[Patient-specific joint prothesis for ankylotic temporomandibular joints]

A 49-year-old woman who suffered from severe obstructive sleep apnea (OSA) was referred to the department of Oral-, Maxillofacial Surgery department due to progressive limitation of the mouth opening and chronic pain in both temporomandibular joints. Based on clinical and radiological examinations, the patient was diagnosed with recurrent ankylosis of the temporomandibular joints. The patient was treated with 2 patient-specific implants of the temporomandibular joint combined with a Le Fort I osteotomy, and a genioplasty including a genioglossus advancement. This treatment may have advantages for the patient such as a lower recurrence rate of ankylosis, improved maximal mouth opening, pain reduction and improved aesthetic results.

Bactericidal effect and serological response of blood and secretions in bovine vibriosis

Udder infection of vaccinated heifers with Vibrio fetus var. venerealis led to an early and severe reaction consisting of local swelling, hyperthermia, and increased blood leukocyte counts. This reaction was absent or less pronounced in heifers not previously vaccinated. This was interpreted as an immediate hypersensitivity reaction elicited in the vaccinated heifers. Specific antibodies were found in udder exudate from vaccinated heifers. Immune serum and udder exudate were moderately bactericidal and had a strong immunosuppressive and opsonophagocytic effect in rabbits. Immune cervicovaginal mucus was neither bactericidal nor opsonophagocytic or immunosuppressive. This would suggest that antibodies found in cervicovaginal mucus are not protective. It appeared that the immediate hypersensitivity observed and the subsequent transfer of antibodies from serum to udder exudate would provide by analogy a possible explanation of the mechanisms of immunity to bovine vibriosis.

Rate of Clearance of Vibrio fetus var. venerealis in the Rabbit

The rate of clearance of Vibrio fetus var. venerealis was measured by using in vivo and in vitro methods. The rate of clearance from the circulating blood increased in immune rabbits and reached a plateau 4 days after immunization. Thereafter in vivo clearance did not increase further despite rising agglutinin titers. Vibriocidal activity of freshly drawn blood paralleled the rate of in vivo clearance although it was less effective at 4 days. Vibriocidal activity of immune serum was not demonstrated at the same intervals of time as the freshly drawn blood. Vibriocidal activity of immune sera plus complement was demonstrated after 1 hr of incubation at 37 C in a candle jar. An effective systemic immune response to V. fetus var. venerealis can be elicited in the rabbit. These results suggest that humoral antibodies play an important role in effecting acquired immunity against V. fetus var. venerealis.

Evaluation of phagocytosis, bactericidal activity, and production of superoxide anion, nitric oxide, and tumor necrosis factor-alpha in Kupffer cells of neonatal pigs

OBJECTIVE

To evaluate the activity of Kupffer cells (KC) of control neonatal pigs and neonatal pigs treated with endotoxin and to compare activity of KC with that of pulmonary alveolar macrophages (PAM).

SAMPLE POPULATION

Kupffer cells and PAM obtained from 24 neonatal pigs (7 to 10 days old).

PROCEDURE

Pairs (n = 7) of littermates served as treated (lipopolysaccharide [LPS]) or untreated pigs. Pigs were euthanatized 24 hours after treatment, and cells were isolated. Cells were obtained from 10 other neonatal pigs for other assays. Functional activity of cells was evaluated by use of in vitro assays to evaluate bactericidal activity, phagocytosis, and production of superoxide anion (SOA), nitric oxide (NO), and tumor necrosis factor-alpha (TNF-alpha). Each assay was repeated on cells obtained from 4 to 6 pigs.

RESULTS

Phagocytic activity was similar in KC and PAM, but bactericidal activity and production of SDA and TNF-alpha was lower in KC. Neither KC nor PAM produced NO in response to LPS stimulation. Phagocytosis, bactericidal activity, and production of SOA were enhanced for KC obtained from neonatal pigs treated with LPS. The PAM from LPS-treated neonatal pigs had similar bactericidal activity to PAM obtained from untreated pigs.

CONCLUSIONS AND CLINICAL RELEVANCE

Functional capacity of KC is affected by endotoxin. This provides additional information of the role the liver plays in immune surveillance. In addition, the response of KC in neonatal pigs exposed to endotoxin is of value for understanding gram-negative bacterial sepsis, which is a major cause of mortality in neonatal pigs.

