bluuebunny/crossref_metadata_2025 huggingface dataset:
Modulation of immune response by killed Brucella abortus organisms: comparison of the effects of smooth and rough strains on T-dependent responses
Authors: Martin A , Le Garrec Y , Dazord L , Toujas L
Published: January 2020

Inactivated Brucella abortus organisms of the smooth (S) or rough (R) strain were tested comparatively on two T-dependent immune responses: mixed-lymphocyte reaction and delayed-type hypersensitivity. The intravenous injection of S organisms depressed the two tests, whereas R organisms increased mixed-lymphocyte reaction and did not alter delayed-type hypersensitivity significantly. This observation may be helpful in understanding the differences in adjuvant properties of S and R brucellae.
Requirement for a Radiosensitive Lymphoid Cell in the Generation of Lipopolysaccharide-Induced Rejection of a Murine Tumor Allograft
Authors: Berendt Michael J. , Mezrow Gail F. , Saluk Paul H.
Published: January 2020

Lipopolysaccharide-initiated rejection of a tumor allograft requires the cooperation of a radiosensitive nonadherent lymphoid cell population and an adherent cell, presumably a macrophage.
Opposite Effects of BCG on Spleen and Lymph Node Cells: Lymphocyte Proliferation and Immunoglobulin Synthesis
Authors: Turcotte R. , Lafleur L. , Labrèche M.
Published: January 2020

C57BL/6 mice were immunized intravenously (i.v.), intraperitoneally (i.p.), or subcutaneously with one dose of
Bacillus
Calmette-Guérin (BCG). At various time intervals after injection, the lymphocyte response, as measured by thymidine incorporation into DNA, and the number of immunoglobulin-secreting cells were determined in vitro before and after mitogenic stimulation with phytohemagglutinin, concanavalin A, or lipopolysaccharide. In unstimulated cultures, the spontaneous thymidine incorporation and immunoglobulin synthesis of spleen cells were increased to some extent in mice infected i.p. or i.v. with BCG, as compared with noninfected mice. In contrast, after mitogenic stimulation, a marked depression of the proliferative response of spleen cells to both T- and B-cell mitogens and a marked inhibition of LPS-induced immunoglobulin secretion were observed in mice infected i.v. and to a lesser extent in those infected i.p. The depression of lymphoblastogenesis in spleens was fully established 15 days after infection and persisted for a long period of time. When unfractionated or plastic-adherent spleen cells from BCG-infected mice were cultured with normal spleen cells, a strong depression of their reactivity to phytohemagglutinin, concanavalin A, and lipopolysaccharide was observed. After the removal of cells adherent to plastic, the response was partially restored in the nonadherent population from mice infected i.p., but not in that from mice infected i.v. After mitogenic stimulation, lymph node cells of mice inoculated subcutaneously showed a response to mitogen higher than that of normal cells. These results thus demonstrate that, depending on the route of administration, BCG exerts very different effects.
Infections of Congenitally Athymic (Nude) and Normal Mice with Avirulent and Virulent Strains of Venezuelan Encephalitis Virus
Authors: LeBlanc Paul A. , Scherer William F. , Sussdorf Dieter H.
Published: January 2020

Two strains of Venezuelan encephalitis virus that are avirulent for normal BALB/c mice inoculated subcutaneously were also avirulent for infected congenitally athymic (nude) mice of the same strain. Viremias were of similar magnitudes and durations in normal and nude mice. Brain concentrations were higher in nude mice with the one avirulent strain tested, although the periods of detectable virus in brains were similar. No lesions were found in brains, spleens, or lymph nodes by ordinary histopathological examination. Viral neutralizing antibody titers in plasmas at 1 to 3 weeks after infection were lower and more transient in nude than in normal mice, and implantations of thymic tissues into nude mice partially restored their neutralizing antibody responses. Concentrations of spleen cells producing antibodies that lysed sheep erythrocytes 4 days after inoculation of erythrocytes and avirulent virus into nude mice were above the levels of uninfected nude mice. These concentrations were similar in infected and uninfected normal mice. In contrast, two mouse-virulent strains of Venezuelan encephalitis virus killed nude mice faster than normal mice after subcutaneous inoculation. Yet concentrations and durations of virus in bloods and brains were not consistently different between nude and normal mice. There were perivascular monocytes in brains and slight architectural alterations of spleens and lymph nodes. Concentrations of spleen cells producing antibodies hemolytic for sheep erythrocytes 4 days after inoculation with erythrocytes were depressed in nude and normal mice by infection with virulent strains.
Surface Structures of
Escherichia coli
That Produce Diarrhea by a Variety of Enteropathic Mechanisms
Authors: O'Hanley Peter D. , Cantey J. Robert
Published: January 2020

Strains of
Escherichia coli
, mostly of human origin, were obtained from several different investigators who had isolated them from patients with diarrhea from many different parts of the world. The mechanisms by which these
E. coli
were thought to have caused diarrhea included: (i) synthesis of labile, stable, or
Shigella dysenteriae
-like enterotoxins; (ii) invasion of the intestinal mucosa; and (iii) unknown. Each strain was carefully examined for pili or flagella to correlate the presence or absence of such surface structures with a particular mechanism of diarrhea. The presence of pili was determined by colony morphology on minimal media, pellicle formation in static broth culture, and transmission electron microscopy. The pili were categorized as type 1 if the bacteria fermented rhamnose and if pellicle formation was inhibited by α-methyl-
d
-mannoside. The presence of flagella was confirmed in motility media and by transmission electron microscopy. Six invasive
E. coli
strains lacked pili and flagella. Ten
E. coli
strains that synthesized enterotoxins or produced diarrhea by an unknown mechanism were piliated (seven with type 1 pili), and all but one had flagella. Pili and flagella seem to be associated with strains of
E. coli
that produce diarrhea by enterotoxin synthesis or unknown mechanisms. Strains that produce diarrhea by mucosal invasion lack both types of surface structures.
Glycoproteins of natural origin with an affinity for hepatitis B surface antigen
Authors: Millman I , McMichael J C
Published: January 2020

