bluuebunny/crossref_metadata_2025 huggingface dataset:
Type-Specific Opsonic Antibodies in Streptococcal Pyoderma
Authors: Bisno Alan L. , Nelson Kenrad E.
Published: January 2020

Prospective studies of streptococcal pyoderma were carried out among black children enrolled in Project Headstart centers in Holmes County, Miss. Sera collected from 28 of these children in early October were tested for opsonic antibodies to one of two prevalent skin strains of group A streptococci isolated from them on one or more occasions over the preceding 3 months. The two streptococcal strains (A and B) belong to M-types previously unrecognized. Ten subjects (36%) had antibody to their homologous serotypes detectable by the indirect bactericidal test: this included 6 of 10 subjects infected with strain B but only 4 of 18 infected with strain A (
P
< 0.05). Of 17 children who had strains A or B isolated from skin lesions only, 12% developed type-specific antibodies (TSA) against the infecting serotype. In contrast, 11 subjects had these strains isolated from throat cultures (either with or without associated pyoderma), and 72% had detectable TSA (
P
< 0.01). There was no demonstrable relationship between the development of antibodies to streptococcal extracellular products or to non-type-specific cellular antigens and the development of TSA. These results demonstrate that type-specific immune responses do occur following infection with pyoderma streptococci. The frequency with which such antibodies develop is variable and appears related to a number of factors, including the immunologic properties of the infecting strain and the site of bacterial colonization. Pharyngeal carriage may represent an important mechanism for development of acquired immunity to skin strains of group A streptococci.
Persistent Infection of BSC-1 Cells by Defective Measles Virus Derived From Subacute Sclerosing Panencephalitis
Authors: Burnstein Theodore , Jacobsen Linda B. , Zeman Wolfgang , Chen Tsu T.
Published: January 2020

A line of cells (IP-3), persistently infected with defective measles virus, was developed from co-cultures of subacute sclerosing panencephalitis-derived brain cells with monkey kidney cells (BSC-1). The line, carried for more than 45 serial passages, produced neither infectious virus nor hemagglutinin. Cultures consistently displayed a cycling focal cytopathic pattern of infection characterized by formation of syncytia, necrosis, and plaques followed by healing. Fluorescent measles antigen was present in damaged areas only, especially in syncytia. The development of syncytia was suppressed by measles antibody. Syncytia were lysed by antibody plus rabbit complement. A variant noncytopathic subline (IP-3-Ca) was derived from the 16th passage. Infectious virus was not detected. Cells were minimally positive for hemadsorption. Fluorescent measles antigen was present in all cells. Co-cultures of IP-3-Ca cells with normal BSC-1 cells developed massive syncytia and extensive destruction. The IP-3-Ca cells multiplied in the presence of measles antibodies and were destroyed by antibodies plus complement. The possible relevance of these findings to the pathogenesis of subacute sclerosing panencephalitis is discussed.
Phase Transition of Gonococci in Mammalian Cell Cultures
Authors: Tyeryar Franklin J. , Quan Alice L. , Rene Anthony A. , Weiss Emilio
Published: January 2020

Neisseria gonorrhoeae
was cultivated in mammalian cell cultures in an effort to determine if this environment will elicit a T4 → T1 transition. Of four avirulent (T4) isolates tested, only one, H4, yielded T1 colonies. This change was consistently obtained in HeLa, WI-38, and MK2 cells, even when the multiplicity of the gonococcal infection was less than 1 per culture. Growth of the gonococci took place primarily on the surface of the cells, as demonstrated by light and electron microscopy, but occasional bacteria were undoubtedly intracellular. T1 colonies were seen at 24 h and were the major population at 48 h. This shift was favored by the presence of viable cells, since smaller yields of T1 were obtained when the cells were irradiated or heat inactivated. It was also favored by low pH, since T1 recovery was reduced when the buffering capacity of the medium was increased. Although the results suggest that T1 gonococci derived from H4 have a selective advantage over T4 in cell cultures, this is not true of all T1 and T4 colony types. F62 T4, which does not undergo a T4 → T1 shift, propagated as well as T1 in HeLa cell cultures. The change in colony type of strain H4 to T1 was accompanied by formation of pili and by gain in capacity for deoxyribonucleic acid-mediated transformation. It is concluded that gonococci can undergo T4 → T1 phase transition in mammalian cell cultures, but this property is not retained by all strains.
Effect of a potent interferon inducer on acute and chronic lactic dehydrogenase virus viremia
Authors: Johnson M L , duBuy H G
Published: January 2020

The effect of a single and multiple doses of polyinosinic-polycytidylic acid (poly (I). poly(C) on lactic dehydrogenase virus viremia has been studied. A single injection of 200 mug of poly (I)-poly(C) given 6 h before infection with lactic dehydrogenase virus caused a temporary decrease in viremia of about 2.5 log10. Repeated injections of 100 mug of poly(I)-poly(C) every 24 h beginning at -24 h caused a temporary decrease in viremia of about 4.0 log 10. Therapeutic treatment with optimal dosage schedules (100 mug every 24 h) caused a reduction in viremia of 1.0 to 2.0 log10. This decrease lasted for at least 24 h after the treatment was stopped. Some possible reasons for the limited effectiveness of poly (I)-poly(C) in this system are discussed.
Suppression of extablished Friend virus leukemia by statolon: potentiation of statolon's leukemosuppressive activity by chlorite-oxidized oxyamylose
Authors: Weislow O S , Wheelock E F
Published: January 2020

