bluuebunny/crossref_metadata_2025 huggingface dataset:
Local vaccination with killed Streptococcus uberis protects the bovine mammary gland against experimental intramammary challenge with the homologous strain
Authors: Finch J M , Hill A W , Field T R , Leigh J A
Published: January 2020

The ability of killed streptococcus uberis to induce protection against mastitis when administered either into the cistern of the dry mammary gland (intramammary vaccination) without adjuvant or subcutaneously with adjuvant was investigated. Bacteria were never reisolated from vaccinated quarters following challenge with the same strain during the subsequent lactation, and no inflammatory response was detected. In contrast, following subcutaneous vaccination, milk from challenged quarters contained very small numbers of bacteria, but these quarters did exhibit clinical disease, whereas quarters on nonvaccinated control animals produced discolored, clotted secretion with large numbers of bacteria and somatic cells and required antibiotic therapy by 60 h postchallenge. There was a significant increase in the levels of S. uberis-specific immunoglobulin G1 (IgG1), IgG2, and IgM in milk following intramammary vaccination and in the levels of specific IgG1 and IgG2 in milk following subcutaneous vaccination. Levels of specific antibody in serum were also elevated following vaccination by either route. However, despite this, there was no increase in the opsonic activity of serum or milk. Both peripheral blood lymphocytes and dry-period mammary gland lymphocytes showed strong proliferative responses to S. uberis in vitro following subcutaneous vaccination, but only mammary gland lymphocytes responded following intramammary vaccination. It was concluded that the protection seen in vaccinated quarters did not appear to be related to levels of specific antibody or neutrophil function and was possibly brought about by the inhibition of bacterial growth.
A carAB mutant of avian pathogenic Escherichia coli serogroup O2 is attenuated and effective as a live oral vaccine against colibacillosis in turkeys
Authors: Kwaga J K , Allan B J , van der Hurk J V , Seida H , Potter A A
Published: January 2020

Colibacillosis is a serious and economically important disease of the respiratory tract of chickens and turkeys. The serogroups of Escherichia coli commonly associated with colibacillosis in poultry are O1, O2, and O78. Although previous attempts to develop a vaccine have not been very successful, vaccination is still considered the most effective way of controlling the disease. Therefore, our laboratory has been involved in the development of an attenuated live vaccine that will be effective in the prevention of colibacillosis. The carAB operon coding for carbamoyl-phosphate synthetase, an essential enzyme in arginine and pyrimidine metabolism, was selected for study. Generalized transduction was used to transfer a Tn10-generated mutation from a laboratory strain to virulent avian field isolates of E. coli. Molecular techniques were used to determine the point of Tn10 insertion within the carAB operon. The insertion mutants were then cured of the tetracycline resistance gene of the transposon to select for antibiotic-sensitive and stable carAB mutants. The degree of attenuation obtained by the mutation was determined in day-old chickens. Typically, when 100-fold the 50% lethal dose (for the wild type) was given, no more than 50% mortality in the day-old chickens was observed. The deletion mutant of serotype O2 was also found to be avirulent in turkeys rendered susceptible to infection with hemorrhagic enteritis virus A. Turkey poults vaccinated orally at 4 weeks old with either the wild-type E. coli EC317 strain or its carAB mutant EC751 were completely protected from infection following challenge with the homologous wild-type strain. Our data indicate that carAB mutants of virulent avian strains of E. coli will be effective and safe as live oral vaccines for prevention of colibacillosis in poultry.
A new type of staphylococcal exfoliative toxin from a Staphylococcus aureus strain isolated from a horse with phlegmon
Authors: Sato H , Matsumori Y , Tanabe T , Saito H , Shimizu A , Kawano J
Published: January 2020

A new type of staphylococcal exfoliative toxin (sET) was isolated from the culture filtrate of a Staphylococcus aureus strain isolated from a horse with skin infection including phlegmon. The new sET was purified by precipitation with 80% saturated ammonium sulfate, column chromatography on DEAE-cellulofine A-500, gel filtration on a Sephadex G-75 column, and polyacrylamide gel electrophoresis (7.5% polyacrylamide). The new sET elicited general exfoliation of the epidermis with the so-called Nikolsky sign when inoculated into both 3-day-old mice and 1-day-old chicks, whereas sETA and sETB from human strains of S. aureus caused exfoliation in a 3-day-old mouse alone and shET from a porcine strain of Staphylococcus hyicus caused exfoliation in 1-day-old chicks alone. Intraepidermal splitting was observed at the granular layer of the epidermis of mice inoculated with the new sET as well as those inoculated with sETA. Exfoliation at the germinative layer of the epidermis was also observed in the chicks inoculated with the new sET as well as those inoculated with shET. The new sET was serologically different from sETA, sETB, and shET and showed the same molecular weight on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. It was thermolabile and lost its toxicity after being heated at 60 degrees C for 15 min. We propose that the new sET be designated as sETC.
Characterization of the dermonecrotic toxin in members of the genus Bordetella
Authors: Walker K E , Weiss A A
Published: January 2020

