptococci, this inhibition was not reversed by addition of a reducing agent (2-mercaptoethanol).
Differential effect of immunoglobulin on the in vitro growth of several isolates of Plasmodium falciparum
Authors: Brown G V , Anders R F , Knowles G
Published: January 2020

Immunoglobulin isolated from the sera of individuals living in a malarious area of Papua New Guinea was tested for an effect on the growth in vitro of four isolates of Plasmodium falciparum, three from Papua New Guinea and one from Thailand. The Papua New Guinea isolates were inhibited to the same degree by individual immunoglobulin preparations, and inhibition varied from 0 to 98% (assessed by a radioisotopic readout). Immunoglobulin preparations which inhibited the Papua New Guinea isolates caused less inhibition of the Thai parasites. Biosynthetically labeled parasite proteins were analyzed by two-dimensional gel electrophoresis, and differences were detected in the protein and antigenic composition of isolates which differed in their sensitivity to inhibitory immunoglobulin. Three acidic proteins (Mr 200,000, 150,000, and 65,000) were found only in the Papua New Guinea isolates. All Papua New Guinea isolates contained a high-molecular-weight basic protein with an Mr of 220,000 (Pf220), but the corresponding protein of the same molecular weight in the Thai isolate had a more acidic isoelectric point. Another isolate (from Africa) initially showed a degree of resistance to inhibition by Papua New Guinea immunoglobulin (although not to the same extent as the Thai parasite), but in later experiments, this isolate was susceptible to inhibition. During the course of this series of experiments, the antigenic composition of this (uncloned) isolate changed so that it became similar (but not identical) to the Papua New Guinea isolates.
Enhancement of Pseudomonas aeruginosa lung clearance after local immunization with a temperature-sensitive mutant
Authors: Sordelli D O , Cerquetti M C , Hooke A M , Bellanti J A
Published: January 2020

We investigated the capacity of the temperature-sensitive mutant strain A/10/25 of Pseudomonas aeruginosa (ts-Psa) to induce enhancement of lung defenses against wild type P. aeruginosa (wt-Psa). Mice of the DBA/2J inbred strain were immunized by aerosolization with a single dose of 2 x 10(5) to 4 x 10(5) CFU of ts-Psa and were challenged 7, 14, and 21 days later with wt-Psa. The uncleared bacteria ratio was determined 4 h after aerosol exposure; significant enhancement in lung clearance of wt-Psa (P less than 0.01) was evident as early as 7 days after immunization and detectable for at least 21 days. Aerosol immunization with Staphylococcus aureus did not enhance lung clearance of wt-Psa; however, slight but significant enhancement in S. aureus clearance was observed in mice immunized 7 days before with ts-Psa. No enhancement of S. aureus clearance was seen in ts-Psa immunized animals after 14 and 21 days. Analysis of the cell composition of lung lavage fluids revealed a transient cell response characterized by rapid increase in the absolute number of polymorphonuclear leukocytes, followed later by an increase in alveolar macrophages. The characteristics of lung lavages returned to base-line values 6 days after aerosol immunization, and a second exposure to a ts-Psa aerosol produced a response of similar magnitude and quality. We conclude that aerosol immunization with a temperature-sensitive mutant of P. aeruginosa enhances specific pulmonary defense mechanisms against the parental pathogen in mice.
Effect of adsorbed protein on hydroxyapatite zeta potential and Streptococcus mutans adherence
Authors: Reynolds E C , Wong A
Published: January 2020