Sera from certain animal species contain a substance(s) which binds hepatitis B surface antigen. The hepatitis B binding substance found in animals is not antibody, but appears to be a glycoprotein which reacted with antigen-coated beads and produced a "false positive" test for antibody. This glycoprotein could be selectively and quantitatively removed by reaction with purified hepatitis B surface antigen and centrifugation. Pili fractions isolated from Neisseria gonorrhoeae and Escherichia coli bound to hepatitis B surface antigen and produced false positive anti-hepatitis B surface antigen reactions. Mouse anti-bovine hepatitis B binding substance and rabbit anti-E. coli pili were capable of neutralizing bovine hepatitis B binding substance.
Role of Nonagglutinating Antibody in the Protracted Immunity of Vaccinated Mice to
Pseudomonas aeruginosa
Infection
Authors: Moody M. R. , Kessel R. W. I. , Young V. M. , Fiset P.
Published: January 2020

Effective immunization against infection with
Pseudomonas aeruginosa
is difficult to evaluate because agglutinin levels decline rapidly. Because fractionation of hyperimmune sera often yields more specific antibody than can be accounted for by direct agglutination tests, an immunoglobulin-specific assay based on antiglobulin augmentation was used to characterize antibody responses of C3H/HeJ mice vaccinated with
P. aeruginosa
type 2 lipopolysaccharide. Nonagglutinating antibodies, initially detected at 2 weeks post-primary vaccination, were predominantly immunoglobulin G after 5 weeks, and they remained elevated at levels usually 32-fold higher than the direct titer throughout the 4-month study period. The sequential production of immunoglobulin M, then immunoglobulin G, followed that found in orthodox immunological responses. Sera that contained nonagglutinating antibodies but not direct agglutinins (14 to 16 weeks) enhanced phagocytosis of
P. aeruginosa
type 2 by macrophages from unimmunized mice and passively immunized mice against lethal challenge doses; bactericidal activity of these sera was not demonstrated in the presence or absence of complement. When challenged with 1, 10, and 100 50% lethal doses at 16 weeks, survival rates of actively immunized mice were significantly higher than those of unvaccinated mice (
P
< 0.001). Thus, at a time when no direct agglutinins were detectable, the augmented system detected nonagglutinating antibodies that could confer protracted resistance in vaccinated mice to pseudomonas infection.
IgG1 and IgG2 immunoglobulins to Bacteroides (Fusiformis) nodosus protease in infected and immunized sheep
Authors: Merritt G C , Egerton J R
Published: January 2020

Sheep experimentally infected with foot rot developed antibodies that neutralized the proteolytic activity of Bacteroides nodosus culture filtrates in vitro. Similar antibody activity developed in sheep vaccinated against foot rot. In both cases the antibody was initially only associated with the IgG2 fraction of serum, but with time there was an increase in the proportion associated with IgG1. A subsidiary protein peak devoid of antiprotease activity was observed in elution profiles of affected and vaccinated sheep.
Plasmid Carriage and the Serum Sensitivity of Enterobacteria
Authors: Taylor Peter W. , Hughes Colin
Published: January 2020

The carriage of a range of plasmids by rough, serum-sensitive laboratory strains of
Escherichia coli
made no difference to their reactivity in human serum as determined by two methods. Plasmid-carrying enterobacteria isolated from polluted river water gave a variety of responses to serum. Smooth
E. coli
river isolate C8 was killed by serum but only after a delay of 1 h, and curing of antibiotic resistance and colicin determinants from this strain led to a small but significant increase in serum sensitivity. Plasmids from eight strains were transferred by conjugation to a cured derivative of C8 (C8
−
Nal
R
), and in six cases a significant increase in the serum resistance of the progeny was observed. Plasmid-mediated enhancement of resistance was particularly marked with plasmids R1 and NR1, and a round of replication mutant of NR1 conferred greater resistance than did the normal R factor. However, R1 and NR1 were unable to modify the serum response of a cured strain (P21
−
Nal
R
) derived from promptly serum-sensitive isolate P21. These findings suggest that lipopolysaccharide O-side chains, the cell surface components responsible for the delay in serum killing, are essential for the expression of plasmid factors that modify sensitivity to serum. Examination of K(A)
−
variants of two isolates indicated that the K(A) antigen has only a marginal effect on the serum response.
Protection against Marek's disease-derived tumor transplants by the nononcogenic SB-1 strain of Marek's disease virus
Authors: Schat K A , Calnek B W
Published: January 2020