All members of the genus Bordetella and Pasteurella multocida (a gram-negative bacillus genetically unrelated to Bordetella spp., yet often sharing the same ecological niche) produce a dermonecrotic toxin (DNT). The amount of toxin produced and the time required for appearance of the lesions are identical for Bordetella pertussis, B. parapertussis, and B. bronchiseptica but different for P. multocida and B. avium. DNT has been reported to act by promoting vasoconstriction; however, vasoactive compounds (verapamil, prazosin, hydralazine, tolazoline, or isoxsuprine) are able to reverse the action of the toxin only slightly. Vasoconstrictors (atropine, serotonin, epinephrine, or endothelin) did not produce DNT-like lesions. We have characterized a region of DNA essential for DNT expression. We have determined by Southern analysis that the restriction map of the DNT gene is nearly identical in B. pertussis, B. parapertussis, and B. bronchiseptica, but the sequences are not present in toxigenic B. avium and P. multocida strains. A gentamicin resistance-origin of transfer cassette cloned into a 1.8-kb NotI-BamHI fragment results in constructs which can be mobilized and recombined into the Bordetella chromosome, rendering the resultant B. pertussis, B. parapertussis, and B. bronchiseptica strains negative for DNT. A 5-kb BamHI-ApaI fragment from the B. pertussis chromosome was sequenced and revealed homology to the Escherichia coli CNF1 (cytotoxic necrotizing factor 1) toxin.
Cytokine induction in human coccidioidomycosis
Authors: Dooley D P , Cox R A , Hestilow K L , Dolan M J , Magee D M
Published: January 2020

To investigate the immune response to human infection with the fungus Coccidioides immitis, we measured cytokine production from peripheral blood mononuclear cells (PBMC) and plastic-adherent monocytes/macrophages (Mphi) isolated from healthy subjects who were skin test positive to spherulin, healthy subjects who were skin test negative, and patients with active coccidioidomycosis. PBMC and Mphi from all these donor groups secreted increased levels of tumor necrosis factor alpha, interleukin-1 beta, and interleukin-6 in response to stimulation with formalin-killed spherules (FKS), as measured by enzyme-linked immunosorbent assays. Viable C. immitis spherules also stimulated PBMC and Mphi from healthy subjects and patients to secrete tumor necrosis factor alpha, interleukin-1 beta, and interleukin-6, although at levels lower than those induced by FKS. The production of these acute inflammatory cytokines may contribute to the immunopathogenesis of active coccidioidomycosis and could account for the toxicity of the FKS vaccine in humans.
Localized expression of mRNA for phagocyte-specific chemotactic cytokines in human periodontal infections
Authors: Tonetti M S , Imboden M A , Gerber L , Lang N P , Laissue J , Mueller C
Published: January 2020

In bacterial infections, mononuclear and polymorphonuclear phagocytes are key components of host defenses. Recent investigations have indicated that chemokines are able to recruit and activate phagocytes. In particular, interleukin-8 (IL-8) attracts polymorphonuclear leukocytes (PMNs), while monocyte chemoattractant protein-1 (MCP-1) is selective for cells of the monocyte/macrophage lineage. In this investigation, we analyzed the in situ expression of IL-8 and MCP-1 mRNAs in human periodontal infections. Specific mRNA was detected by in situ hybridization using 35S-labeled riboprobes in frozen tissue sections. Phagocytes (PMNs and macrophages) were specifically detected as elastase-positive or CD68+ cells by a three-stage immunoperoxidase technique. Results indicated that expression of phagocyte-specific cytokines was confined to selected tissue locations and, in general, paralleled phagocyte infiltration. In particular, IL-8 expression was maximal in the junctional epithelium adjacent to the infecting microorganisms; PMN infiltration was more prominent in the same area. MCP-1 was expressed in the chronic inflammatory infiltrate and along the basal layer of the oral epithelium. Cells of the monocyte/macrophage lineage were demonstrated to be present in the same areas. The observed expression pattern may be the most economic way to establish a cell-type-selective chemotactic gradient within the tissue that is able to effectively direct polymorphonuclear phagocyte migration toward the infecting microorganisms and modulate mononuclear phagocyte infiltration in the surrounding tissues. This process may optimize host defenses and contribute to containing leukocyte infiltration to the infected and inflamed area, thus limiting tissue damage.
Humoral immune response to the Trypanosoma cruzi complement regulatory protein as an indicator of parasitologic clearance in human Chagas' disease
Authors: Norris K A , Galvão L M , Schrimpf J E , Cançado J R , Krettli A U
Published: January 2020

Immunoprecipitation of the purified 160-kDa complement regulatory protein of Trypanosoma cruzi by Chagas' disease patient sera was examined as a possible correlate of the complement-mediated lysis test and as an indicator of parasite clearance. The results presented demonstrate that assessment of the humoral response to this antigen is a useful indicator of parasite clearance and may be particularly helpful in the assessment of some patients for whom other serological tests produce ambiguous results.
Immunity to
Vibrio cholerae
in the Mouse II. Effect of a Cell-Adherent Immune Factor
Authors: Actor Paul , Pitkin Donald
Published: January 2020

Serum, peritoneal exudate cells, or spleen cells were obtained from donor mice immunized with
Vibrio cholerae
Ogawa 41. Normal recipients were protected from lethal
Vibrio
infection when challenged one day after transfer of immune serum or peritoneal cells or normal peritoneal cells exposed in vitro to immune serum. Protection of recipients of immune spleen cells was evident when the cell transfer-challenge interval was 14 days but not when it was 1 day. Transfer of immunity with peritoneal cells from actively immunized donors was long lasting, whereas that derived from in vitro treatment of normal cells was of short duration. Both a cell-adherent and a nonadhering immune factor appear to be important in this immunity.
Characteristics of Human Antibody to Diphtheria Toxin
Authors: Bazaral M. , Goscienski P. J. , Hamburger R. N.
Published: January 2020

