bluuebunny/crossref_metadata_2025 huggingface dataset:
Lymphocyte response to T-cell mitogen during experimental gingivitis in humans
Authors: Lang N P , Smith F N
Published: January 2020

This study was conducted to evaluate the dose response relationships of peripheral blood lymphocytes (PBL) by stimulation of phytohemagglutinin (PHA) during the onset of oral inflammation. Eleven dental students underwent a 3-week experimental gingivitis program (Löe et al., 1965). At time zero, weeks 1, 2, and 3, and after 1 week of reinstituted oral hygiene (week 4), the plaque accumulations were evaluated, the degree of gingival inflammation was assessed, and a blood sample was taken. Quadruplicate microcultures each containing 2 x 10(5) PBL in 0.2 ml of tissue culture medium 199 and 10% fetal calf serum were stimulated with five concentrations of PHA (10 to 0.5 mug/ml) and incubated for 78 h at 37 C in 5% CO2. [3H]thymidine was added to each culture for the final 8 h. The cultures were then harvested and counted by liquid scintillation, and stimulation indexes (SI) were determined. At time zero the maximum PBL response occurred at a PHA concentration of 5 mug/ml (SI = 100). During weeks 1, 2, and 3 the location of the maximum PBL response shifted to a lower PHA concentration (1.0 mug/ml) and increased to over SI =400. The phenomenon of shifting peak PHA responses to lower PHA concentrations could be observed after only 1 week of developing gingival inflammation. The PBL response returned to pre-experimental values after 1 week of reinstituted oral hygiene, which resolved the oral inflammation. The findings show that a dose response relationship exists between PHA concentrations and the PBL response. If these dose response changes seen during developing gingival inflammation are ignored, either a decrease, increase, or no change in PBL response can be shown depending upon the PHA concentration evaluated. Owing to the dose-dependent nature of this PBL response, it is advisable to routinely use dose response curves in order to properly evaluate the full responsiveness of PBL to mitogenic substances.
Immunochemical analysis of distinct cellular antigens isolated from a nontypable bovine strain of group B streptococci
Authors: Toole B , Kane J A , Karakawa W W
Published: January 2020

Four immunologically distinct antigens were isolated from a bovine strain of group B streptococci, designated 14 Mi. Chemical analysis indicated that two of the cell surface antigens consisted of glucose, galactose, and glucosamine, whereas the other cell surface antigen, an acidic protein, contained a predominance of aspartic acid, glutamic acid, and alanine. A cell wall-associated triheteroglycan consisting of galactose, glucose, and glucosamine was isolated from strain 14 Mi by 10% trichloroacetic acid. Immunochemical studies suggested that this glycan is type specific and consists of an immunodominant alpha-linked galactosyl-glucose disaccharide.
Epstein-Barr virus interactions with human lymphocyte subpopulations: virus adsorption, kinetics of expression of Epstein-Barr virus-associated nuclear antigen, and lymphocyte transformation
Authors: Menezes J , Jondal M , Leibold W , Dorval G
Published: January 2020

In order to further understand Epstein-Barr virus (EBV)-lymphocyte interactions, we investigated a chain of events including: (i) EBV binding to human lymphocyte subpopulations; (ii) the earliest appearance of EBV-determined nuclear antigen (EBNA) in the lymphocytes after EBV infection; and (iii) establishment of continuous lymphoblastoid cell lines (LCL) by infecting with EBV different types of lymphocyte preparations from the same as well as from different donors. By using direct membrane immunofluorescence assay, we found that only a small fraction of human peripheral blood and cord blood lymphocytes (CBL), and possibly less than 31% of the T cell-depleted lymphocyte population, carry receptors for P3HR-1 strain of EBV. The number of cells carrying receptors for EBV did not vary considerably among different blood lymphocyte populations from several normal donors. EBV adsorption on lymphocyte subpopulations showed that purified thymus-dependent (T) cells and thymocytes did not adsorb EBV, in contrast to T cell-depleted lymphocyte populations and lymphoid cells from fetal liver and spleen. In CBL infected with EBV strain B95-8, EBNA was detected by anti-complement immunofluorescence as early as 18 h after infection. This indicates that EBNA is the earliest detectable EBV-determined intracellular antigen to appear after infection and before or during lymphocyte transformation by EBV. Transformation was observed only in lymphocyte cultures containing detectable thymus-independent B cells but not in cultures of purified T cells. With one exception (es-b-1), all the EBV-transformed LCL from different origins carried surface-bound immunoglobulins (a B cell marker). These included also the 10 LCL obtained by infecting cultures of adherent cells from different donors. With regard to its surface markers, ES-B-1 appeared to be an exceptional EBV genome-carrying line, and it also lacked the ability to form spontaneous rosettes with sheep erythrocytes (a T cell marker). Therefore, it is possible that ES-B-1 was derived from an atypical B cell or B cell precursor or from a so-called "null cell" transformed by EBV.
Naturally occurring antiglobulin factors in virus neutralization: homoreactant as a factor enhancing neutralization of the infectious complex of poliovirus with the Fab' antibody fragment
Authors: Kulberg A J , Pervikov J V
Published: January 2020

A factor present in normal rabbit sera enhanced the neutralization of the infectious complex of poliovirus with the pepsin Fab' fragment of rabbit immunoglobulin G (IgG) antibody but showed no activity for the infectious complex of the same virus with IgG antibody. The factor was associated with IgG, and its activity was inhibited by the pepsin Fab' fragment of normal rabbit IgG. The data suggest that the enhancing factor belongs to naturally occurring antiglobulin to the homologous Fab' fragment (pepsin homoreactant).
Factors influencing the production of interferon from L cells
Authors: Weber J M , Greenlees J L , Stewart R B
Published: January 2020

