Enzyme-linked immunosorbent assay for detection of serum antibody to CAR bacillus

An enzyme-linked immunosorbent assay (ELISA) for detection of CAR bacillus antibody in rat sera was developed by Ganaway et al., in 1985 although the ELISA method was not described in detail. We investigated antigen preparation and test procedures of the ELISA using two strains of CAR bacillus which we isolated from a mouse (CB-M) and a rat (CB-R). Allantoic fluids containing 2.4 X 10(8)/ml of CB-M and 2.0 X 10(8)/ml of CB-R were washed with sterile phosphate buffered saline (PBS), resuspended in a 1/5 volume of sterile carbonate buffer (pH 9.8) and sonicated. Then 1/40 and 1/80 dilutions of CB-M and CB-R lysates in PBS, respectively, were used for antigen solutions of ELISA. Briefly, antibodies in sera are reacted with antigens coated on the surface of microtiter plates. The amount of horse radish peroxidase labeled protein-A or anti-rat IgG bound to the antigen-antibody complexes is measured on the spectro photometer at wave length of 492 nm. A total of 180 mouse and 205 rat sera were tested against both antigens. The optical density (OD) values of 140 mouse and 161 rat sera obtained from SPF mice and rats free from CAR bacillus infection were on the average 0.005 and 0.019, respectively. On the other hand, OD values of the sera collected from CB-M or CB-R infected animals ranged from 0.20 to 1.52. According to these results, the cut-off OD value for positive reaction was set at 0.1.(ABSTRACT TRUNCATED AT 250 WORDS)

Cloning of the gene for the larvicidal toxin of Bacillus sphaericus 2362: evidence for a family of related sequences

During sporulation, Bacillus sphaericus 2362 produces a parasporal crystalline protein which is toxic for the larvae of a number of mosquito species. Using the Escherichia coli cloning vector lambda gt11, in which gene products of the inserts may be fused to beta-galactosidase, we isolated 29 bacteriophages which produced peptides-reacting with antiserum to crystal protein. On the basis of restriction enzyme analyses of the recombinants and Ouchterlony immunodiffusion experiments with induced lysogens as a source of antigens, the recombinants were assigned to three groups, designated A, B, and C. Group A consisted of three clones which appeared to express all or part of the B. sphaericus toxin gene from their own promoters and one clone producing a beta-galactosidase-toxin fusion protein. The host cells of two induced recombinant lysogens of this group were toxic to larvae of Culex pipiens. A cell suspension containing 174 ng (dry weight) of the more toxic recombinant per ml killed 50% of the larvae. Both recombinants formed peptides with molecular sizes of 27, 43, and 63 kilodaltons (kDa). The antigenically related 27- and 43-kDa peptides were distinct from the 63-kDa peptide, which resembled crystals from sporulating cells of B. sphaericus in which antigenically distinct 43- and 63-kDa proteins are derived from a 125-kDa precursor. A 3.5-kilobase HindIII fragment from recombinants having toxic activity against larvae was subcloned into pGEM-3-blue. E. coli cells harboring this fragment were toxic to mosquito larvae and produced peptides of 27, 43, and 63 kDa. The distribution of the A gene among strains of B. sphaericus of different toxicities suggested that it is the sole or principal gene encoding the larvicidal crystal protein. The two recombinants of group B and the 23 of group C were all beta-galactosidase fusion proteins, suggesting that in E. coli these genes were not readily expressed from their own promoters. The distribution of these two genes in different strains of B. sphaericus suggested that they do not have a role in the toxicity of this species to mosquito larvae.

High-affinity potassium uptake system in Bacillus acidocaldarius showing immunological cross-reactivity with the Kdp system from Escherichia coli

During growth with low levels of K+, Bacillus acidocaldarius expressed a high-affinity K+ uptake system. The following observations indicate that this system strongly resembles the Kdp-ATPase of Escherichia coli: (i) its high affinity for K+ (Km of 20 microM or below); (ii) its poor transport of Rb+; (iii) the enhanced ATPase activity of membranes derived from cells grown with low levels of K+ (this activity was stimulated by K+ and inhibited by vanadate); (iv) the expression of an extra protein with a molecular weight of 70,000 in cells grown with low levels of K+; and (v) the immunological cross-reactivity of this 70,000-molecular-weight protein with antibodies against the catalytic subunit B of the E. coli Kdp system. Antibodies against the complete E. coli Kdp system, which immunoprecipitated the whole E. coli KdpABC complex, almost exclusively precipitated the 70,000-molecular-weight protein from detergent-solubilized B. acidocaldarius membranes. The possibility that the B. acidocaldarius Kdp system consists of a single, KdpB-type subunit is discussed.