Treatment of Friend virus (FV)-infected mice, 3 days after FV inoculation, with statolon, an extract of the mold Penicillium stoloniferum, induces interferon and restores immunocompetence to viral and nonviral antigens such as sheep erythrocytes. Clinical remissions are established in 20 to 70% of the infected mice. Cholorite-oxidized oxyamylose administered intraperitoneally 24 h before, 3 h before, or 3 h after statolon enhanced interferon production, but the increased number of mice protected against FV disease was more closely related to the associated enhanced synthesis of FV cytotoxic antibody. The prolonged selective immunodepression to intraperitoneal sheep erythrocytes after intraperitoneal administration of chlorite-oxidized oxyamylose-statolon appeared to be related to a stimulation in number and erythrocyte-phagocytic capacity of peritoneal macrophages. The marked activation of macrophages in FV leukemic mice after such treatment may also have contributed to the enhanced FV leukemosuppressive effects of chlorite-oxidized oxyamylose-statolon.
Characterization of an in vitro persistent-state measles virus infection: establishment and virological characterization of the BGM/MV cell line
Authors: Menna J H , Collins A R , Flanagan T D
Published: January 2020

The parameters of a persistent-state measles virus infection in BGM/MV cells were examined. The BGM/MV cell line was established by cocultivation of measles virus-infected primary C3H mouse brain cells with a stable line of African green monkey kidney cells (BGM). Initially, a morphologically mixed population of cells existed:BGM-like (epithelioid) and fibroblasts. Gradually the fibroblasts were replaced by BGM-like cells, resulting in a morphologically homogeneous population. Measles cytopathic effect was noted 2 days after initiation of this culture and persisted for approximately 290 days. The time of disappearance of viral cytopathic effect corresponded to the time at which morphological homogeneity was reached. Low titers of infectious measles virus were detected in the BGM/MV culture up to 20 days postseeding; thereafter none was observed. After 440 days in culture, 100% of BGM/MV cells demonstrated intractyoplasmic measles antigen by immunofluorescence. Nuclear fluorescence was never observed. Electron microscopy revealed the presence of measles virus mucleocapsid within the almost completely filling the cytoplasm of BGM/MV cells. The plasma membrane of these cells appeared normal; no maturing or budding particles were observed. Measles virus hemagglutinin was not detected in either clarified cell lysates or in supernatant culture fluids. Cell membrane alteration by measles virus was detected in less than 1% of these cells by hemadsorption and by membrane immunofluorescence. The hemadsorption activity of the cells could be enhanced (30 to 70%) by treatment with actinomycin D or enucleation with cytochalasin B; these treatments, however, were unsuccessful in inducing detectable levels of measles hemagglutinin. Treatment of BGM/MV cells with 5-bromo-2'-deoxyuridine (BUdR) at 5 to 50 mug/ml and cytosine arabinoside at 1 to 50 mug/ml failed to enhance hemadsorption activity. Doses of 5-bromo-2'-deoxyuridine ranging from 5 to 200 mug/ml and of actinomycin D ranging from 0.1 to 10 mug/ml were ineffective in inducing the synthesis of infectious virus. Various physical methods of induction of infectious virus was also unsuccessful.
Pathophysiology of infectious hematopoietic necrosis virus disease in rainbow trout: hematological and blood chemical changes in moribund fish
Authors: Amend D F , Smith L
Published: January 2020

Infectious hematopoietic necrosis (IHN) is a rhabdoviral disease of rainbow trout (Salmo gairdneri). Trout were injected with IHNV, and various hematological and biochemical measurements of clinically ill fish were compared to uninfected controls. Infected fish had reduced corpuscular counts, hemoglobin, and packed cell volume, but normal mean corpuscular volume, mean corpuscular hemoglobulin, and mean corpuscular hemoglobin concentration. The percentage of immature erythrocytes was increased, but the percentage of leukocytes was unchanged. Differential leukocyte counts showed a significant decrease in neutrophils, increase in lymphocytes, but no change in monocytes. Unidentifiable necrobiotic cells were prevelant in blood smears and hematopoietic tissue imprints. Plasma bicarbonate, chloride, calcium, phosphorus, bilirubin, and osmolality were signigicantly reduced, but plasma glucose and anterior kidney ascorbate were unchanged. Plasma pH increased and the alpha fractions of the serum proteins were altered. No change was found in plasma enzymes, except that a LDH isozyme was significantly increased. The alkali reserve was diminished and alterations in acid-base and fluid balance occurred. Death probably resulted from a severe electrolyte and fluid imbalance caused by renal failure.
Variations in properties of L-forms of Pseudomonas aeruginosa
Authors: Bertolani R , Elberg S S , Ralston D
Published: January 2020

