bluuebunny/crossref_metadata_2025 huggingface dataset:
Role of outer envelope contamination in protection elicited by ribosomal preparations against Neisseria gonorrhoeae infection
Authors: Cooper M D , Wannemuehler M J , Miller R D , Fedyk M F
Published: January 2020

A recent report (Cooper et al., Infect. Immun. 28:92-100, 1980) demonstrated that immunization of guinea pigs with ribosomal preparations was protective (approximately 90%) against chamber infections with Neisseria gonorrhoeae. Similar protection has been demonstrated with other cellular immunogens such as outer membranes (OM) (92%) or purified lipopolysaccharide (LPS) (83%). Protection of LPS (5 to 100 micrograms) was dose dependent (83% with 100 micrograms). Treatment of LPS with pronase reduced the protection by 50%. Ribosomal preparations contained LPS contamination (3.9%) based on dry weight determinations by 2-keto-3-deoxyoctonate analysis. Analysis of ribosomal preparations isolated from cells after lactoperoxidase-mediated 125I labeling indicated a major OM contamination (Protein I). The ribosomal preparation also contained low levels of succinic and lactic dehydrogenase. Passive hemagglutination tests revealed that sera from guinea pigs immunized with ribosomal preparations also demonstrated antibody to OM proteins and LPS. LPS was able to absorb one line of precipitation seen in immunodiffusion reactions as well as the bactericidal activity of such sera. OM preparations were unable to absorb the remaining precipitin line or remove the bactericidal activity. It appears that LPS is the major antigen responsible for the bactericidal activity seen in ribosome-immune sera.
Role of urease in the formation of infection stones: comparison of ureases from different sources
Authors: Rosenstein I J , Hamilton-Miller J M , Brumfitt W
Published: January 2020

Bacterial and vegetable ureases were found to differ in certain important respects. For maximal clinical relevance, in vitro studies on the pathogenic role of urease should use whole bacterial cells of Proteus spp., and urease inhibitors should be assessed without preincubation of enzyme with inhibitor. Urease from Proteus morganii was very different from ureases of other species of Proteus; this factor should be taken into account when infections with P. morganii are being treated.
Another Colicin V Phenotype: In Vitro Adhesion of
Escherichia coli
to Mouse Intestinal Epithelium
Authors: Clancy Joanna , Savage Dwayne C.
Published: January 2020

Two assays were designed with which isogenic laboratory strains of
Escherichia coli
K-12 with and without ColV plasmids were compared for their ability to adhere in vitro to mouse intestinal epithelium. In both assays, disks of intestinal tissue were exposed to bacteria. In the first, disks were homogenized and the numbers of viable bacteria adherent to them were estimated from colony counts of plates inoculated with dilutions of the homogenates. In the second, bacteria were labeled with [
14
C]aspartic acid; the number of adherent cells per disk was estimated by liquid scintillation spectrometry. Data from each assay were compared by analysis of variance. In both assays, strains bearing the ColV plasmid adhered in two- to threefold-greater numbers than isogenic strains without the plasmid. These differences were highly significant statistically. A non-colicinogenic strain free of the ColV plasmid was selected by treatment of a ColV strain with sodium dodecyl sulfate. In the radioisotopic assay, the ColV strain associated with the epithelium in significantly greater numbers than the cured derivative. A ColV strain was created by conjugation; in the radioisotopic assay this strain bound to epithelium in significantly greater numbers than the recipient strain without the plasmid. The original ColV strain, when negatively stained and examined by electron microscopy, had pili that adsorbed male-specific bacteriophage, whereas its isogenic variant without ColV did not. Some such properties, coded by the plasmid, may increase the virulence of the bacteria.
Effect of Seminal Plasma on
Chlamydia trachomatis
Strain LB-1 in Cell Culture
Authors: Hanna Lavelle , Keshishyan Hermine , Brooks George F. , Stites Daniel P. , Jawetz Ernest
Published: January 2020

Human seminal plasma inhibited formation of strain LB-1 chlamydial inclusions in McCoy cells proportional to the concentration of seminal plasma added after chlamydial adsorption.
Effect of staphylococcal iron content on the killing of Staphylococcus aureus by polymorphonuclear leukocytes
Authors: Repine J E , Fox R B , Berger E M , Harada R N
Published: January 2020

Preincubation of Staphylococcus aureus 502A in broth with increasing concentrations of ferrous sulfate progressively increased their iron content, markedly increased their susceptibility to killing by hydrogen peroxide, and did not alter their susceptibility to killing by polymorphonuclear leukocytes.
Butyrate and propionate: important components of toxic dental plaque extracts
Authors: Singer R E , Buckner B A
Published: January 2020

Extracts of in vitro-cultured human dental plaque contain factors toxic to mammalian cells. Previous studies demonstrated that those toxic factors most readily released from cultured plaque had very low molecular weights and were heat stable. Studies reported here demonstrate that metabolic end products including short-chain fatty acids were present in fractions containing the low-molecular-weight, heat-stable factors. The salts of two of these acids, butyrate and propionate, inhibited proliferation of both mouse L929 cells and human gingival fibroblasts. Furthermore, when tested at concentrations present in plaque extracts, the inhibitory effects of butyrate and propionate accounted for essentially all the inhibitory potential of the extracts. These findings, taken together with those of other groups, suggest that butyrate and propionate, end products of dental plaque metabolism, may have an etiological role in periodontal disease.
Aging and cellular defense mechanisms: age-related changes in resistance of mice to Listeria monocytogenes
Authors: Patel P J
Published: January 2020