Human antibody to diphtheria toxin was analyzed with an ammonium sulfate radioimmunoassay. In 15 immune sera with titers of between 0.03 and 25 units/ml, the avidity was similar to that of U.S. standard antitoxin. The proportion of the post-immunization anti-diphtheria antibody specific for fragment A was variable, but in the 10 sera tested constituted a substantial fraction of the antibody. Approximately 2% of healthy adult males tested failed to make an antidiphtheria toxin response after two booster doses of 1.5 Lf adsorbed diphtheriatetanus toxoid, although these nonresponders made precipitating antibody to tetanus toxoid and had normal immunoglobulin levels.
Properties of the Enterotoxic Component in
Escherichia coli
Enteropathogenic for Swine
Authors: Jacks Thomas M. , Wu Bo J. , Braemer Allen C. , Bidlack Donald E.
Published: January 2020

The enterotoxic component in sterile syncase broth filtrates of
Escherichia coli
strains 340 (O9:K·:NM) and P307 (O8:K87,88a,b:H19) was studied. The enterotoxic activity in both strains was retained by an ultrafiltration membrane with a molecular weight retention of 100,000 (XM-100A) and eluted from a Sephadex G-200 column in the void volume. The enterotoxic activity in strain 340 was resistant to heating at 75 C for 30 min, but the activity in strain P307 was destroyed by heating at 60 C for 30 min. The P307 Sephadex G-200 column eluate possessing the enterotoxic activity, when desalted, contained 45.8% carbohydrate and 9.3% protein, and had an ED
50
of 2.2 mg/rabbit ileal loop. Immunodiffusion studies showed that this material contained both endotoxin and acid-polysaccharide capsular material. The enterotoxic activity was acidlabile and was destroyed by Pronase, but was resistant to trypsin and eluted as a single peak in the void volume of a 4% agarose column. The enterotoxic component could not be separated from the endotoxin; in fact, the data indicated that the two components are closely associated and that the enterotoxic activity resides in material of a protein nature.
Impaired Chemiluminescence During Phagocytosis of Opsonized Bacteria
Authors: Stjernholm R. L. , Allen R. C. , Steele R. H. , Waring W. W. , Harris Judith A.
Published: January 2020

A simple technique is presented for rapid screening of leukocytes of patients suspected of having a defective intracellular mechanism for the bactericidal and digestive disposal of bacteria.
Role of Delayed Hypersensitivity in Blastomycosis of Mice
Authors: Spencer Harry D. , Cozad George C.
Published: January 2020

C57BL/6J mice rendered hypersensitive to
Blastomyces dermatitidis
were protected from the lethal effects of a blastomyces infection. This protection was observed following a lethal intraperitoneal challenge with viable cells 15 days after subcutaneous inoculation with 3.9 × 10
4
viable cells. Delayed hypersensitivity was induced in C57 mice by two injections of Merthiolate-killed cells in adjuvant or by a single injection of viable cells. Development of hypersensitivity was determined at appropriate intervals by footpad injection with killed yeast cells.
Cross Relationships Among 37 Rhinoviruses Demonstrated by Virus Neutralization with Potent Monotypic Rabbit Antisera
Authors: Cooney M. K. , Kenny G. E. , Tam R. , Fox J. P.
Published: January 2020

Antisera produced in rabbits to 37 rhinovirus (RV) types have been examined for antibody to the 36 corresponding heterologous types. Reciprocal neutralization was noted between RV types 2 and 49 and RV types 13 and 41. Five additional monotypic rhinoviral rabbit antisera neutralized one heterologous rhinovirus. Neutralizing antibody titers against heterologous RV serotypes were similar to those shown in the RV 1A, 1B and RV 9, 32 reciprocal cross-reactions, and would not be expected to result in false identification of serotypes. Comparison of neutralizing antibody titers and neutralization rate constants in serial serum specimens of immunized rabbits showed that antibody response to the immunizing RV type and the cross-reacting type followed a similar time pattern.
Nonhemolytic Group B Streptococci of Human, Bovine, and Ichthyic Origin
Authors: Wilkinson Hazel W. , Thacker L. G. , Facklam R. R.
Published: January 2020

The biochemical and serological characteristics of nonhemolytic group B streptococci of human, bovine, and ichthyic origin were described.
Host Responses to Epstein-Barr Virus and Cytomegalovirus Infection in Leprosy
Authors: Papageorgiou Photini S. , Sorokin Carol F. , Kouzoutzakoglou K. , Bonforte Richard J. , Workman Peter L. , Glade Philip R.
Published: January 2020

A study was undertaken in patients with leprosy to assess the contribution of cell-mediated immunity to the host response to Epstein-Barr virus (EBV) and cytomegalovirus (CMV) infection. Sixteen of 72 patients (22%) with lepromatous leprosy, with impaired cellular immunity, had anti-EBV titers of 1,640 or higher. Only 4 of 49 patients (8%) with tuberculoid leprosy, with intact cell-mediated immunity, attained the level of 1:640. The anti-EBV antibody titers were significantly higher in patients with lepromatous leprosy (
P
≃ 0.025). No significant differences were found in the level of anti-CMV antibody titers in patients with the two types of leprosy. The presence of high anti-EBV antibody titers in lepromatous leprosy suggests that cell-mediated immunity is a significant factor in host response to EBV infection. Host immune responses should be taken into consideration when assignment of an etiological role to EBV is based upon seroepidemiological data.
Inhibition of the Cathepsin D-Type Proteinase of Macrophages by Pepstatin, a Specific Pepsin Inhibitor, and Other Substances
Authors: McAdoo Martha H. , Dannenberg Arthur M. , Hayes Cara J. , James Stephen P. , Sanner John H.
Published: January 2020

