bluuebunny/crossref_metadata_2025 huggingface dataset:
A neuraminidase from Streptococcus pneumoniae has the features of a surface protein
Authors: Cámara M , Boulnois G J , Andrew P W , Mitchell T J
Published: January 2020

A gene from Streptococcus pneumoniae (nanA), with features entirely consistent with a neuraminidase gene, has been sequenced. High levels of neuraminidase activity were obtained after cloning of this gene, without flanking sequences, into a high-expression vector. RNA hybridization studies have shown that the gene is transcribed by a virulent pneumococcus strain. The predicted molecular weight of the protein and certain amino acid sequences are typical of other neuraminidases. NanA contains the four copies of the sequence SXDXGXTW that is present in all the bacterial neuraminidases previously described. Kyte and Doolittle analysis showed that NanA is a hydrophilic protein with hydrophobic domains at the N terminus and the C terminus. A putative signal peptide was found in the N terminus of this protein, indicating that the protein is exported from the pneumococcus. The C terminus has the features of the anchor motif found in other surface proteins from gram-positive bacteria. Electron microscopy studies showed the presence of neuraminidase associated with the cell surface of the pneumococcus.
Mapping of bactericidal epitopes on the P2 porin protein of nontypeable Haemophilus influenzae
Authors: Haase E M , Yi K , Morse G D , Murphy T F
Published: January 2020

The P2 porin protein is the major outer membrane protein of nontypeable Haemophilus influenzae and is a potential target of a protective immune response. Nine monoclonal antibodies (MAbs) to P2 were developed by immunizing mice with nontypeable H. influenzae whole organisms. Each MAb reacted exclusively with the homologous strain in a whole-cell immunodot assay demonstrating exquisite strain specificity. All nine MAbs recognized abundantly expressed surface-exposed epitopes on the intact bacterium by immunofluorescence and immunoelectron microscopy. Each MAb was bactericidal to the homologous strain in an in vitro complement-mediated killing assay. Immunoblot assay of cyanogen bromide cleavage products of purified P2 indicated that MAb 5F2 recognized the 10-kDa fragment, and the other eight MAbs recognized the 32-kDa fragment. Competitive ELISAs confirmed that 5F2 recognized an epitope that is different from the other eight MAbs. To further localize epitopes, MAbs 5F2 and 6G3 were studied in protein footprinting by using reversed-phase high-performance liquid chromatography. Three potential epitope-containing peptides which were reactive in an enzyme-linked immunosorbent assay with both 5F2 and 6G3 were isolated. These peptides were identified by N-terminal amino acid sequence and localized to loops 5 and 8 of the proposed model for P2. Fusion proteins consisting of glutathione S-transferase fused with variable-length peptides from loops 5 and 8 were expressed in the pGEX-2T vector. Immunoblot assay of fusion peptides of loops 5 and 8 confirmed that 5F2 recognized an epitope within residues 338 to 354 of loop 8; 6G3 and the remaining MAbs recognized an epitope within residues 213 to 229 of loop 5. These studies indicate that nontypeable H. influenzae contains bactericidal epitopes which have been mapped to two different surface-exposed loops of the P2 molecule. These potentially protective epitopes are strain specific and abundantly expressed on the surface of the intact bacterium.
Effect of lipopolysaccharide on mouse mast cell induction by a splenic cell culture system
Authors: Hu Z Q , Asano K , Yamazaki T , Shimamura T
Published: January 2020

We have previously reported a method of mast cell induction by long-term culture of mouse spleen cells without using exogenous mast cell growth factor (Z.-Q. Hu, T. Yoshida, and T. Shimamura, J. Immunol. Methods 149:173, 1992). Supernatants recovered from the long-term cultures contain endogenous interleukin 3 and soluble stem cell factor. These were assessed by the capacity of the recovered supernatants to foster the growth of a mast cell growth factor-dependent cell line and by neutralizing antibodies. Besides the soluble factors, cell-to-cell contacts mediated by membrane stem cell factor on splenic stromal cells and c-Kit receptors on mast cells also affect mast cell induction. Different lots of fetal calf serum (FCS) were examined to determine a possible trigger for cytokine production. FCS can be divided into mast cell-inducible and noninducible sera by this process. However, not all FCS lots contain mast cell growth factor. The mast cell-inducible lots contain lipopolysaccharide (LPS) confirmed by a Limulus assay. Polymyxin B can neutralize the mast cell induction activity. Non-mast cell-inducible FCS can be converted to inducible FCS by adding exogenous LPS. The results indicate that LPS as a trigger of cytokine production is responsible for mast cell induction.
Staphylococci express a receptor for human transferrin: identification of a 42-kilodalton cell wall transferrin-binding protein
Authors: Modun B , Kendall D , Williams P
Published: January 2020