Age-related changes in resistance of mice to infection with Listeria monocytogenes were investigated. One-month-old mice exhibited the least resistance, and the resistance level increased over the first few months to reach a maximum by 8 months. Increase in age thereafter was accompanied by a slow but progressive decrease in resistance. Thus, 50% lethal doses for 1-, 8-, and 24-month-old mice were 10(4.2), 10(6.6), and 10(5.2), respectively. In spite of differences in resistance, the growth of Listeria in the organs of mice of different age groups was identical during the first 48 h of infection, regardless of the size of the inoculum. Moreover, both young (3- to 8-month-old) and old (22-month-old or older) mice inoculated with a small dose of Listeria were equally capable of inactivating the bacterial load in their spleens and livers within 8 to 10 days of infection. However, a difference in bacterial growth after day 2 of infection was observed when different age groups of mice were inoculated with a large dose of Listeria. These results suggest that the decreased capacity of aged mice to resist infection with Listeria is not due to deficiency in the innate mechanisms of antibacterial resistance, but instead is due to age-related decline in the capacity to acquire immunologically specific antibacterial immunity.
Assmilation of iron by pathogenic Neisseria spp
Authors: Yancey R J , Finkelstein R A
Published: January 2020

Iron assimilation by Neisseria meningitidis and Neisseria gonorrhoeae has been shown to be important to their growth and virulence. Iron acquisition in vitro was studied in an agar diffusion assay employing the iron-binding protein conalbumin. The ability of various iron compounds to alter the growth-inhibitory effect of conalbumin was investigated. On an equimolar iron basis, citrate-containing iron compounds were most effective; hemin was slightly less effective; ferrous sulfate and ferrous ammonium sulfate were even less effective; and the ferric compounds, ferric nitrate, ferric chloride, and ferric dextran (Imferon), were least effective. The results suggested that, as with Escherichia coli and certain other bacteria, the Neisseria spp. may utilize a citrate-mediated iron transport system. Microbial siderophores were also tested for their ability to relieve the growth-inhibitory effect of conalbumin. Two phenolate siderophores and Desferal enhanced growth inhibition in the deferrated form, but were inactive in the ferrated form. Several trihydroxamates of the ferrichrome family and coprogen were inactive in either the deferrated or ferrated forms. Of the 12 different siderophores tested, only the dihydroxamates (schizokinen, arthrobactin, and aerobactin) were stimulatory, but then only in the ferrated forms. Apparently, even though those siderophores could be utilized as specific iron transport agents by the Neisseria spp., they could not compete with conalbumin for iron under these assay conditions.
Systemic Mycobacterium kansasii infection and regulation of the alloantigenic response
Authors: Collins F M , Cunningham D S
Published: January 2020

Specific-pathogen-free B6D2 F1 hybrid mice were infected intravenously with 10(7) to 10(8) viable Mycobacterium kansasii cells. The growth of the five test strains in vivo was correlated with the level of delayed hypersensitivity to a cytoplasmic protein antigen injected into the footpad. M. kansasii TMC no. 1201 and 1203 gave rise to persisting systemic infections with an early delayed hypersensitivity response (day 7) followed by a profound anergy to the cytoplasmic protein antigen injections. Strains 1204, 1214, and 1217 declined in viability relatively rapidly and failed to induce detectable levels of delayed hypersensitivity. Spleens harvested from mice infected 20 to 30 days earlier with 10(8) M. kansasii 1203 cells contained a T-cell subpopulation capable of suppressing mixed lymphocyte reactions between normal B6D2 and C3H(He) cells. On the other hand, splenic T-cells taken from M. kansasii 1214-infected mice enhanced, rather than suppressed, the indicator mixed lymphocyte reactions. The kinetics of stimulator-suppressor T-cell production within the spleens of the heavily infected mice differed as the two contrasting M. kansasii infections progressed. Such cellular interactions could well be responsible for the observed persistence of the systemic M. kansasii 1203 infection.
Growth of
Bacteroides fragilis
in Rabbit Tracheal Organ Culture: Anaerobiosis and Tissue Respiration
Authors: Murakami Tsukasa , Matsuyama Tohey , Shiraishi Setsuko , Hagihara Bunji
Published: January 2020

Rabbit tracheal explants supporting growth of inoculated
Bacteroides fragilis
in air were shown to keep low oxygen tension. Treating the explants with sodium azide induced high oxygen tension and arrested reversibly the growth of
B. fragilis
.
Preparation and characterization of antisera to electrophoretically purified SA11 virus polypeptides
Authors: Bastardo J W , McKimm-Breschkin J L , Sonza S , Mercer L D , Holmes I H
Published: January 2020