The macrophage is the main cell participating in chronic inflammation. It contains an acid-acting, cathepsin D-type proteinase with the specificity of pepsin, which may release mediators of the inflammatory process. To find new pharmaceutical inhibitors of this proteinase, we tested a variety of chemical compounds in vitro. For this survey, the possible inhibitor (at a concentration of 0.4 mg/ml) was assayed with partially purified cathepsin D-type proteinase from beef lung (a macrophage-rich tissue) and hemoglobin as the substrate. Diazophenylbutanone, three acetophenones, two barbiturates, a gold salt, a copper chelate of a substituted nicotinic acid, a hexapeptide containing a
d
-amino acid, and Pepstatin inhibited this enzyme; over 200 other potential inhibitors did not. By far the most active and specific inhibitor found to date is Pepstatin, a pentapeptide with two γ-NH linkages, two β-OH groups, and five branched aliphatic side chains. Banyu Pharmaceutical Co., Tokyo, Japan, produces this nontoxic compound for the treatment of peptic ulcers. In vitro, as little as 4 ng of Pepstatin inhibits the acid-acting cathepsin D-type proteinase purified from beef and rabbit lung as well as the similar proteinase of rabbit peritoneal and pulmonary macrophages.
Different Sensitivity of Ribonucleic and Deoxyribonucleic Acid Viruses to Resistance Induced in Rabbit Cells (RK-13) by Polyriboinosinic Acid·Polyribocytidilic Acid
Authors: Thacore Harshad R. , Youngner Julius S.
Published: January 2020

When a continuous line of rabbit kidney cells (RK-13) was exposed to polyriboinosinic acid polyribocytidilic acid [poly(rI)·poly(rC)], the cells became resistant to the replication of a ribonucleic acid (RNA) virus, vesicular stomatitis (VSV), but remained susceptible to the replication of two deoxyribonucleic acid (DNA) viruses, pseudorabies and vaccinia. These differences were identical to previous findings with RK-13 cells pretreated with exogenous rabbit interferon. Confirmation is thereby provided that RK-13 cells are deficient in the synthesis of resistance factors active against the DNA viruses tested and that there are separate resistance factors for RNA and DNA viruses in RK-13 cells. The resistance against VSV which developed in RK-13 cells exposed to poly(rI)·poly(rC) could be significantly reversed by prior infection with infective vaccinia virus but not by vaccinia inactivated by ultraviolet irradiation or heat.
Immunogenicity of Living and Heat-Killed
Salmonella pullorum
Vaccines
Authors: Collins Frank M.
Published: January 2020

Specific pathogen-free CD-1 and C57Bl mice were infected in a hind footpad with 5 × 10
4
viable
Salmonella enteritidis
cells or 10
7
viable
S. pullorum
cells. The resulting bacterial growth within the footpad, the draining lymph nodes, and the liver and spleen was followed for 14 days. Mice vaccinated with live
S. enteritidis
rapidly developed an effective antibacterial resistance to both intravenous and intragastric challenge with
S. enteritidis
SM
R
. The viable inoculum of
S. pullorum
was rapidly eliminated from the normal mouse tissues and failed to induce a detectable anti-
Salmonella
resistance to parenteral or oral challenge with
S. enteritidis
. Heat-killed saline suspensions (200 μg, dry wt) of
S. enteritidis
or
S. pullorum
were unable to induce an effective antimicrobial resistance against a subsequent virulent
Salmonella
challenge. However, when the organisms were suspended in Freund complete adjuvant, both vaccines induced an antibacterial resistance to intravenous and intragastric challenge. Reduction of the antigenic dose from 200 to 40 μg did not greatly affect the protective value of the two killed vaccines against an intravenous challenge, but the level of protection observed with two 40-μg doses of
S. pullorum
was considerably reduced when the animals were infected intragastrically, suggesting that some quantitative differences existed between the sensitizing antigenic contents of the two test organisms.
Localization and Characterization of the Hippuricase Activity of Group B Streptococci
Authors: Ferrieri Patricia , Wannamaker Lewis W. , Nelson Joann
Published: January 2020

Studies are presented on the isolation, localization, and characterization of hippuricase activity of group B streptococci. Washed, intact cells, live or heat killed at 56 C, exhibited hydrolysis of hippuric acid, but cell-free filtrates of the organism did not. Excellent hippuricase activity was recoverable from supernatant fluids of mechanically disrupted cells, and evidence suggests that it exists largely intracellularly. Characteristics of the hippuricase preparation are consistent with the view that the biologically active principle is an enzyme. A quantitative microtiter technique has been developed which is useful in titrating enzymatic activity and antibody neutralization. Sera from rabbits immunized with filtered preparations neutralized hippuricase activity.
Origin of the Cell-Associated Dextransucrase of
Streptococcus mutans
Authors: McCabe M. M. , Smith E. E.
Published: January 2020

The cell-associated dextransucrase produced by sucrose-grown cells of cariogenic
Streptococcus mutans
K1-R is derived from soluble dextransucrase. Synthesis of insoluble dextran by soluble dextransucrase gives rise to two dextransucrase fractions bound to the insoluble polysaccharide; a reversibly bound enzyme, which can be eluted in solutions of clinical dextran, and an irreversibly bound enzyme, which cannot be solubilized in this manner. Both of these fractions of dextransucrase are also present on sucrose-grown cells. During the synthesis of insoluble dextran by sucrose-grown cells, dextransucrase is progressively converted from soluble enzyme, first to the reversibly bound fraction and then to the irreversibly bound fraction, and is finally inactivated as insoluble dextran accumulates. The two cell-associated dextransucrase fractions therefore represent two stages in the insolubilization and inactivation of their precursor, soluble dextransucrase. As a result of this process of inactivation, the yield of dextransucrase from cells cultured on sucrose is markedly decreased by high concentrations of sucrose in the culture medium.
Virulence of Two Mastitis Strains of
Staphylococcus aureus
in Bovine Skin: Enhancement by Growth in High Carbohydrate-High Salt Medium or in Raw Milk
Authors: Brock J. H. , Turvey A. , Reiter B.
Published: January 2020