The adherence of Streptococcus mutans PK1 to hydroxyapatite disks pretreated with various acidic and basic proteins in imidazole buffer was studied. Adsorption of a basic protein onto an hydroxyapatite disk enhanced or had no effect on bacterial adherence, whereas adsorption of an acidic protein reduced adherence. The effect of adsorbed protein on bacterial adherence was of both short and long range. The long-range effect of the acidic proteins in reducing the number of bacteria adhering to hydroxyapatite was related to protein adsorption causing an increase in surface net negative charge, as shown by zeta potential measurement. Basic protein produced a net positive surface charge which facilitated adherence. Within the acidic protein group, the acidic residue percentage of the adsorbed protein was negatively correlated with the number of bacteria adhering, whereas the nonpolar residue percentage was positively correlated with bacterial adherence. Within the basic protein group, the basic residue percentage was correlated with the number of cells adhering. These results indicate the involvement of short-range hydrophobic and ionic interactions in bacterial adherence to protein-coated hydroxyapatite.
Role of type 1 fimbriae in the pathogenesis of ascending urinary tract infection induced by escherichia coli in mice
Authors: Iwahi T , Abe Y , Nakao M , Imada A , Tsuchiya K
Published: January 2020

Escherichia coli mutants defective in the ability to agglutinate guinea pig erythrocytes (HA-) were isolated from a nalidixic acid-resistant derivative, 31-B, of E. coli TN 675 that produces type 1 fimbriae and induces urinary tract infection in mice fed a 5% glucose solution. All nine HA- mutants were defective not only in their ability to agglutinate Candida albicans cells and erythrocytes from various species, but also in their capacity to adhere to mouse bladder epithelial cells. None of the mutants were agglutinated by anti-type 1 fimbriae antiserum. Although most of the mutants were fimbriated when examined by electron microscopy, their fimbriae differed serologically from type 1 fimbriae. All of the mutants showed 100 to 1,000 times lower bacterial recovery from the bladder walls of mice 3 h after inoculation into the bladder and lacked urinary tract infectivity in mice. These results suggest that all of the HA- mutants are defective in type 1 fimbriae production and that type 1 fimbriae facilitate the development of urinary tract infection in mice, probably by mediating bacterial adherence to the bladder epithelial cells.
Alterations in the pathogenicity of Escherichia coli K-12 after transfer of plasmid and chromosomal genes from Shigella flexneri
Authors: Sansonetti P J , Hale T L , Dammin G J , Kapfer C , Collins H H , Formal S B
Published: January 2020

A 140-megadalton plasmid (pWR110), which has previously been associated with virulence in Shigella flexneri, was transferred to Escherichia coli K-12. Segments of S. flexneri chromosomal material were then transferred to the plamid-bearing K-12 strains. The virulence of these transconjugant hybrids was assessed in the HeLa cell model, in ligated rabbit ileal loops, or in the Sereny test. A K-12 strain which harbored only pWR110 invaded HeLa cells, produced minimal lesions in the rabbit ileal mucosa, and was negative in the Sereny test. Plasmid-containing K-12 hybrids which had incorporated various shigella chromosomal regions gave differential reactions in the rabbit ileal loops and in the Sereny test. Analysis of these transconjugants indicated that three regions were linked with virulent phenotypes. These included the his region (when the genes responsible for O-antigen synthesis were cotransferred) and the kcp locus (linked to the lac-gal region). Either of these chromosomal regions was sufficient to allow invasion of the rabbit ileal mucosa. In addition to both of these regions, another shigella chromosomal segment linked to the arg and mtl loci was necessary for fluid production in the rabbit ileal loop and for a positive Sereny reaction. Thus, derivatives of an E. coli K-12 strain, constructed by the stepwise conjugal transfer of a large plasmid and three chromosomal segments from S. flexneri, appeared to contain the necessary determinants for full pathogenicity in a variety of laboratory models.
Fibronectin levels during intraperitoneal inflammation
Authors: Richards P S , Saba T M
Published: January 2020

