bluuebunny/crossref_metadata_2025 huggingface dataset:
Preliminary demonstration of human tuberculoimmunity in vitro
Authors: Crowle A J , May M
Published: January 2020

In this paper a method for studying human tuberculoimmunity in vitro is described. Results from its use support an explanation for human tuberculoimmunity that is like that for mouse tuberculoimmunity: that immune lymphocytes are stimulated by being cultured with immunizing antigen to make a lymphokine which enables syngeneic macrophages to kill intracellular tubercle bacilli. This method uses antigen-responding lymphocytes and effector monocytes taken in the same original 20-ml sample of venous blood. These cells are cultured separately, the lymphocytes for 72 h with antigen to make immune lymphokine and the monocytes for 7 days to become macrophages. The macrophages are then infected with attenuated or virulent tubercle bacilli and cultured for 7 days more in medium with or without the immune lymphokine. Without it they are unable to control intracellular replication of the bacilli, whereas with it they do. This lymphokine was produced only by lymphocytes of immune subjects, of whom there were three kinds: tuberculin positive naturally immunized, Mycobacterium bovis BCG immunized, and trypsin-extracted bacillary antigen immunized. This method for detecting human tuberculoimmunity in vitro should be useful for comparing experimental vaccines and for studying cellular and molecular mechanisms of human tuberculoimmunity under better controlled conditions than hitherto have been possible.
Production of lesions in gnotobiotic mice by inoculation with Treponema hyodysenteriae
Authors: Joens L A , Robinson I M , Glock R D , Matthews P J
Published: January 2020

Treponema hyodysenteriae was established in the ceca of gnotobiotic mice in the absence of other organisms. Superficial mucosal lesions characteristic of swine dysentery were present in the ceca of mice inoculated with T. hyodysenteriae in combination with viable Bacteroides vulgatus. Deep crypt necrosis was detected in the ceca of mice inoculated with T. hyodysenteriae alone.
Use of cycloheximide to study independent lipid metabolism of Chlamydia trachomatis cultivated in mouse L cells grown in serum-free medium
Authors: Reed S I , Anderson L E , Jenkin H M
Published: January 2020

A system for measuring chlamydial lipid synthesis was developed with mouse L cells grown in serum-free modified Waymouth 752/l medium in a shaker culture. Host lipid synthesis was reduced approximately 90% when cells were incubated for 24 h in medium containing cycloheximide (2 micrograms/ml). Lipid metabolism was monitored by measuring the incorporation of [3H]isoleucine into the total lipid of normal and infected cells. The results suggested that lipid synthesis of Chlamydia trachomatis lymphogranuloma venereum (LGV-404L) was not inhibited by cycloheximide treatment when the chlamydiae were grown in L cells, whereas host lipid synthesis was inhibited. Chlamydial lipid metabolism began about 6 to 12 h after infection when the noninfectious reticulate body was found and continually increased until the beginning of the appearance of intracellular infectious elementary bodies at 24 to 30 h.
Course of coccidioidomycosis in intratracheally infected guinea pigs
Authors: Cox R A , Pavey E F , Mead C G
Published: January 2020

Two hundred Hartley-inbred guinea pigs were infected intratracheally with 50 viable arthrospores of Coccidioides immitis. At weeks 1 through 10 postinfection, groups of 20 guinea pigs were assayed for skin test, macrophage migration inhibitory factor (MIF), and lymphocyte transformation (LT) responses to coccidioidin. Forty-eight hours after skin testing and just before MIF and LT assays, blood was obtained for complement-fixing (CF) antibody titers and the animals were autopsied to assess the extent of fungal dissemination. Immunological assays established that skin tests and MIF responses converted within 3 weeks of infection. LT responses were not demonstrable until week 5. Dissemination of C. immitis to the liver or spleen was an early event, with 21% of guinea pigs positive by week 2 and 70% positive by week 5. CF antibody titers were demonstrable at week 5, increased logarithmically through week 7, then increased at a slower rate thereafter. Concomitant with the decreased rate of antibody production, guinea pigs began to clear C. immitis from their extrapulmonary tissues. Skin test responses peaked at 6 weeks postinfection when CF antibody titers were less than or equal to 1:16 and then plateaued with increased CF titers. Although this overall immunological profile is consistent with the disease in humans, there was not a direct correlation between CF antibody titer and dissemination to the liver or spleen, nor was there an inverse correlation between CF antibody titers and skin test or MIF responses. Rather, CF antibody titers and cell-mediated immune responses were equally demonstrable in guinea pigs with disseminated or nondisseminated disease.
Comparisons of mycelia- and spherule-derived antigens in cellular immune assays of Coccidioides immitis-infected guinea pigs
Authors: Cox R A , Mead C G , Pavey E F
Published: January 2020