Cows were inoculated intradermally with two strains of
Staphylococcus aureus
, and the severity of the resulting skin lesions was assessed on the basis of size, degree of necrosis, and in some cases by measuring the area of inflammation in histological preparations of excised skin. At least 10
6
colony forming units were required to produce a detectable skin lesion, indicating that the cow has a resistance to staphylococcal skin infection comparable to man and rabbit. The severity of the lesions produced by the two strains correlated with their known virulence in the bovine udder as mastitis pathogens. A comparison between lesions produced by cocci grown in a stock laboratory medium and those grown in the high carbohydrate-high salt modified 110 medium showed that the virulence of cocci grown in the latter medium was enhanced. The comparable effect of milk to the modified 110 medium is discussed.
Differences in the Response of Rabbit Small Intestine to Heat-Labile and Heat-Stable Enterotoxins of
Escherichia coli
Authors: Evans Dolores G. , Evans Doyle J. , Pierce Nathaniel F.
Published: January 2020

The response of adult rabbit small intestine to the heat-stable (ST) and heat-labile (LT) enterotoxins of
Escherichia coli
has been investigated by employing the ligated loop technique. Fluid accumulation was determined in relation to enterotoxin dose and duration of gut exposure. The individual responses to ST and LT differed in a characteristic manner. Onset of net fluid accumulation in response to ST appeared to be immediate even at the lowest dose tested. Onset of net fluid accumulation in response to LT was rapid at high doses but delayed at low doses. Maximum volume per length ratios elicited by ST occurred between 4 and 6 h after injection of loops over the entire range of doses tested. However, maximum ratios elicited by LT occurred no less than 10 h after injection even at low doses. Fluid accumulation elicited by LT increased in duration with increasing dose; high doses of LT producing a response which was sustained for at least 18 h. The net effect of these differences in reaction characteristics is a sharp increase in the proportion of the cumulative net secretory response attributable to LT with time. Therefore, a 6-h assay time is appropriate for the titration of ST, whereas an 18-h assay is not. The 18-h assay was found more appropriate for toxin-antitoxin neutralization studies since only LT was neutralized by anti-enterotoxin serum. LT of
E. coli
(swine) strain P-263 and (human) strain 334 was neutralized by antibody stimulated by enterotoxin from
E. coli
(human) strain H-10407. LT was labile to mild acid conditions, whereas ST was not.
Chemical and Serological Properties of
Mycoplasma hyorhinis
Fractions
Authors: Barden Jerri A. , Prescott Benjamin
Published: January 2020

Mycoplasma hyorhinis
organisms were fractionated into lipid, carbohydrate, and protein fractions by chemical and physiochemical procedures. When all fractions were tested for complement fixation and inhibition of growth inhibition activity, only the protein fractions possessed activity. Thus, it appears that the major antigenic component of
M. hyorhinis
is a protein.
Localization of Bacteria in the Gastrointestinal Tract: a Possible Explanation of Intestinal Spirochaetosis
Authors: Leach W. D. , Lee Adrian , Stubbs R. P.
Published: January 2020

The large intestine of rats and dogs was examined by light and electron microscopy. In both species localization of bacteria in specific areas of the tissue was observed. Fusiform bacteria mixed with spirochaetes were seen at the opening of the crypts into the large bowel. However, at the base of the crypts homogeneous populations of spiral organisms were found; some crypts contained
Borrelia
-type spirochaetes, whereas others contained spiral bacteria with other morphology. Very few spiral bacteria, including those of the spirillum type, were seen in the lumen of the large intestine. Experiments in rats showed that mucosa-associated spiral organisms appeared in large numbers in the stools when diarrhea was induced with magnesium sulfate. These observations were taken as a basis for explaining intestinal spirochaetosis of dogs and other animals, a syndrome which has been frequently described and which, until now, has been considered to reflect pathogenicity of these organisms.
Falcon Herpesvirus, the Etiologic Agent of Inclusion Body Disease of Falcons
Authors: Maré C. J. , Graham D. L.
Published: January 2020

A viral agent has been isolated from five fatal cases of naturally occurring inclusion body disease in three different falcon species, namely, the prairie falcon (
Falco mexicanus
), the red-headed falcon (
F. chiquera
), and the peregrine falcon (
F. peregrinus
). The virus has been shown to possess the physical, chemical, and biological properties of a herpesvirus and has been used to reproduce inclusion body disease in the prairie falcon, merlin (
F. columbarius
), and American kestrel (
F. sparverius
). A similar disease was also produced with this virus in the great horned owl (
Bubo virginianus
), screech owl (
Otus asio
), and ring-necked turtle dove (
Streptopelia risoria
). Serological comparison of the falcon herpesvirus with other known avian herpesviruses revealed that the virus is antigenically closely related to a pigeon herpesvirus and an owl herpesvirus while differing from the former in host range. No antigenic relationship to infectious laryngotracheitis virus, duck virus enteritis, or Marek's disease virus could be demonstrated.
Physical Properties and Antigenic Components of Oriboca Virus
Authors: Karabatsos N.
Published: January 2020