A series of experiments was conducted to study the in vivo protection against Marek's disease-derived tumor transplants by the nononcogenic SB-1 strain of Marek's disease virus. Intact, embryonally bursectomized (Bx), thymectomized (Tx), or cyclophosphamide (Cy)-treated chickens of four genetic lines were vaccinated with live or inactivated SB-1. JMV, a non-virus-producing transplant, and GA/Tr-1 and MDT-198, two virus-producing transplants were used for challenge. Optimal protection against JMV was present 7 days postvaccination, but there was significant protection even when SB-1 and JMV were administered together. Protection was abolished by an increase in the number of tumor cells used for challenge or by combined Tx and Cy treatment. Inactivated SB-1-infected cells were unable to induce protection against JMV challenge. Protection was also present against challenge with GA/Tr-1, but not against MDT-198, except in vaccinated, Bx chickens. It was concluded that protection against JMV was T-cell dependent and required the induction of neo-antigens not present in an inactivated SB-1 cellular preparation. The absence of protection in intact chickens against MDT-198 could not be explained.
Lung lysophospholipase activity in specific-pathogen-free rats infected with Pasteurella pneumotropica or Mycoplasma pulmonis
Authors: Laubach H E , Kocan A A , Sartain K E
Published: January 2020

The effects of Pasteurella pneumotropica and Mycoplasma pulmonis infections in specific-pathogen-free rats were studied to determine whether or not bacterial infections could cause an increase in rat lung lysophospholipase activity and/or changes in bone marrow eosinophil levels. Lung lysophospholipase activity levels of M. pulmonis-infected rats were elevated with increasing infection dosages, but enzyme levels were not accompanied by a lung tissue eosinophilia or an increase in bone marrow eosinophils. Rats infected with P. pneumotropica showed neither an increased lung lysophospholipase activity level nor an increased tissue or bone marrow eosinophilia.
Effect of immunization on susceptibility to experimental Streptococcus mutans and Streptococcus sanguis endocarditis
Authors: Durack D T , Gilliland B C , Petersdorf R G
Published: January 2020

It has been asserted that humoral immunity is an important potentiating factor in pathogenesis of infective endocarditis, in that prior immunization to certain bacteria may predispose the host to endocarditis caused by those organisms. If so, possible future vaccination of humans with streptococcal antigens for the prevention of dental caries might increase the susceptibility of the population to streptococcal endocarditis. To examine this hypothesis further, we immunized rabbits with killed Streptococcus sanguis or Streptococcus mutans. After complement-fixing antibody had developed, the rabbits were tested for susceptibility to experimental infective endocarditis. Rabbits with high titers of complement-fixing antibody to the infecting organism developed streptococcal endocarditis less often (13%) than animals with lower titers (69%; P less than 0.0002). These findings do not support the hypothesis that pre-immunization predisposes to infective endocarditis and lend no credence to the concept that vaccination of human subjects against dental caries might increase their susceptibility to streptococcal endocarditis. On the contrary, the results of these experiments indicate that specific antibody can confer relative immunity to infective endocarditis.
Age-dependent variations in polymorphonuclear leukocyte chemiluminescence
Authors: Van Epps D E , Goodwin J S , Murphy S
Published: January 2020

Polymorphonuclear leukocytes from 46 adults (age 18 to 35), 19 adults (age 70 to 91), 10 children (age 1 to 3), and 22 neonates (cord blood samples) were tested for their chemiluminescence response to opsonized zymosan. Results indicated that both cord blood leukocytes and those from individuals over 70 were significantly lower (P less than 0.05) in their chemiluminescence response. Furthermore, when the latter group was divided into two subsets, one containing subjects over 80 years of age and the other containing subjects between 70 and 80 years of age, those over 80 showed a chemiluminescence response significantly lower (P less than 0.05) than those between 70 and 80. The kinetics of the chemiluminescence response was similar with all samples except the neonatal cells, where the response appeared to peak and subside more slowly. These data demonstrate that polymorphonuclear leukocyte chemiluminescence is depressed in the very young and the very old.
Comparative study of American cutaneous leishmaniasis and diffuse cutaneous leishmaniasis in two strains of inbred mice
Authors: Pérez H , Arredondo B , González M
Published: January 2020

Two Leishmania strains, AZV (isolated from a typical case of American cutaneous leishmaniasis) and AMP (from a case of diffuse cutaneous leishmaniasis), were studied in C57BL/6 and BALB/c mice. After infection with 10(4) amastigotes of either strain, C57BL/6 mice developed self-resolving lesions lasting 20 to 23 weeks and showed both delayed hypersensitivity response to leishmanial antigen and specific agglutinating antibodies. On the other hand, BALB/c mice infected with 10(4) AZV or AMP amastigotes developed chronic, large, ulcerated lesions and showed impaired cellular and humoral responses to the parasite. When BALB/c and C57BL/6 mice received 10(2) AMP amastigotes, patterns of infection were similar to those observed after inoculation of 10(4) amastigotes. In vitro studies revealed that spleen cells from AZV- or AMP-infected C57BL/6 mice showed an increased DNA-synthetic response to leishmanial antigen, concanavalin A, and phytohemagglutinin. Spleen cells from AZV- or AMP-infected BALB/c mice showed an increased response to concanavalin A and diminished responses to leishmanial antigen, phytohemagglutinin, and lipopolysaccharide.
Prophylaxis of Bordetella bronchiseptica infection in guinea pigs by intranasal vaccination with live strain ts-S34
Authors: Shimizu T
Published: January 2020

The temperature-sensitive mutant strain, ts-S34, of Bordetella bronchiseptica, which cannot grow at or above the temperature 34 degrees C, has been studied in guinea pigs. The strain grew to moderate numbers in the nasal turbinates but did not grow in the lungs. Guinea pigs given strain ts-S34 developed moderate levels of serum antibody. This strain also induced very high resistance to subsequent intranasal challenge with 4,000X the 50% lethal dose of virulent strain S1 of B. bronchiseptica. In these studies, it appeared that the ts-S34 strain had favorable properties for potential use as a live attenuated vaccine.
Studies on gonococcus infection. XVI. Purification of Neisseria gonorrhoeae immunoglobulin A1 protease
Authors: Blake M S , Swanson J
Published: January 2020