The biological activities of four Coccidioides antigens were compared in skin test, macrophage migration inhibitory factor (MIF), and lymphocyte transformation (LT) assays fo 137 Coccidioides-infected and 20 noninfected guinea pigs. Antigens included: C-ASWS-M, the alkali-soluble, water-soluble cell wall extract from mycelia of C. immitis; C-ASWS-S, the alkali-soluble, water-soluble cell wall extract from spherules; CDN-TS, a toluene-induced lysate of C. immitis mycelia; and spherulin, an autolysate obtained from spherules. CDN-TS proved significantly more reactive (P less than 0.0001) in skin tests, eliciting a mean induration of 11.6 mm as compared with indurations of 6.6, 6.4, and 6.1 mm obtained with C-ASWS-S spherulin, and C-ASWS-M, respectively. CDN-TS, C-ASWS-S, and spherulin were equally reactive in MIF assays and elicited migration inhibitions of 31.8, 30.8, and 30.7%. C-ASWS-M was significantly less reactive (P less than 0.001), with a mean response of 23.5%. The highest level of activity in LT assays was obtained with C-ASWS-S with a mean response of 5,636 delta cpm as compared with responses of 3,624, 3,439, and 3,580 delta cpm with CDN-TS, spherulin, and C-ASWS-M, respectively (P less than 0.01). All antigens were effective in distinguishing responses of infected versus noninfected guinea pigs.
Staphylococcal scarlet fever: role of pyrogenic exotoxins
Authors: Schlievert P M
Published: January 2020

Staphylococcal pyrogenic exotoxin (PE) types A and B were tested for their role in production of a scarlatiniform rash. The PEs elicited minimal skin reactions after intracutaneous injection into animals not presensitized to the toxins. In contrast, erythematous injection into animals not presensitized to the toxins. In contrast, erythematous and edematous rashes were produced after administration of either PE to animals presensitized to homologous toxin. After 3 to 4 days, the erythematous areas showed membranous desquamation. Staphylococcal PEs also enhanced delayed and Arthus hypersensitivity skin reactions developed against unrelated proteins; the reactions subsequently desquamated. In addition, animals previously sensitized to either staphylococcal PE type developed scarlatiniform rashes after challenged with heterologous staphylococcal or any group A streptococcal PE. The data suggest that staphylococcal PEs produce scarlet fever-like rashes comparable to group A streptococcal PEs and that all PE types contain a common core moiety against which delayed hypersensitivity may be developed.
Detection of antirotavirus immunoglobulins A, G, and M in swine colostrum, milk, and feces by enzyme-linked immunosorbent assay
Authors: Corthier G , Franz J
Published: January 2020

An enzyme-linked immunosorbent assay was developed to allow direct detection of class-specific antirotavirus antibodies. In colostrum and in milk, antirotavirus antibodies were found in the three immunoglobulin classes. Antirotavirus immunoglobulins G and M were predominant in colostrum, whereas antirotavirus immunoglobulin A was predominant in milk and feces.
Immunogenic glycoproteins of laboratory and vaccine strains of Varicella-Zoster virus
Authors: Grose C , Edmond B J , Friedrichs W E
Published: January 2020

High-titered antisera were prepared in guinea pigs and rabbits against two strains of varicella-zoster virus (VZV): VZV-32, a low-passage laboratory strain, and VZV-Oka, a vaccine strain attenuated by passage in both human and guinea pig embryo cells. When the animal VZV-immune sera, as well as a human zoster serum, were used to precipitate radiolabeled glycoproteins from VZV-infected cells and the immune precipitates were analyzed by polyacrylamide gel electrophoresis and fluorography, it was observed that cell cultures infected with either strain had similar electrophoretic profiles containing major glycoproteins of approximate molecular weights 62,000, 98,000, and 118,000. A prominent high-molecular-weight (approximately 150,000) nonglycosylated polypeptide was identified in both strains also. These determinants were demonstrable by both indirect (staphylococcal protein A-antibody adsorbent) and direct immunoprecipitation, as long as VZV-immune sera with an antibody titer greater than or equal to 1:128 were used. Further analysis of individual caviid VZV antisera demonstrated some heterogeneity which appeared to be related to the method of immunization rather than the level of virus-specific antibody. VZV extracts emulsified with complete Freund adjuvant elicited an antibody response to all major immunogenic viral glycoproteins, whereas guinea pigs inoculated with virus alone during the primary immunization initially produced VZV antibody which failed to precipitate the highest-molecular-weight glycoprotein (gp118). Thus, Freund-type adjuvants promoted the maturation of the humoral immune response after VZV immunization in outbred guinea pigs.
Protective immunity against murine candidiasis elicited by Candida albicans ribosomal fractions
Authors: Levy R , Segal E , Eylan E
Published: January 2020

Candida albicans ribosomes were prepared from mechanically disrupted cells through differential centrifugation and purification in a sucrose-ammonium sulfate solution. The ribosomes were analyzed chemically and physically and exhibited characteristics of eucaryotic ribosomes (78S). ICR female mice were immunized with two subcutaneous inoculations, 2 weeks apart, of 100 microgram of ribosomes (expressed as ribosomal protein). Immunized mice were challenged either intraperitoneally or intravenously with a lethal dose of live C. albicans cells. The 31-day survival rate of immunized mice challenged intraperitoneally was 64% (mean value) versus 27% in controls; in intravenously challenged mice the survival rate of the immunized animals was about 60%, with no survivors among the controls. In intravenously challenged mice, incomplete Freund adjuvant enhanced the protection elicited by the ribosomes. Protection by ribosomal immunization was obtained against challenge doses causing chronic and acute infection.
Influence of Growth Medium on Adsorption of
Streptococcus mutans, Actinomyces viscosus
, and
Actinomyces naeslundii
to Saliva-Treated Hydroxyapatite Surfaces
Authors: Peros W. J. , Gibbons R. J.
Published: January 2020