The production of interferon from Newcastle disease virus-infected mouse L929 cells was investigated in relation to superinduction procedures, cell density, cellular cyclic adenosine 3',5'-monophosphate (cAMP) levels, and rate of incorporation of 14C-labeled protein hydrolysate into trichloroacetic acid-precipitable material. Densely populated cultures did not have their interferon production enhanced through "superinduction" using cycloheximide, actinomycin D, or the two antimetabolites in combination. These dense cultures produced more interferon per cell than less dense cultures, even though the interferon production from the latter cells could be enhanced two- to threefold by cycloheximide or combined cycloheximide and actinomycin D. Cells in densely populated cultures relative to those from sparsely populated cultures were smaller in volume, had a correspondingly reduced protein content and a lower concentration of cAMP, and were less able to concentrate 14C-labeled protein hydrolysate, although proportionally they were just as efficient in incorporating labeled precursors into trichloroacetic acid-precipitable polypeptides.
Comparison of mouse strain skin sensitivities to anaphylactic mediators and susceptibility to passive cutaneous anaphylactic reactions
Authors: Justus D E , Saelinger C
Published: January 2020

CFW, ICR, and C57Bl/6J mouse strains were examined and compared for their levels of skin sensitivity to histamine and mellitin (a potent mast cell degranulator) and for their susceptibilities to immunoglobulin E-induced passive cutaneous anaphylactic (PCA) reactions. ICR mice were found to exhibit the highest level of sensitivity to histamine and mellitin, whereas C57Bl/6J exhibited the least. CFW mice proved to be the best PCA recipients, whereas ICR mice were the poorest. On the basis of this evidence, no direct correlation is indicated between level of sensitivity to anaphylactic mediators and degree of susceptibility to immunoglobulin E-induced PCA reactions.
Suppression of cell-mediated immunity after infection with attenuated rubella virus
Authors: Ganguly R , Cusumano C L , Waldman R H
Published: January 2020

The effects of attenuated rubella virus infection upon cell-mediated immunity of human volunteers were studied. The volunteers received the vaccine either by nose drops or by the subcutaneous route. Changes in cell-mediated immunity in terms of delayed cutaneous sensitivity to recall antigens, phytohemagglutination stimulation, and spontaneous migration inhibitory factor-like activity were studied at various time periods after infection. Spontaneous migration inhibitory factor-like activity was studied on supernatants of the lymphocytes obtained from the volunteers and incubated for 72 h in the absence of any antigens. A significant proportion of the volunteers showed suppression of one or more parameters of cell-medicated immunity tested by week 2 of infection compared to the control; however, there was no correlation between suppression of the various parameters studied. No difference was noticed in the incidence of cell-mediated immunity suppression between nose drops and subcutaneous route groups.
Staphylococcal scalded-skin syndrome: development of a primary binding assay for human antibody to the exfoliative toxin
Authors: Wiley B B , Glasgow L A , Rogolsky M
Published: January 2020

Exfoliative toxin (ET) from a phage group II Staphylococcus aureus strain causing staphylococcal scalded-skin syndrome was purified by electrofocusing. Ampholytes and salts were removed from the final product by column chromatography on G-50 Sephadex. Sodium dodecyl sulfate-polyacrylamide gels of the final product yielded a single band upon gel electrophoresis, even when 60 mug of protein was placed in the gels. Radiolabeling of the purified toxin with 125I yielded a product that still caused exfoliation of suckling mice, indicating that the toxin was still biologically active. A radioimmunobinding assay was developed and used to test rabbit and human sera for antibodies to exfoliative toxin. Although the maximum percentage of binding was not as high as expected (approximately 40%), it was postulated that either iodination had not been sufficiently vigorous or the toxin had sustained immunological damage. The assay was reproducible and more sensitive than the existing neutralization method and readily applicable to the testing of human sera for exfoliative toxin antibodies.
Changes in lactoferrin, immunoglobulin G, bovine serum albumin, and alpha-lactalbumin during acute experimental and natural coliform mastitis in cows
Authors: Harmon R J , Schanbacher F L , Ferguson L C , Smith K L
Published: January 2020

An experimentally induced Escherichia coli infection of a bovine mammary gland resulted in a 30-fold increase in lactoferrin (Lf) concentration in the mammary secretion by 90 h postinoculation and a 4-fold increase in total daily production of Lf by 264 h postinoculation in the infected quarter. A simultaneous rise and fall of bovine serum albumin (BSA) and immunoglobulin G (IgG) concentrations occurred during the acute phase of the infection. Peak BSA and IgG levels were reached 36 h before peak Lf levels. BSA concentrations declined rapidly after the acute phase, whereas IgG and Lf levels remained elevated and decreased slowly as the infection subsided. A decline in alpha-lactalbumin concentration by 48 h postinoculation indicated decreased synthetic capability. The increased Lf production may be a result of a specific response of secretory tissue to inflammatory agents and thus the infectious process. Analogous changes in Lf, IgG, and BSA were observed during a natural coliform infection. Sephadex G-200 chromatography of mastitis skim milk showed that Lf approximated the monomer (molecular weight 77,100) early in infections progressed and abated, the apparent molecular weight of Lf increased to approximately that of the trimer and subsequently decreased to about 1.5 times that of the monomer.
Human fallopian tubes in organ culture: preparation, maintenance, and quantitation of damage by pathogenic microorganisms
Authors: McGee Z A , Johnson A P , Taylor-Robinson D
Published: January 2020