Antisera to SA11 virus proteins were prepared by immunizing rabbits with individual polypeptides separated by polyacrylamide gel electrophoresis under reducing or nonreducing conditions; the resulting antisera were characterized by four immunological methods. Results of complement fixation tests with double-shelled rotavirus particles and sera raised against reduced or unreduced proteins of the outer shell of the virus suggested the presence of common antigenic determinants in the outer capsid layers of SA11 and the Northern Ireland strain of calf rotavirus. In this test, antisera to outer shell polypeptides gp34 (O2) and gp25 (O4) cross-reacted with calf rotavirions, whereas those to p62 (O1) and p26 (O3) reacted only with the homologous virus. Antisera to the reduced outer shell proteins of the virus did not neutralize viral infectivity, nor did they possess hemagglutination inhibition activity. Evidence suggesting the presence of type-specific antigenic determinant(s) in the major inner protein p42 (I4) of SA11 virus, capable of inducing neutralizing antibody, is presented and discussed. Antisera produced against unreduced gp34 and p26 polypeptides of the virus contained type-specific neutralizing antibodies. Polypeptide gp34 was also capable of inducing hemagglutination inhibiting antibody. All of the antisera to unreduced polypeptides had agglutinating activity against double-shelled particles of homologous and heterologous rotaviruses.
Cell walls, peptidoglycans, and teichoic acids of gram-positive bacteria as polyclonal inducers and immunomodulators of proliferative and lymphokine responses of human B and T lymphocytes
Authors: Räsänen L , Arvilommi H
Published: January 2020

In this study, the mitogenic and immunomodulating effects of bacterial cell wall preparations were investigated. Cell walls, peptidoglycans, and teichoic acids from Bacillus subtilis and Staphylococcus aureus Wood 46 activated both human T cells (supplemented with 10% monocytes) and B cells to proliferative and to produce leukocyte migration inhibitory factor. Similar results were obtained with adult and umbilical cord blood cells, suggesting that these bacterial preparations acted as mitogens. Cell walls and peptidoglycans had a modulating effect on purified protein derivative-induced and protein A-induced proliferation. In the presence of suboptimal concentrations of these stimulants, bacterial components enhanced the proliferative response. However, at optimal concentrations of purified protein derivative or protein A, bacterial components suppressed lymphocyte proliferation. Peptidoglycans solubilized by lysozyme activated B lymphocytes but not T cells. Solubilization had no effect on immunomodulating capacity.
Antagonisms among isogenic strains of Escherichia coli in the digestive tracts of gnotobiotic mice
Authors: Duval-Iflah Y , Raibaud P , Rousseau M
Published: January 2020

We have observed that antagonisms occur between isogenic strains of Escherichia coli associated with gnotobiotic mice. The strains differed in the carriage of plasmids or in chromosomal mutations. The plasmid-free strains, in general, inhibited the establishment of plasmid-bearing strains in the gastrointestinal tract of mice. The outcome of the interactions between isogenic pairs, however, depended on the order in which the strains were introduced into the mice. Maintaining the bacterial strains in monoassociation with gnotobiotic mice resulted in the "adaptation" of the bacteria to their host. Thus, in all cases, "adapted" strains became the dominant population in the feces of mice, regardless of whether the adapted strains was introduced into mice before or after its isogenic partner which had been cultured in vitro. The ecological advantage disappeared when the adapted strain was cultured in broth. Ultrastructural differences in cell morphology were observed between strains maintained in vivo and in vitro.
N-acetyl muramyl dipeptide stimulation of bone resorption in tissue culture
Authors: Dewhirst F E
Published: January 2020

N-Acetyl-muramyl-L-alanyl-D-isoglutamine (MDP), a structurally defined fragment of bacterial peptidoglycan, stimulated significant release of previously incorporated 45Ca from fetal rat bones in tissue culture over the concentration range of 0.1 to 10.0 micrograms/ml. MDP-Stimulated bone resorption was not inhibited by the addition of the prostaglandin synthetase inhibitor indomethacin to the culture medium. MDP was neither mitogenic for nor stimulated the release of osteoclast-activating factor from cultured human peripheral blood mononuclear cells. Thus, MDP-stimulated bone resorption in vitro is mediated by a mechanism which is not dependent upon prostaglandins or osteoclast-activating factor. 6-O-Stearoyl-N-acetyl-muramyl-L-alanyl-D-isoglutamine, a lipophilic analog of MDP, was slightly more potent than MDP. Two diastereomers of MDP, N-acetyl-muramyl-L-alanyl-L-isoglutamine and N-acetyl-muramyl-D-alanyl-D-isoglutamine, which are inactive as adjuvants, were at least 1,000 times less active than MDP in stimulating bone resorption. The stereochemical specificity for bone-resorptive activity paralleled that required for adjuvant activity, macrophage activation, and activation of the reticuloendothelial system.
Effects of compromising agents on candidosis in mice with persistent infections initiated in infancy
Authors: Guentzel M N , Herrera C
Published: January 2020

Oral-intragastric inoculation of infant CFW mice with Candida albicans, leading either to lethality or to persistent infection of long duration, provides a useful model for study of the host-pathogen interrelationships in candidosis. Mice were most susceptible to the lethal effects of challenge when 4 to 6 days of age, increasingly resistant up to 10 to 11 days, and then resistant to doses of C. albicans lethal for the younger animals. Older mice harboring persistent infections of the gastrointestinal tract, originally initiated when the animals were 6 days old, were used to study the effects of agents which commonly are administered to cancer patients or which are known to predispose to candidosis. The broad-spectrum antibiotic chloramphenicol, cortisone acetate, X-irradiation, or single high doses of cyclophosphamide (Cytoxan) resulted in markedly enhanced levels of C. albicans in the gastrointestinal tract without systemic spread. Repeated smaller doses of Cytoxan, or treatment with methotrexate or a combination of cortisone acetate and Cytoxan, produced gastrointestinal candidosis associated with invasion and systemic spread. The data indicate that the persistently infected animals provide a realistic model for studying treatments that precipitate candidosis in humans.
Rickettsia sennetsu in human blood monocyte cultures: similarities to the growth cycle of Ehrlichia canis
Authors: Hoilien C A , Ristic M , Huxsoll D L , Rapmund G
Published: January 2020