The influence of the growth medium on the ability of strains of
Streptococcus mutans, Actinomyces viscosus
and
A. naeslundii
to attach to saliva-treated hydroxyapatite (S-HA) surfaces was studied. Preliminary experiments indicated that cells of each species harvested in lag, log, and early stationary phases of growth adsorbed comparably to S-HA; thus, early stationary phase cells were used in all subsequent assays. Strains were grown in chemically defined medium (CDM), in CDM supplemented with gastric mucin or with filter-sterilized or
60
Co-irradiated saliva from human donors of blood types A, B, or O, and in Trypticase soy broth (BBL Microbiology Systems) and Todd-Hewitt broth. Adherence of
S. mutans
H12 to S-HA tended to vary when the streptococci were grown in saliva-supplemented CDM, but the number of cells which attached was generally within twofold of that of CDM-grown cells. Attachment of
A. viscosus
S2 and LY7 and of
A. naeslundii
S4 and L13 was generally similar when grown in CDM or in CDM supplemented with saliva, but it tended to increase for organisms grown in CDM supplemented with gastric mucin. None of the strains studied appeared to destroy the blood group reactivity of the added salivary components, and they attached equally well to HA treated with homologous or heterogous saliva from that present in the medium in which they were grown. The
A. viscosus
strains adsorbed in 25 to 40% higher numbers to HA treated with blood type B saliva than with type A saliva, irrespective of the medium used for growth.
S. mutans
H12 cells displayed α- and β-glucosidase and α-galactosidase activity; the
Actinomyces
strains exhibited these activities plus β-galactosidase when grown in all media. However, the levels of these glycoside hydrolases did not correlate with cell adsorption to S-HA. The apparent weak influence of the growth medium on attachment of
S. mutans
was studied further. Strains of
S. mutans
isolated from the saliva of five human donors were made resistant to streptomycin, grown in CDM, and then added to new saliva samples from the respective donors from which they were obtained. The in vitro-grown cells were found to attach to S-HA comparably to
S. mutans
cells present naturally in the saliva.
Evidence for depletion of Ia+ macrophages and associated immunosuppression in African trypanosomiasis
Authors: Bagasra O , Schell R F , Le Frock J L
Published: January 2020

The percentage of Ia antigen-bearing (Ia+) macrophages was significantly lower in mice infected with Trypanosoma rhodesiense than in normal controls. The degree of difference varied with the source of macrophages and time course of infection. The percentage of Ia+ macrophages isolated from spleens 10 days after infection was 71% of that in the controls, and depletion continued until Ia+ macrophages were almost undetectable 30 days after infection. The rate of depletion was slower in the peritoneal cavity. In contrast, Ia+ macrophages were not significantly depleted from the lymph nodes until 30 days after infection. The ability of macrophages from trypanosome-infected mice to present listerial antigen to sensitized T cells was significantly lower than in controls. Immune T cells had significantly less ability (43% of controls) to incorporate thymidine when exposed to splenic macrophages from infected mice during the early stage of disease. This loss of antigen presentation increased during the course of infection. Peritoneal macrophages also exhibited an early loss of ability to present antigen, but no significant decline occurred thereafter. No significant loss of antigen had occurred in the lymph node macrophages 10 days after infection, but during the later stages of the disease a significant loss was detected. Treatment of macrophages from infected and control mice with anti-Iab serum and complement inhibited their ability to present antigen. Our results demonstrate that Ia+ macrophages and their distribution can influence the ability of infected animals to process antigens and may therefore account in part for the immunosuppression observed in trypanosomiasis.
Production of experimental ulcerative colitis in gnotobiotic guinea pigs with simplified microflora
Authors: Onderdonk A B , Franklin M L , Cisneros R L
Published: January 2020

Conventional guinea pigs provided with a solution of 5% (wt/vol) degraded carrageenan as the sole source of oral fluids developed ulcerations of their ceca and large intestines within 30 days. Similar lesions were not detected in germfree guinea pigs treated in an identical manner, suggesting that an intestinal microflora was necessary for development of intestinal lesions. To simplify the bacterial flora required for production of cecal ulcerations, 10 pools consisting of 10 bacterial strains each were isolated from the cecal microflora of carrageenan-treated animals. Groups of germfree guinea pigs were associated with 2 of the 10 pools by orogastric intubation and observed for development of disease. One-half of each group was treated with carrageenan. The two bacterial pools were characterized by the presence of cytopathic effects for WI-38 and Vero cells, increased chemotactic activity, and increased concentrations of long-chain fatty acids. The results indicated that animals associated with those two pools developed cecal ulcerations during carrageenan treatment. Preliminary results also indicated that cecal ulcerations developed in germfree animals mono-associated with a strain of Bacteroides vulgatus isolated from one of the pools, regardless of whether carrageenan was administered, suggesting a bacterial involvement in disease development in the absence of carrageenan treatment.
Effect of Dietary Essential Amino Acid Limitations upon the Susceptibility to
Salmonella typhimurium
and the Effect Upon Humoral and Cellular Immune Responses in Mice
Authors: Petro Thomas M. , Bhattacharjee J. K.
Published: January 2020