A protease which cleaves human immunoglobulin A1 (IgA1) has been purified from broth cultures of Neisseria gonorrhoeae. This IgA1 protease is produced by pilated and nonpilated gonococci throughout their growth cycles. A combination of ammonium sulfate precipitation, column chromatography, and either isoelectric focusing or affinity chromatography was utilized to obtain an enzyme preparation that showed approximately 3,800-fold purification and exhibited two bands (65,000 and 70,000 daltons) by analytical polyacrylamide electrophoresis in the presence of sodium dodecyl sulfate and reducing conditions. IgA1 protease activity is dependent on divalent cations and is heat labile. Detection and quantitation of IgA protease activity utilized an assay in which [125I]IgA1 is incubated with protease preparations and the cleavage products are analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis.
Bordetella pertussis does not induce beta-adrenergic blockade
Authors: Hewlett E , Spiegel A , Wolff J , Aurbach G , Manclark C R
Published: January 2020

Bordetella pertussis organisms induce histamine sensitivity and diminish the normal hyperglycemic response to epinephrine in experimental animals. These effects have been attributed to beta-adrenergic blockade. However, under conditions in which the decrease in epinephrine-induced hyperglycemia after B. pertussis administration was demonstrable, there was no change in rat reticulocyte beta-adrenergic receptor number or affinity measured by iodohydroxybenzylpindolol binding or in isoproterenol-stimulated adenylate cyclase activity. Therefore, there was no generalized beta-adrenergic blockade induced by B. pertussis. The observed effects can be explained by the hypersecretion of insulin resulting from B. pertussis administration.
Brucella antigen preparations for in vitro lymphocyte immunostimulation assays in bovine brucellosis
Authors: Kaneene J M , Anderson R K , Johnson D W , Muscoplat C C
Published: January 2020

Three Brucella antigen preparations, Brucella abortus soluble antigen, B. abortus strain 45/20 enriched protein antigen, and B. melitensis enriched protein antigen, were compared in terms of their ability to induce specific in vitro lymphocyte immunostimulation responses. Lymphocytes were prepared from peripheral blood of cattle with different exposure experiences to B. abortus organisms. Lymphocytes were processed by the Ficoll-diatrizoate technique, and results were assayed for [3H]tymidine incorporation into DNA by liquid scintillation spectrometry. The three Brucella antigen preparations were compared both at the optimal concentrations of protein and on an equal-dry-weight basis. The results were evaluated in terms of specific lymphocyte immunostimulation responses induced by each preparation and the degree of correlation with infection. B. abortus soluble antigen-induced lymphocyte immunostimulation response correlated best with infection status followed by B. abortus 45/20 and B. melitensis enriched protein antigens. The implications of these findings are discussed and a hypothesis is proposed.
Stimulation of polymorphonuclear leukocyte bactericidal activity by supernatants of activated human mononuclear cells
Authors: Cross A S , Lowell G H
Published: January 2020

Supernatants of phytohemagglutinin-activated human mononuclear cells stimulated polymorphonuclear leukocyte (PMN) activity against the gram-negative organism Serratia marcescens. In the absence of serum opsonins, when control PMN could not impede bacterial growth, stimulated PMN averaged more than 0.6-log kill of the original bacterial inoculum. In the presence of optimal amounts of serum opsonins, when control PMN were significantly bactericidal, stimulated PMN killed, on the average, at least 0.6 log more of bacteria. Stimulation was not found when PMN were preincubated with supernatants for 1 h or less. The data strongly suggested that the action of the PMN stimulating factor was independent of and different from classically described serum opsonins. PMN stimulating activity may be an additional lymphokine-mediated immune defense mechanism enabling hosts to kill invading microorganisms.
Host defenses in murine malaria: induction of a protracted state of immunity with a formalin-killed Plasmodium berghei blood parasite vaccine
Authors: Murphy J R , Lefford M J
Published: January 2020

Random-bred mice were immunized with a nonliving antigen prepared from mixed-blood forms of Plasmodium berghei, strain NYU-2, in combination with Corynebacterium parvum and/or living BCG. A high proportion of intravenously immunized mice survived virulent challenge, but subcutaneous vaccination was less effective. Vaccinated mice developed a patent infection after challenge similar to that observed in normal controls. However, between days 12 to 20 postchallenge, infections in some vaccinated mice became subpatent, whereas infections in all normal controls progressed until death. The incidence of recrudescent infection was low and, eventually, a state of sterile immunity was established. The capacity of vaccinated mice to withstand P. berghei challenge was sustained at a fairly stable level for the 6-month period of observation. Mice that had survived a primary infection with P. berghei almost completely suppressed a second and larger challenge with the same organism.
Mechanisms of immunity in typhus infection: some characteristics of intradermal Rickettsia mooseri infection in normal and immune guinea pigs
Authors: Murphy J R , Wisseman C L , Fiset P
Published: January 2020