An experimental organ culture model has been developed in which rates of damage to fallopian tube mucosa by agents of sexually transmitted diseases can be quantitated. This required assessment of the effect on organ cultures of such variables as the anatomic area of the fallopian tube employed, endocrinological status of the donor, and composition of media. Organ cultures established from the ampulla of tubes of nonpregnant, premenopausal women and maintained with Eagle minimal essential medium containing 0.05 M N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid buffer were most suitable for quantitative studies. Various means of quantitating damage to fallopian tube mucosa were evaluated. Of these, sequential estimations of ciliary vigor and percentage of the periphery of fallopian tube pieces with active cilia proved the most successful. To assess the specificity of the model, fallopian tube organ cultures were infected with Neisseria gonorrhoeae or N. pharyngis, a commensal Neisseria. Damage by N. gonorrhoeae was significantly greater than that by N. pharyngis at each period of observation (P less than 0.001), suggesting that, by using the model, differences in virulence can be determined in vitro that reflect differences in virulence for humans. This model is a potentially valuable tool for studying the interaction of human genital mucosa with known or suspected agents of sexually transmitted diseases.
Antiviral activity of Brucella abortus preparations; separation of active components
Authors: Feingold D S , Keleti G , Youngner J S
Published: January 2020

Injection into mice of heat-killed Brucella abortus or aqueous ether-extracted B. abortus (Bru-pel) induced a "virus-type" interferon response, with peak titers at 6.5 h. The animals also were protected against challenge with otherwise lethal doses of Semliki forest virus. Extraction of either heated B. abortus or BRU-PEL with a mixture of chloroform-methanol (2:1, vol/vol) (C-M( yielded an insoluble residue (extracted cells) and a C-M extract. Neither extracted cells nor C-M extract alone induced interferon or afforded protection against Semliki forest virus infection in mice. Full interferon-inducing and protective activity was restored when extracted cells were recombined with C-M extract. C-M extract from heat-killed Escherichia coli also was effective in restoring activity to extracted Brucella cells. Neither heat-killed E. coli nor its C-M extract was active, nor was C-M estracted E. coli recombined with the C-M extract from B. abortus. These results suggest that the interferon-inducing and antiviral protective properties of B. abortus are constituted of a C-M-extractable component that is common to B. abortus and E. coli and an unextractable component that is unique to B. abortus.
Adjuvant effect of cord factor, a mycobacterial lipid
Authors: Saito R , Tanaka A , Sugiyama K , Azuma I , Yamamura Y
Published: January 2020

Cord factor was a good adjuvant in mice and rats but exerted little if any adjuvant effect in guinea pigs. In rats, cord factor not only enhanced antibody production but also induced delayed hypersensitivity. Wax D was a weak adjuvant in mice. Cord factor caused a marked inflammatory swelling at the sites of injection in mice, but it caused no such swelling in rats and guinea pigs.
In vivo and in virto cellular responses to cytoplasmic and cell wall antigens of Histoplasma capsulatum in artificially immunized or infected guinea pigs
Authors: Domer J E
Published: January 2020

Guinea pigs were infected with different doses of yeasts of Histoplasma capsulatum or artifically immunized with several concentrations of unextracted yeast cell walls, and then tested in vivo and in vitro for cell-mediated responses to various subcellular fractions of the fungus. Three types of cell-mediated responses were measured, viz., skin test activity, production of migration inhibition factor, and lymphocyte transformation. Positive cutaneous reactions were elicited in animals immunized with 100 or 1,000 mug of cell walls when such animals were skin-tested with cell wall glycoprotein of soluble cytoplasmic substances, whereas animals immunized with 2,000 mug of cell walls did not react significantly greater than unsensitized animals when skin-tested with the same antigens. Histoplasmin did not elicit cutaneous sensitivity in guinea pigs infected with the smallest inoculum, 6 X 10(5) yeast cells, or in animals immunized with cell walls, regardless of the concentration of cell walls used as immunogen. However, hypersensitivity to H. capsulatum could be detected with cytoplasmic substances in animals infected with 6X 10(5). In guinea pigs infected with larger doses, i.e., 10 X 10(7), 15 X10(7), or 20 X 10(7), hypersensitivity could be detected with histoplasmin, cell wall glycoprotein, a ribosome-rich fraction, and soluble cytoplasmic substances. Both cell wall glycoprotein and soluble cytoplasmic substances were functional in migration inhibition factor assays with peritoneal exudate cells from animals immunized with 100 or 1,000 mug of cell walls. The transformation of lymphocytes from infected and artificially immunized guinea pigs in the presence of cell wall glycoprotein and soluble cytoplasmic substances was variable and unpredictable, the lymphocytes from some animls within a given group transforming and those from other animals showing no evidence of stimulation. Moreover, the level of stimulation could not be correlated with the degree of dermal hypersensitivity. These findings suggest that cell wall glycoprotein, and the fractions containing ribosomes and soluble cytoplasmic substances, could be useful antigens in assays for cellular immunity, and warrant further investigation with respect to specificity and active components.
Cell-mediated immune response to Salmonella typhimurium infection in mice: development of nonspecific bactericidal activity against Listeria monocytogenes
Authors: Zinkernagel R M
Published: January 2020