We investigated the effects of dietary essential amino acid limitations on the susceptibility of mice to
Salmonella typhimurium
infections and on humoral and cellular immune (cell-mediated immune) responses of mice. Mice fed synthetic diets limited (significantly less than optimum concentration) in a single essential amino acid (leucine, isoleucine, valine, or lysine) for 3 weeks after they were weaned exhibited significantly enhanced susceptibility to
S. typhimurium
infection, as evidenced by the higher levels of mortality and spread of the bacterial cells in their livers and spleens compared with mice fed the control diet. Compared with mice fed the control diet, mice fed the diet limited in leucine had a lower ability to clear
S. typhimurium
cells from the peritoneal cavity 5 min after intraperitoneal injection, whereas mice fed the diet limited in lysine had a greater ability. The in vivo phagocytosis and in vitro bactericidal kinetics against
S. typhimurium
cells by peritoneal macrophages were not significantly different in the control group and the groups of mice fed experimental diets. Certain experimental groups exhibited significantly lower resistance and antibody response against
S. typhimurium
SL3770 on day 5 after immunization with heat-killed
S. typhimurium
SL3770. On day 8 after immunization, the levels of serum antibody against
S. typhimurium
in the mice fed the experimental diets were comparable to the levels in mice fed the control diet. However, the levels of serum transferrin and complement C3 were significantly lower in mice fed certain experimental diets. The cellular immune capacities of mice fed any of the experimental diets were not impaired compared with the capacities of mice fed the control diet, as measured by spleen cell responsiveness to phytohemagglutinin and the ability to clear infecting
Listeria monocytogenes
cells from livers and spleens.
Adherence of Streptococcus sanguis clinical isolates to smooth surfaces and interactions of the isolates with Streptococcus mutans glucosyltransferase
Authors: Hamada S , Torii M , Kotani S , Tsuchitani Y
Published: January 2020

Streptococcus sanguis isolated from human dental plaque were grown in Todd-Hewitt broth. Cells were collected by centrifugation and lyophilized after extensive washing with water. The cell-associated glucosyltransferase (GTase) activities of S. sanguis strains were assayed with [14C]sucrose. Strain differences in GTase activity were significant within the same serotype or biotype or both. The ability of S. sanguis cells to adhere to smooth glass surfaces was generally weak, irrespective of significant cell-associated GTase activity synthesizing water-insoluble, gel-like glucans. Resting cells of most S. sanguis strains bound extracellular GTase from Streptococcus mutans strain B13 (serotype d), resulting in the strong adherence of the S. sanguis cells to smooth glass surfaces in the presence of sucrose. Conversely, S. mutans B13 cells also could bind extracellular GTase from some strains of S. sanguis examined. The sucrose-dependent adherence of S. mutans cells was not altered, although S. sanguis strains from which the extracellular GTases were obtained did not produce significant adherence in the presence of sucrose. In view of these findings, it was suggested that S. mutans GTase could affect the adherence of S. sanguis to smooth tooth surfaces in the oral cavity.
Effects of surgery on neutrophil granulocyte function
Authors: El-Maallem H , Fletcher J
Published: January 2020

The high incidence of postoperative infections raises the possibility of a reduced defense to infection during this period. For this reason, neutrophil function and enzyme activity were investigated after surgical trauma. The microbicidal ability of neutrophils was markedly impaired within 2 h of elective abdominal hysterectomy, but phagocytosis was unaffected. Loss of microbicidal activity was associated with loss of the lysosomal enzyme myeloperoxidase. It is suggested that these changes are due to activation and partial degranulation of circulating neutrophils. Defective microbial killing by individual cells should be compensated by an accompanying rise in the number of circulating neutrophils.
Thymocytotoxic autoantibodies found in mice infected with Schistosoma japonicum
Authors: Kawabata M , Hosaka Y , Kumada M , Matsui N , Kobayakawa T
Published: January 2020

Thymocytotoxic autoantibodies were demonstrated in sera of C3H/HeJms, C57BL/6J, and ddY mice infected with 50 cercariae of Schistosoma japonicum, using C57BL/6J thymocytes as target cells in the trypan blue dye exclusion test. Kinetic study revealed that thymocytotoxic activity began to increase at week 6 of infection, reached a maximum at 8 weeks, and thereafter decreased gradually. Thymocytotoxic antibodies had an optimal reactivity at 4 degrees C and were sensitive to 2-mercaptoethanol treatment, suggesting that they were immunoglobulin M in nature. The cytotoxicity was completely abolished by absorption with C57BL/6J thymocytes but not with S. japonicum parasites or eggs. The antigen reacting with thymocytotoxic antibodies was found in the thymus, brain, spleen, and, to a lesser extent, kidney and liver. In parallel with the appearance of thymocytotoxic antibodies, the increase of background plaque-forming cells to trinitrophenyl, polyvinyl pyrrolidone, and sheep erythrocytes in the spleen of S. japonicum-infected mice suggested that te induction of thymocytotoxic antibodies may be the consequence of polyclonal B-lymphocyte stimulation by the infection.
Influence of prior cellular immunity on the in vitro lymphocyte response to virus antigens after influenza vaccination
Authors: Briggs W A
Published: January 2020