Rickettsia mooseri infection in skin at sites of intradermal inoculation was studied in nonimmune and immune guinea pigs with respect to dynamics of infection, localization of rickettsiae within tissues, and gross and microscopic pathology. Intradermal inoculation of R. mooseri into nonimmune guinea pigs resulted in gross lesions which, in magnitude, were directly related to the number of rickettsiae inoculated. The lesions progressively enlarged through 3 or 4 days and remained enlarged through at least 7 days. Histological examination revealed an early acute inflammation which progressed to a predominantly monocyte-macrophage inflammation and subsequently condensed into lymphocyte-containing granulomatous foci. Rickettsiae in the skin at sites of inoculation increased in numbers from 6 h through 3 days, in parallel with the increasing diffuse monocyte-macrophage inflammatory response, and then declined markedly on days 4 or 5 as ganulomatous foci appeared. Some rickettsiae, however, persisted through at least day 7. Fluorescent-antibody studies suggested that R. mooseri infected only a subset of cells available, i.e., cells associated with the microvascular system. Dissemination of infection was demonstrated by the presence of rickettsiae in the skin at sites distant from the point of inoculation. Immune guinea pigs, made immune by intradermal infection with R. mooseri 12 days before intradermal challenge, displayed an accelerated response. The lesions were maximal by 24 to 48 h and subsequently regressed. The inflammatory response of immune guinea pigs was a greater magnitude than the response of similarly challenged nonimmune guinea pigs, and the respose from acute inflammation through the formation of granulomatous lesions was accelerated. The number of rickettsiae in the skin of immune guinea pigs declined steadily from the time of inoculation, until no rickettsiae were recovered on or after day 3. Furthermore, dissemination of rickettsiae to sites in skin distant from the site of inoculation was not demonstrable. The results are discussed in terms of pathogenesis and of immunity to typhus.
Extractability of Cell Wall Polysaccharide from Lactobacilli and Streptococci by Autoclaving and by Dilute Acid
Authors: Campbell Lindy K. , Knox Kenneth W. , Wicken Anthony J.
Published: January 2020

Autoclaving cell wall of
Streptococcus mutans
Ingbritt for 15 min under the Rantz and Randall conditions released one-tenth of the total cell wall carbohydrate, whereas two-thirds was extracted after autoclaving for 180 min. The extract contained the serotype
c
-specific antigen but lacked the lipoteichoic acid component extracted when whole cells were autoclaved. Autoclaving cell wall preparations from other strains of
S. mutans
and also
Streptococcus salivarius
and
Streptococcus mitis
in 0.85% NaCl for 180 min released the major proportion of the wall polysaccharide fraction. Approximately 50 to 90% of wall carbohydrate of
Lactobacillus fermentum
and
Lactobacillus casei
was released when cell wall preparations were autoclaved in 0.85% NaCl for 180 min. For wall preparations from several strains of
S. mutans
, autoclaving for 60 min at pH 3.75 released only 39 to 62% of wall carbohydrate, whereas almost total release could be achieved with the lactobacilli. Heating
S. mutans
Ingbritt cell wall for 24 h at 60°C in 0.1 N H
2
SO
4
released only two-thirds of the wall carbohydrate; by comparison nearly all of the wall carbohydrate was released in 3 h from
L. casei
and
L. fermentum.
Autoclaving
L. casei
cell wall and purified soluble wall fractions hydrolyzed the phosphodiester bond between the polysaccharide and peptidoglycan. This was shown by the release of reactive
N
-acetylhexosamine in both cases and the presence of a phosphomonoester in the autoclaved soluble wall fractions. The results indicate that autoclaving can hydrolyze covalent linkages, and this must be considered when the Rantz and Randall procedure is used to obtain antigen preparations.
Protective immunity induced in mice by immunization with high-molecular-weight polysaccharide from Pseudomonas aeruginosa
Authors: Pier G B , Sidberry H F , Sadoff J C
Published: January 2020

A high-molecular-weight alkali-labile polysaccharide (PS) isolated from the slime of immunotype 1 Pseudomonas aeruginosa was tested for its ability to protect mice from lethal challenge with the live, homologous organism. Intraperitoneal (i.p.) injection of 10 to 25 microgram of the PS protected 60 to 70% of the mice against challenge with up to 50 50% lethal dose units. Although single immunization of mice with up to 250 microgram of PS effected protective levels of only 70%, two successive immunizations provided 100% protection. Subcutaneous and intravenous immunization with PS also provided protection to i.p. challenges with immunotype 1 P. aeruginosa, but not to i.p. challenge with immunotype 4 P. aeruginosa. Although lipopolysaccharide (LPS) was found to be more immunogenic than PS in out studies, contamination of the alkali-labile PS with LPS did not account for the protection seen. Alkali treatment (0.1 N NaOH, 37 degrees C, 2 h) of the PS destroyed its protective effectiveness, while similarly treated LPS retained its capacity for inducing immunity in mice. Adsorption and passive protection studies with sera raised to either PS or a mixture of PS and LPS indicated that antibody directed to the alkali-labile PS antigen was capable of contributing to the protection of mice against challenge with P. aeruginosa.
Soluble antigens of virulent and attenuated biotypes of Brucella abortus
Authors: Hatten B A , Brodeur R D
Published: January 2020

Several methods were used to characterize three Brucella abortus biotypes (1, 5, and 7), including the attenuated vaccine strain S-19. Chemical analysis did not reveal remarkable differences among these strains, and only minor differences were noted in elution patterns of soluble extracts subjected to column chromatography. Qualitative and quantitative differences in extract components were demonstrated, however, by polyacrylamide gel isoelectric focusing. A distinctive difference was the presence of components in extracts from one or more of the virulent biotypes that were absent in similar preparations from the attenuated strain. In addition, one component common to all virulent strains was absent in strain S-19. Results of immunodiffusion experiments employing adsorbed and unadsorbed antisera also suggested that the quantity, quality, and surface distribution of various cellular antigens differed among the biotypes studied.
Proteoglycans, proteases, chemotaxis, and aggregation of inflammatory, cells
Authors: Lynn W S , Mukherjee C
Published: January 2020