Two complement fixation (CF) components were detected in all of the various preparations (mouse liver, brain, serum, and BHK-21 cell culture) of Oriboca examined by equilibrium density centrifugation. The CF components possessed a buoyant density of 1.21 and 1.18 g/ml, and they were precipitated by treatment with protamine. Analysis of Oriboca virus by rate zonal sedimentation separated three components. The most rapidly sedimenting component was the infectivity which cosedimented with a peak of hemagglutinating (HA) activity designated VHA. A second, more slowly sedimenting, noninfectious HA component (HA-2) was followed by a peak of CF activity which barely moved from the top of the gradient. The single rate zonal CF peak and the two density gradient CF components were broadly cross-reactive serologically with Murutucu antiserum. They could not be identified as Oriboca on the basis of their CF reactions with Murutucu and Oriboca antisera. Oriboca-infective virions possessed an equilibrium density of 1.20 g/ml if derived from BHK-21 cell culture fluid concentrates or mouse serum. Infective virions prepared from mouse brain or liver banded at a buoyant density of 1.17 to 1.18 g/ml. These density differences, along with observed differences in reactivity with protamine and in rate of neutralization, are consistent with the interpretation that these are related to the problem of whether the source preparations of Oriboca represented primarily intracellular or extracellular particles.
Acute Cavitary Histoplasmosis in Rhesus Monkeys: Influence of Immunological Status
Authors: Bauman D. S. , Chick E. W.
Published: January 2020

Male rhesus monkeys were randomized into groups according to body weight, immunized with different
Histoplasma capsulatum
antigens, and two weeks later were infected intratracheally with 10
8
H. capsulatum
yeast cells. Complement fixation antibody titers, skin tests, and chest X rays were performed at weekly intervals from immunization until autopsy, at which time the spleens were cultured and the lungs and other organs were dissected. Pulmonary cavities were found in 33% of the animals, and extrapulmonary dissemination was present in 85% of the animals. Delayed hypersensitivity and circulating antibody activity was detected in all animals at some time during the experimental period; however, animals which developed pulmonary cavities had a longer period before circulating antibodies were detected than animals which did not develop pulmonary cavities. Delayed hypersensitivity developed at approximately the same time in both cavitary and noncavitary animals. Early appearance of delayed hypersensitivity was associated with reduced amounts of extrapulmonary dissemination, in that animals with a later onset of skin test reactivity had more
H. capsulatum
cultured from the spleen. There was no correlation between the onset or titers of circulating antibodies and the spleen culture results.
Hypogammaglobulinemia and Thymic Hypoplasia in Horses: a Primary Combined Immunodeficiency Disorder
Authors: McGuire T. C. , Poppie Marinel J.
Published: January 2020

A severe combined immunodeficiency disorder was demonstrated in two Arabian foals which were full siblings. The defect in the B-lymphocyte system was shown by hypogammaglobulinemia, lymphopenia, and absence of germinal centers. The almost total absence of thymic tissue in one foal and the lack of thymic dependent lymphocytes in the spleens of both foals demonstrate a T-lymphocyte defect. In a retrospective study of total available Arabian foal cases, 4 of 15 had evidence of immunodeficiency.
Production of
Haemophilus influenzae
b Meningitis in Infant Rats by Intraperitoneal Inoculation
Authors: Smith Arnold L. , Smith David H. , Averill Damon R. , Marino Joseph , Moxon E. Richard
Published: January 2020

Sprague-Dawley rats have a marked age-related susceptibility to
Haemophilus influenzae
type b that does not correlate with serum bactericidal activity. Eighty percent of 5-day-old animals that survive to 48 h after an intraperitoneal inoculation of a mean lethal dose of bacteria have histologically documented meningitis. Animals surviving the inoculations as infants manifest cerebral dysfunction as adults. This model should facilitate experimental study of bacterial meningitis.
Mechanisms of Immunity in Typhus Infections II. Multiplication of Typhus Rickettsiae in Human Macrophage Cell Cultures in the Nonimmune System: Influence of Virulence of Rickettsial Strains and of Chloramphenicol
Authors: Gambrill Margaret R. , Wisseman C. L.
Published: January 2020

Monocytes from the peripheral blood of nonimmune human subjects transformed in cell culture into macrophages with increased phagocytic capacity for killed typhus rickettsiae. When such cells were exposed to living virulent
Rickettsia mooseri
(Wilmington strain) or
R. prowazeki
(Breinl strain), or to the attenuated E strain of
R. prowazeki
, in the presence of medium containing normal human serum, all three strains readily entered the macrophage, but the subsequent fate varied according to strain and its virulence. Thus,
R. mooseri
grew readily to attain very high intracellular populations which eventually destroyed the macrophage in 3 to 5 days and escaped to infect other cells. Virulent
R. prowazeki
also grew at about the same rate for the first 2 to 3 days but then often abruptly ceased to multiply. Circumstantial evidence suggests a toxic effect on host cells by smaller numbers of
R. prowazeki
organisms than with
R. mooseri.
The attenuated E strain of
R. prowazeki
failed to grow in most cells and eventually disappeared, but did grow to substantial numbers in the very rare cell in some cultures, suggesting the presence of a few cells which may not be typical macrophages. The growth of
R. mooseri
in the macrophage cytoplasm was inhibited by chloramphenicol in the culture medium. When the drug was removed after 3 days, growth began after a lag period and assumed a normal rate.
Stimulation of Anti-
Brucella
Vaccination in Mice by Tetramisole, a Phenyl-Imidothiazole Salt
Authors: Renoux Gérard , Renoux Micheline
Published: January 2020