Generation of the cell-mediated immune response of CBA/H mice against Salmonella typhimurium (C5S) was monitored by measuring the nonspecifically increased bactericidal activity of macrophages against Listeria monocytogenes. The appearance of detectable levels of macrophage activation was inversely related to the initiating infectious dose. With 3 X 10(3) infecting C5S organisms, significant activity was demonstrable after day 3. Immunity controlled a challenge with a streptomycin-resistant strain of S. typhimurium (C5R) successfully only by approximately day 7. In the period of increasing activity against L. monocytogenes, growth of C5R was only delayed. Since such an effect could not be demonstrated in Listeria-infected mice, these findings suggest that immunity against C5R necessitates specific factors besides macrophage activation.
Demonstration of macrophage chemotactic factors in the aqueous humor during experimental immunogenic uveitis in rabbits
Authors: Sher N A , Foon K A , Fishman M L , Brown T M
Published: January 2020

Factors in the queous humor capable of increasing the random migration and chemotaxis of monocytes were demonstrated during experimental uveitis in the rabbit. Injection of endotoxin-free human serum albumin into the vitreous produced a severe inflammation detectable after 7 days and maximal between 12 to 21 days. Aqueous humor was measured for chemotactic activity with a modified Boyden chamber, which permitted the use of volumes of less than 0.025 ml. Chematactic activity was measurable during the primary inflammation and remained elevated for a short period of time after clinical inflammation and anterior chamber cellular reaction had decreased. A severe reinduction uveitis could be initiated by the intravenous injection of human serum albumin after day 30. Chemotactic factors could be measured at high titers by 8 h after this intravenous challenge.
Interaction of Nocardia asteroides with cultured rabbit alveolar macrophages
Authors: Beaman B L , Smathers M
Published: January 2020

The interaction between virulent and less virulent strains of Nocardia asteroides and cultured rabbit alveolar macrophages was studied. It was shown that cells of the less virulent strain (N. asteroides 10905) were rapidly phagocytized and destroyed. However, some cells were able to avoid being killed, and they persisted within the macrophage in an altered, gram-negative form. These variants apparently increased in numbers after several days within the macrophage population, so that at 9 days postinfection more colony-forming units per macrophage were recovered than at 3 h. Little or no extracellular growth was observed in the tissue culture medium. During the increase at 9 days, both transitional-phase variants and L-forms of N. asteroides were isolated from the macrophages but not from the medium. Gram-positive bacterial cells were never observed in 9-day infected macrophages. In contrast, cells of the more virulent strain (N. asteroides 14759) were not destroyed after being ingested. After 6 h postinfection, it was observed that the number of colony-forming units per macrophage had increased significantly. There was no corresponding increase in extracellular organisms observed in the culture medium. Therefore, cells of N. asteroides 14759 were able to grow rapidly within cultured rabbit alveolar macrophages. Upon continued incubation of the infected cells (24 h postinfection), it was shown that this strain of Nocardia grew out of the macrophages as acid-fast branching filaments. From these data, it is clear that the initial interaction between N. asteroides and unstimulated, nonimmune alveolar macrophages depends upon the relative virulence of the nocardial strain.
Indirect blastogenesis of peripheral blood leukocytes in experimental gingivitis
Authors: Gaumer H R , Holm-Pedersen P , Folke L E
Published: January 2020

The blastogenic response of peripheral blood leukocytes to lipopolysaccharide (LPS) was followed over a short course of experimental gingivitis, developed in human volunteers who strictly avoided oral hygeine procedures for periods up to 9 days. Eleven young males initially received thorough dental prophylaxes and supervised oral hygeine until they acquired optimal gingival health. At this point, leukocytes (5 X 10(5)) incubated with 1.5 to 25 mug of LPS in serum-free media showed no response as measured by tritiated thymidine uptake. Coincubation of cells with LPS and phytohemagglutinin (PHA), however, caused synergistic enhancement of blastogenesis in every LPS-PHA dose combination tried. With progressive accumulation of dental plaque and the concomitant development of gingival inflammation, this synergistic response was lost and replaced, proportionately, by a direct response to LPS. The leukocyte response to PHA was marginally enhanced with gingivitis.
Further studies of the physical and metabolic properties of foot-and-mouth disease virus temperature-sensitive mutants
Authors: Richmond J Y , Polatnick J
Published: January 2020

Three temperature-sensitive (ts) mutants of foot-and-mouth disease virus were classified as ribonucleic acid negative and as belonging to the same complementation group when measured by virus yields and [3H] uridine incorporation in paired, mixed infections at the nonpermissive temperature (38.5C). Mutant ts-22, the only mutant able to produce plaques at 38.5 C, was more sensitive to acid than were the parental wild-type or other mutant viruses. Diethylaminoethyl-dextran did not enhance the plaque-forming ability of the mutant viruses at 38.5C. All of the viruses inhibited host cell protein syntehsis at both permissive (33C) and nonpermissive (38.5C) temperatures.
Salmonellosis in mice: immunization experiments with salmonella-escherichia coli hybrids
Authors: Kiefer W , Gransow P , Schmidt G , Westphal O
Published: January 2020

Mice vaccinated with Escherichia coli hybrids experesing Salmonella O antigens were protected against lethal challenge doses of Salmonella strains. Counts of challenge bacteria in mouse organs revealed that a live hybrid vaccine was slightly more efficient than an acetone-killed vaccine.
Differential inhibition of Streptococcus mutans in vitro adherence by anti-glucosyltransferase antibodies
Authors: Kuramitsu H K , Ingersoll L
Published: January 2020