Staphylococcus aureus and the coagulase-negative staphylococci are commonly responsible for peritonitis in renal patients undergoing continuous ambulatory peritoneal dialysis. To simulate growth conditions in vivo, staphylococci isolated from peritoneal infections were cultured in used human peritoneal dialysate (HPD). Immunoblotting experiments using cell wall preparations from these staphylococci revealed the presence of the host iron-binding glycoprotein transferrin bound to S. aureus, S. epidermidis, S. capitis, S. haemolyticus, and S. hominis but not to S. warneri or S. saprophyticus. Similar results were obtained by incubating broth-grown staphylococci with human transferrin, although, in contrast to S. aureus, the coagulase-negative staphylococci bound more transferrin after growth in iron-restricted broth. To determine whether the staphylococci express a saturable specific receptor for human transferrin, the interaction of human 125I-transferrin with the staphylococci was examined. Both S. aureus and S. epidermidis bound the radiolabelled iron-saturated ligand in a time- and concentration-dependent manner. From competition binding assays, the affinity (Kd) and number of receptors were estimated for S. epidermidis (Kd, 0.27 microM; 4,200 receptors per cell) and S. aureus (Kd, 0.28 microM; 4,200 receptors per cell). S. epidermidis but not S. aureus receptor activity was partially iron regulated. Human apotransferrin and iron-saturated transferrin and rabbit and rat transferrins competed equally well for the staphylococcal receptor. Bovine and porcine transferrins and ovotransferrin as well as human and bovine lactoferrins were much less effective at competing with human transferrin. Treatment of whole staphylococci with protease abolished transferrin binding, indicating the involvement of cell surface protein. Western blots (immunoblots) of cell wall preparations probed with human transferrin revealed the presence of a 42-kDa transferrin-binding protein common to both S. aureus and S. epidermidis. On Western strip blots, the binding of human transferrin to this protein was blocked by labelled human transferrin but not by albumin, immunoglobulin G, or bovine transferrin or ovotransferrin. To assess the conservation of the 42-kDa transferrin-binding protein, cell wall proteins of S. epidermidis, S. haemolyticus, S. capitis, S. hominis, S. warneri, and S. saprophyticus were Western blotted and probed with human transferrin. Only S. warneri and S. saprophyticus lacked the 42-kDa wall protein, consistent with their inability to bind transferrin. These data show that the staphylococci express a specific receptor for human transferrin based at least in part on a common 42-kDa cell wall protein.
Bactericidal/permeability-increasing protein protects vascular endothelial cells from lipopolysaccharide-induced activation and injury
Authors: Arditi M , Zhou J , Huang S H , Luckett P M , Marra M N , Kim K S
Published: January 2020

Bactericidal/permeability-increasing protein (BPI), a human neutrophil granule protein, has been shown to bind lipopolysaccharide (LPS) and neutralize LPS-mediated cytokine production in adherent monocytes and the whole-blood system. In this study we investigated the ability of recombinant human BPI (rBPI) to inhibit LPS-induced vascular endothelial cell (EC) injury and activation. rBPI inhibited significantly both rough and smooth LPS-mediated injury for cultured bovine brain microvessel ECs, as measured by lactic dehydrogenase release, and blocked the LPS-induced interleukin-6 (IL-6) release from human umbilical vein ECs in a dose-dependent manner. BPI was able to inhibit LPS-mediated EC injury or activation whether it was added before or at the same time with LPS, but delaying the time of addition of rBPI resulted only in a partial inhibition. BPI also inhibited LPS-induced tumor necrosis factor alpha, IL-1 beta, and IL-6 release from human whole blood. This inhibition of tumor necrosis factor alpha, IL-1 beta, and IL-6 release from whole blood was maximal when BPI was premixed with LPS before addition to blood and was partial when BPI was added simultaneously with LPS, but no inhibition was observed when the addition of rBPI was delayed for 5 min. These findings suggest that rBPI is a potent inhibitor of LPS-mediated responses in ECs and whole blood and underscore the potential use of BPI in treatment or prevention of endotoxic shock. In contrast, the anti-lipid A monoclonal antibodies HA-1A and E5 were ineffective in inhibiting LPS-mediated EC injury and activation as well as LPS-induced cytokine release in whole blood.
Role of gamma interferon and tumor necrosis factor alpha during T-cell-independent and -dependent phases of Mycobacterium avium infection
Authors: Appelberg R , Castro A G , Pedrosa J , Silva R A , Orme I M , Minóprio P
Published: January 2020

To design an effective immunotherapy for Mycobacterium avium infections, the protective host response to the infection must be known. Here we analyzed the role of gamma interferon (IFN-gamma) and tumor necrosis factor alpha (TNF-alpha) in the innate and acquired responses to M. avium infections in mice. T-cell depletion studies showed that CD4+ T cells were required for control of the infection. CD(4+)-depleted mice showed enhanced bacterial proliferation and at the same time showed a reduction in the level of expression of both IFN-gamma and TNF-alpha mRNAs in spleen cells. In contrast, M. bovis BCG immunization restricted M. avium proliferation and at the same time promoted expression of the mRNAs for the two cytokines. In vivo depletion studies using specific monoclonal antibodies showed that both IFN-gamma and TNF-alpha are involved in an early protection possibly involving NK cells, and furthermore, IFN-gamma is involved in the later T-cell-protective response to infection. In vivo neutralization of IFN-gamma during M. avium infection also blocked the priming for enhanced TNF-alpha secretion triggered by endotoxin. Both cytokines were found to be involved in the resistance expressed in BCG-immunized animals and exhibited additive bacteriostatic effects in vitro on bone marrow-derived macrophages infected with different strains of M. avium. These data suggest that both cytokines act in an additive or synergistic fashion in the induction of bacteriostasis and that IFN-gamma is also involved in priming TNF-alpha secretion.
Production of Apx toxins by field strains of Actinobacillus pleuropneumoniae and Actinobacillus suis
Authors: Kamp E M , Vermeulen T M , Smits M A , Haagsma J
Published: January 2020

The three Apx toxins of Actinobacillus pleuropneumoniae have potential value for use in vaccines and diagnostic tests which will be species specific instead of serotype specific, provided that the Apx toxins are species specific and all field strains produce these toxins. We examined 114 A. pleuropneumoniae field strains and found that they secreted either ApxI, ApxII, ApxI and ApxII, or ApxII and ApxIII and secreted no other cytolytic activities. However, proteins similar to ApxI and ApxII were also produced by Actinobacillus suis.
Differences in functional activity of anticardiolipin antibodies from patients with syphilis and those with antiphospholipid syndrome
Authors: Pierangeli S S , Goldsmith G H , Krnic S , Harris E N
Published: January 2020