Microscopic examination of cultured human monocytes infected with Rickettsia sennetsu and stained by the Giemsa method revealed the presence of various organismal growth forms in the cytoplasm of the infected cells. The growth forms were loosely scattered individual organisms, clusters of organisms, various sizes of dense inclusion bodies in intact and vacuolated cytoplasm, and organisms in close proximity to disintegrated monocytes. The appearance and the morphology of these R. sennetsu growth forms were similar to those of Ehrlichia canis propagated in canine monocytes. Specific identification of R. sennetsu was made by staining cultured monocytes with fluorescein-conjugated globulins extracted from the pooled sera of patients recovering from sennetsu rickettsiosis. Mice infected with cultured R. sennetsu developed gross pathological changes indicative of infection, and the organism was demonstrated in their spleens, peritoneal macrophages, and mononuclear blood cells. Human monocyte culture appeared to be more sensitive than the previously used African green monkey kidney cell line (BSC-1) for the isolation of R. sennetsu from samples containing minute infectious quantities of this organism.
Escherichia coli-associated porcine neonatal diarrhea: antibacterial activities of colostrum from genetically susceptible and resistant sows
Authors: Sellwood R
Published: January 2020

Antibacterial properties of colostrum from genetically resistant and susceptible sows in a herd in which only the susceptible sows had acquired natural immunity to K88-positive Escherichia coli have been investigated. Significant differences in antiadhesive and opsonic activities occurred. Colostrum from susceptible sows inhibited the binding of 125I-labeled K88 antigen to brush borders significantly better than did the colostrum from resistant dams. Colostrum from susceptible dams effected more efficient in vitro opsonic phagocytosis and killing of K88 E. coli than did colostrum from resistant dams. Differences in bactericidal properties of colostrum between the two groups of pigs were not significant. Fractionation of colostrum from susceptible dams by gel filtration and ion-exchange chromatography revealed that the fractions rich in immunoglobulin M had the highest opsonic activity, whereas those containing predominantly immunoglobulins G and A were of lower activity.
Lanthanum chloride inhibition of the secretory response to Escherichia coli heat-stable enterotoxin
Authors: Greenberg R N , Murad F , Guerrant R L
Published: January 2020

Escherichia coli heat-stable enterotoxin (ST) appears to cause intestinal fluid secretion by activating intestinal particulate guanylate cyclase. Recent studies suggest that chlorpromazine and quinacrine reduce the intestinal secretory response to ST and activation of guanylate cyclase by ST. We have examined the effects of lanthanum chloride, another agent that has been shown to inhibit calcium-dependent cellular processes, on the intestinal secretory response to ST and on the inhibition of ST by chlorpromazine and quinacrine. Lanthanum (2.5 to 10 mumol per mouse) reduced ST-mediated intestinal fluid secretion in the suckling mouse assay by 40 to 56%, respectively, but did not reduce basal fluid accumulation or ST activation of particulate guanylate cyclase. Intestinal fluid secretion in suckling mice induced by 8-bromocyclic GMP was also reduced by lanthanum. When subeffective doses of lanthanum and chlorpromazine were combined, they blocked both ST- and 8-bromocyclic GMP-mediated gut secretion in suckling mice. Likewise, the combination of subeffective doses of lanthanum and quinacrine reduced ST-mediated gut secretion in suckling mice. However, 8-bromocyclic GMP-induced secretion was not synergistically inhibited by lanthanum and quinacrine. These results suggest that lanthanum blocks ST-induced secretion after ST activation of guanylate cyclase. Additionally, lanthanum potentiates the inhibitory effects of quinacrine and chlorpromazine on ST and suggests that combination antisecretory therapy deserves further exploration.
Pulmonary toxicity of endotoxins: comparison of lipopolysaccharides from various bacterial species
Authors: Helander I , Saxén H , Salkinoja-Salonen M , Rylander R
Published: January 2020

Lipopolysaccharides from three gram-negative bacteria isolated from bale cotton and piggery air were analyzed for their chemical composition, and their pulmonary toxicity for guinea pigs, lethal toxicity for mice, and pyrogenicity for rabbits were measured. Lipopolysaccharides from Enterobacter agglomerans and Citrobacter freundii had closely related chemical compositions; both were pyrogenic for rabbits and caused a dose-dependent influx of polymorphonuclear leukocytes into the airways of guinea pigs. The lethal toxicities of these lipopolysaccharides in mice were comparable to that of Salmonella typhimurium lipopolysaccharide, which was used as a reference. Lipopolysaccharide from Agrobacterium sp. was chemically different from those of E. agglomerans and C. freundii, did not induce any influx of polymorphonuclear leukocytes, and was only weakly toxic or pyrogenic. The low biological activity of the agrobacterial lipopolysaccharide may be due to its different chemical composition.
Spontaneous production of gamma interferon and induced production of beta interferon by human T-lymphoblastoid cell lines
Authors: Morris A G , Morser J , Meager A
Published: January 2020