Antibodies prepared against an insoluble-soluble glucan-synthesizing fraction significantly inhibited in vitro adherence of Streptococcus mutans, whereas antibodies directed against a soluble glucan-synthesizing fraction were much less inhibitory.
Interaction of Mycoplasma dispar and Mycoplasma agalactiae subsp. bovis with bovine alveolar macrophages and bovine lacteal polymorphonuclear leukocytes
Authors: Howard C J , Taylor G , Collins J , Gourlay R N
Published: January 2020

Mycoplasma dispar and Mycoplasma agalactiae subsp. bovis survived or grew in cultures of bovine lacteal polymorphonuclear leukocytes or bovine alveolar macrophages. In the presence of specific bovine antibody, macrophages and polymorphonuclear leukocytes appeared to kill both species of mycoplasma. Specific rabbit antisera also promoted the killing of these mycoplasmas by bovine macrophages but had no demonstrable activity for bovine polymorphonuclear leukocytes. It is suggested that phagocytosis of these mycoplasmas by bovine cells occurs only in the presence of specific antibody. The experiments also indicate that differences exist between bovine polymorphonuclear leukocytes and macrophages with regard to their receptor sites for immunoglobulins.
Factors influencing the immune enhancement of intrapulmonary bactericidal mechanisms
Authors: Jakab G J
Published: January 2020

The effect of specific immunization on the antibacterial defense mechanisms of the murine lung was assessed against Streptococcus pneumoniae, Staphylococcus aureus, Staphylococcus aureus (Smith), Serratia marcescens, Klebsiella pneumoniae, Proteus mirabilis, and Pseudomonas aeruginosa. Immunization by aerosol inhalation significantly enhanced the intrapulmonary killing of Pseudomonas aeruginosa and Proteus mirabilis but not the remaining organisms. With P. mirabilis, systemic immunization induced higher titers of specific serum agglutinins as compared with local respiratory tract immunization; however, local immunization was more effective in enhancing pulmonary bactericidal activity than was parenteral vaccination. Passive immunity against P. mirabilis or aerogenic challenge with preopsonized P. mirabilis significantly enhanced intrapulmonary killing of the homologous organism. With S. aureus, pulmonary bactericidal activity was not accelerated by aerosol challenge with the preopsonized organism, nor was it accelerated in passively immunized mice. These data demonstrate that the immune enhancement of pulmonary bactericidal activity is governed by the bacterium used for challenge and the route of immunization. The results further demonstrate that with P. mirabilis, antibody-mediated mechanisms are involved in the immune enhancement of pulmonary bactericidal activity.
Plasmid-mediated properties of a heat-stable enterotoxin-producing Escherichia coli associated with infantile diarrhea
Authors: Wachsmuth I K , Falkow S , Ryder R W
Published: January 2020

The plasmid mediation and transmissibility of heat-stable enterotoxin production and multiple antibiotic resistance have been demonstrated for Escherichia coli O78:K80:H12 epidemiologically incriminated in a hospital outbreak of infantile diarrhea. The conjugal transfer of a 67 X 10(6) - and a 30 X 10(6)-dalton plasmid was associated with the transfer of resistances and enterotoxin production, respectively. Using antibiotics to select E. coli K-12 transconjugants from a one-step bacterial cross, all of the monitored resistances were transferred concurrently, and 36% of the resistant transconjugants produced enterotoxin.
Enzymatic activities leading to pyrimidine nucleotide biosynthesis from cell-free extracts of Rickettsia typhi
Authors: Williams J C , Peterson J C
Published: January 2020

Cell-free extracts from Rickettsia typhi were examined for the presence or absence of pyrimidine phosphotransferase enzymes and compared with the enzymes of mouse L cells and Salmonella typhimurium. The organisms were grown in mouse L cells and in the yolk sacs of chicken embryos, purified by Renografin density gradient centrifugation, and ruptured in a French pressure cell. The enzymes for the reutilization of uridine and thymidine, uridine kinase (EC 2.7.1.48) and thymidine kinase (EC 2.7.1.21), were not detected in R. typhi extracts with the phosphate donors effective for control enzymes. The following enzyme activities were demonstrated in R. typhi: uridine-5'-monophosphate kinase (UMPK, EC 2.7.4.4), deoxythymidine-5'-monophosphate kinase (dTMPK, EC 2.7.4.9), and nucleosidediphosphate kinase (NDPK, EC 2.7.4.6). Physicochemical and enzymatic analyses demonstrated that the pyrimidine nucleotide kinases of R. typhi were not of host origin and that the source (yolk sac and mouse L cells) did not influence the relative enzymatic activities. The specific activities of UMPK and dTMPK were higher when the rickettsiae were harvested before embryo death, whereas NDPK levels were slightly decreased. The specific activities of UMPK, dTMPK, and NDPK were comparable to those of S. typhimurium, and consequently the rickettsiae have potential for the anabolism of monophosphates, as do the host-independent bacteria. These results suggest that R. typhi cannot utilize host uridine or thymidine pools directly but must rely on themonophosphorylated molecules of the host cell or must synthesize the monophosphates de novo.
Hepatitis B antigen-associated deoxyribonucleic acid polymerase activity and e antigen/anti-e system
Authors: Imai M , Tachibana F C , Moritsugu Y , Miyakawa Y , Mayumi M
Published: January 2020