Anticardiolipin antibodies are produced both in patients with the antiphospholipid syndrome (APS) and in patients with syphilis, but lupus anticoagulant activity has been reported only for the former group. To understand these differences, affinity-purified immunoglobulin G anticardiolipin antibodies from APS (n = 11) and syphilis (n = 5) patients were compared. Only the antibodies from the APS group inhibited prothrombin conversion to thrombin and cross-reacted with phosphatidylserine. These findings may enable better definition of the phospholipid epitopes involved in the hemostatic abnormalities of APS.
Immunochemical Properties of Anti-Cord Factor Antibody
Authors: Kato Masahiko
Published: January 2020

Sera of man and animals infected with tubercle bacilli were tested for precipitating antibody to trehalose-6, 6′-dimycolate (cord factor) of
Mycobacterium tuberculosis
. None of the sera of mice and rabbits infected with
M. tuberculosis
H37Rv reacted with cord factor, whereas the sera of animals vaccinated with cord factor-methylated bovine serum albumin complex demonstrated a precipitin reaction with cord factor. Antibody against cord factor was not detected in the sera of cases of active, convalescent, and pneumonectomized human tuberculosis, indicating that the anti-cord factor antibody is not associated with tuberculous infection in man and animals. Precipitin activity against cord factor was localized in 19
S
macroglobulin (immunoglobulin M) fraction of the serum of rabbits vaccinated with cord factor-methylated bovine serum albumin complex. Analytical gel filtration and immunodiffusion studies indicated that the anti-cord factor precipitin dissociated from the cord factor-antibody complex is an immunoglobulin M antibody.
Passive Transfer of Johnin Hypersensitivity with Reactivity Resembling Clinical Paratuberculosis in Calves
Authors: Merkal R. S. , Witzel D. A.
Published: January 2020

Whole blood, white blood cells, plasma, and “febrile plasma” from an artificially hypersensitized bull were transfused, via catheter, into the mesenteric arteries of calves. After 1 to 3 days, the hypersensitivity of each calf was determined by the intra-arterial administration of johnin. Fever and diarrhea followed johnin administration in the calves that had been given whole blood or white blood cells, and diarrhea followed johnin administration in one calf that had been given plasma. Fever and diarrhea developed rapidly in the calves given “febrile plasma.” The results provided additional evidence that the fever and diarrhea of bovine Johne's disease are hypersensitivity phenomena which can be successfully transferred to calves and that the febrile response is cell-mediated; evidence that humoral antibody is involved is suggestive but not convincing.
Ultrastructure of
Ehrlichia canis
Authors: Hildebrandt Paul K. , Conroy James D. , McKee Adam E. , Nyindo M. B. A. , Huxsoll David L.
Published: January 2020

The ultrastructure of
Ehrlichia canis
was examined in both pulmonary mononuclear cells and in monocytes cultured from an infected dog. The cytoplasmic inclusions, or morulae, of
E. canis
consisted of a membrane-lined vacuole-containing elementary bodies which varied in size and number. The elementary bodies were bound by two trilamellar membranes. The organism shared morphological properties of both the genus
Rickettsia
and genus
Chlamydia
.
Studies on the Virulence of
Neisseria gonorrhoeae
I. Relation of Colonial Morphology and Resistance to Phagocytosis by Polymorphonuclear Leukocytes
Authors: Thongthai Chaufah , Sawyer William D.
Published: January 2020

Colonial varieties of
Neisseria gonorrhoeae
that are associated with virulence, types 1 and 2, were more resistant to phagocytosis by rabbit exudative polymorphonuclear leukocytes than colonial types of lesser virulence, types 3 and 4. Type 1 bacteria were resistant and type 4 gonococci were susceptible to phagocytosis by human polymorphonuclear leukocytes. Recent local type 1 isolates were similar in resistance to type 1 organisms of a standard laboratory strain (F62). Living and Formalin-treated, heat-killed, type 1 gonococci were equally resistant to phagocytosis. The antiphagocytic property of virulent colonial types was independent of leukotoxic action. Phagocytosis of both type 1 and type 4 gonococci by rabbit and human leukocytes was bactericidal. Rabbit leukocytes were superior to human leukocytes in killing gonococci. The results suggest that
N. gonorrhoeae
has virulence properties similar to those of extracellular bacterial pathogens, i.e., virulence is associated with antiphagocytic properties.
Galactose-Deficient Endotoxin from Urinary
Escherichia coli
Authors: Ryan John L. , Braude Abraham I. , Turck Marvin
Published: January 2020

Analysis of 111 rough strains of
Escherichia coli
from known urinary infections revealed for the first time that galactose-deficient rough mutants are not exclusively a laboratory phenomenon. They exist naturally with or without an epimerase deficiency and represent natural examples of the key role of galactose in the attachment of “O” side chains to the core of bacterial lipopolysaccharides.
Unique Teichoic Acid Isolated from the Cell Walls of a Strain of
Staphylococcus aureus
Authors: Reeder Walter J. , Ekstedt Richard D.
Published: January 2020

Teichoic acid antigen extracted from cell walls of a strain of
Staphylococcus aureus
has been shown to have the unique structure of glycerolphosphate, with
N
-acetyl-
d
-galactosamine as the immunodominant substituent.
Effects of Endotoxin on Gluconeogenesis, Glycogen Synthesis, and Liver Glycogen Synthase in Mice
Authors: McCallum R. E. , Berry L. Joe
Published: January 2020