A trypsin-like protease activity present in rabbit alveolar macrophages was shown to be activated by hyaluronic acid (HA) at 10(-9) M, but not by other proteoglycans. This activation of proteases by HA was accompanied by aggregation of alveolar macrophages and by the release of chemotactic activity. This chemotactic activity was destroyed by proteases and was less active for polymorphonuclear leukocytes than for alveolar macrophages. These effects of HA appear to be sepcific for alveolar macrophages, because no similar effects of HA on human polymorphonuclear leukocytes or lymphocytes could be observed. These observations suggest that HA, which is secreted into airways, plays a specific role in the macrophage-mediated chronic inflammatory processes in the distal lung.
Importance of the intestinal inflammatory reaction in salmonella-mediated intestinal secretion
Authors: Giannella R A
Published: January 2020

The ability of Salmonella typhimurium to invade the intestinal epithelium is essential to the pathogenesis of salmonella-induced intestinal secretion. This invasion is accompanied by an intense acute inflammatory reaction. The present study tests the hypothesis that the acute inflammatory reaction may have a role in the pathogenesis of salmonella-induced secretion. Two groups of rabbits infected with S. typhimurium were studied: normal animals and animals pretreated with nitrogen mustard. Nitrogen mustard depletes the polymorphonuclear leukocyte pool and thereby prevents the formation of an acute inflammatory reaction. In vivo ligated ileal loops were constructed and infected 72 h after nitrogen mustard administration when polymorphonuclear leukocytes were undetectable. Nitrogen mustard treatment markedly inhibited salmonella-induced secretion. Ileal histology in normal animals infected with S. typhimurium revealed an intense acute inflammatory reaction, while in animals pretreated with nitrogen mustard only a rare polymorphonuclear leukocyte was seen. The antisecretory effect of nitrogen mustard was not merely a nonspecific effect since nitrogen mustard treatment did not inhibit cholera toxin-induced secretion and did not alter either ileal morphology nor the activities of various intestinal enzymes in normal animals. Nitrogen mustard also did not alter the virulence of the inoculated S. typhimurium. These data suggest that the mucosal inflammatory reaction induced by salmonella invasion may be important to the pathogenesis of the salmonella secretory process. The mechanism by which the inflammatory reaction stimulates secretion is not known.
Cell-mediated immune response to bacterial products in human tonsils and peripheral blood lymphocytes
Authors: Drucker M M , Agatsuma Y , Drucker I , Neter E , Bernstein J , Ogra P L
Published: January 2020

Lymphoproliferative responses of tonsillar tissue lymphocytes and peripheral blood lymphocytes to phytohemagglutinin and specific bacterial product antigens were studied in children undergoing tonsillectomy and adenoidectomy. Tonsillar tissue lymphocytes responded to optimal concentrations of phytohemagglutinin. Varidase, and streptolysin-O in a manner similar to peripheral blood lymphocytes. Higher base-line mitogenic activity in tonsillar lymphocytes was frequently associated with the presence of Staphylococcus aureus in the tonsils. Tonsillar tissue lymphocytes from 23% of the subjects with the highest base-line mitogenic activity manifested a decreased response to in vitro stimulation with mitogens or antigens. In subjects with such preactivated tonsillar lymphocytes, the proliferative responsiveness of blood lymphocytes to mitogen and antigens was markedly increased after tonsillectomy and adenoidectomy. These observations suggest the existence of in vitro correlates of cellular immunity to bacterial products in the mucosal surfaces. In addition, it is proposed that tonsils may possess immunosuppressive activity for peripheral blood lymphocytes, which may be related to local tonsillar infections.
Susceptibility of lymphoblastoid cells to infection with human cytomegalovirus
Authors: Tocci M J , St Jeor S C
Published: January 2020

Human lymphoblastoid cells of B- and T-cell origin were examined for their in vitro susceptibility to infection with human cytomegalovirus (CMV). Results of infectious-center assays, at virus to cell ratios of 10, indicated that in each of the lymphoblastoid cell lines tested less than 1% of the cells produced infectious virus. Under these conditions, CMV specific antigens were undetectable. Infection of lymphoblastoid cells with CMV resulted in atypical virus growth curves similar to those obtained with persistently infected human embryonic kidney cells. Although some variation existed in the relative sensitivity of lymphoblasts, cells of B (Raji, P3J-HR-1, RPMI 8226) and T (CCRF-CEM) origin were susceptible to infection with CMV. Variation in the sensitivity of lymphoblasts to CMV infection did not correlate with differences in virus adsorption or the presence of Epstein-Barr virus deoxyribonucleic acid. These studies suggest that human lymphoblastoid cells could serve as a model to examine persistent CMV infection in lymphoid cells of various origin.
Myeloperoxidase, hydrogen peroxide, chloride antimicrobial system: nitrogen-chlorine derivatives of bacterial components in bactericidal action against Escherichia coli
Authors: Thomas E L
Published: January 2020