Fibronectin is a high-molecular-weight opsonic protein known to influence macrophage uptake of nonbacterial particulate matter. The concentration of fibronectin in serum and the quantity of fibronectin in the inflamed peritoneal space were examined in rats after intraperitoneal casein injection. Fibronectin levels were studied in relation to the opsonic activity of the serum, as assayed by the uptake of gelatin-coated. 51Cr-labeled, fixed sheep erythrocytes by adherent peritoneal macrophage monolayers. Intraperitoneal inflammation resulted in a marked increase in peritoneal fluid fibronectin that lasted throughout a 4-day observation period. The opsonic activity of serum also increased after casein challenge at 24, 48, and 72 h. The elevation in the level of fibronectin in the peritoneal space appeared to coincide with or closely precede the maximal increase in concentration of inflammatory peritoneal macrophages. After casein injection, when serum immunoreactive fibronectin increased, an enhancement in phagocytic clearance of blood-borne gelatin-coated test particles was also observed. It is suggested that the elevation of fibronectin in blood during intraperitoneal inflammation may mediate enhanced liver phagocytic function. The increased amount of fibronectin in the inflamed peritoneal space may also influence the phagocytic activity of peritoneal macrophages.
Crossed immunoelectrophoretic analysis of Legionella pneumophila serogroup 1 antigens
Authors: Collins M T , Cho S N , Høiby N , Espersen F , Baek L , Reif J S
Published: January 2020

By crossed immunoelectrophoresis, 85 different antigens were demonstrated in sonicated preparations of Legionella pneumophila serogroup 1 (Lp1). The precipitin patterns of 82 anodic-migrating antigens were numbered and were designated the Lp1 reference system. Eleven antigens were stable to boiling, and seven of these were shown to be surface antigens. One heat-stable surface antigen (antigen no. 61) was highly reactive with limulus amoebocyte lysates and formed a precipitin resembling lipopolysaccharide. Serum from an isolation confirmed case of Lp1 infection and serogroup-specific rabbit antiserum reacted specifically with antigen no. 61, which was designated the serogroup-specific antigen. Normal human and rabbit sera commonly had antibodies to antigen no. 66 of the Lp1 reference system. This antigen is antigenically related to the "common antigen" of Pseudomonas aeruginosa.
Characteristics of a Bacteriophage-Infected Strain of
Pasteurella pestis
Isolated from a Human Case of Plague
Authors: Harrison Daniel N. , Cavanaugh Dan C. , Rust James H. , Marshall John D.
Published: January 2020

A pseudolysogenic strain of
Pasteurella pestis
was isolated from a human in Vietnam. The culture contained a stable mixture of bacteriophage and phage-sensitive and phage-resistant
P. pestis.
Cross-Neutralization of Leptospiral Hemolysins from Different Serotypes
Authors: Alexander A. D. , Wood G. , Yancey F. , Byrne R. J. , Yager R. H.
Published: January 2020

Cross-neutralization studies on leptospiral hemolysins from strains of two antigenically different serotypes,
pomona
and
canicola
, were conducted in sheep. A third strain of serotype
hardjo
that does not produce hemolysin and is antigenically distinct was included for control purposes. Concentrated hemolysins, prepared from supernatant fluids of
canicola
or
pomona
cultures, produced hemolytic anemia in sheep after intravenous injection. Sheep previously infected with hemolysin-producing strains were refractory to effects of homologous or heterologous hemolysins. On the other hand, infection with
hardjo
did not confer immunity to the action of hemolysins. Hemolysin-neutralizing antibodies were demonstrable in sheep previously infected with
pomona
or
canicola
only after challenge with homologous or heterologous hemolysins. Cross-neutralization between two hemolysins were demonstrable in vitro. Hemolysin-neutralizing antibody titers did not correlate with agglutinin titers. Concentrated supernatant fluid of the
hardjo
culture provoked toxic reactions predominantly in sheep previously infected with
pomona
or
canicola
. The causes of these untoward reactions were not determined.
Biological Characteristics of
Clostridium perfringens
Type A Enterotoxin
Authors: Stark Raymond L. , Duncan Charles L.
Published: January 2020