Serum samples of 403 asymptomatic blood donors carrying hepatitis B surface antigen (HB5Ag) were concentrated threefold and tested for e antigen and antibody to e antigen (anti-e) by immunodiffusion. Hepatitis B antigen (HBAg)-associated deoxyribonucleic acid (DNA) polymerase activity was specifically determined by the difference in incorporation of [methyl-3H]thymidine 5' -triphosphate into DNA by an aliquot of centrifuged serum samples after it had been treated either with normal rabbit serum or with rabbit antibody to HBSAg. All of 58 serum samples containing e antigen revealed HBAg-associated DNA polymerase activity, whereas none of 96 samples containing anti-e did. In the remaining 249 samples in which neither e antigen nor anti-e was found, 62 showed specific DNA polymerase activity, although at lower levels than the samples containing e antigen.
Radioimmunofluorescent antibody technique for detection of reovirus antigen in cell culture
Authors: McCammon J R
Published: January 2020

Antibody against reovirus type I must partially purified and conjugated with fluorescein isothiocyanate (FITC). The FITC-labeled antibody was then conjugated with 125I. A gamma globulin fraction of normal sera was similarly labeled with FITC followed by a 131I label. The FITC + 125I-labeled immune reagent was then mixed on an equal protein basis with the FITC + 131I control reagent. This mixture was used to stain acetone-fixed reovirus-infected cover slips. After staining, the cover slips were examined by fluorescence microscopy. Infected cover slips demonstrated characteristic reovirus immunofluorescence, whereas uninfected cover slips were negative. After visual examination, the cover slips were placed in tubes and counted in a two-channel gamma analyzer. By comparing the quantitative isotope data with the qualtitative information from immunofluorescence on a single preparation, it was possible to correlate antigen production sites with quantitative production values.
Immunological control mechanism against cholera toxin: interference with toxin binding to intestinal receptors
Authors: Wu A L , Walker W A
Published: January 2020

The immunological control mechanism against cholera toxin (CT) in the small intestine of rats was studied in vivo. CT binding to intestinal receptors was determined by injected radiolabeled CT into the loops of rat small intestine and subsequently separating purified microvillus membranes from mucosal scrapings of those loops. substantial radioactivity (10(5) cpm/mg of microvillus protein) was present in microvillus fractions of small intestine exposed to 125I-labeled CT compared to radioactivity (10(2) cpm/mg) in fractions from intestine exposed to radiolabeled bovine serum albumin (BSA) used as a control. CT binding to intestinal receptors was significantly inhibited (P less than 0.02) in rats immunized with crude toxin by a combined intraperitoneal and oral method compared to CT binding in animals immunized with BSA or controls, suggesting a specific relationship between intestinal antitoxin and inhibition of binding. Furthermore, ligated ileal loops from CT-immunized animals showed a significant decrease in fluid accumulation when exposed to CT compared to loops from control or BSA-immunized animals, suggesting that antitoxins also interfered with the biological action of CT under conditions of immunization. These studies provide direct evidence that intestinal antitoxins protect against CT-induced diarrhea by interfering with the attachment of the toxin to the intestinal microvillus surface.
Serum bactericidal activity in the horseshoe crab, Limulus polyphemus
Authors: Pistole T G , Furman R M
Published: January 2020

Serum from the horseshoe crab, Limulus polyphemus, was examined for bactericidal activity against five species of bacteria. Greatest activity was found against Pseudomonas putida and Flavobacterium sp.; with the former, serum dilutions as high as 1:20 were capable of reducing viable counts by 50% within 2 h. Bactericidal activity of a significantly lesser magnitude was demonstrated against Serratia marcesencs and Salmonella minnesota. No killing was seen when the lobster pathogen Aerococcus viridans (formerly Gaffkya homari) was used. The cidal activity against Flavobacterium sp. remained relatively consistent for 6 months.
Synergistic effect on mortality in mice with murine cytomegalovirus and Pseudomonas aeruginosa, Staphylococcus aureus, or Candida albicans infections
Authors: Hamilton J R , Overall J C , Glasgow L A
Published: January 2020

A synergistic effect on mortality was demonstrated in a combined infection of mice with murine cytomegalovirus (MCMV) and Pseudomonas aeruginosa, Staphylococcus aureus, or Candida albicans. Mice infected intraperitoneally with a 0 to 20% lethal dose inoculum of MCMV 3 days prior to the intravenous injection of a 0 to 20% lethal dose inoculum of either the bacteria or fungus demonstrated a striking enhancement of mortality. MCMV-infected mice given Pseudomonas or Staphylococcus exhibited a 90 to 100% mortality within 24 to 48 h, whereas 80% of viral-infected animals injected with Candida died in 5 days. Injection of the bacteria or fungus at various times during the MCMV infection resulted in enhanced mortality on days 0,1,2, and 3 of the viral infection. Greatest synergism was observed on day 3, with a progressive decline in death rates thereafter. Immunization with MCMV abrogated the synergistic effect on mortality in all three combined infections. Immunization with Pseudomonas reduced mortality in the combined MCMV-Pseudomonas infection. These results indicate that mice exhibit a markedly enhanced susceptibility to bacterial and fungal infections during the course of the MCMV infection and suggest that the enhancement may be related to viral-induced alterations in host resistance.
Relationship of capsular type to biochemical and immunological properties of teichoic acid preparations from unencapsulated strains of Staphylococcus aureus
Authors: Ohtomo T , Yoshida K , Clemente C L
Published: January 2020