Two human T-lymphoblastoid cell lines, CCRF/CEM and Molt 4, produced beta interferon (IFN-beta) upon infection with Sendai virus. Molt 4, but not CCRF/CEM, spontaneously produced up to 300 U of IFN-gamma per ml, apparently not contaminated with IFN-alpha or -beta. Phytohemagglutinin, a T-cell mitogen, did not stimulate IFN production in these lines. A third T-lymphoblastoid line, CCRF/HSB2, produced no IFN either spontaneously or after infection with Sendai virus or treatment with phytohemagglutinin. The Molt 4 cells contained an mRNA which could be translated by oocytes to give IFN-gamma. Molt 4 cells therefore provide a convenient source of human IFN-gamma and its mRNA for experimental purposes.
Growth rates of Actinomyces viscosus and Streptococcus mutans during early colonization of tooth surfaces in gnotobiotic rats
Authors: Beckers H J , van der Hoeven J S
Published: January 2020

Germfree Osborne-Mendel rats were monoassociated with Actinomyces viscosus or Streptococcus mutans. The adherence and subsequent growth of these organisms on the tooth surface was studied by means of total viable cell counts. Both A. viscosus and S. mutans showed a lag phase and an exponential growth phase, similar to logarithmic growth in batch cultures. The exponential growth rates of S. mutans and A. viscosus were 0.63 h-1 (doubling time [td] = 1.1 h) and 0.24 h-1 (td = 2.9 h), respectively. After a period of rapid growth, the rate declined and the populations approached a steady state. The presence of a sucrose-containing diet did not significantly influence the exponential growth rates of A. viscosus and S. mutans, but had a slight negative effect on the initial adherence of S. mutans at the tooth surface.
Contractile effects of bacterial cell walls, their enzymatic digests, and muramyl dipeptides on ileal strips from guinea pigs
Authors: Ogawa T , Kotani S , Tsujimoto M , Kusumoto S , Shiba T , Kawata S , Yokogawa K
Published: January 2020

Cell walls isolated from four bacterial species (Streptococcus pyogenes, Lactobacillus plantarum, Streptomyces gardneri, and Nocardia corynebacteriodes), which exhibited the adjuvant effect of stimulating cellular and humoral immune responses against ovalbumin in guinea pigs, caused the slow-starting and long-lasting contraction of guinea pig ileal strips suspended in Tyrode solution. In contrast to these cell walls active in immunoadjuvancy, those isolated from five bacterial species (Micrococcus lysodeikticus, Staphylococcus epidermidis, Arthrobacter atrocyaneus, Corynebacterium insidiosum, and Ampullariella regularis), which lacked immunoadjuvancy at least in intact walls, caused no or very weak contraction of the ileal strips. Further study demonstrated that both a monomer and a polymer of disaccharide-stem peptides, which were obtained by enzymatic degradation of S. epidermis cell wall peptidoglycans, displayed similar contractile effects. It was finally revealed that guinea pig ileum strips showed a definite contractile response to N-acetylmuramyl-L-alanyl-D-isoglutamine (MDP) and 6-O-stearoyl- and 6-O-(2-tetradecylhexadecanoyl)-MDPs, but not to their analogs, whose C-terminal amino acid was L-isoglutamine or D-isoasparagine in place of D-isoglutamine and which lacked adjuvancy. 6-O-(3-Hydroxy-2-docosylhexacosanoyl)-MDP, on the other hand, caused a slow and lasting relaxation of the ileum strips, but its L-isoglutamine and D-isoasparagine analogs did not.
Enteropathogenicity of Aeromonas hydrophila and Plesiomonas shigelloides: prevalence among individuals with and without diarrhea in Thailand
Authors: Pitarangsi C , Echeverria P , Whitmire R , Tirapat C , Formal S , Dammin G J , Tingtalapong M
Published: January 2020

To evaluate the enteropathogenicity of Aeromonas hydrophila and Plesiomonas shigelloides, the rate of isolation of these organisms was compared among individuals with and without diarrhea in Thailand. In two groups of American travelers, A. hydrophila, but not P. shigelloides, was associated with episodes of travelers diarrhea more often than when individuals did not have diarrhea (P less than 0.025). Among three populations of Thais, A. hydrophila and P. shigelloides were isolated with similar frequencies from individuals with and without diarrhea. The biochemical characteristics, production of cytotoxin, and ability to distend suckling mouse intestine were similar among A. hydrophila isolates from individuals with and without diarrhea. However, cytotoxic A. hydrophila strains distended rabbit and suckling mouse intestine and produced destructive lesions in intestinal mucosa of both species of animal. P. shigelloides strains produced neither cytotoxin nor distended intestine. Oral administration of whole cultures (10(9)) of cytotoxic A. hydrophila or P. shigelloides failed to cause diarrhea in rhesus monkeys. Volunteer studies or intestinal biopsies of patients with diarrhea may be required to establish whether A. hydrophila is a gastrointestinal pathogen in humans.
Localization of Mycoplasma pulmonis in cartilage
Authors: Kohn D F , Magill L S , Chinookoswong N
Published: January 2020

Transmission electron microscopy of articular cartilage in Mycoplasma pulmonis-infected neonatal rats revealed the presence of mycoplasmas within the matrix and lacunae. The mycoplasmas appeared to have a tropism for the chondrocytes and induced lysis of both the chondrocytes and matrix of the cartilage.
Serological heterogeneity among fimbrial antigens causing mannose-resistant hemagglutination by uropathogenic Escherichia coli
Authors: Clegg S
Published: January 2020