An enzyme-linked immunosorbent assay for detection of anti-Bacillus piliformis serum antibody in rabbits

An enzyme-linked immunosorbent assay (ELISA) is described for the detection of rabbit serum antibody directed against the causative agent of Tyzzer's disease, Bacillus piliformis. Ninety-four percent agreement was found between the ELISA and an indirect fluorescent antibody test. The sensitivity of the ELISA was 95% and its specificity was 92% as compared to the indirect fluorescent antibody test (IFAT). The rabbit origin B. piliformis isolate used in this ELISA was found to be cross-reactive by ELISA and IFAT to B. piliformis isolates of rat, gerbil and horse origin. This suggests that a single B. piliformis isolate may be used as antigen for an ELISA utilizable for multiple species.

Examination of 20 Bacillus species by crossed immunoelectrophoresis under taxonomic aspects

In order to examine the efficiency of crossed immunoelectrophoresis (CIE) for the differentiation of species and for the determination of taxonomic relationships within the genus Bacillus, an investigation including strains of 20 species was performed. Ultrasonic extracts (USE) of sporefree-grown vegetative cells were used. With rabbit antisera against USE of type strains, the CIE was accomplished in homologous and heterologous combinations. USE's of additional strains were included into this investigation. In order to evaluate the immunoelectropherograms, the number of precipitates was counted. A mean of 103 precipitates was found in homologous reactions. With few exceptions, heterologous combinations showed less similarity in the number of antigens. Because of their high cross-reactions, the following species could not be differentiated: B. subtilis from B. amyloliquefaciens and strains of B. coagulans, furthermore, B. cereus from B. thuringiensis. The different species revealed lower numbers of precipitates with decreasing taxonomic relationships in heterologous combinations. This observation was used to classify the investigated species by a 'position-frequency analysis' (PFA). After sorting the matrix of precipitate numbers in the ascertained optimal sequence of species, a cluster analysis was carried out. The phenogram showed 6 (respectively 8) group clusters. The members of the morphologic group I (Smith et al., 1952) was found only in group cluster 2. The phenogram was partly in agreement with phenograms based on other characteristics, e.g. DNA hybridization.

Represent the batches 2 of strain NCTC 3991 and NCTC 3992 B. coagulans?

In a previous publication (M. Hartung and E. Hellmann: Examination of 20 Bacillus Species by Crossed Immunoelectrophoresis under Taxonomic Aspects, Zbl. Bakt. Hyg. A 263 (1987) 509-524) we came to the conclusion that the species B. subtilis and B. coagulans were closely related. This statement has to be revised: The antigenic relationship is low. Further investigations have shown that all three B. coagulans-strains, although originating from different sources, were overgrown by B. subtilis. The same fact may have caused errors in other publications (e.g. Parry et al.: A Colour Atlas of Bacillus Species, Wolfe Medical Publications Ltd., London, 1983.

Comparative antigenicity of spore coat proteins from Bacillus species using antibody to spore coat proteins of Bacillus megaterium

Spore coat proteins obtained by extraction with sodium dodecylsulfate/dithiothreitol from six Bacillus spores were compared by immunoblot analysis using antibodies to spore coat proteins from two strains of B. megaterium. Although the extract from spores of each strain had heterogenous proteins with various molecular weights, there were some bands which cross-reacted with specific antibodies from B. megaterium spores. Specific antibody to 48K protein from B. megaterium ATCC 12872 cross-reacted with 17K protein from B. megaterium ATCC 19213, 13K protein from B. cereus and 50K protein from B. subtilis 60015 and B. subtilis NRRL B558. Also, specific antibody to 22K protein from the same strain cross-reacted with 22K and 17K proteins from B. megaterium ATCC 19213 and 13K protein from B. cereus T. Specific antibody to 17K protein from B. megaterium ATCC 19213 reacted with 22K and 19K proteins in addition to 17K protein of own strain, and it was cross-reactive with 16K protein from B. megaterium ATCC 12872, 19K and 27K proteins from B. thiaminolyticus, 13K protein from B. cereus.