An enterotoxin with the ability to induce fluid accumulation in rabbit ileal loops, erythema in the skin of guinea pigs, and lethality in mice appears in cell extracts (CE) and culture filtrates (CF) of sporulating cells of some
Clostridium perfringens
type A strains. All activities in CE and CF were eluted simultaneously from a Sephadex G-200 column. Different elution patterns were obtained for these activities present in CE and CF. Rabbit immune serum against CF and the active CE fractions eliminated the three biological activities in CE and CF. These activities present in CF and CE were not eliminated by any of the known antitoxins present in diagnostic serum against
C. perfringens
types A, B, C, D, and E. Immunodiffusion studies with immune serum against active CE fractions and CF indicated a precipitin line of identity between CF and CE of NCTC 8798 and other enterotoxin-positive strains but not enterotoxin-negative strains. Disc electrophoresis of active G-200 fractions on 7.0% polyacrylamide gels revealed a single area containing erythemal activity and mouse lethality. Immunodiffusion with acrylamide gels, containing crude fractionated enterotoxin, and immune serum against partially purified enterotoxin revealed a single precipitin band in the same area as the biological activities. Immunoelectrophoresis of CE of enterotoxin-positive and enterotoxin-negative strains also showed one precipitin band which occurred only with enterotoxin-positive strains. These findings suggest that one component is responsible for the biological activities attributed to the enterotoxin.
Cellular Reaction in the Footpad and Draining Lymph Nodes of Mice Induced by Mycobacterial Fractions and BCG Bacilli
Authors: Bekierkunst A. , Levij I. S. , Yarkoni E. , Vilkas E. , Lederer E.
Published: January 2020

Ten micrograms of trehalose-6, 6′-dimycolate (cord factor), injected into the footpad of mice, induced histological changes similar to those following injection of living BCG bacilli. Both materials induced in the draining lymph nodes the formation of granulomas composed of epitheloid cells, macrophages, and small numbers of lymphocytes. Apart from the granulomatous inflammatory process, marked hyperplasia of the lymphoid tissue in the paracortical zone of the nodes and accumulations of macrophages were evident. In some cases, the macrophages were very numerous and replaced part of the lymphoid tissue. Compared to cord factor, wax D showed weak granulomagenic activity. Only slight and transient inflammation was found in the footpads as well as transient slight lymphoid hyperplasia. Wax D also induced small accumulations of macrophages. Complete Freund's adjuvant induced, under the same experimental conditions, large accumulations of macrophages in the draining lymphnode and lymphoid hyperplasia in the paracortical zone. No cellular reaction was seen in the liver, spleen, and lungs after injection of cord factor and BCG into the footpads of the animals. The results and implications are discussed.
Intracellular Location of
Treponema pallidum
(Nichols Strain) in the Rabbit Testis
Authors: Sykes John A. , Miller James N.
Published: January 2020

During investigations designed to obtain purified suspensions of virulent
Treponema pallidum
(Nichols strain), infected rabbit testicular tissue was routinely examined in the electron microscope. Morphologically typical
T. pallidum
were found intracellularly within the cytoplasmic substance of fibroblasts, interstitial and Leydig cells, and of spermatocytes. The importance of these observations to latency and treatment is discussed.
Effect of Infection and Endotoxicosis on Plasma Lactate Dehydrogenase Isozymes in White Rats
Authors: Hale T. Larry , Woodward John M.
Published: January 2020

Vertical slab electrophoresis in polyacrylamide gels was used to monitor changes in lactate dehydrogenase (LDH) isozymes in plasma of white rats during bacterial infection and endotoxin poisoning. Peritoneal infection with
Francisella tularensis
and
Salmonella typhimurium
and administration of
S. typhimurium
endotoxin stimulated significant increases in plasma LDH-5. Rates of change in enzyme activity after infection were directly related to size of infecting dose and type of agent employed. Infection with 1 median lethal dose of
F. tularensis
stimulated both an early, temporary and a prolonged, secondary elevation in LDH-5 activity, whereas salmonellosis, endotoxicosis, killed cells, and latex particles elicited only an initial response of short duration. Changes observed in plasma LDH-5 after exposure to these agents suggest that, as a result of phagocytosis or cell damage, peritoneal leukocytes contribute to early increases in plasma enzyme activity, whereas extensive liver involvement is responsible for high secondary LDH-5 levels during progressive tularemic infection.