In a study of the pathogenic potentials of Pseudomonas L-forms, three unstable L-forms were derived by carbenicillin inductionfrom a mouse virulent strain of Pseudomonas aeruginosa, Rosenthal 180. One L-form, induced on a sucrose-stabilized medium, grew more slowly and differed in a number of properties from two other L-forms induced on a medium supported with polyvinylpyrilidone. After adaptation to a common liquid medium, the three L-forms differed with respect to colonial shape on solid medium, growth rate, certain biochemical properties, antibiotic sensitivities and antigenic surface, and virulence for mice. The L-form may revert in vitro to a serotype different from that of the parent culture. The revertant may acquire new antibiotic resistances and sensitivities in the absence of previous exposure to the drugs and enhanced resistance to the L-inducing agent. The three L-forms showed a characteristically lower, but wide, range of virulence than did the parental form. Though death of mice was accompanied by reversion of the L-forms in vivo to the bacterial form, reversion in vivo was not necessary for virulence of L-forms. Modification of residual cell wall antigens accompanied the induction of each L-form as determined by type-specific antisera.
Immunoelectron microscopic identification and localization of Streptococcus sanguis with peroxidase-labeled antibody: localization of surface antigens in pure cultures
Authors: Lai C H , Listgarten M A , Rosan B
Published: January 2020

An indirect method of localizing antigens with horseradish peroxidase-labeled antibody was used to identify and localize surface antigens of Streptococcus sanguis at the ultrastructural level. An electron dense layer surrounding the cell wall could be distinguished without any additional electron microscope staining. This labeled layer represents an immune complex consisting of bacterial surface antigens, specific rabbit antisera, and peroxidase-labeled goat anti-rabbit globulins. Although with undiluted antisera slight cross-reactions occurred with S. salivarius and S. miteor (mitis), these could be readily distinguished from the more intense homologous reaction by their patchiness and the difference in distribution of the label. These cross-reactions were eliminated by appropriate dilutions of the antiserum. No cross-reactions occurred with S. mutans, S. faecalis, Actinomyces species, or Bacterionema, microorganisms wents indicated that horseradish peroxidase can become non-specifically adsorbed to the membrane of certain bacterial cells. Appropriate controls must, therefore, be included for localization of membrane associated antigens with horseradish peroxidase.
Immunoelectron microscopic identification and localization of Streptococcus sanguis with peroxidase-labeled antibody: localization of Streptococcus sanguis in intact dental plaque
Authors: Lai C H , Listgarten M A , Rosan B
Published: January 2020

Streptococcus sanguis has been localized ultrastructurally within intact dental plaque by means of an indirect technique which utilizes horseradish peroxidase-labeled antibody. The technique allows for complete diffusion of the reagents to all portions of the plaque specimens. Control procedures can be carried out on serial sections of plaque with a bacterial composition similar to that of the experimental specimen. The 30-mum-thick sections can be examined in the light microscope to localize areas specifically labeled with peroxidase prior to cutting ultra-thin sections for electron microscopy. This study demonstrated that specific bacteria can be localized within intact dental plaque. The results also indicated that S. sanguis grows in dental plaque as columnar shaped microcolonies perpendicular to the tooth surfaces. Growth appears to be by cell division rather than deposition of new cells at the surfaces. Despite their relatively good structural preservation, the cells in the deeper (older) layers of plaque appear to have lost some of their antigenic activity in comparison to the cells near the surface.
Regional immunosuppression induced by Plasmodium berghei yoelii infection in mice
Authors: Wiedanz W P , Rank R G
Published: January 2020

Plasmodium berghei yoelii infection in mice severely depressed the splenic antibody response to sheep erythrocytes but had lettle effect on antibody formation in lymph nodes.
Coccidioidin and merthiolate in previously sensitized animals
Authors: Flynt P L , Sinski J T , Kelley L M
Published: January 2020

The effect of merthiolate, which is used as a preservative in skin test materials, on skin test reactions was determined in guinea pigs. In four groups of animals, merthiolate in basal medium produced skin tests at 24 and 48 h characterized by erythema and/or induration in an intermediate region, i.e., 5 plus or minus 2.2 mm. One of the four groups of animals was a nonsensitized control group. The other three groups were subcutaneously sensitized with (i) merthiolate and saline, (ii) killed Coccidioides immitis arthrospores, and (iii) merthiolate with killed C. immitis arthrospores. Coccidioidin only and merthiolate in coccidioidin produced positive delayed results in groups 3 and 4, which were sensitized with arthrospores. A synergistic effect of merthiolate and coccidioidin was observed in animals of group 4 sensitized by merthiolate with killed C. immitis arthrospores. This effect was observed at 24 h when positive reactions of coccidioidin with merthiolate were significantly greater than skin tests with plain coccidioidin.
Effect of Corynebacterium acnes on interferon production in mouse peritoneal exudate cells
Authors: Fischbach J , Glasgow L A
Published: January 2020

Corynebacterium acnes, an organism closely related to C. parvum, has been recognized to have a striking effect on the reticuloendothelial system, as well as on both humoral and cellular immunity. In mice previously exposed to C. acnes, serum interferon levels induced by injection of Newcastle disease virus (NDV), Chikungunya virus (CV), and polyinosinic-polycytidylic acid are suppressed. When peritoneal macrophages and lymphocytes from animals exposed to C. acnes were cultivated in vitro, their capacity to produce interferon in response to NDV and CV was reduced. Furthermore, the interferon-producing capacity of these cells in tissue culture was inhibited after exposure to C. acnes to vitro. Exposure of separated populations of peritoneal macrophages and lymphocytes to C. acnes in vitro demonstrated that the interferon response to NDV by both cell types is inhibited. Peritoneal macrophages appear to be the major contributor to the interferon response in this system. Finally, this inhibitory effect was shown to occur after exposure to a purified cell wall preparation of C. acnes organisms, as well as a lipid extract of this preparation.
Bovine veneral vibriosis: cure of genital infection in females by systemic immunization
Authors: Schurig G G , Hall C E , Corbell L B , Duncan J R , Winter A J
Published: January 2020