Neuropathogenesis of Tyzzer's organism in intranasally infected mice

The neuropathogenesis of Tyzzer's organism was comparatively studied in suckling and weanling mice after intranasal inoculation. In sucklings, suppurative rhinitis was produced in 24 hr postinoculation (p.i.) and organisms were detected in olfactory as well as supporting cells of the nasal mucosa. The lesions later developed to the lamina propria and propagation of organisms was seen within basal and glandular cells. On day 3 p.i., some organisms were found along with the olfactory nerve fibers and within neurons in the olfactory bulbs. Meningoencephalitis was produced with intraneuronal growth of bacteria on day 5 p.i. or later. On day 7 p.i., the brain lesions spread multifocally to the posterior parts and bacterial antigen in the nasal mucosa disappeared. In weanlings, infection was first established in the nasal mucosa and then some necrotized lesions were produced in the olfactory bulbs though much less in severity as compared to those of sucklings. Both suckling and weanling mice had necrotizing hepatitis while hemorrhagic enteritis was seen only in some sucklings.

Specific cytotoxicity of human lymphocyte subpopulations defined by bacterial adherence

It has been shown that lymphocytes can be subdivided into subpopulations based on their binding of bacteria. Monolayers of immobilized and fixed bacteria were used here to separate T cells into BA-T1T2, adherent to Escherichia coli-2 (EC-2+) and BA-T3T4, non-adherent to this strain of bacteria (Ec-2-) (our denomination). The cells were activated in mixed lymphocyte cultures (MLC) and tested for cytotoxic activity. The BA-T1T2 cells developed the same cytotoxic activity as the sham-separated T cells whereas BA-T3T4 cells did not become cytotoxic. When the T cells were separated into BA-T2 cells, adherent to Bacillus globigii (Bg+), and BA-T1T3T4, non-adherent, (Bg- cells became cytotoxic. Since BA-T1 cells, which represent 10-20% of T cells, are common to the two populations they appear to contain all T cells needed to develop the specific cytotoxicity for allogeneic cells. When the cells were first activated in MLC for 6 days and then separated by adherence to E. coli-2 or B. globigii, all cytotoxic cells were in the non-adherent fraction. We concluded that the subpopulation of T cells which are Ec-2+Bg- (less than 20%) contain all the cells required for the development of cytoxic cell function and that after activation they become Ec-2-Bg-.

Effect of bacterial competition on the opsonization, phagocytosis, and intracellular killing of microorganisms by granulocytes

The ingestion of Escherichia coli by human granulocytes in vitro was reduced in the presence of Bacteroides fragilis or Staphylococcus aureus. This reduction of ingestion proved to be mainly attributable to the absence of opsonization of E. coli, which was due to complement consumption by B. fragilis and S. aureus. The intracellular killing of E. coli was decreased in the presence of B. fragilis and S. aureus because of consumption of complement components required for extracellular stimulation of granulocytes to kill intracellular bacteria. Decreased intracellular killing of E. coli by granulocytes containing either B. fragilis or S. aureus is due to the limited killing capacity of granulocytes. These interactions between E. coli and B. fragilis or S. aureus found for phagocytosis and intracellular killing were also observed in in vivo studies: in an experimental thigh lesion infection in mice, E. coli showed stronger proliferation after coinoculation with B. fragilis or with S. aureus than after injection of E. coli alone. These in vitro and in vivo findings indicate that bacterial interactions, not only between aerobic and anaerobic bacteria but also between two species of aerobic microorganisms, compete for host defense mechanisms (i.e., opsonization, phagocytosis, and intracellular killing).

Purification by sucrose density gradient zonal centrifugation and affinity column chromatography of antigenic substances from the livers of mice infected with Tyzzer's disease

Antigenic substances from livers of mice infected with Tyzzer's disease were purified by means of sucrose density gradient zonal centrifugation and affinity column chromatography using antiserum and checking antigenicity with the complement fixation test. Fractions obtained from zonal centrifugation fell into three main groups with different molecular weights, two of which (Fr. I and Fr. II) positively reacted with antiserum in the complement fixation tests. Both fractions were further purified by affinity column chromatography. The molecular weights of the main antigenic substances derived from Fr. I and Fr. II were determined to be about 52 000 and 66 000, respectively, by means of SDS-PAGE.

Vertical transmission of Bacillus piliformis infection (Tyzzer's disease) in a guinea pig: case report

Tyzzer's disease (Bacillus piliformis infection) was diagnosed at necropsy in a hysterectomy-derived, gnotobiotically reared guinea pig. This is the first description of spontaneous vertical, presumably transplacental, transmission of B. piliformis infection. Subsequent horizontal transmission of the infection was concluded from the presence of specific anti-B. piliformis antibodies in the sera from guinea pigs originating from different litters but reared in the same isolator.