This study was undertaken to characterize the nature of carbohydrate loss due to endotoxin poisoning in mice and to elucidate mechanisms responsible for the changes. Female ICR mice, fasted overnight, were injected intraperitoneally with a mean lethal dose of endotoxin extracted from
Salmonella typhimurium
strain SR-11. Liver glycogen levels, alanine-
U
-
14
C
and pyruvate-
2
-
14
C
incorporation into blood glucose and liver glycogen, glucose-
U
-
14
C
incorporation into liver glycogen, and liver glycogen synthase activities were measured at intervals after treatment. Liver glycogen in fasted mice given endotoxin was diminished significantly as early as 1 h after treatment. Liver glycogen synthase was significantly decreased in poisoned mice at 17 h. The use of actinomycin D showed that the induction of this enzyme due to fasting or hydrocortisone, or both, was inhibited by endotoxin. The incorporation of the
14
C-label from alanine-
U
-
14
C
, pyruvate-
2
-
14
C
, or glucose-
U
-
14
C
into blood glucose and liver glycogen was substantially impaired in endotoxemic animals at 12 h. Decreases in incorporation occurred as early as 4 h after treatment. The progressive increase in glycogen synthase activity observed in fasted controls was not seen in endotoxin-poisoned mice. The administration of a glucose or pyruvate load to endotoxin-treated mice did not restore gluconeogenesis, glycogen synthesis, or liver glycogen synthase activity to normal levels. The in vivo activation of glycogen synthase by glucose was significantly reduced in endotoxemic animals. These changes indicate reduced carbohydrate synthesis as a probable cause for rapid sugar loss during endotoxemia in mice.
Microbial Colonization of the Intestinal Epithelium in Suckling Mice
Authors: Davis C. P. , McAllister J. S. , Savage D. C.
Published: January 2020

Colonization by indigenous microorganisms of the mucosal epithelia of the large bowels of suckling mice was followed by microbial culture techniques and by light, fluorescence, and electron microscopy. Certain microbes colonize in distinctive patterns the cecal and colonic epithelia in these mice. Coliforms and enterococci colonize the large bowel 7 to 9 days after birth and reach high population levels during the second week. During that period, these facultative anaerobes can be detected by immunofluorescence techniques in microcolonies in the mucin on the epithelium. During the third week, however, after their populations decline to the low levels characteristic of adult mice, coliforms and enteroccoci can be observed only infrequently in the mucous layer. Anaerobic fusiform-shaped bacteria appear in the mucous layers along with the microcolonies of enterococci and coliforms during the second week after birth. These anaerobes increase in numbers in the mucin until they form thick layers on the mucosal epithelium by the end of the third week. They remain in the mucous layer throughout the life of the normal mouse. Anaerobic spiral-shaped microbes also colonize the mucous layer on the cecal and colonic epithelium. But these organisms can be detected by immunofluorescence in 1-week-old mice, well in advance of the time the fusiform-shaped bacteria can be found. In the second week, the latter microbes co-inhabit the mucous layer with the spiral-shaped organisms. The fusiform- and spiral-shaped microbes remain associated in the mucin on the cecal and colonic mucosal epithelia into the adult life of mice.
Thermal and pH Stability of Feline Calicivirus
Authors: Lee Kyu M. , Gillespie J. H.
Published: January 2020

Molar concentration of sodium chloride partially stabilized feline calicivirus against thermal inactivation at 50 C. One strain of feline calicivirus was relatively acid labile compared to another.
Pathogenicity of Stable L-Phase Variants of
Staphylococcus aureus
: Failure to Colonize Experimental Endocarditis in Rabbits
Authors: Linnemann Calvin C. , Watanakunakorn Chatrchai , Bakie Cheryl
Published: January 2020

Endocarditis was induced in the rabbit by the placement of a polyethylene catheter in the right heart. The catheter was filled with stable L-phase variants of
Staphylococcus aureus
to determine if the variant form would colonize the damaged endocardium and produce further tissue injury similar to that produced by the vegetative bacterial phase. No L-phase variants were recovered from cultures of blood or vegetations, although pure cultures of L-phase variants were obtained from all catheters, including one in place for 70 days. The vegetations were grossly similar in control animals with sterile media in the catheters and animals with catheters containing L-phase variants, although polymorphonuclear leukocytes and eosinophils were more frequently found in vegetations from animals inoculated with L-phase variants. Endocarditis was also induced in animals with vegetative
S. aureus
and then treated with penicillin G. Blood cultures in hypertonic media often grew vegetative
S. aureus
when there was no growth in routine media, but no L-phase variants were detected. Vegetative
S. aureus
, but not wall-defective variants, were isolated from vegetations of all treated animals.
Experimental Induction of Anergy to Coccidioidin by Antigens of
Coccidioides immitis
Authors: Ibrahim Ali Bin , Pappagianis Demosthenes
Published: January 2020