Cure of female cattle with venereal vibriosis by systemic immunization with killed Campylobacter fetus cells in incomplete Freund adjuvant was investigated. Heifers infected in the cervicovaginal area with a cloned population of C. fetus venerealis were vaccinated subcutaneously 14 and 24 days thereafter with the infecting strain in incomplete Freund adjuvant. Six of eight vaccinated heifers were free of infection 25 to 48 days postinfection. One of the cured animals had an intercurrent infection which precluded interpretation of a vaccine effect. All controls remained infected 48 to 51 days postinfection, when the experiment was terminated. In vaccinated animals, agglutination titers against whole cells of the infecting strain reached peaks varying from 1,280 to 20,480 in serum and from 20 to 5,120 in cervicovaginal mucus (CVM) within days 24 to 32 postinfection. No consistent relationship was noted between levels of whole cell antibodies in serum and those in CVM. Evidence for the occurrence of antigenic variation in the organism after vaccination was sought by comparing the agglutinability of the infecting strain and CVM isolates in serum and CVM extracts. Serum samples of most cured heifers agglutinated whole cells prepared from isolates of the respective heifers to the same extent as cells of the infecting strain. In the corresponding comparisons, those from noncured animals agglutinated isolates to lower titers. CVM extracts from one cured animals agglutinated isolates derived from the same or closely spaced CVM samples to titers comparable with those obtained with the infecting strain. In the remaining animals, CVM extracts which agglutinated the infecting strain produced lower or undetectable reactions with corresponding isolates. It is proposed that the elimination of infection is dependent upon opposing responses of host and parasite, of which the degree of antigenic alteration in the infecting strain and the rate of mobilization and the concentration of specific antibodies in the genital secretions are key factors.
Influence of cell type and virus upon virus-specific immune cytolysis
Authors: Brandt W E , Russell P K
Published: January 2020

Immune cytolysis was measured by release of absorbed radioactive chromium from infected cells that were incubated with antiviral antibody and complement. The presence of virus-specific antigens detected in this manner on the surface of several types of cells infected with Japanese encephalitis (JE) virus did not correlate in each instance with the maturation of infectious virus. JE-infected LLC-MK-2 and Vero cells could not be lysed until long after the first appearance of released virus, and the lysis was minimal in that only a small amount of chromium was released. However, JE-infected BHK-21 and chicken embryo cells could be lysed as soon as new virus was detected in the culture medium, and the lysis reached maximum levels before the time that maximum levels of infectious virus were found in the culture fluids. This phenomenon was restricted to JE virus since BHK-21 cells infected with dengue-2 virus (another group B arbovirus) could not be lysed until well after the appearance of new virus in the culture medium.
Studies on gonococcus infection. VIII. 125Iodine labeling of gonococci and studies on their in vitro interactions with eukaryotic cells
Authors: Swanson J , King G , Zeligs B
Published: January 2020

Intact gonococci (GC) have been labeled with 125iodine by the lactoperoxidase plus hydrogen peroxide procedure. The specific activities of types 2, 4, and 4 GC have been determined and are found to show small differences as follows: T4 greater than T2 greater than T4. 125I-labeled GC have been studied for their associations with both leukocytes and tissue culture cells. 125I-labeled GCshow the following relative order of association with the leukocytes: T2 equals T4* greater than T4. This contrasts with the relative degree of interaction between the GC and tissue culture cells, which follows the relative order: T2 greater than T4 equals T4*. Trypsin pretreatment of GC markedly reduces the association of all three types (T2, T4 AND T4*) with leukocytes but does not alter the level of attachment of any of the gonococcal types with tissue culture cells.
Temporal appearance of opsonizing antibody to Francisella tularensis: detection by a radiometabolic assay
Authors: Canonico P G , McManus A T , Mangiafico J A , Sammons L S , McGann V G , Dangerfield H G
Published: January 2020

The burst in oxidative metabolism that is mediated through activation of the hexose monophosphate shunt and accompanies particle ingestion by polymorphonuclear leukocytes was used as the indicator in an in vitro radiometabolic assay for detection of specific opsonizing antibody to Francisella tularensis. Release of 14CO2 from radiolabeled glucose was increased significantly when specific immune serum added to suspensions of monkey polymorphonuclear leukocytes and F. tularensis. With this method, opsonizing antibodies to F. tularensis were detected in monkey serum 3 days after vaccination. Significantly increased opsonic activity in these monkeys preceded the appearance of, and persisted longer than, antibody activity as determined by conventional serological techniques. In addition, sera from 11 of 12 humans that were immunized 1 month to 13 years previously and had nondiagnostic agglutinating antibody titers demonstrated significant opsonizing activity.
Genital herpesvirus hominis infection in mice. I. Development of an experimental model
Authors: Overall J C , Kern E R , Schlitzer R L , Friedman S B , Glasgow L A
Published: January 2020