Failure of enzyme encapsulation to prevent sensitization of workers in the dry bleach industry

BDE added to dry bleach have been associated with immunologic sensitization and development of clinical allergic disease in detergent workers and occasionally in consumers. However, improved dust control and modification of the manufacturing process through encapsulation of enzyme were believed to have reduced or eliminated these problems. To determine whether or not immunologic sensitization could still develop in the detergent industry, we studied employees of a dry bleach manufacturing plant that incorporated encapsulated BDE into a consumer product. We performed air sampling for enzyme dust and total particulates, administered questionnaires, conducted physical examinations, and spirometry in 13 currently exposed, two previously exposed and nine nonexposed, employees. To assess sensitization status, RAST and ELISA were performed. Air concentrations of enzyme dust ranged from 0.002 to 1.57 micrograms/m3; all of these levels were below the TLV of 3.9 micrograms/m3. Positive BDE-specific RAST results (3.4%, 4.4%, and 8.0% binding) were obtained in three of 12 currently exposed workers. Results of personal breathing-zone air sampling indicated that these workers had high dust-exposure levels. Specificity of RAST was verified by RAST inhibition with BDE. BDE-RAST binding was not significantly elevated in the nonworkers (range: 0.6% to 1.4% binding). Positive results for specific IgG by ELISA were obtained in four of 12 currently exposed and in one of two previously exposed workers but in none of the nonexposed workers. We conclude that immunologic sensitization can develop after occupational exposure to encapsulated BDE in the dry bleach industry. We have not proved, however, that this immunologic reactivity is related to clinical sensitivity.

Binding of bacteria in lymphocyte subpopulations: role of lectin-carbohydrate interactions

Bacteria have been found to bind to lymphocyte subpopulations in a highly reproducible manner. Some of these bacteria such as B. melitensis and a strain of E. coli binds to mammalian B. cells. The binding of B. melitensis and other bacteria is due, at least in part, to lectins on lymphocytes interacting with the carbohydrates on the LPS or LTA of the bacteria. These receptors for bacteria give some indications regarding the functional potential of the cells, suggesting the possibility that the receptors identified by bacteria are used in cellular interactions with normal or malignant cells.

The effect of Bacillus natto in feed on the sheep red blood cell antibody response in chickens

Chickens fed 10(6) or 10(7) of Bacillus natto strain BN/g of diet from hatching through 15 or 30 days of age showed an increase in ability to produce hemagglutinating antibody titer as determined by intravenous injection of sheep red blood cells, whereas no increase in antibody production ability was observed in the chickens fed 10(7) of BN/g of diet from hatching through 10 days of age.

Plaque formation by Tyzzer's organism in primary monolayer culture of mouse hepatocytes

Tyzzer's disease organism propagated on primary monolayer cultures of mouse hepatocytes and produced definite plaques. In phase contrast microscopy, the organisms were motile in the plaques. Plaque formation was inhibited by antiserum. After serial plaque cloning the organisms still had virulence in mice. To establish a standard plaquing procedure, factors affecting plaque formation were studied. The critical factors in plaque formation were the culture period of host cells before inoculation, medium for suspending the organisms, and temperature and time of infection. A 24 to 36 hr-preculture of host cells and trypticase soy broth (BBL) as the suspending medium gave the best results. The optimal conditions for infection were 37 C for 90 min. The plaquing efficiency was higher when a larger volume of inoculum was applied to host cell monolayers, suggesting that the organism played an active role in the initial stage of infection.

Increase in immunoglobulin M antibodies against gut bacteria during acute hepatitis A

The marked increase in the total serum immunoglobulin M (IgM) is a characteristic feature of acute hepatitis A. To study the nature of this IgM, we assayed serial titers of IgM antibodies against various antigens during and after acute hepatitis A. The antibodies against blood group antigen remained unchanged throughout the observation period. Thus, the production or metabolism of IgM was not nonspecifically altered. The IgM antibody against hepatitis A antigen decreased and finally disappeared during convalescence as expected. However, its time course did not correlate quantitatively with the concentration of the total serum IgM. In contrast, IgM antibodies against gut bacteria Bacteroides fragilis and Streptococcus faecalis were considerably elevated in all patients at the onset of the disease, and they normalized similarly to the total IgM during convalescence. IgM antibodies against Escherichia coli were elevated only in some of the patients. The data suggest that the amount of IgM antibodies against gut bacteria contributes significantly to the increase in the total serum IgM in acute hepatitis A.