In the presence of Escherichia coli, myeloperoxidase-catalyzed oxidation of chloride ion resulted in formation of long-lived chloramine and/or chloramide derivatives of bacterial components. The same amount of these nitrogen-chlorine (N-Cl) derivatives was obtained with either hypochlorous acid (HOCl) or the myeloperoxidase system, indicating that myeloperoxidase catalyzed the oxidation of chloride to HOCl. Identical killing was obtained with HOCl or the myeloperoxidase system. About 30 to 50% of the oxidizing equivalents of HOCl were detected as N-Cl derivatives of peptides or peptide fragments that were released from the bacteria. The apparent molecular weight distribution of the peptides decreased with increasing amounts of HOCl, suggesting that peptides were fragmented by oxidative cleavage of chloramide derivatives of peptide bonds. The remaining 50 to 70% of the oxidizing equivalents of HOCl were rapidly consumed in peptide bond cleavage or the oxidation of other bacterial components. There was a close correspondence between the oxidation of bacterial sulfhydryls and bactericidal action. The N-Cl derivatives were lost and the oxidation of bacterial sulfhydryls increased over a period of several h at 37 degrees C. These changes were accompanied by increased killing. The increase in sulfhydryl oxidation and killing could be prevented by washing the bacteria to remove the N-Cl derivatives. Therefore, the N-Cl derivatives could oxidize bacterial components long after the myeloperoxidase-catalyzed oxidation of chloride was complete.
Protective Effect of Active Immunization with Purified
Escherichia coli
Heat-Labile Enterotoxin in Rats
Authors: Klipstein Frederick A. , Engert Richard F.
Published: January 2020

The protective effect of active immunization by different routes with a purified preparation of the polymyxin-release form of
Escherichia coli
heat-labile toxin was evaluated in rats. Immunized animals were challenged by placing toxin into ligated ileal loops at dosages which produced either 50% or the maximum secretory response in unimmunized rats. Immunization exclusively by the parenteral route yielded significant protection. Rats were also protected when parenteral priming was followed by boosting given either directly into the duodenum or perorally 2 h after intragastric cimetidine, but not when the peroral boosts were given with bicarbonate. Immunization administered entirely by the peroral route with cimetidine yielded protection but only when the immunizing dosage was fivefold greater than that found effective in the parenteral-peroral approach. Rats immunized exclusively by the parenteral route and those boosted perorally with cimetidine were also tested, and found to be protected, against challenge with viable organisms of strains that produce either heat-labile toxin alone or both heat-labile and heat-stable toxin, but they were not protected against a strain which produces just heat-stable toxin. Geometric mean serum antibody titers were increased by 16-fold or more over control values in those groups of rats in which protection was achieved, with the exception of those immunized exclusively by the peroral route. These observations demonstrate that (i) active immunization with purified
E. coli
heat-labile toxin results in significant protection against both this toxin as well as viable organisms which produce it, but not against viable strains which produce heat-stable toxin only, and (ii) concomitant ablation of gastric secretion by the use of cimetidine renders the peroral route of immunization effective. They suggest that prophylactic immunization against diarrheal disease caused by heat-labile toxin-producing strains of
E. coli
may be feasible in humans.
Response of Congenitally Athymic (Nude) and Phenotypically Normal Mice to
Cryptococcus neoformans
Infection
Authors: Cauley Larry K. , Murphy Juneann W.
Published: January 2020

A
Cryptococcus neoformans
infection in congenitally athymic (nude) mice and phenotypically normal heterozygote BALB/c mice was used to determine how T lymphocyte-deficient mice compared with normal mice in restricting proliferation of
C. neoformans
and to determine whether a correlation exists between delayed-type hypersensitivity and resistance to
C. neoformans
. Although nude mice displayed the ability to maintain cryptococcal population levels lower than did the phenotypically normal animals during the first 14 days of infection, the resistance was not sufficient to control the infection during the remainder of the 35-day experimental period. Heterozygote mice began to demonstrate positive delayed-type hypersensitivity responses by day 14 postinfection; however, nude mice were unable to mount delayed-type hypersensitivity responses. The appearance of the delayed-type hypersensitivity response in the heterozygote mice was concomitant with the reduced rate of proliferation of
C. neoformans
observed in those animals from days 14 to 35. Because anticryptococcal antibody titers and cryptococcal antigen levels were equivalent in both groups of mice, T-lymphocyte function was considered to be responsible for the resistance observed in the heterozygote mice. The mechanism by which cryptococcal populations were reduced was not addressed; however, the mouse model system used in these studies would be an ideal tool for studying those mechanisms. Nude mice were able to produce antibodies against cryptococcal cells, indicating that at least one component of
C. neoformans
is a T-independent antigen. The antibody response was predominantly immunoglobulin M in nude and heterozygote mice. Cryptococcal antigen levels were extremely high in both groups of animals and appeared to increase as
C. neoformans
cell numbers increased.
Cytotoxic enterotoxin produced by Aeromonas hydrophila: relationship of toxigenic isolates to diarrheal disease
Authors: Cumberbatch N , Gurwith M J , Langston C , Sack R B , Brunton J L
Published: January 2020