Pregnant female mice, after intravaginal inoculation with Herpesvirus hominis (HVH) type 2, developed vaginitis on days 5 to 7 after virus challenge, followed by hunching and hind limb paralysis on days 7 to 9 and death from encephalitis on days 9 to 11. After initial replication in the mucous membranes of the genital tract, virus spread to the spinal cord and ascended to involve the brain. Viremia or replication of H. hominis type 2 in the liver or spleen was not detected. Virus was cleared from vaginal secretions by days 8 to 10 after infection. Pregnant mice were more susceptible to the infection than nonpregnant mice. This experimental infection in female mice provides a model for genital herpesvirus infection and for herpesvirus infection and for herpesvirus encephalitis in which one can evaluate potentially promising antiviral chemotherapeutic agents.
Calf ligated intestinal segment test to detect enterotoxigenic Escherichia coli
Authors: Myers L L , Newman F S , Warren G R , Catlin J E , Anderson C K
Published: January 2020

The ligated intestinal segment test in the young calf was utilized to establish the enterotoxigenicity of approximately 600 Escherichia coli isolates obtained from fecal specimens intestinal contents of calves with diarrheal disease. One hundred and fifty isolates were routinely tested in a single calf. There was little problem with false-positive reactions. False-negative reactions normally occurred only if the isolate was tested in the posterior 3 m of the small intestine. The ligated small intestine of the calf was distended by E. coli isolates of bovine, porcine, and human origin. Use of the calf ligated intestinal segment test is recommended to determine the enterotoxigenicity of E. coli isolates of bovine origin.
Stimulation of phagocytic activity in the reticuloendothelial systems of mice by lipid A complexed with homologous or heterologous proteins
Authors: Nakano M , Asou H , Yamamoto I
Published: January 2020

Heterologous proteins are more suitable carriers than homologous proteins for the expression of endotoxic activity of lipid A prepared from the lipopolysaccharides of Salmonella typhimurium SL1102 (Re form) to stimulate the reticuloendothelial system of mice.
Reactions of purified hemagglutinating antigens of flaviviruses with 19S and 7S antibodies
Authors: Westaway E G , Shew M , Della-Porta A J
Published: January 2020

The rapidly sedimenting hemagglutinin (RHA) representing the purified virion and the slower-sedimenting hemagglutinin (SHA) of several flaviviruses were separated and used in hemagglutination inhibition tests with the 19S (immunoglobulin M) and 7S (immunoglobulin G) immunoglobulin fractions of rabbit antisera, prepared against purified viral antigens or against crude virus pools. The antibody specificity in tests with RHA was identical to the specificity in those employing SHA. 7S antibody cross-reacted broadly with all flavivirus antigens, whereas 19S antibodies were relatively specific in cross-reactions among flaviviruses (RHA or SHA). SHA was consistently inhibited by antibody to a greater extent than RHA. Anti-envelope protein, anti-RHA antibodies and anti-SHA antibodies were unable to discriminate between RHA and SHA. It was concluded that the relative amounts of RHA or SHA in crude hemagglutinin preparations have no influence on the result of hemagglutination inhibition tests with flaviviruses.
Determination of toxin-induced leakage of different-size nucleotides through the plasma membrane of human diploid fibroblasts
Authors: Thelestam M , Möllby R
Published: January 2020

Human diploid lung fibroblasts were treated with cytolytic bacterial toxins and the nature of the membrane damage was investigated. [3H] uridine was used for differential labeling of cytoplasmic components of small or large molecular size. Two principal size categories were achieved by labeling the fibroblasts in either early growth phase or stationary phase, a high-molecular weight ribonucleic acid label and a low-molecular-weight nucleotide label. The size of the labeled molecules was determined by perchloric acid precipitation and gel chromatography. Leakage of labeled molecules of different size indicated the size of the "functional pores" in the plasma membrane caused by the test substance. The nonionic detergent Triton X-100 produced large functional pores in the fibroblast membrane as evidenced by rapid leakage of both large and small labeled molecules. Theta-toxin from Clostridium perfringens and the polyene antibiotic filipin both gave rise to considerably small functional pores in the plasma membrane. Although small molecules easily passed the treated membrane, large molecules could not escape from the cells even after prolonged treatment with these substances or by increasing their concentration. By the contrast, the leakage profiles obtained with melittin from bee venom or with delta-toxin from Staphylococcus aureus in each case suggested the formation initially of pores of intermediate size that increased upon prolonged incubation or when higher concentrations were used.
Growth of several cariogenic strains of oral streptococci in a chemically defined medium
Authors: Terleckyj B , Willett N P , Shockman G D
Published: January 2020

A chemically defined medium in which Streptococcus mutans strains AHT, BHT, GS-5, JC-2, Ingbritt, At6T, At9T, 6715, and OMZ-176 and Streptococcus salivarius strain HHT grew rapidly to high turbidities was formulated. Maximal turbidities of each strain were observed after 8 to 12 h of aerobic growth. The subsequent transfer of exponentially growing cells into fresh medium resulted in growth at the same rate without lag. Growth of these strains occurred with rates at least one-half of those observed in an organic medium, such as Todd-Hewitt broth. S. mutans strains FA-1 and OMZ-61 grew at relatively slow rates in the defined medium, but more rapidly growth to higher turbidities of both strains was obtained when sodium bicarbonate was added to the medium. Streptococcus sanguis strain OMZ-9 and another group H streptococcus (strain 72 times 46) grew rapidly in the defined medium after the addition of sodium carbonate. The presence of carbonate or bicarbonate yielded higher turbidities of all the other strains, and the growth rates of several of the strains tested were also increased.
Amino acid requirements of Streptococcus mutans and other oral streptococci
Authors: Terleckyj B , Shockman G D
Published: January 2020