The in vitro peripheral blood lymphocyte response to specific influenza virus antigens was studied before and 2 weeks after trivalent influenza vaccination of 16 healthy persons. Changes in serum hemagglutination inhibition antibody titers were also determined. An inverse correlation was found between the prevaccination antibody titers and the log2 mean-fold increase in antibody titers after vaccination (r = -0.86, P less than 0.01). An inverse correlation was also found between the prevaccination stimulation index and the ratio of postvaccination to prevaccination stimulation index for each virus strain (A/Victoria, r = -0.48, P less than 0.05; A/USSR, r = -0.55, P less than 0.02; and B/Hong Kong, r = -0.55, P less than 0.02). Similar negative correlations were not consistently found with the nonspecific mitogens phytohemagglutinin, pokeweed mitogen, and concanavalin A. These results suggest that the state of cellular as well as humoral immunity to virus antigens before vaccination influence the magnitude of response after vaccination and that antigen-specific suppressor cell activity may be stimulated by vaccination.
Human B lymphocytes produce leukocyte interferon after interaction with foreign cells
Authors: Weigent D A , Langford M P , Smith E M , Blalock J E , Stanton G J
Published: January 2020

Enriched human B-cell populations cocultivated with xenogeneic or allogeneic tumor cells produced 1,000 to 10,000 U of leukocyte interferon per ml. In contrast, cocultivation of enriched plastic-adherent or T-cell populations with xenogeneic or allogeneic cells produced only 10 to 30 U of interferon. The population of cells producing the interferon absorbed to nylon wool and not sheep erythrocytes. They showed a strong mitogenic response to the B-cell mitogen Escherichia coli lipopolysaccharide but not the T-cell mitogen staphylococcal enterotoxin A. In addition, treatment of this cell population with goat anti-human immunoglobulin M and complement depleted the cell population synthesizing the interferon. Together, these in vitro findings strongly suggest that the cells producing most of the interferon after interacting with foreign cells belong to the B-cell population. These results also suggest that the cells that produce most of the leukocyte interferon after interacting in vivo with tumors or other cells made foreign to the body by certain viruses most likely belong to the B-lymphocyte population.
An enterotoxin-negative strain of Yersinia enterocolitica serotype O:3 is capable of producing diarrhea in mice
Authors: Schiemann D A
Published: January 2020

A strain of Yersinia enterocolitica serotype O:3 that consistently produced heat-stable enterotoxin at 22 but not at 37 degrees C and another strain of the same serotype which did not produce enterotoxin at 22 degrees C were both positive for autoagglutination at 35 degrees C, a test that has been related to virulence in yersiniae. Both strains were infective for HeLa cells and produced guinea pig conjunctivitis. Mice infected with either strain through their drinking water developed diarrhea and excreted the organism in high numbers in the feces. A control strain of serotype O:3 positive for enterotoxin and HeLa cell infectivity but negative for autoagglutination was avirulent. Extracts of feces and intestines from mice with diarrhea were negative for enterotoxin. The results indicate that the heat-stable enterotoxin produced in vitro by some strains of Y. enterocolitica and measured by the infant mouse assay plays no role in pathogenesis as described by the mouse diarrhea model.
Histopathological and immunocytochemical studies of Trypanosoma musculi infection of mice
Authors: Hirokawa K , Eishi Y , Albright J W , Albright J F
Published: January 2020

Mice infected with Trypanosoma musculi developed hyperplasia of the spleen, lymph nodes, and liver; in contrast, their thymuses displayed transient involution. All organs returned to normal in a month or less. There was modest anemia, lasting until the parasites were cleared from the bloodstream, followed by a rapid influx of erythrocytes into the blood and a subsequent return to normal erythrocyte numbers. During the first 2 weeks, trypanosomes and trypanosome-derived substances were found in the livers and, in moderate amounts, in the red pulp of the spleens; thereafter, trypanosomes and trypanosome-derived substances gradually decreased in these organs. The lymphoreticular hyperplasia involved a large increase of immunoglobulin G (IgG)-containing cells in the spleens and lymph nodes at 2 weeks of infection. Hyperplasia of immunoglobulin-producing cells correlated with elevation of serum immunoglobulins, especially IgG. Cells producing IgG in the spleens proliferated mainly around the central arterioles of the white pulp, i.e., in the T-cell-dependent areas. The decline of trypanosome-derived substances in the livers and spleens was associated with marked hyperplasia of IgG-containing cells in the spleens and lymph nodes. These results suggest that trypanosome-mediated depression of murine immune responses is attributable to proliferation and terminal differentiation of more-mature lymphoid cells and temporary inhibition of normal maturation of less-mature precursor cells.
Degradation of immunoglobulins A2, A2, and G by suspected principal periodontal pathogens
Authors: Kilian M
Published: January 2020

Attention has recently been focused on immunoglobulin A1 (IgA1) protease production as a possible virulence factor of bacteria implicated in meningitis and gonorrhea. This report demonstrates that suspected principal etiological agents in destructive periodontal disease include bacteria capable of degrading IgA1, IgA2, and IgG. Representative strains of Bacteroides melaninogenicus subsp. melaninogenicus and Capnocytophaga cleaved IgA1 but not IgA2 in the hinge region to yield intact Fab and Fc fragments. All Capnocytophaga strains also cleaved IgG in the same way. The majority of strains of Bacteroides asaccharolyticus and B. melaninogenicus subsp. intermedius caused complete degradation of both IgA1 and polyclonal IgG. However, some strains left the Fc part of IgA1 intact. Several strains were also capable of completely decomposing IgA2 and S-IgA. Significant IgA-cleaving enzyme activity was detected in whole subgingival dental plaque collected from patients with destructive periodontal disease. The results indicate that colonization of the subgingival area by B. asaccharolyticus, B. melaninogenicus, and Capnocytophaga spp. can induce a local paralysis of the immune defence mechanisms, thereby facilitating the penetration and spread of potentially toxic substances, lytic enzymes, and antigens released by the entire subgingival microflora.
Mumps virus replication in human lymphoid cell lines and in peripheral blood lymphocytes: preference for T cells
Authors: Fleischer B , Kreth H W
Published: January 2020