Failure to react to coccidioidin (anergy) often occurs in patients with disseminated coccidioidomycosis. One possible reason may be desensitization by excessive amounts of antigen. This was studied experimentally by injection of soluble and hyphal antigens of
Coccidioides immitis
into coccidioidin- and tuberculin-sensitive guinea pigs. Guinea pigs sensitized by injection of killed hyphal cells of
C. immitis
in complete Freund adjuvant were subsequently injected daily either with soluble coccidioidal antigen administered intraperitoneally or with hyphal antigen administered either subcutaneously or intraperitoneally. Gradual loss of cutaneous reactivity to coccidioidin occurred, but the reactivity to tuberculin remained unimpaired. The rapidity of desensitization was roughly proportional to the dose of antigen with desensitization occurring as early as 6 days after beginning injections. This anergic state was temporary, and reactivity returned several days after discontinuing injection of antigen. Injection of coccidioidal antigen led to production of coccidioidal complement-fixing antibody, but there was no consistent relationship between the antibody titer and state of cutaneous reactivity to coccidioidin. Peritoneal exudate or pulmonary alveolar cells from desensitized animals migrated freely in the presence of coccidioidin but were inhibited in the presence of tuberculin. Heat treatment did not impair the capacity of the soluble or hyphal antigen to induce anergy, thus suggesting that the antigen active in complement fixation was perhaps not involved in desensitization. Polysaccharide obtained by ethanol precipitation of dialyzed coccidioidin failed to induce anergy. Dialysis of the soluble coccidioidal antigen caused the loss of the desensitizing activity. Thus, specific desensitization could be induced by administration of large doses of coccidioidal antigen but dialyzable components appear important in this desensitization.
Thermography of Tuberculin Reactions in Cattle
Authors: Merkal R. S. , Larsen A. B. , Nelson H. A. , Pier A. C.
Published: January 2020

The allergic reactions of dermal induration and hyperthermia were compared in tuberculin-hypersensitive calves. Tuberculins prepared from
Mycobacterium avium, M. bovis
, and
M. paratuberculosis
were administered intradermally and the responses were compared. The indurations from immediate and delayed hypersensitivity reactions were readily distinguishable, but the hyperthermic responses appeared to contain elements of both immediate and delayed hypersensitivity.
Isolation and Characterization of an Avian Adenovirus-Associated Virus
Authors: Yates Vance J. , El Mishad Abla M. , McCormick Kenneth J. , Trentin John J.
Published: January 2020

An 18- to 20-nm virus particle was isolated from the Olson strain of quail bronchitis, an avian adenovirus. On density gradient separation the small virions were primarily found at densities of 1.39 and 1.42 g/cm
3
. The majority of the infectious particles were at the heavier density. The virus had a hexagonal outline and contained single-stranded deoxyribonucleic acid. It was resistant to heating at 56 C for more than an hour and was not inactivated by treatment with chloroform or low pH. Purified virus did not agglutinate erythrocytes of various avian and mammalian species. Replication of the small particles occurred either in chicken embryos or in cultures of embryo kidney cells coinfected with an adenovirus helper. Antigenically the virus was distinct from the adeno-associated viruses types 1, 2, 3, and 4. The virus is the avian equivalent of the adeno-associated viruses of primates and lower animals.
Immunological Control of Macrophage Proliferation In Vivo
Authors: North R. J. , Mackaness G. B.
Published: January 2020

The transfer of cell-mediated anti-
Listeria
immunity to normal recipient mice with spleen cells from convalescing donors results in a striking increase in the replication of macrophages in the recipients' livers. Macrophage division occurs 24 h earlier and is 2 to 3 times more intense than macrophage division in mice combating infection with the aid of normal spleen cells. The spleen cells responsible for triggering increased macrophage division and for mediating immunity are destroyed by anti-theta serum and complement, thus showing that they are thymus derived lymphocytes. Their capacity to trigger macrophage division is not realized in the absence of an adequate number of replicating
Listeria
in the recipients' tissues.
Role of Pili in the Virulence of
Neisseria gonorrhoeae
Authors: Punsalang Amado P. , Sawyer William D.
Published: January 2020

Gonococci of the colonial types that are associated with virulence, types 1 and 2, have pili that enable the bacteria both to attach in vitro to human epithelial cells and to resist phagocytosis by polymorphonuclear leukocytes. These piliated gonococci also agglutinate various mammalian and chicken erythrocytes. Gonococci of an avirulent colonial type, i.e., type 4, have no pili and neither attach to epithelial cells or erythrocytes nor resist phagocytosis. Like the type 4 bacteria, mechanically or enzymatically (trypsin) depiliated type 1 gonococci failed to attach to epithelial cells and erythrocytes and were susceptible to phagocytosis. Pili of types 1 and 2 gonococci were antigenically similar. Both type 1 gonococci and pili isolated from them induced in rabbits antibody that (i) precipitated gonococcal pili in immunodiffusion, (ii) reacted with piliated gonococci as tested by indirect immunofluorescent analysis, (iii) inhibited attachment of piliated gonococci to both human epithelial cells and erythrocytes, and (iv) opsonized piliated gonococci.
Outer Envelope of Virulent
Treponema pallidum
Authors: Johnson Russell C. , Ritzi Donna M. , Livermore Brian P.
Published: January 2020

Ultrathin sections of virulent
Treponema pallidum
(Nichols strain) were examined with the electron microscope, and the presence of an outer cell envelope was documented.
Effect of Heat-Labile Factors on the Neutralization of Vaccinia Virus by Human Sera
Authors: Takabayashi Kazuaki , McIntosh Kenneth
Published: January 2020

The effect of unheated guinea pig and human prevaccination serum on the neutralization of vaccinia virus was studied. Enhancement of neutralization was found in all sera containing antibody and was more marked (20- to 150-fold) in sera obtained in the first weeks after primary vaccination than in sera from immune adults or cord sera (4- to 25-fold). The enhancing factor was thought to be complement because it was destroyed by heating and ethylenediaminetetraacetic acid treatment. The fresh serum-enhanced neutralization test represents a highly sensitive and specific test which can be applied to measure low levels of vaccinia antibody not detectable by other means.
Local Antibody Response to Experimental Poliovirus Infection in the Central Nervous System of Rhesus Monkeys
Authors: Ogra Pearay L. , Ogra Swantarta S. , Al-Nakeeb Shaheen , Coppola Peter R.
Published: January 2020