Ninety-six Aeromonas hydrophila isolates were tested for cytotoxin and hemolysin production. Sixty-six (69%) of the isolates were both cytotoxic and hemolytic, whereas the rest produced neither cytotoxin nor hemolysin. No evidence of a separate cytotonic activity could be found in any of the isolates. Cytotoxin activity correlated with enterotoxic activity. Of four cytotoxin-producing strains tested in the isolated rabbit ileal loop, three were definitely positive and one was borderline, whereas two nontoxigenic strains were negative. Cytotoxin activity appeared to be a stable property and could not be assoicated with any common identified plasmid; only 10 of 21 cytotoxin-producing strains could be shown to have any plasmid by agarose gel electrophoresis. Cytotoxin production correlated with a positive lysine decarboxylase phenotype (98%) or a positive Voges-Proskauer phenotype (94%), compared to 27% lysine decarboxylase-positive and 23% Voges-Proskauer-positive, cytotoxin-negative isolates (P less than 0.001 for both). In fecal samples, cytotoxin production correlated with diarrheal disease; of 40 diarrheal isolates, 32 (80%) were toxigenic compared to 9 (41%) of 22 nondiarrheal isolates (P = 0.004). It appears that A. hydrophila can be a cause of diarrhea and that this enteropathogenic potential is mediated by a cytotoxic enterotoxin.
Experimental hematogenous Candida endophthalmitis: diagnostic approaches
Authors: Henderson D K , Edwards J E , Ishida K , Guze L B
Published: January 2020

Anterior chamber aspiration and vitreous aspiration were evaluated as diagnostic procedures for establishing a specific microbiological diagnosis in the rabbit model of hematogenous Candida endophthalmitis. Vitreous aspiration was the most successful procedure, confirming the diagnosis of hematogenous Candida endophthalmitis in 62% of eyes with documented intraocular infection. When animals with only the most severe clinical endophthalmitis were considered, vitreous aspiration confirmed the diagnosis in 89% of eyes evaluated. Vitreous aspiration correlated well with the extent of clinical endophthalmitis, as well as with postmortem, whole-vitreous cultures. Gram staining of the aspirate was additive to culture results in confirming the diagnosis. Anterior chamber aspiration was positive in only 1 of 58 eyes evaluated (1.7%). Additionally, muscle biospy was evaluated in this study as a tool for establishing a microbiological diagnosis in the rabbit model of disseminated candidiasis. Only 2 of 131 biospy specimens contained detectable Candida. Although vitreous aspiration may be associated with ocular complications, in certain clinical settings this procedure may be valuable in establishing the definitive microbiological diagnosis of hematogenous Candida endophthalmitis.
Immunogenicity of Bacteroides isolated from mice: relationship between immunogenicity and cell wall antigens
Authors: Yasui H , Yasutake N , Ohwaki M
Published: January 2020

Three different strains of Bacteroides were isolated from feces and cecal contents of mice. The immunogenicity of the strains was determined by measuring the serum agglutinin titers after intraperitoneal antigen injection. There were marked differences in quantity and quality of produced antibodies among the three strains. One strain (2-2) induced low antibody titers in both the primary and secondary responses, and a significant 2-mercaptoethanol (2-ME)-resistant antibody production occurred. Another strain (Y) induced low antibody titers in the primary response and high titers in the secondary response, but 2-ME-resistant antibody production did not occur. The third strain (2-4) induced very high antibody titers in both the responses, and a large amount of 2-ME-resistant antibody production occurred. Further, heat-ethanol-treated strain Y induced only immunoglobulin M antibody, but periodate-treated strain Y induced no antibody. Heat-ethanol- or periodate-treated strain 2-4 induced immunoglobulin M or G antibody, respectively. These observations suggest that the surface antigens of the two strains are distinctly different: the antigen of strain Y would be mostly O-antigen, whereas those of strain 2-4 would be O-antigen and protein moieties.
Inhibitory effect of Pseudomonas aeruginosa on the phagocytic and killing activity of rabbit polymorphonuclear leukocytes: mechanisms of action of a polymorphonuclear leukocyte inhibitor
Authors: Nonoyama S , Kojo H , Mine Y , Nishida M , Goto S , Kuwahara S
Published: January 2020

The polymorphonuclear leukocyte (PMN) inhibitor isolated from a strain of Pseudomonas aeruginosa which is resistant to the phagocytic and killing activities of rabbit PMN inhibited migration of PMN and engulfment of latex particles by PMN. In studies of the bactericidal metabolism of PMN, the PMN inhibitor did not inhibit the intracellular activity and extracellular release of lysosomal enzymes. However, the PMN inhibitor caused a decrease of Nitro Blue Tetrazolium reduction. The PMN inhibitor had a cytotoxic effect on PMN and inhibited [14C]tyrosine uptake in intact PMN inhibitor had no inhibitory effect on protein synthesis in cell extracts.
Molecular approach to the epidemiology of swine vesicular disease: correlation of variation in the virus structural polypeptides with serological properties
Authors: Harris T J , Underwood B O , Knowles N J , Crowther J R , Brown F
Published: January 2020

Variation has been observed in the structural polypeptides of swine vesicular disease viruses isolated from the United Kingdom and Hong Kong. Despite the limited number of isolates examined, several distinct polypeptide patterns were obtained when the virus structural proteins were examined by polyacrylamide gel electrophoresis. Isolates from outbreaks in the United Kingdom which were known to be connected gave the same polypeptide pattern, whereas viruses with different polypeptide patterns could not be traced to a common source. The different polypeptide patterns were obtained consistently and were not altered by passage of the virus in tissue culture. In general, isolates with identical polypeptide patterns could not be distinguished by neutralization or antibody blocking tests or by competition radioimmunoassays. However, isolates with different polypeptide patterns could be differentiated by antibody blocking tests or radioimmunoassay. The correlation between the serological tests and the polyacrylamide gel electrophoresis analyses illustrates the value of analyzing structural polypeptides in the epidemiological study of swine vesicular disease.