The replication of mumps virus was studied in human continuous lymphoblastoid cell lines (LCLs) with T or B characteristics and in lymphocyte subpopulations derived from peripheral blood. T-LCLs supported effective virus replication as shown by high titers of free and cell-associated virus over 1 to 4 days after infection. By immunofluorescence analysis, the majority of cells were positive for mumps virus antigens. In contrast, the B-cell lines produced low titers of infectious virus, and only a small percentage expressed viral antigens. This resistance of the B-LCLs was found with several mumps virus strains. Cultures of peripheral blood mononuclear cells also supported mumps virus replication. Very high titers of infectious virus (10(8) PFU/ml) were observed in cultures prestimulated with phytohaemagglutinin. Studies with enriched T and B cells point to the activated T lymphocyte as the major virus-producing cell.
Flagellar preparations from Pseudomonas aeruginosa: isolation and characterization
Authors: Montie T C , Craven R C , Holder I A
Published: January 2020

Flagella from various strains of Pseudomonas aeruginosa were isolated by shearing the flagella followed by differential centrifugation to obtain typical filaments as viewed through an electron microscope. Electrophoretic analysis showed a major protein band corresponding to a flagellin with molecular weight of 53,000. Among the strains tested, flagellar antigen (FAg) preparations isolated from strains 1244 and 1210 routinely gave the highest percentage of flagellin, with the least amount of protein impurities, when grown on succinate-mineral salts medium. All FAg preparations contained 3 to 10 micrograms of 2-keto-3-deoxyoctonate-positive material per mg of protein. Strain PA-103 lacked flagella and exhibited no flagellin band, and preparations from PA-103 had a relatively higher content of 2-keto-3-deoxyoctonate. The isolation of highly purified, single-banded flagellin could be accomplished by elution of the 53,000-molecular weight gel band. Amino acid analysis showed 16 amino acids, but no proline. Antisera to FAg preparations were used to demonstrate inhibition of motility of strains RM-46 and M-2. Heated RM-46 FAg antisera and PA-103 antisera did not inhibit motility.
Neutrophil chemotaxis by Propionibacterium acnes lipase and its inhibition
Authors: Lee W L , Shalita A R , Suntharalingam K , Fikrig S M
Published: January 2020

The chemoattraction of Propionibacterium acnes lipase for neutrophils and the effect of lipase inhibitor and two antibiotic agents on the chemotaxis were evaluated. Of the various fractions tested, partially purified lipase (fraction 2c) was the most active cytotaxin produced by P. acnes. Serum mediators were not required for the generation of chemotaxis by lipase in vitro. Diisopropyl phosphofluoridate at low concentration (10(-4) mM) completely inhibited lipase activity as well as polymorphonuclear leukocyte chemotaxis generated by lipase. Tetracycline hydrochloride and erythromycin base at concentrations of 10(-1) mM and 1 mM, respectively, caused 100% inhibition of PMN migration toward lipase or zymosan-activated serum. The inhibiting activity of the antibiotics was directed against cells independently of any effect on lipase. Chemotaxis by P. acnes lipase suggests a wider role for this enzyme in the inflammatory process and the pathogenesis of acne vulgaris.
Differential Complement Resistance Mediates Virulence of
Haemophilus influenzae
Type b
Authors: Sutton Ann , Schneerson Rachel , Kendall-Morris Saundra , Robbins John B.
Published: January 2020

Studies were undertaken to gain insight into the virulence of type b in contrast to the other
Haemophilus influenzae
capsular types. A relationship was found between the comparative virulence of
H. influenzae
types in humans and their resistance to the bactericidal effect of antibody-free complement. Type b was most resistant to the bactericidal effect of complement. The other types could be divided into three groups based upon their susceptibility to complement; this grouping was also related to their structural similarities. No association between virulence and either the biotype, source of isolate, in vitro association with peripheral polymorphonuclear leukocytes, or the total amount of capsular polysaccharide was found. However, among the type b strains, higher levels of cell-associated polysaccharide were associated with increased resistance to complement. The relative virulence of the six
H. influenzae
types in the infant rat model was generally similar to that in humans. After intraperitoneal challenge, type b and type a strains had the lowest 50% effective doses for bacteremia, removed by several logs from the values of the other types. By intranasal challenge, type b strains produced higher rates and levels of bacteremia than did type a strains. High levels of natural bactericidal antibodies to types c and e were found in adult female rats; this finding alone could not account for the differences in virulence among the
H. influenzae
types in the infant rat model. We propose that the virulence of type b strains is due to their greater resistance to the bactericidal activity of serum complement alone. Resistance to type b disease requires serum antibody to induce the complement-mediated reaction.
African trypanosome antigens recognized during the course of infection in N'dama and Zebu cattle
Authors: Shapiro S Z , Murray M
Published: January 2020