We investigated the biochemical and immunological characteristics of teichoic acid preparations (TAP) obtained from four unencapsulated strains of Staphylococcus aureus which nonetheless, according to the serum-soft agar technique, produced capsular type antigen and were representative of the four types A, B, C, and D. In the agar diffusion test, TAP of each strain produced a single precipitin line only against rabbit antisera corresponding to the homologous capsular type; no lines were observed against antisera to the heterologous capsular type. All TAP were ribitol type except one, glycerol, prepared from a capsular type D strain. Major acetylglucosaminyl residues of TAP from strains having capsular type A and C antigens were attached to the polyribitol phosphate by beta-linkage, whereas TAP from a type B antigen strain had an alpha-linkage; type D antigen was attached to the polyglycerol phosphate by the beta-linkage. Chemical analyses and infrared spectrograms of these TAP further confirmed their heterogeneous nature.
Antisera to human cytomegalovirus produced in hamsters: reactivity in radioimmunoassay and other antibody assay systems
Authors: Forghani B , Schmidt N J , Lennette E H
Published: January 2020

Hamsters immunized with human cytomegalovirus (CMV) concentrated and purified by polyethylene glycol precipitation and density gradient centrifugation produced antisera with high titers of specific viral antibody, and which showed no significant reactivity with human host cell components. The antisera had high titers of CMV antibody in complement fixation, indirect fluorescent-antibody (FA), and neutralization tests, but titers obtained by indirect radioimmunoassay (RIA) were markedly higher. The antisera were used to follow the development of CMV antigen in infected host cells by indirect RIA and indirect FA staining. Virus-specific antigen was first detectable by RIA at 8 h after infection, and by FA staining at 16 h; cells contained optimal amounts of antigen for RIA and FA assays at 72 to 100 h postinfection. Immune globulins from the antisera were labeled with 125I for use in direct RIA. The labeled globulins gave highly specific reactions with CMV-infected cells, including those infected with low-passage isolates, and showed no reactivity with cells infected with other human herpesviruses or certain other human viruses.
Persistence, pathogenesis, and morphology of an L-form of Streptococcus pyogenes adapted to physiological isotonic conditions when in immunosuppressed mice
Authors: Fernandes P B , Panos C
Published: January 2020

Evidence obtained using nonimmunosuppressed and newborn mice suggests that the immune response of the host plays a role in the rapid removal of a physiologically isotonic L-form of Streptococcus pyogenes, since its inability to persist in vivo was not due to osmotic lysis. With mice immunosuppressed with methylprednisolone sodium succinate, viability and detection of this L-form by fluorescent antibody was prolonged for at least 2 weeks, the approximate duration of immunosuppression in these mice. However, heat-killed L-form cells only persisted for 3 days in such mice. Therefore, persistence of a viable L-form in these treated mice was not simply due to the lack of removal of L-forms by a compromised host. At no time was there any indication of illness in nonimmunosuppressed or immunosuppressed mice after L-form injection, and all internal organs, when examined macroscopically, remained normal. Thus, overt pathogenesis was not a characteristic of this L-form in a suitable host even when its immune response had been compromised. The microscopic morphology of the L-form after isolation from immunosuppressed mice changed drastically. It was typically micrococcal in appearance and exemplified the cellular variability achievable by this organism in vivo. Also, streptolysin S production was increased markedly by passage of the L-form in immunosuppressed mice. However, M protein, as a cellular component, was not detected serologically, nor was any reformation of a rigid cell wall apparent by electron microscopy after isolation of this streptococcal L-form from such mice.
Interaction of inflammatory cells and oral microorganisms. II. Modulation of rabbit polymorphonuclear leukocyte hydrolase release by polysaccharides in response to Streptococcus mutans and Streptococcus sanguis
Authors: McArthur W P , Taichman N S
Published: January 2020

The release of lysosomal hydrolases from polymorphonuclear leukocytes (PMNs) has been postulated in the pathogenesis of tissue injury in periodontal disease. In the present study, lysosomal enzyme release was monitored from rabbit peritoneal exudate PMNs exposed to Streptocccus mutans or Streptococcus sanguis. S. mutans grown in brain heart infusion (BHI) broth failed to promote significant PMN enzyme release. S. sanguis grown in BHI broth, although more effective than S. mutants, was a weak stimulus for promotion of PMN hydrolase release. Preincubation of washed, viable S. mutans in sucrose or in different-molecular-weight dextrans resulted in the ability of the organisms to provoke PMN release reactions. This effect could bot be demonstrated with boiled or trypsinized S. mutans or with viable S. sanguis. However, when grown in BHI broth supplemented with sucrose, but not with glucose, both S. mutans and S. sanguis triggered discharge of PMN enzymes. The mechanism(s) whereby dextran or sucrose modulates PMN-bacterial interaction may in some manner be related to promotion of microbial adhesiveness or aggregation by dextran and by bacterial synthesis of glucans from sucrose.
Homologous and heterologous protection of mice with group A streptococcal M protein vaccines
Authors: Wittner M K , Fox E N
Published: January 2020

Purified streptococcal M proteins precipitated with alum (APM) were used to immunize mice. A trivalent vaccine of serotypes 1, 3, and 12 protected mice against challenges by homologous live streptococci and also conferred protection against serotypes 6 and 14 but not against a strain of group B streptococci. Monovalent APM vaccines afforded homologous protection and restricted heterologous protection. The extent of heterologous protection was a function of serotype combinations and was also dose dependent. Rabbit antisera exhibiting strong opsonic activities were active in vitro and in passive mouse protection only for homologous serotypes. Mouse antisera did not passively transfer protection and were not bactericidal in vitro. It was concluded that homologous and heterologous active mouse protection was most likely a result of shared antigenic determinants of the various M proteins although protection of mice could not be measured as a function of circulating anti-M antibodies.
Effects of tobacco smoke on chemotaxis and glucose metabolism of polymorphonuclear leukocytes
Authors: Bridges R B , Kraal J H , Huang L J , Chancellor B M
Published: January 2020