The amino acid requirements of Streptococcus mutans strains AHT, OMZ-61, FA-1, BHT, GS-5, JC-2, Ingbritt, At6T, OMZ-176, 6715, Streptococcus salivarius HHT, Streptococcus sanguis OMZ-9, and strain 72x46 were determined in a chemically defined medium. When grown anaerobically in the presence of sodium carbonate (or bicarbonate for a few strains), few amino acids were required. All strains tested required cystine (or cystine) as a nutrient. Three strains (S. mutans OMZ-176, FA-1, and BHT) required glutamate (and/or glutamine). A third amino acid (lysine for S. mutans FA-1 and histidine for S. mutans OMZ-176) was required by two of the three strains which required glutamate. The amino acids mentioned above were required for all conditions of incubation (and inoculum) tested. The requirements for several other amino acids were conditional, that is, dependent on the incubation conditions and inoculum used. For example, when carbonate was not added, glutamate was required by S. mutans GS-5. Aerobic incubations, with carbonate or bicarbonate added, resluted in requirements for glutamate and leucine by several strains. With these incubation conditions, one strain required isoleucine (S. mutans FA-1), another valine (S. mutans AHT), and a third tyrosine (72x46). Aerobic incubations in the absence of carbonate or bicarbonate further increased the number of amino acids required by several strains. Furthermore, when stationary-phase cultures replaced exponentially growing cultures as an inoculum, several strains required additional amino acids, presumably for the initiation of growth.
Lymphocyte responses to rubella antigen and phytohemagglutinin after administration of the RA 27/3 strain of live attenuated rubella vaccine
Authors: Vesikari T , Buimovici-Klein E
Published: January 2020

Lymphocyte phytohemagglutinin (PHA) responsiveness was found suppressed in both rubella sero-negative and sero-positive recipients of RA 27/3 strain of live attenuated rubella vaccine; the suppression was readily demonstrable only when a suboptimal dose of PHA was applied in the test. Lymphocytes from sero-negative vaccinees, which initially showed little or no in vitro response to concentrated rubella virus, became responsive after vaccination by day 21, when the highest sensitization to rubella antigen was seen. In the sero-positive vaccinees. lymphocytes responded to rubella antigen in vitro before vaccination, and in most cases vaccination did not result in significant changes in lymphocyte response. These results suggest that rubella vaccination leads to temporarily increased lymphocyte reactivity to rubella antigen, and the increased lymphocyte response to specific antigen may occur at the time of mild suppression of PHA response.
Evaluation of a live, attenuated recombinant influenza vaccine in high school children
Authors: Schiff G M , Linnemann C C , shea L , Lange B , Rotte T
Published: January 2020

A live, attenuated, recombinant influenza vaccine (Alice strain) administered intranasally was evaluated in high school students and compared with intranasal placebo and subcutaneous, inactivated, bivalent influenza vaccine. The Alice strain was antigenic, increasing the geometric mean titer (GMT) from a prestudy level of 30.2 to a postvaccine level of 189.6. The inactivated vaccine increased the GMT from 32.9 to 361.8. There was no increase in the GMT among the placebo recipients. The Alice strain produced little reaction. With an antigenic, safe, acceptable, live, attenuated influenza vaccine available, immunization on a widespread basis should be considered.
Comparative studies of Visna and Maedi viruses as antigens
Authors: Mehta P D , Thormar H
Published: January 2020

Rabbits were immunized with purified visna and maedi viruses, using complete Freund adjuvant, in footpad and intramuscular sites. The resulting antisera and their isolated immunoglobulin G (IgG) and M (IgM) classes were evaluated by tanned-cell passive hemagglutination (PHA), complement fixation, gel diffusion, and virus neutralization tests. Early, intermediate, and late bleedings showed increasingly high antibody activities by the PHA, complement fixation, and gel diffusion tests. The activities were associated mainly with the IgG class, although low, but significant activities were also found in the IgM class, as detected by PHA and complement fixation tests. Both antibody classes appeared at the same time during the course of immunization. The viruses, when tested against specific rabbit anti-visna and anti-maedi sera in gel diffusion tests, showed the presence of one to two precipitin lines depending upon the antibody concentration of the sera. A low amount of neutralizing activity was demonstrated in late bleedings but was not seen in earlier bleedings. The neutralizing activity against visna virus in immunized rabbit sera was found to be associated only with the IgG class. Visna and maedi viruses appeared to be immunologically identical when examined in gel diffusion tests and showed the same degree of inhibition when compared in passive hemagglutination inhibition test using antisera made specific for each virus.
Interactions between Toxoplasma gondii and its host cells: function of the penetration-enhancing factor of toxoplasma
Authors: Lycke E , Carlberg K , Norrby R
Published: January 2020