Serological agglutination tests were used to determine cross-reactivity among mannose-resistant fimbrial hemagglutinins of uropathogenic Escherichia coli. Of 47 E. coli strains demonstrating mannose-resistant activity, 12 were agglutinated by one fimbrial antiserum and two reached with a second serum. The mannose-resistant hemagglutinins (fimbriae) of urinary E. coli exhibit antigenic heterogeneity.
Immunological Cross-Reactivities of Woodchuck and Hepatitis B Viral Antigens
Authors: Millman Irving , Halbherr Theresa , Simmons Heidi
Published: January 2020

Woodchuck sera were tested for antigens and antibodies with tests which detect human hepatitis virus antigens and antibodies. Data on 264 woodchuck sera are presented.
Purification and characterization of toxins A and B of Clostridium difficile
Authors: Sullivan N M , Pellett S , Wilkins T D
Published: January 2020

Toxin preparations were obtained by growing Clostridium difficile VPI strain 10463 in 2-liter brain heart infusion dialysis flasks at 37 degrees C for 3 days. The initial step of the purification scheme involved ultrafiltration through an XM-100 membrane filter. Two toxic activities, designated toxins A and B, were separated by ion-exchange chromatography on DEAE-NaCl gradients. Toxin A was purified to homogeneity by an acetic acid precipitation at pH 5.5. Other separation techniques, including CM Sepharose CL-6B, (NH4)2SO4 and acetic acid precipitations, and hydrophobic interaction chromatography, were examined in attempts to further purify toxin B. Although these methods failed to increase the specific activity of toxin B, they provided additional evidence that the two toxins are distinct molecules. The toxins are acid and heat labile and are inactivated by trypsin and chymotrypsin, but not by amylase. The molecular weight of toxin A, as estimated by gel filtration and gradient polyacrylamide electrophoresis, ranged from 440,000 to 500,000. The estimated molecular weight of toxin B was 360,000 to 470,000.
Initial herpes simplex virus type 1 infection prevents ganglionic superinfection by other strains
Authors: Centifanto-Fitzgerald Y M , Varnell E D , Kaufman H E
Published: January 2020

The ganglia of rabbits infected with a relatively benign strain of herpesvirus (E-43) and challenged with either of two virulent neurotrophic strains (MP or McKrae) were found to be colonized only by the initial benign infecting strain. Primary infection with the E-43 strain resulted in milder disease when the animals were infected with MP or McKrae strains and also prevented colonization of the ganglion by these strains. Neutralization with anti-glycoprotein C, plaque morphology, cytopathic effects, reconstruction experiments, and restriction endonuclease analysis indicated that the virus recovered from the ganglion was the initial infecting E-43 strain; no traces of the challenging MP and McKrae strains were found. The challenging McKrae strain was shed for several weeks in a few animals, but the virus isolated from the trigeminal ganglia of these animals was the primary infecting E-43 strain. These results suggest that initial infection with a relatively benign strain of herpesvirus may prevent superinfection of the ganglion (but not necessarily the end organ) by highly virulent herpes simplex virus strains and could have significant implications in the consideration of immunization against this disease in humans.
Characterization of Opsonins for
Bacteroides fragilis
in Immune Sera Collected from Experimentally Infected Mice
Authors: Ellis Thomas M. , Barrett James T.
Published: January 2020

Serum collected from mice experimentally infected with
Bacteroides fragilis
23745 (immune serum) was analyzed for its ability to opsonize the in vitro ingestion of this organism by mouse peritoneal macrophages.
B. fragilis
was shown to be phagocytized most efficiently in the presence of immune serum although normal mouse serum demonstrated reduced, but significant, opsonic activity. Phagocytosis was greater in the presence of serum collected from animals inoculated twice with the organism than in the presence of serum from once-inoculated animals. The increased opsonic activity of serum from twice-inoculated animals compared to singly inoculated animals was associated with increases in immunoglobulin G1(IgG1), IgG2a, and IgG2b but not IgM. Adsorption analysis of immune serum with homologous or heterologous bacterial antigens indicated that both antibody and complement act synergistically in opsonizing
B. fragilis
, although either alone may effectively opsonize this organism. Further evaluation of antibody-mediated opsonization revealed that prior treatment of heat-inactivated immune serum with the reducing agent 2-mercaptoethanol caused a slight, but significant, decrease in opsonic activity, thus indicating that IgM is a minor opsonizing antibody for
B. fragilis.
When ingestion of a
B. fragilis
stock strain (23745) was compared to a recent clinical isolate (C-1), it was observed that the stock strain was more easily phagocytized in the presence of normal mouse serum, thus suggesting a possible anti-opsonic-phagocytic property of the clinical strain. In addition, the clinical isolate was phagocytized to a significantly greater degree in an aerobic than an anaerobic environment. Subsequent analysis of in vitro killing of
B. fragilis
23745 by peritoneal macrophages reflected the previous results in that optimal killing occurred in the presence of immune serum, although normal serum promoted phagocytic killing to an intermediate degree. Thus, these studies implicate both antibody and complement, either alone or in combination, in the opsonization of
B. fragilis.
Moreover, the virulence of clinical
B. fragilis
strains may relate to their refractoriness to opsonization and phagocytosis.
Attachment of Mycoplasma pneumoniae to hamster tracheal organ cultures, tracheal outgrowth monolayers, human erythrocytes, and WiDr human tissue culture cells
Authors: Chandler D K , Collier A M , Barile M F
Published: January 2020