The humoral immune responses to Trypanosoma brucei infection were examined in N'dama and in Zebu, two breeds of cattle recognized for their differing susceptibility to trypanosomiasis. Regardless of the clinical course, animals of both breeds produced antibodies to nonsurface trypanosome antigen(s) detectable by both immunodiffusion and immune fluorescence. As a new approach to assessment of the humoral response to trypanosome infection, protein antigens responded to were isolated by immune precipitation, and their molecular weights were determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. This allowed the detection of differences in the immune response which correlated with the clinical course of the disease. All cattle of both breeds which exhibited a capacity to control the disease recognized at least one of three specific antigens: protein of 110,000, 150,000, and 300,000 daltons. The N'dama, which proved less susceptible to the disease, generally responded to more of the three identified trypanosome protein antigens than did the Zebu. Animals which died of trypanosomiasis failed to produce detectable antibodies to any of the three specific proteins, although they sometimes exhibited antibodies to another trypanosome antigen.
Biological activity of a new synthetic muramyl peptide adjuvant devoid of pyrogenicity
Authors: Chedid L A , Parant M A , Audibert F M , Riveau G J , Parant F J , Lederer E , Choay J P , Lefrancier P L
Published: January 2020

Immunostimulant activities of muramyl dipeptide (enhancement of specific immune responses and of nonspecific resistance to infection) were retained by its N-acetylmuramyl-L-alanyl-D-glutaminyl-n-butyl ester derivative, although very large amounts administered intravenously, or even by the very sensitive intracerebroventricular route, did not elicit fever in the rabbit. This analog also appeared to be devoid of other secondary effects which have been observed after administration of muramyl dipeptide.
Reappraisal of lymphocyte responsiveness to concanavalin A during experimental syphilis: evidence that glycosaminoglycans in the sera and tissues interfere ith active binding sites on the lectin and not with the lymphocytes
Authors: Baughn R E , Musher D M
Published: January 2020

No significant differences were noted between the responses of lymphocytes from normal and Treponema pallidum-infected rabbits to concanavalin A. When added to cultures of normal peripheral blood lymphocytes, however, sera and tissue supernatant fluids from infected rabbits were capable of suppressing the response to concanavalin A. Although immune complexes were regularly present in suppressive sera and tissue extracts, additional experiments in which both direct and indirect approaches were used indicated that immune complexes were not responsible for the observed depression. Sequential stimulation studies, done with purified glycosaminoglycan materials obtained from suppressive sera and testicular fluids, and specific absorption studies suggested that this material blocks active sites on the lectin and merely prevents recognition of the mitogen by otherwise functionally active cells.
Immunization of mice by intracutaneous inoculation with viable virulent Cryptococcus neoformans: immunological and histopathological parameters
Authors: Moser S A , Lyon F L , Domer J E , Williams J E
Published: January 2020

Immune responses, including protection and delayed hypersensitivity, were evaluated in experimental murine cryptococcosis. Mice were immunized by the intracutaneous inoculation of viable virulent Cryptococcus neoformans yeasts. Response to the cutaneous infection was evaluated histologically and by cultural assays of the internal organs, as well as by intravenous challenge with the same strain. Protection was assessed by survival, histopathology, and quantitative organ culture. The intracutaneous inoculation of cryptococci resulted in a local inflammatory response that effectively limited dissemination of the organisms systemically and induced the development of delayed hypersensitivity demonstrable with a membrane extract of C. neoformans and with soluble cytoplasmic substances. A protective response was induced by the cutaneous inoculation of cryptococci as well, in that immunized animals survived longer, with about 25% of the challenged group ridding themselves completely of the cryptococci. Protection could be demonstrated by cultural analyses, but all animals, whether control or immunized, allowed considerable multiplication of the inoculum during the first 4 weeks after intravenous challenge. It would appear, therefore, that the protective mechanism(s) required additional antigenic stimulation before it could eventually function to eliminate all cryptococci from tissues. Histologically, there were no differences in pathology of the internal organs between immunized and unimmunized animals. Although the model described herein for the induction of immune responses in murine cryptococcosis has at least one drawback, viz., the presence of cryptococci in the skin lesion of many animals throughout the duration of the experiment, it does have the advantage that the immune responses were stimulated by a virulent strain and only minimal dissemination occurred. Therefore, lymphocytes could be removed from animals that were not contaminated with cryptococci for in vitro and in vivo transfer.
Detection of toxins produced by vibrio fluvialis
Authors: Lockwood D E , Kreger A S , Richardson S H
Published: January 2020

The results of studies with cell-free extracts and culture supernatant fluids of Vibrio fluvialis (a recently recognized, potential enteric pathogen for humans) grown in the absence and presence of lincomycin indicated that the bacterium could produce (i) a factor which causes CHO cell elongation (CEF) similar to that elicited by V. cholerae enterotoxin and by the heat-labile enterotoxin of Escherichia coli, (ii) cytolysin(s) active against erythrocytes, (iii) nonhemolytic, CHO cell-killing factor(s), and (iv) protease(s) active against azocasein. The CEF was heat labile and ammonium sulfate precipitable, and it had an isoelectric point (estimated by sucrose density gradient electrofocusing) and molecular weight (estimated by gel filtration) of about 5.1 and 135,000, respectively.
Antigenic analysis of Legionella pneumophila and Tatlockia micdadei (Legionella micdadei) by two-dimensional (crossed) immunoelectrophoresis
Authors: Joly J R , Kenny G E
Published: January 2020