A protein with a molecular weight of 70,000 to 150,000 which was extracted from merozoites of Toxoplasma gondii enhanced the host cell penetration of the merozoites. The optimal pH and temperature for penetration of merozoites coincided with those favoring the action of the penetration-enhancing protein. In addition, a dependence on Ca and Mg existed for penetration of merozoites, either in the presence or absence of this protein. No evidence was found that indicated that the enhancing effect on penetration elicited by the protein was due to increased phagocytic capacity of host cells (HeLa) or improved motility of the merozoites. Electron microscopy demonstrated that the protein, in high concentration, caused disruption of cytoplasmic membranes. In a 100-fold-lower concentration, which still caused a marked enhancement of penetration, no such effect was observed. However, the vacuoles surrounding the penetrated parasites seemed smaller than for merozoites penetrating in cultures to which no penetration-enhancing factor was given, and the membranes limiting the vacuoles demonstrated discontinuities more often. The penetration-enchancing effect of some known enzymes was studies. However, none of these enzymes seemed to correspond to the penetration-enhancing protein of toxoplasma. The mode of entry of toxoplasma merozoites into host cells is discussed. It is concluded that phagocytosis must play a less important role and that merozoites actively penetrate the cytoplasmic membranes of the host cells. The penetration is proposed to be a result of combined mechanical and chemical actions. It is suggested that an enzymatic function of the penetration-enhancing factor released by the merozoites is of importance. The membrane limiting the vacuole of a penetrated merozoite seems to be newly formed in the cell after penetration is completed.
Growth and immunogenicity of photochromogenic strains of mycobacteria in the footpads of normal mice
Authors: Collins F M , Montalbine V , Morrison N E
Published: January 2020

Specific pathogen-free CD-1 mice were infected subcutaneously in the footpad with mycobacterium kansasii, three strains of M. marinum, and two strains of M. simiae-habana, and the growth of the organisms in the footpad, the draining popliteal lymph node, and the lung and spleen was followed quantitatively for up to 60 days. The ability of a footpad inoculum of M. marinum to spread to the lungs and spleen correlated with the ability of the organism to survive and multiple at 37 C in vitro cultures. The amount of footpad swelling which developed in the M. kansasii- and M. marinum-infected mice varied depending upon the strain of organism and the size of the original footpad inoculum. Injection of dead M. marinum into the footpad also induced an extensive amount of swelling which varied with the strain used, as well as being dose dependent. M. marinum- and BCG-vaccinated mice were protected against a later footpad challenge with M. marinum or the highly mouse virulent M. tuberculosis strain ERDMAN. The significance of this finding is discussed in relation to cross-protection studies using a variety of mycobacteria in the footpad infection model.
Theiler's virus infection in mice: an unusual biphasic disease process leading to demyelination
Authors: Lipton H L
Published: January 2020

An unusual biphasic central nervous system disease developed in 3-week-old Swiss outbred mice after intracerebral inoculation of the DA strain of Theiler's murine encephalomyelitis virus. Nine to 20 days postinfection 86% of mice became paralyzed, and approximately one-half of these animals survived. During this period neuronal necrosis and microglial proliferation were seen in thalamus, brainstem, and spinal cord. There was an initial phase of virus growth in spinal cord followed by persistent infection at a lower concentration. Virus antigen was readily found in the cytoplasm of neurons by immunofluorescent staining early in the course of infection, whereas after 30 days there was a paucity of cells containing virus antigen which were present only in the spinal cord white matter. Between 1 and 5 months, an intense mononuclear inflammatory cell lesion evolved in the spinal cord leptomeninges and white matter, which coincided with a mild gait disturbance in some surviving mice, and patchy demyelination was found in areas of inflammation. The acute gray matter pathology would appear to be the result of direct virus lytic effect. Although the late white matter lesion culminating in demyelination probably represents a cytocidal infection similar to the situation that exists in certain picornavirus carrier culture systems, a virus-induced immunopathological process merits further study.
Strain-specific virulence-associated antigen of Neisseria gonorrhoeae
Authors: Pierce W A , Leong J K , Hough D M
Published: January 2020

A strain-specific virulence-associated antigen has been found in Neisseria gonorrhoeae strain F-62. Using immunodiffusion in agar gel, it has been shown that the antigen is distinguishable from endotoxin and the virulence-associated toxic protein. It does not appear to be derived from pili. The antigen was not detected in T1 and/or T2 colony type cultures of 10 other isolates. It exhibited a possible partial immunological relationship with an antigen found in one additional strain. It was susceptible to digestion with Pronase and trypsin.
Serotyping of Chlamydia: isolates of bovine origin
Authors: Schachter J , Banks J , Sugg N , Sung M , Storz J , Meyer K F
Published: January 2020

Chlamydial isolates of bovine origin were serotyped by a plaque reduction method. Of the two major serotypes observed, type 1 included isolates from bovine abortion and enteric infections, whereas type 2 isolates were associated with polyarthritis or encephalomyelitis. These two serotypes were identical to those with a similar disease distribution previously observed in isolates of ovine origin. The two groups did not cross-react and they were serologically unrelated to chlamydiae of avian origin. Thus, it appears that many chlamydial isolates causing intestinal infections or abortion in sheep or cattle are closely related antigenically, as are those producing polyarthritis, encephalomyelitis, and conjunctivitis, and that the two groups are distinct.
In Vitro Lymphocyte Response to Purified Protein Derivative, BCG, and
Mycobacterium leprae
in a Population Not Exposed to Leprosy
Authors: Closs Otto
Published: January 2020