The effect of tetramisole (hydrochloride of racemic 2, 3, 5, 6,-tetrahydro-6-phenyl-imidazo [2, 1-b] thiazole) on immunization was investigated in mice vaccinated by killed
Brucella melitensis
cells suspended in incomplete adjuvant. Immunity to
Brucella abortus
challenge was estimated by the reduction in number of
B. abortus
colonies per gram of spleen in those mice which escaped full immunization and also by calculation of mean infective doses for each group of mice. All tetramisole treatments significantly reduced the number of
B. abortus
live cells in spleen from infected mice. Tetramisole, injected twice (at the time of vaccination and 48 h later), induced a significant 3.5-fold increase of the protection brought about by
Brucella
vaccine alone. A single injection of 1.25 mg/kg at the time of vaccination resulted also in a significant increase of the immunity given by vaccination. No modifications of the vaccine potency were observed if tetramisole administration preceded vaccination. In such a mouse assay, tetramisole-induced stimulation was not accompanied by specific antibody increases, although measured by three serological tests.
Further Studies on the Inhibition of
Histoplasma capsulatum
Within Macrophages from Immunized Animals
Authors: Howard Dexter H.
Published: January 2020

Mononuclear phagocytes freshly harvested from immunized animals restrict the intracellular growth of
Histoplasma capsulatum
. The fate of the inhibited fungus is the subject of this report. Macrophages harvested from mice immunized by sublethal infection were parasitized in vitro with yeast cells of
H. capsulatum
. The subsequent fate of the fungus was assessed by staining characteristics, viability on subculture, and radioisotopic techniques. No tinctorial distinction could be made between yeasts within normal or immune phagocytes stained by the May Greenwald-Giemsa or by the Gridley techniques. Yeast cells recovered after 24 h of residence within the cytoplasm of immune monocytes excluded the dye eosin-Y, germinated on Casamino Acid agar incubated at 30 C, and initiated growth at a normal rate within phagocytes from normal animals. Thus even though the growth of
H. capsulatum
was inhibited within macrophages from immunized animals, the fungus was not killed by the encounter. However, autoradiographic studies established that protein synthesis by the fungus in situ was impaired.
Resistance of Mice to Infection with Friend Disease Virus After Subcutaneous Injection of Friend Virus and Friend Spleen Cells
Authors: Larson C. L. , Ushijima R. N. , Kasuga S. K. , Baker R. E. , Baker M. B.
Published: January 2020

Swiss mice injected subcutaneously with suspensions of spleen cells or an extract of spleens from mice infected with Friend virus develop resistance to subsequent intravenous inoculation of Friend virus. A single injection of either Friend virus or Friend cells induces resistance. Immunized mice display resistance when challenged 6 months after immunization and survive for at least 20 weeks after infection. Neutralization tests indicate that serum, but not lymphoid cells of resistant animals, can neutralize Friend virus. In vitro neutralization tests indicate that residence of virus within the peritoneal cavity of immune mice for 1 h sharply reduces the infective titer of the virus.
Enhanced Immunoglobulin M and Immunoglobulin G Antibody Titers in Mice Fed Selenium
Authors: Spallholz Julian E. , Martin John L. , Gerlach Marlene L. , Heinzerling Rollin H.
Published: January 2020

Mice fed diets supplemented with selenium (sodium selenite) immunologically respond to the sheep red blood cell antigen by producing enhanced immunoglobulin M and immunoglobulin G antibody titers.
Studies of Peripheral Blood T- and B-Lymphocytes in Acute Infections
Authors: Niklasson Per M. , Williams Ralph C.
Published: January 2020

E-binding (T) and immunoglobulin-bearing (B) lymphocytes were determined in 22 patients with acute infections. The percentage of T-cells was depressed in most patients in the early stages of disease, whereas the B-cell proportion was usually elevated compared with convalescence and controls. The B-cell increase occurred earlier in a small group of viral or mycoplasmal infections than in bacterial infections. Four patients with unusually high numbers of B-cells had no corresponding increase in EAC3-binding lymphocytes. Almost all lymphocytes from pleural effusion in a patient with tuberculosis were found to be T-cells.
Effects of Antithymocyte Sera and Antimacrophage Sera on Cell-Mediated Immune Reactions in
Listeria
-Infected Mice
Authors: Pearson Leonard D. , Osebold John W.
Published: January 2020

The cell-mediated immune responses of allograft rejection, delayed hypersensitivity, and resistance to
Listeria monocytogenes
were suppressed by injections of antithymocyte serum (ATS), but the immune responses were not significantly altered by antimacrophage serum (AMS) or normal rabbit serum (NRS). Antisera were prepared in rabbits against purified mouse thymocytes and purified peritoneal macrophages. When mice were injected with ATS near the time of skin grafting, allografts survived significantly longer. Similar administration of AMS or NRS failed to alter the course of graft rejection. Decreased footpad swelling indicated the suppression of delayed hypersensitivity in mice injected with ATS 6 days after a sublethal inoculation of
Listeria
cells. None of the serum treatments affected the ultimate survival of mice infected with a small number of bacteria. Either ATS or NRS was injected into immunized mice 1 day before and 2 days after a challenge inoculation of
Listeria
cells. Pronounced suppression of delayed hypersensitivity was found in the ATS-treated groups, along with extensive mortalities that reached 100% in the group receiving the largest dose of ATS. All control animals survived and demonstrated strong delayed hypersensitivity reactions. Antimacrophage serum had no significant effect on the three mechanisms of cell-mediated immunity that were tested. The lymphoid cells which mediate delayed hypersensitivity, antimicrobial cellular immunity, and allograft rejection possess antigenic determinants in common with thymocytes.
Isolation of
Clostridium absonum
and Its Cultural and Biochemical Properties
Authors: Hayase M. , Mitsui N. , Tamai K. , Nakamura S. , Nishida S.
Published: January 2020