The antigens of the six serogroups of Legionella pneumophila were compared by two-dimensional (crossed) immunoelectrophoresis by using rabbit antisera to serogroups 1, 2, 3 and 4. The close relationship among the serogroups was shown by the fact that 27 of the 31 antigens demonstrated so far were common. However, distinctive group-specific antigens with slow electrophoretic mobility were observed for serogroups 1, 2, 3, and 4. When intact serogroup 1 organisms were extracted with EDTA, the group-specific antigen was recovered in a virtually pure form. The group-specific antigen was pronase resistant, heat stable, and amphiphilic and had a surface location, all of which are properties suggestive of lipopolysaccharide. L. pneumophila shared four to five antigens with Tatlockia micdadei (Legionella micdadei). The large number of common antigens in the serogroups of L. pneumophila has important implications for the specific detection of antigens and antibodies by fluorescent and other tagged antibody methods.
Cytotoxic cells induced after Chlamydia psittaci infection in mice
Authors: Lammert J K
Published: January 2020

The ability of spleen cells from Chlamydia psittaci-infected mice to lyse C. psittaci-infected and uninfected target cell monolayers was studied. The cytotoxicity assay used was a terminal label method in which the number of adherent target cells surviving the interaction with effector cells was determined by measuring the uptake of [3H]uridine by such cells. It was observed that in the first few days postinfection (3 to 5), spleens contained cells that lysed infected and uninfected targets with equal efficiency. Subsequently, infected targets were killed primarily. The activity of effector spleen cells for infected targets continued, although at a reduced level, beyond 21 days postinfection. Intact effector cells were required since a disruption by sonication resulted in a loss of cytotoxicity. The enhanced killing observed with infected targets was also observed when target cells were sensitized with heat- or UV-inactivated C. psittaci. This study suggests that the induction of cytotoxic cells after C. psittaci infection may contribute to the ability of the host to control multiplication of the microorganism.
Effect of infectious bovine rhinotracheitis virus infection on bovine alveolar macrophage function
Authors: Forman A J , Babiuk L A
Published: January 2020

Bovine alveolar macrophages isolated in culture were assessed for immunological activity in assays for Fc and complement receptors, for phagocytosis, and for effector cell function in antibody-dependent cell cytotoxicity. In the case of uninfected alveolar macrophages, Fc receptors were detected on approximately 94% of macrophages and complement receptors were detected on 39%. Phagocytosis of immunoglobulin G-coated sheep erythrocytes occurred in 58% of macrophages, and phagocytosis of opsonized Candida parapsilosis, mediated by the complement receptor, was observed in 68% of cells. Alveolar macrophages were efficient effector cells in antibody-dependent cell cytotoxicity. Infection of macrophages with infectious bovine rhinotracheitis (IBR) virus resulted in reductions in Fc-mediated receptor activity and phagocytosis after approximately 12 and 6 h, respectively. Complement receptor activity was initially elevated and then markedly reduced. Macrophages retrieved from IBR-immune and -susceptible donors were affected to a similar extent. The ability of macrophages to participate in antibody-dependent cell cytotoxicity was reduced dramatically from 2 h after IBR virus infection, suggesting that IBR virus-infected alveolar macrophages undergo alterations in immunological activity long before morphological changes in the cells become apparent.
Adhesion of type A Pasteurella mulocida to rabbit pharyngeal cells and its possible role in rabbit respiratory tract infections
Authors: Glorioso J C , Jones G W , Rush H G , Pentler L J , Darif C A , Coward J E
Published: January 2020

Pasteurella multocida serotype A was found in association with the mucosal epithelium of the nasopharynges of rabbits with respiratory tract infections. The bacteria specifically attached to squamous epithelial cells of the pharyngeal mucosa both in vivo and in vitro and to some tissue culture cell lines such as HeLa. All strains with serotype A capsules were adhesive. With the exception of one serotype D strain, strains with capsular serotypes B, D, and E were at least 10-fold less adhesive. Bacterial adhesiveness was much reduced after pronase digestion, heat treatment, and homogenization, but removal of the hyaluronic acid capsule increased adhesion. Electron microscopy revealed that fimbriae were produced by an adhesive pasteurella strain, but not by two nonadherent strains. The attachment of the former strain to pharyngeal and HeLa cells was inhibited by N-acetyl-D-glucosamine. Together, these findings suggest that this amino sugar may be a component of the receptor on both animal cell surfaces and that the fimbriae may be the adhesions. It is proposed that bacterial attachment has a role in colonization and infection of rabbit upper respiratory mucosae.
Participation of complement in host defense against encapsulated Haemophilus influenzae types a, c, and d
Authors: Corrall C J , Winkelstein J A , Moxon E R
Published: January 2020

Each of the serotypes of Haemophilus influenzae (types a to f) may colonize the respiratory tract of humans, but only type b strains commonly cause invasive systemic infections. To investigate the role of complement in immunity to encapsulated non-type b strains, rats were depleted of C3 with cobra venom factor and challenged with representative serotypes of H. influenzae (type a, b, c, or d) by different routes. After intravenous challenge, rats depleted of C3 had a greater incidence and magnitude of bacteremia with each of the serotypes when compared with normal controls. Intraperitoneal inoculation of type b organisms resulted in meningitis in normal and C3-depleted rats, but only C3-depleted, and not normal, rats developed meningitis after inoculation of serotype a, c, or d. In contrast to systemic inoculation, intranasal challenge with the different serotypes resulted in bloodstream invasion and meningitis only after challenge with type b organisms. These data suggest that complement plays a significant role in immunity to encapsulated, non-type b H. influenzae through its effect on bloodstream clearance.