By employing the techniques of immunofluorescence and radioimmunodiffusion using
32
P-labeled poliovirus as the antigen, the immunoglobulin response to poliovirus in serum, nasopharynx, spinal fluid, and in different segments of the central nervous system (CNS) was studied after intramuscular, oral, intranasal, and intrathalamic administration of inactivated (Salk), live attenuated (Sabin), or live virulent (Mahoney) type I poliovirus. Spinal fluid γG antibody was detected after immunization with Sabin or Mahoney virus and intramuscular administration of Salk vaccine. The response in the CNS was characterized by the appearance of γG antibody after oral or intrathalamic administration of Mahoney virus and rarely after intrathalamic inoculation of Sabin vaccine. The antibody activity in CNS was limited to the areas of poliovirus replication. Intrathalamic immunization with Mahoney virus resulted in local γG antibody production in the CNS in the absence of any detectable response in serum. Discrete foci of γG-containing cells were observed in those areas of CNS which contained poliovirus antibody. No immunoglobulin-containing cells or poliovirus antibody was seen in the CNS of monkeys immunized with intramuscularly or orally administered Sabin or Salk vaccine and in sham-immunized control monkeys. It is suggested that the CNS, when stimulated locally with a potent replicating viral antigen, may manifest a specific local antibody response, which is independent of the response in serum.
California Arbovirus (La Crosse) Infections II. Precipitin Antibody Tests for the Diagnosis of California Encephalitis
Authors: Balfour Henry H. , Majerle Rudolph J. , Edelman Charlene K.
Published: January 2020

Precipitin antibodies to California group arboviruses were studied by double agar gel immunodiffusion (ID) and counterimmunoelectrophoresis (CEP). Forty children with California encephalitis (CE), 12 patients with other forms of meningoencephalitis, and 120 residents of endemic CE areas were tested. Precipitin antibodies were detected only in the 40 patients with CE, whereas hemagglutination-inhibiting, neutralizing, and complement-fixing antibodies were also found in persons without a history of CE. Precipitin antibodies did not persist for more than a year, in contrast to the other three antibodies which may be detected for 2 or more years. Of the children with CE, 36% had precipitin antibodies in their acute sera by CEP and 44% by ID. Precipitin responses were subtype-specific, and the patients reacted most strongly with La Crosse virus. The results indicated that precipitin techniques would be useful for the early detection of CE in some patients and that the presence of precipitin antibodies in a patient with acute central nervous system infection is strongly suggestive of CE. In addition, precipitin tests can be used to distinguish the California subtype responsible for CE in a given area.
Characterization and Serotyping of Three Feline Reovirus Isolates
Authors: Csiza C. K.
Published: January 2020

Three feline virus isolates were shown to be members of the reovirus group by their growth characteristics in cell cultures, physicochemical properties, and appearance under an electron microscope. Their close serological relationship to, or identity with, human reovirus type III was revealed by hemagglutination, hemagglutination inhibition, serum neutralization, and gel diffusion tests. One feline isolate (636) was pathogenic for suckling mice.
Quantitative Evaluation of the Progress of Intracellular Infection In Vitro: Incorporation of
3
H-Thymidine into Deoxyribonucleic Acid by
Mycobacterium leprae
in Cultivated Blood Monocytes
Authors: Talwar G. P. , Krishnan A. D. , Gupta P. D.
Published: January 2020

Growth of intracellular parasites such as
Mycobacterium leprae
in macrophages derived from human peripheral blood monocytes can be assessed by selective incorporation of [
methyl
-
3
H
]thymidine into deoxyribonucleic acid of the bacterial cells. The radioactive precursor is not taken up by the host cells, and evidence has been presented for its incorporation into bacteria. The procedure is sensitive, reproducible, and highly quantitative.
Role of Peroxide in Phagocytic Killing of Pneumococci
Authors: Pitt Jane , Bernheimer Harriet P.
Published: January 2020

Two mutants of a pneumococcus type I with diminished peroxide production were selected from a population of nitrosoguanidine-treated cells. White cells of normal patients killed the mutant pneumococci as well as the otherwise isogenic wild-type strain. In patients studied with chronic granulomatous disease, however, the peroxide-poor strain was killed far less well than the wild type. These studies indicate that the removal of a peroxide-generating system in the phagocytic vacuole specifically brings forth the killing defect in chronic granulomatous disease.
Relationship of Pre-Existing Antibody to Subsequent Infection by
Mycoplasma pneumoniae
in Adults
Authors: McCormick David P. , Wenzel Richard P. , Senterfit Laurence B. , Beam Walter E.
Published: January 2020

An extensive study of the epidemiological and serological characteristics of
Mycoplasma pneumoniae
infection was carried out in a military population. There was an increase in the infection rate at Camp Lejeune during the summer months as indicated by a relative increase in isolations, seroconversions, and hospitalizations for
M. pneumoniae
pneumonia. Twenty-three percent of the trainees who later became infected had detectable, pre-existing antilipid antibody to
M. pneumoniae.
When the whole organism was used as antigen, a pre-existing complement fixation (CF) titer of 1:4 or greater correlated with resistance to
M. pneumoniae
disease as defined by the absence of a fourfold rise in CF antibody, shedding of organisms, and clinical illness. Pre-existing antilipid fraction CF antibody titers of 1:16 or greater correlated with protection against mild and severe
M. pneumoniae
disease. Antilipid CF antibody titers of 1:4 and 1:8 were related to protection against mild disease but were not associated with protection against pneumonia which required hospitalization. The severity of illness was directly related to the CF antibody response in trainees with acute respiratory disease and pneumonia due to
M. pneumoniae.
The findings provide a basis for the development of a
M. pneumoniae
vaccine.
Replication or Inactivation of Different Viruses by Human Lymphocyte Preparations
Authors: Denman A. M. , Rager-Zisman B. , Merigan T. C. , Tyrrell D. A. J.
Published: January 2020