Virulent strains of Mycoplasma pneumoniae, PI-1428 and M129, were radiolabeled wtih [3H]palmitic acid or [3H]thymidine and examined for attachment to hamster tracheal organ cultures, tracheal outgrowth monolayers, human O-positive erythrocytes, and human WiDr carcinoma cell cultures. Although attachment to each cell substrate was readily detected, the WiDr cell culture monolayers provided the most satisfactory substrate for quantitating mycoplasma attachment. Serious technical limitations were encountered with each of the other substrates that we examined; these limitations interfered with reproducibility or sensitivity and rendered tracheal organ cultures and erythrocyte suspensions unsuitable for routine attachment and attachment inhibition assays. Moreover, the WiDr cell monolayer was the most sensitive substrate for determining attachment inhibition activity in protein-containing extracts prepared from M. pneumoniae. The significance of these findings is discussed.
Kinetics of early cholera infection in the removable intestinal tie-adult rabbit diarrhea model
Authors: Spira W M , Sack R B
Published: January 2020

The colonization of the small intestine of adult rabbits challenged with 5 X 10(7) cells of Vibrio cholerae strain Ogawa 395 has been examined in the removable intestinal tie-adult rabbit diarrhea (RITARD) model. During the first 6 h of infection, numbers of both free and adherent vibrios increased at a rate representing a generation time of about 71 min. Detectable fluid output in response to infection began at about 4 to 5 h postchallenge, and overt diarrhea was observed as early as 11 h. By 8 h after challenge, adherent V. cholerae reached a saturation concentration on the intestinal epithelium of approximately 5 X 10(8) cells per g of intestine, whereas numbers of free cells continued to increase at an exponential rate for at least 12 to 14 h. The concentration of adherent cells remained relatively constant at the saturation level during this period. This saturation level was similar in all parts of the small intestine. The concentration of adherent organisms increased significantly in moribund animals, suggesting that factors responsible for the earlier saturation equilibrium began changing as animals neared death.
Purification of a Reiter treponemal protein antigen that is immunologically related to an antigen in Treponema pallidum
Authors: Petersen C S , Pedersen N S , Axelsen N H
Published: January 2020

A protein antigen called TR-o was isolated from supernatant of a sonically treated Reiter treponeme. The isolation procedure included anion-exchange chromatography on Whatman DE-52, hydrophobic interaction chromatography on decyl agarose, and finally gel filtration on Ac-A-22 Ultrogel. The fractionations were monitored by immunoprecipitation techniques. The recovery was found to be 35%, and the isolated protein was enriched 220 times. The molecular weight of the native protein was estimated to be 550,000 by polyacrylamide gel electrophoresis and 450,000 by gel filtration. Only one 66,000-molecular-weight polypeptide was found by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the purified protein. The protein was immunologically pure when tested in crossed immunoelectrophoresis against polyspecific rabbit anti-Reiter immunoglobulin, detecting more than 40 treponemal antigens. A monospecific antiserum was raised in rabbits immunized with the purified protein. Monospecific rabbit anti-TR-o gave strong fluorescence with both the Reiter treponeme and Treponema pallidum. The corresponding antigen in T. pallidum could not be demonstrated directly in a crude T. pallidum sonic extract, but rabbit anti-T. pallidum immunoglobulin contained precipitating antibodies against the purified protein. No antibodies against TR-o were found in selected sera from patients with secondary syphilis reactive in traditional syphilis tests.
Effect of estradiol and progesterone on lymphocyte and neutrophil functions in steers
Authors: Roth J A , Kaeberle M L , Hsu W H
Published: January 2020

Polymorphonuclear leukocyte function and lymphocyte blastogenesis in response to mitogens were evaluated in castrated male cattle after the repeated administration of estradiol or progesterone. Polymorphonuclear leukocyte function was evaluated with the following five parameters: (i) random migration under agarose, (ii) ingestion of 125I-labeled Staphylococcus aureus, (iii) nitroblue tetrazolium reduction, (iv) iodination, and (v) antibody-dependent cell-mediated cytotoxicity. The administration of high dosages of estradiol cypionate produced no measurable effect on the total or differential leukocyte count, neutrophil function, lymphocyte blastogenesis, or blood cortisol levels. The administration of high dosages of progesterone caused a significant enhancement of random migration by neutrophils and a depression of the activity of the myeloperoxidase-H2O2-halide antibacterial system (iodination) of the neutrophil. Progesterone administration did not cause a measurable effect on the lymphocyte blastogenic response to mitogens or the ability of polymorphonuclear leukocytes to ingest S. aureus, reduce nitroblue tetrazolium, or mediate antibody-dependent cell-mediated cytotoxicity. Progesterone did not cause a change in blood cortisol concentrations; therefore, the observed effects on polymorphonuclear leukocyte function were not due to alterations in blood cortisol concentrations. Impairment of the iodination reaction indicates that high dosages of progesterone interfere with an important bactericidal mechanism of the neutrophil.
Incubation of trypanosome-derived mitogenic and immunosuppressive products with peritoneal macrophages allows recovery of biological activities from soluble parasite fractions
Authors: Sacks D L , Bancroft G , Evans W H , Askonas B A
Published: January 2020