Lymphocytes from 14 BCG-vaccinated donors, seven tuberculin positive and seven tuberculin negative by skin testing, were stimulated in vitro with four mycobacterial antigens, purified protein derivative (PPD), PPD/BCG, whole BCG bacilli, and whole
Mycobacterium leprae
and also with
Candida
antigen and phytohemagglutinin. The response was measured by incorporation of
3
H-labeled thymidine. The response to PPD, PPD/BCG, and BCG was found to correlate with the result of skin testing with turberculin. The turberculin-positive group also responded more strongly to
M. leprae
, whereas the two groups did not differ significantly in their response to
Candida
antigen or phytohemagglutinin. These findings indicate a certain degree of cross-reactivity between BCG and
M. leprae
. The use of the lymphocyte transformation test to measure antigenic cross-reactivity is discussed.
Immunological Properties of
Rickettsia rickettsii
Purified by Zonal Centrifugation
Authors: Anacker R. L. , Gerloff R. K. , Thomas L. A. , Mann R. E. , Bickel W. D.
Published: January 2020

The properties of
Rickettsia rickettsii
purified from infected chicken yolk sacs or mouse L cell cultures by sucrose density gradient centrifugation in a zonal rotor were examined in various ways. Rickettsiae derived from both L cells and yolk sacs had similar compositions: about 12% nitrogen, 1.5% phosphorus, 5% carbohydrate, and 30% fatty acids. On a dry-weight basis, purified rickettsiae were at least 2,000 times as effective as a commercial spotted fever vaccine in protecting guinea pigs against infection with spotted fever rickettsiae and mice against death from toxin of
R. rickettsii.
Gradient-purified rickettsiae (0.6 μg) induced a serological response in guinea pigs of the same magnitude as that stimulated by 1,600 μg of the commercial vaccine. Gradient-purified rickettsiae had little group reactivity in complement fixation tests but became anti-complementary upon storage. Microagglutination and hemagglutination tests with the purified antigen gave promise of usefulness in diagnosis of spotted fever. These results suggest that zonal centrifugation may be a valuable procedure for the preparation of
R. rickettsii
vaccine and diagnostic reagent.
Lactoperoxidase Activity in Human Milk and in Saliva of Newborn Infants
Authors: Gothefors Leif , Marklund Stefan
Published: January 2020

Human milk and saliva from newborn infants were analyzed for their content of lactoperoxidase and thiocyanate. The activity of lactoperoxidase in infant saliva was variable but generally higher than that found in calf saliva. In contrast, the activity in human colostrum was low (∼5%) compared with that found in cow's milk. The enzyme was resistant to gastric juice. Thiocyanate was demonstrated in infant saliva in concentrations about one-third of that in adult saliva. The amounts of lactoperoxidase and thiocyanate in infant saliva are quite sufficient to inhibit bacterial growth in in vitro systems. The importance of this system in vivo has not yet been demonstrated. The availability of this system to both newborn calves and humans (in calves provided largely by colostrum and in human babies by saliva) might be indirect evidence of its importance.
Function of the Classical and Alternate Pathways of Human Complement in Serum Treated with Ethylene Glycol Tetraacetic Acid and MgCl
2
-Ethylene Glycol Tetraacetic Acid
Authors: Des Prez R. M. , Bryan C. S. , Hawiger J. , Colley D. G.
Published: January 2020

An immunochemical and functional analysis of the classical and alternate complement pathways in human serum was performed in the presence of 10 mM ethylene glycol tetraacetic acid (EGTA) and MgCl
2
-EGTA (MgEGTA), chelating agents which have been recently utilized as a means of distinguishing between these two complement pathways. Total hemolytic activity, integrity of the C1 complex, hemolytic activity of C2, conversion of factor B (C3 proactivator), and complement-dependent bactericidal activity were studied. The effect of these chelators on activation of complement pathways by
Escherichia coli
, by sensitized erythrocytes as a prototype of activators of the classical pathway, and by zymosan as a prototype of alternate (properdin) pathway activators was studied. Human serum containing 10 mM EGTA, which provides almost no ionized calcium and considerably less ionized magnesium than unchelated serum, allowed consumption of complement via the alternate (properdin) pathway, but blocked the classical pathway as judged by disintegration of the C1 complex and lack of utilization of C2. However, activity of the alternate complement pathway in EGTA serum, as judged by conversion of factor B and bactericidal activity against gram-negative bacteria, was distinctly suboptimal. Addition of magnesium ion in a concentration equimolar to EGTA (MgEGTA serum), while still providing conditions in which the C1 complex dissociated, significantly enhanced alternate complement pathway-mediated bactericidal activity. However, in MgEGTA serum considerable fluid-phase activation of the alternate pathway, as indicated by decrease in 50% hemolytic complement (CH
5 0
) titers and conversion of factor B to its active form in the absence of any activating challenge, was observed. Moreover, some fluid-phase consumption of C2 was observed in MgEGTA serum, even though, as mentioned, the C1 complex was shown to be dissociated under these conditions. MgEGTA-related activation of C2 and of the alternate (properdin) pathway of complement was significantly enhanced by the presence of zymosan and
E. coli
. These results indicate that use of the chelating agents EGTA and MgEGTA to differentiate between classical and alternate pathway activation of human complement is more complex than has hitherto been suggested. In EGTA serum, spontaneous activation of either pathway does not occur but bactericidal activity, as a measure of biologic function of complement, is suboptimal. In MgEGTA serum, bactericidal activity is fully expressed, but there is considerable instability, in terms of fluid-phase activation, in Mg
2+
-dependent components of both pathways. Thus, caution is indicated in the use and interpretation of the effects of these chelating agents on biologic functions mediated by either pathway of human complement.