Cultures of phytohemagglutinin-stimulated, unstimulated, and frozen and thawed mononuclear (as controls) cells from normal human donors were infected with different viruses. A variable pattern of virus infectivity was noted, and influenza and Coxsackie virus were rapidly inactivated even by stimulated lymphocytes. Direct inactivation by lymphocytes may be one form of host defense in infection by some viruses.
Combined Effects of Phytohemagglutinin and Staphylococcal Enterotoxin B on Deoxyribonucleic Acid Synthesis During Blast Transformation in Human Lymphocytes
Authors: Shambaugh George E. , Blumenschein George R.
Published: January 2020

Three mitogenic agents, phytohemagglutinin (PHA), staphylococcal enterotoxin B (SEB), and concanavalin A (Con A) were tested for their effects on deoxyribonucleic acid (DNA) synthesis in the normal human lymphocyte. When optimal concentrations of PHA and SEB were combined, tritiated thymidine incorporation in lymphocytes derived from several donors was enhanced significantly. In the presence of graded concentrations of one of these mitogens added to fixed optimal concentrations of the other, this enhancement was shown to be additive. By contrast, when PHA or SEB were combined with Con A, the resulting thymidine incorporation was slightly lower than for either mitogen alone. An inhibition of further thymidine incorporation when puromycin was added to lymphocytes incubated with PHA and SEB suggested that the additive effect of these mitogens was due to increased enzyme synthesis. To define potential differences in mechanisms of action underlying the additive effect of SEB and PHA, the relative contribution of the de novo and salvage pathways for pyrimidine biosynthesis was tested with cytidine, a specific salvage pathway inhibitor. Cytidine (10
−3
M) inhibited synthesis through the salvage pathway, but did not significantly alter induction of carbamyl phosphate synthetase II, the rate-limiting enzyme for the de novo pathway. An inhibition of DNA synthesis by millimolar cytidine concentrations in lymphocytes incubated with PHA or SEB, singly or in combination, suggested that pyrimidines for the observed enhancement of DNA synthesis were derived largely via the salvage pathway.
Interdental Localization of
Streptococcus mutans
as Related to Dental Caries Experience
Authors: Gibbons R. J. , Depaola P. F. , Spinell D. M. , Skobe Z.
Published: January 2020

The consistency of colonization of tooth surfaces by
Streptococcus mutans
was studied by sampling four approximal molar surfaces of 9- to 13-year-old children at weekly intervals. It was found that surfaces which harbored detectable levels of the organism tended to be consistently positive, whereas surfaces which were free of detectable levels of the organism also tended to remain that way. Of the total surfaces studied, 81.7% were either consistently positive or consistently negative throughout five consecutive weekly samplings. These data indicate that
S. mutans
does not uniformly colonize the surfaces of teeth. The consistent localized patterns of colonization observed suggest that
S. mutans
is not readily transmitted from one tooth surface to another within the mouth. Scanning electron microscope observations revealed that
S. mutans
colonized the teeth of monoinfected gnotobiotic rats as discrete localized colonies, whereas strains of
Actinomyces naeslundii
colonized in a more generalized manner. Efforts to sterilize tooth surfaces by application of iodine solution indicated that the populations of
S. mutans
on some surfaces could be affected for at least 11 to 13 weeks after treatment. The number of tooth surfaces colonized by detectable proportions of
S. mutans
was found to be far lower in a group of 18 children from Charlotte, N.C., with a low past caries experience than in 20 children from Danvers, Mass., with a high caries experience. The number of tooth surfaces infected with
S. mutans
therefore strongly paralleled the caries experience of these populations.
Hemodialysis Culture of
Serratia marcescens
in a Goat-Artificial Kidney-Fermentor System
Authors: Quarles John M. , Belding Ralph C. , Beaman Teofila Cabrera , Gerhardt Philipp
Published: January 2020

Hemodialysis was employed to simulate in vivo conditions for growth in mammalian blood, but without phagocytosis, by using the goat and
Serratia marcescens
as a host-parasite model. The blood stream was shunted surgically via prosthetic tubing from a carotid artery through the hollow-fiber membranes in an artificial kidney hemodialyzer and back into a jugular vein. The dialysate solution concurrently was pumped from a modular fermentor through the hemodialyzer jacket outside of the membranes and back into the fermentor. Hemodialysis between the two circuits was maintained continuously. When equilibrium was attained, bacteria inoculated into the dialysate circuit multiplied first exponentially at the maximal rate and then arithmetically at a lesser rate equally well under aerobic or anaerobic conditions. When a population of about 10
9
viable bacteria/ml was exceeded, the goat reacted acutely with signs of general toxemia, pyrexia, and leukopenia, apparently because of dialyzable toxic material produced by the culture. The maximal molecular size of the toxic material was defined relative to a rigid globular protein of 15,000 in molecular weight and 1.9 nm in hydrodynamic radius or to a flexible fibrous polyglycol of 5,500 in molecular weight and 2.6 nm in hydrodynamic radius, based on determinations of the membrane porosity threshold for dialysis.
Detection of Capsular Antigen Production in Unencapsulated Strains of
Staphylococcus aureus
Authors: Yoshida Kosaku , Nakamura Ayako , Ohtomo Toshichika , Iwami Sachiye
Published: January 2020