This report describes further attempts to define the nature of the parasite product(s) responsible for the extensive changes in lymphoid tissue in mice during infection with Trypanosoma brucei. As previously described, potent mitogenic and immunosuppressive effects are induced by a trypanosome-derived crude membrane fraction in vivo. There was no enrichment in these activities when purified parasite surface membranes were used. Mitogenic activity can be recovered from soluble trypanosome material only when it is incubated with peritoneal macrophages before transfer into syngeneic recipients. Thus, by encouraging association with a critical target cell, soluble parasite products can be studied, and their active components can be separated by conventional methods. Preliminary fractionation of high-spin trypanosome supernatant over Sepharose 4B confined the mitogenic activity to the high-molecular-weight fraction, which is a macromolecular complex of proteins, glycoproteins, and lipid. Extracted lipid from this material was able to significantly suppress a primary immunoglobulin G anti-sheep erythrocyte response. The activity was periodate sensitive and pronase resistant. The use of macrophages in vitro may be a general method whereby important biological activities lost as a result of fractionation procedures can be recovered and the active components studied in greater detail.
Effect of murine cytomegalovirus infection on mitogen responses in genetically resistant and susceptible mice
Authors: Allan J E , Shellam G R , Grundy J E
Published: January 2020

Suppression of the blastogenic response of spleen cells was found during murine cytomegalovirus infection of the genetically susceptible BALB/c and also the more resistant BALB.K strains of mice. These results were observed for both the T-cell mitogen concanavalin A and the B-cell mitogen lipopolysaccharide. As the viral inoculum was increased, there was greater immunosuppression within each strain, the time of maximum depression coinciding with peak virus titers in the spleen. Although both strains developed similar splenic virus titers and exhibited a similar decrease in the proportion of splenic T-lymphocytes, there was greater suppression of the mitogenic response during sublethal infection of the more susceptible BALB/c strain. The suppression could not be readily accounted for by the presence of suppressor cells or by a change in sensitivity to mitogen. The results suggest that the extent of immunosuppression induced by murine cytomegalovirus is determined in part by host genotype.
Enterotoxigenic
Escherichia coli
Strains that Express K88 and 987P Pilus Antigens
Authors: Schneider Robert A. , To Sam C. M.
Published: January 2020

Two enterotoxigenic
Escherichia coli
strains from different sources expressed K88 and 987P pilus antigens.
Inhibition of lymphocyte activation by hatching fluid from Schistosoma mansoni eggs
Authors: Wright E P , Guthrie C D , Salim D , Hilditch T J , Das P K
Published: January 2020

A preparation of the fluid released upon hatching of the miracidia from Schistosoma mansoni eggs was found to have a potent inhibitory effect on the in vitro activation of hamster lymphocytes by mitogens. The effect was concentration dependent, not cytotoxic, and was the same on cells from healthy and schistosome-infected animals.
Involvement of prostaglandin E1 in delayed-type hypersensitivity suppression induced with live Mycobacterium bovis BCG
Authors: Kato K , Yamamoto K
Published: January 2020

We previously showed the suppression of delayed-type hypersensitivity produced by live BCG-induced, plastic-adhering cells. The present study was undertaken to determine whether prostaglandin was one of the pharmacological mediators involved in this suppression. A high level of prostaglandin E1 was detected in the culture supernatant fluid of the live BCG-induced, adherent cells. Moreover, prostaglandin E1 could suppress the macrophage migration inhibition activity of peritoneal exudate cells from BCG cell wall-sensitized mice.
Human peripheral blood lymphocyte activation by protein A from Staphylococcus aureus
Authors: Chen W Y , Sager S , Tung E , Fudenberg H H
Published: January 2020

Mitogenesis and polyclonal immunoglobulin production in peripheral blood lymphocyte cultures activated with Formalin-fixed or autoclaved protein A-containing Staphylococcus aureus were studied. Direct evidence for a dissociation between cell proliferation and polyclonal immunoglobulin production was found, in that S. aureus was not mitogenic after being autoclaved but retained the ability to stimulate B cells to produce immunoglobulin. Trypsin-treated S. aureus lost its binding site for immunoglobulin G, but its mitogenicity was not altered; thus, the protein A binding site for immunoglobulin G on the bacterial cell wall is not required for the stimulation of lymphocyte proliferation. Our data also show a dissociation between cell proliferation and polyclonal immunoglobulin production induced by protein A coupled to Sepharose CL-4B. These results suggest the presence of three distinct active sites on the protein A molecule: one that binds immunoglobulin G molecules, one that stimulates cell proliferation, and one that stimulates polyclonal immunoglobulin production.
Direct correlation between delayed footpad reaction and resistance to local bacterial infection
Authors: Mitsuyama M , Nomoto K , Takeya K
Published: January 2020

The resistance to bacteria was studied at the site of delayed footpad reaction in mice immunized with Listeria monocytogenes. When a challenge injection of listeria was given into the footpad of immune mice, no enhancement of bacterial elimination was observed before the generation of delayed footpad reactivity. After the generation of delayed reactivity, an enhanced elimination of listeria or Salmonella typhimurium was observed only at the site of strongly positive delayed footpad reaction elicited with listerial antigen. Such an enhancement in bacterial elimination was also found at the site of delayed footpad reaction induced by immunization with heterologous erythrocytes. Both delayed footpad reaction and local resistance could be transferred locally by immune spleen cells in a dose-dependent fashion, but were completely abrogated when recipient mice were treated with carrageenan or whole-body X irradiation. Macrophage accumulation was an important factor in the expression of resistance at the reaction site. These results suggest that the delayed footpad reaction contributes to host defense by enhancing the local resistance to bacteria.