The effect of tobacco smoke on in vitro chemotaxis of human polymorphonuclear leukocytes (PMN) was determined. Whole tobacco smoke, gas phase of smoke, and water-soluble fraction were potent inhibitors of PMN chemotaxis. The results indicated that PMN chemotaxis was inhibited in a dose-dependent manner by water-soluble fraction and that this suppression was not a result of cytotoxicity. In an attempt to determine the mechanism of chemotaxis inhibition, the effect of tobacco smoke on glucose metabolism of PMN was studied. Exposure of PMN to whole smoke, gas phase, or water-soluble fraction resulted in an increase (twofold) in glucose catabolism via both glycolysis and the hexose monophosphate shunt, with no apparent effects on the metabolism of glucose via the tricarboxylic acid cycle. These results suggest that the inhibitory effects of tobacco smoke on PMN chemotaxis were not directly attributable to effects on glucose metabolism of these cells. Further, the inhibitory effects of water-soluble fraction on PMN chemotaxis were shown to be largely irreversible and preventable in the presence of cysteine. Thus, the major inhibitory effects of tobacco smoke probably result from the direct action of oxidants and/or thiol-reactive substances on PMN.
Mechanism of action of Pseudomonas aeruginosa exotoxin Aiadenosine diphosphate-ribosylation of mammalian elongation factor 2 in vitro and in vivo
Authors: Iglewski B H , Liu P V , Kabat D
Published: January 2020

Previous studies showed that Pseudomonas aeruginosa exotoxin A (PA toxin) catalyzes nicotinamide adenine dinucleotide (NAD)-dependent inhibition of protein synthesis in a rabbit reticulocyte lysate and transfer of radioactivity from [14C]adenine-labeled NAD to a protein having the same molecular weight as elongation factor 2 (EF-2) (B.H.Iglewski and D. Kabat, 1975). Such an inhibited protein-synthesizing lysate was restored to activity by addition of a protein from normal mouse liver which co-purifies with EF-2. In addition, EF-2 activity was almost totally absent in livers of mice which had been injected 24 h earlier with PA toxin. On the contrary, EF-2 concentrations were only partially reduced in other organs and were normal in brains of intoxicated mice. Studies using NAD labeled in various positions show that PA toxin, like fragment A of diphtheria toxin, catalyzes transfer of the adenosine 5'-diphosphate-ribosyl moiety of NAD. Furthermore, reversal occurred when the modified protein was incubated with excess concentrations of PA toxin and nicotinamide, and NAD was identified as a product of the reverse reaction. The protein modification catalyzed either by PA toxin or by fragment A of diphtheria toxin could be reversed by incubation with other toxin. These results support the proposal that these two toxins adenosine 5'-diphosphate-ribosylate and same amino acid of EF-2 in a stereochemically identical fashion. Furthermore, PA toxin inactivates EF-2 in intoxicated mice to an extent which would ultimately result in death.
Repetitive counterelectrophoresis on agar gel for the immunological identification of esterases produced by strains of Lancefield's group A, B, and C streptococci
Authors: Hayano S , Tanaka A
Published: January 2020

A method, repetitive counterelectrophoresis (RCE), was devised for detecting specific antibody to streptococcal esterase (STE). Reference antisera were prepared by immunizing rabbits with STE of streptococcal strains as follows: SS379 (group A, type 40), 69882 (group A, type 49), and H36B (group B, type Ib). Some human sera, derived from patients with scarlet fever, were also used as references. By this method, we have confirmed the immunological specificity of the STE produced by strains SS379 (STE-AI), 69882 (STE-AII), H36B (STE-B), and Austin (STE-C, group C) and have shown that the STE produced by strain 10706 (group C) is immunologically identical with STE-AI. Each STE presented a distinct colored line with the respective homologous antibody upon development of enzyme activity except for STE-AII, which formed a round spot with the homologous antibody. Horse activating factor (Hayano and Tanaka, 1973) formed a round spot with each STE. The factor in serum that reacted specifically with STE seemed to correspond to gamma globulin.
Serum opacity factor of Staphylococcus epidermidis
Authors: El Tayeb S H , Nasr E M
Published: January 2020

Three Staphylococcus epidermidis strains produced a factor giving rise to opacity in different sera but not in albumin. Serum opacity factor was resistant to age and heat and active in acidic media.
Host-parasite relationships in the yeastlike form of Paracoccidioides brasiliensis strain IVIC Pb9
Authors: San-Blas G , San-Blas F , Serrano L E
Published: January 2020

The yeastlike form of Paracoccidioides brasiliensis strain IVIC Pb9 reduced the amount of alpha-1,3-glucan in its cell wall from 45 to 3% when subcultured in vitro for several years. This strain regained its alpha-1,3-glucan up to 25% of the total cell wall when grown in vivo. A mutant strain of P. brasiliensis Pb9, named IVIC Pb140, reported to have 1,3-mannan instead of alpha-glucan in the cell wall, could not be recovered from experimentally infected animals. The existence of some relationship between the presence of alpha-1,3-glucan in the cell wall of the yeastlike form and the pathogenicity of this fungus is suggested in this report.