Of 91 compact-type strains of
Staphylococcus aureus
in regular serum soft agar (SSA), 82 converted diffuse-type growth in serum soft agar (pH adjusted to 6.0). With the addition of four different rabbit anticapsular sera (anti-type A, B, C, and D sera) in low pH (6.0) SSA, 21 strains of
S. aureus
showed compact-type colonial morphologies. Eleven, one, and one strains of
S. aureus
reacted singly with rabbit anticapsular sera types A, B, and C, respectively, and no strain reacted with rabbit anticapsular type D. Eight of the e strains reacted with both rabbit anticapsular sera types A and B. When the ability to absorb the converting activities of the antisera (changes of colonial morphologies of anticapsular sera in SSA) was quantitatively tested, 7- to 27-fold of these organisms were capable of absorbing the activities compared with the Smith diffuse organisms. These results suggest that even unencapsulated
S. aureus
strains are capable of producing capsular substance, although the capability is quantitatively different from strain to strain.
Two New Inhibitory Activities in Blood of Mice with Delayed Hypersensitivity, After Challenge with Specific Antigen
Authors: Salvin S. B. , Nishio J. , Shonnard J. T.
Published: January 2020

In addition to the activities associated with migration inhibitory factor and type II interferon, two other inhibitory activities have been found in the sera of mice infected intravenously with BCG and 3 weeks later challenged intravenously with old tuberculin. Growth of three bacteria,
Streptococcus faecalis, Staphylococcus aureus, Pseudomonas aeruginosa
, and one yeast,
Candida albicans
, was inhibited in vitro by a factor or factors in the serum. Also, hematopoiesis of mouse bone marrow cells in a soft agar medium was suppressed by the serum.
Predominant Gram-Positive Bacteria in Human Feces: Numbers, Variety, and Persistence
Authors: Gossling Jennifer , Slack John M.
Published: January 2020

The predominant gram-positive bacteria in 47 fecal specimens from 10 healthy men were studied by microscopic and cultural counts, by the characterization and tentative identification of isolates, and by the use of fluorescein isothiocyanate (FITC)-conjugated globulins prepared using some of the isolates. Gram-positive bacteria averaged 10

10.5±0.4(
sd

/g (wet weight) of feces with significant variation from host to host. Characterization of 865 isolates, all strict anaerobes and carbohydrate fermenters, showed 12 to 39 distinguishable strains from each host and indicated that some strains were present the full period of about 18 months. Sixty percent of the isolates belonged to one of five types, tentatively identified with five species—
Bifidobacterium adolescentis, Eubacterium aerofaciens, E. rectale, Peptostreptococcus productus
, and
Ruminococcus bromii.
There was distinct host idiosyncrasy in the pattern of estimated counts of these five types. Certain strains resembling
B. adolescentis, E. aerofaciens
, and
P. productus
, distinguished with FITC conjugates, were resident in their hosts for many months. In direct smears each strain constituted about 1% of the total bacteria.
Adherence of
Streptococcus mutans
to Dextran Synthesized in the Presence of Extracellular Dextransucrase
Authors: Kuramitsu Howard K.
Published: January 2020

Live or heat-killed cells of
Streptococcus mutans
specifically adhere to dextran previously synthesized on glass surfaces by the action of extracellular dextransucrase.
Chemotactic Responsiveness of Human Alveolar Macrophages: Effects of Cigarette Smoking
Authors: Warr Glenn A. , Martin R. Russell
Published: January 2020

Pulmonary alveolar macrophages from six cigarette smokers demonstrated higher random migration and greater chemotactic responsiveness to casein than did macrophages from seven nonsmokers. These observations are consistent with the concept that pulmonary macrophages are metabolically activated by cigarette smoking.
Cytotoxic Activity of
Mycobacterium ulcerans
Authors: Read John K. , Heggie Charlotte M. , Meyers Wayne M. , Connor Daniel H.
Published: January 2020

Although
Mycobacterium ulcerans
elicits extensive necrosis of human skin and subcutaneous tissue, the specific cause of the necrosis has never been elucidated. In an attempt to define a toxic substance, 18 strains of
M. ulcerans
were inoculated into mice, and the progress of each infection was observed and compared with infections of other mycobacteria, including
M. cheloni, M. marinum
, and
M. bovis
. Culture filtrates and viable organisms of each of these mycobacteria were inoculated onto tissue culture cells. Inoculation of mouse footpads with
M. ulcerans
resulted in progressive infections, leading to ulceration and eventual death. Strains of
M. cheloni, M. marinum
, and
M. bovis
did not produce progressive infections in the mice. Culture filtrates of
M. ulcerans
produced severe cytopathogenic effects on tissue cells, but washed, viable organisms of the same strains had no cytopathogenic effect. Culture filtrates and viable organisms of
M. cheloni, M. marinum
, and
M. bovis
did not produce a cytopathogenic effect on the tissue cells. Viable organisms of selected strains of
M. ulcerans
and the culture filtrates of the same strains were inoculated into guinea pig skin. The culture filtrates and the viable organisms both caused focal necrosis and focal inflammation, changes that resemble those in the naturally occurring infection in man. Preliminary purification of the culture filtrate by ultrafiltration indicates that the toxic fraction has a molecular weight of approximately 100,000, and temperature studies indicate that the toxic fraction is heat labile.