A new procedure for isolation of
Clostridium absonum
was devised. Sixtyseven strains of
C. absonum
were isolated from 135 soil samples, but no strain of
C. absonum
could be found from human fecal samples. The lecithinase, hemolysin, and lethal toxin in the culture filtrates of this species exhibited low avidity for
C. perfringens
type A antitoxin. The three activities were inseparable by the present method of purification. A reinvestigation of biochemical properties revealed that incomplete suppression of lecithinase reaction by
C. perfringens
type A antitoxin and no fermentation of raffinose, melibiose, and starch are useful criteria to differentiate
C. absonum
from
C. perfringens
, and that positive, although weak, gelatin liquefaction and fermentation of trehalose are useful to differentiate it from
C. paraperfringens.
Lipids of Putative Relevance to Virulence in
Mycobacterium tuberculosis
: Phthiocerol Dimycocerosate and the Attenuation Indicator Lipid
Authors: Goren Mayer B. , Brokl Olga , Schaefer Werner B.
Published: January 2020

Lipid compositions of 40 patient isolates of
Mycobacterium tuberculosis
derived from Madras, Burma, Rangoon, and East Africa were studied, and two major populations of tubercle bacilli were distinguished. Nearly all of the strains previously designated as attenuated for the guinea pig (D. A. Mitchison) are characterized by a specific phenolic phthiocerol diester which is identified with the aglycone moieties of mycosides A and B (and probably G). This lipid (AI) was not seen in any of the more virulent strains. Thus, presence of AI may be taken as definitive for attenuation (
P
≪ 0.001). Phthiocerol dimycoserosate (DIM), a companion substance, is ubiquitous for the series of 40 strains. However, a dramatic attenuation found in a DIM-less H37Rv mutant may support a role for this substance in the virulent state. Since mycosides A, G, and B seem to be restricted to certain chromogenic and bovine species, respectively, we speculate that lysogenization or transduction of fully virulent
M. tuberculosis
may have provided the genetic determinants for attenuation and AI synthesis, and thus led to the two classes of tubercle bacilli.
Selective Decrease in Interferon Production in Immunotolerant Mice
Authors: Lo Grace , Treagan Lucy
Published: January 2020

Mice, immunologically unresponsive to Newcastle disease virus, were impaired in their capacity to produce interferon when induced with Newcastle disease virus, but not when induced with an unrelated virus.
Pathogenesis of Temperature-Sensitive Mutants of Sindbis Virus in the Embryonated Egg I. Characterization and Kinetics of Viral Multiplication
Authors: Schluter Bonnie , Bellomy Bruce , Brown Arthur
Published: January 2020

Exploratory experiments were performed with temperature-sensitive (ts) mutants of Sindbis virus for studies on viral pathogenesis in the embryonated egg, a host which is immunologically underdeveloped. Parent and mutants were found to be virulent at the permissive temperature (33 C), but only the mutants were attenuated at the nonpermissive temperature (38.5 C). The degree of attenuation varied with the mutant and the route of inoculation. Chicks which survived infection by ts mutants at a nonpermissive temperature weighed the same as controls and showed no obvious abnormalities on gross examination. Whenever death of the embryo at the nonpermissive temperature occurred after inoculation with a mutant, it was apparently due to the selection of a population of temperature-insensitive virulent revertants. Kinetic studies showed that, after inoculation of the chorioallantoic membrane and incubation at the permissive temperature, a number of cycles of virus multiplication and dissemination apparently occurred rapidly. At the nonpermissive temperature, multiplication was undetectable. Certain pathophysiological signs were seen in the slower, less virulent infections by the mutants at the permissive temperature that were apparently masked or obscured in the more virulent, rapid infection by the parent. From these results and those reported in a subsequent paper, it appears that ts mutants of viruses possess potential as valuable tools for analyzing pathogenesis and immunity in the intact animal host that are complementary to more conventional approaches which employ normal (temperature-insensitive) viruses.
Effect of Cyclophosphamide on
Histoplasma capsulatum
Infections in Mice
Authors: Cozad George C. , Lindsey Terri J.
Published: January 2020

Mice were injected intraperitoneally (i.p.) with 300 mg of cyclophosphamide (CY)/kg of body weight, and 24 h later were injected i.p. with varying dosages of yeast-phase cells of
Histoplasma capsulatum.
At specific time intervals organs were removed, ground, and cultured to determine the number of viable organisms contained in the spleen, liver, and lungs. Injection of mice with CY was found to cause a dramatic increase in the numbers of parasites isolated from these organs when compared with non-drug-treated controls. Mice given 10
7
yeast cells showed the largest increase in colony numbers. A greater than fivefold increase in the numbers of organisms isolated from the spleens of CY and 10
3
yeast cell-treated mice, as compared with non-drug-treated animals, was observed at all time periods. The general trend for infected control animals was a decrease in colony numbers. All mice given CY plus 10
7
yeast cells intravenously (i.v.) died by day 20 postinfection. Mice given CY and 10
7
yeast cells i.p. showed no evidence of fatal
Histoplasma
infection. Deaths occurring by day 5 in CY-treated animals injected with
H. capsulatum
yeast cells i.v. or i.p. were considered due to bacterial infection or toxicity, or both. Hepatosplenomegaly was observed in mice treated with CY and 10
7
yeast cells of
H. capsulatum.
Enlarged lungs were also noted. CY control mouse spleens weighed 30% less than normal spleens. Organs of animals injected with
H. capsulatum
alone did not vary significantly from those of normal mice. Complete drug-induced suppression of humoral antibody response was achieved for 10 days, as determined by hemagglutination titrations.