Loss of virulence by heterophil-adapted Salmonella pullorum

We report that reduction of virulence for day-old chicks was achieved after eight-times-repeated heterophil passage of Salmonella pullorum (SP). The virulent source strain SP-V caused 64% mortality and 89% internal organ as well as 89% cecal colonization 10 days after administration of 10(7) colony-forming units (CFU) to day-old chicks. Eight-times-repeated passage of SP in heterophils resulted in attenuated strain SP-A that was nonlethal and reduced colonization of internal organs from 89% for SP-V strain to 4.3% for SP-A strain 10 days after administration of 10(7) or 10(8) CFU to day-old chicks. Cecal colonization was reduced from 89% for SP-V strain to 0 for SP-A strain 10 days after administration of 10(7) or 10(8) CFU to day-old chicks.

Chlortetracycline modulates acute phase response of ex vivo perfused pig livers, and inhibits TNF-alpha secretion by isolated Kupffer cells

Tetracyclines have been shown to have anti-inflammatory effects in addition to their antimicrobial action. We investigated the effects of in vivo administration of chlortetracycline (CTC) on ex vivo perfused pig livers. The retention and clearance of Salmonella choleraesuis, production of acute phase proteins C-reactive protein (CRP), and haptoglobin (HPG) by whole livers were studied. The in vitro modulation by CTC of TNF-alpha secretion by pig Kupffer cells (KC) was also studied. Pigs were dosed orally with CTC for three days, and given injections of Salmonella LPS 24 h before removal of the liver. Salmonella retention and clearance by livers of pigs given CTC was lower than by control livers (p < 0.01 and p < 0.05, respectively). We demonstrated an increase of CRP and HPG by livers from control pigs after a three-hour perfusion while pigs from CTC pretreated pigs varied in this response. Further, CTC decreased the secretion of TNF-alpha by cultured KC incubated in vitro with LPS. Modulation of TNF-alpha production by CTC suggests a potential for attenuating the inflammatory response. However, this possible beneficial action of CTC was accompanied by a significant decline in the antimicrobial effect of the liver.

Comparison of heterophil phagocytosis for heterophil-adapted Salmonella enteritidis (HASE) and wild-type Salmonella enteritidis (SE)

Serial passage of Salmonella enteritidis (SE) yields heterophil-adapted SE (HASE) strains that have resulted in decreased shedding of SE in feces and reduced egg contamination. Additionally, increasing the number of heterophil passages further reduced the number and frequency of fecal shedding. To evaluate SE and heterophil interaction, nine SE strains were fluorescein isothiocyanate-labeled when viable. There were six wild-types: SE TK 474, SE TK 584, SE TK 599, SE TK 600, SE TK 655, and SE TK 657; and three HASE strains: TK 499 heterophil adapted five times, TK 598 heterophil adapted six times, and TK 605 heterophil adapted 11 times. Trials were repeated seven times in duplicate with heterophils isolated from seven healthy chickens. Heterophils were incubated with the bacterial strains at 41 C for 15 min, and 10,000 heterophils were analyzed by flow cytometry. Percentage of phagocytosis and mean channel number of fluorescence were compared. Both parameters were significantly increased for all HASE-type strains compared with wild-type, nonadapted SE strains. Increased phagocytosis of HASE bacterial strains may be significant in processing and elimination of the HASE strains and may be related to the protective effect of HASE by decreased shedding of wild-type SE challenge strains.

Reduction of fecal shedding and egg contamination of Salmonella enteritidis by increasing the number of heterophil adaptations

Serial passage of Salmonella enteritidis (SE) in chicken heterophils resulted in heterophil-adapted SE (HASE). We now report that an additional five heterophil passages have further reduced the number and frequency of fecal shedding of HASE. Eleven-times HASE (11 x HASE) given to 12 laying hens for three consecutive days reduced fecal shedding of 11 x HASE to three isolations from fecal samples during the 70-day postexposure observation period. Hens were exposed to challenge SE 74 days after treatment with 11 x HASE. Three of 12 11 x HASE-treated hens were positive for challenge SE (11/396 fecal samples, or 2.8%) between days 5 and 40 postchallenge, whereas all 12 challenge control birds were positive (118/420 fecal samples, or 28.1%) for SE. None of 12 11 x HASE-treated hens was fecal positive from day 9 postchallenge, whereas 10 of 12 challenge control hens (82/372 fecal samples, or 22.0%) remained positive until day 40, the termination of the experiment. None of 525 eggs and eggshells cultured after 11 x HASE exposure was positive for Salmonella, and none of 422 eggs and eggshells cultured after challenge SE exposure was positive for Salmonella. Eggs or eggshells from challenge control hens were positive for Salmonella in 12/479 (2.5%) cases after challenge SE exposure.

Effects of heterophil adaptation on Salmonella enteritidis fecal shedding and egg contamination

Serial passage of wild-type Salmonella enteritidis (SE) in chicken heterophils resulted in decreased shedding of SE in chicken feces and reduced egg contamination. When serially heterophil-passaged strains (heterophil-adapted SE [HASE]) were given to groups of 12 or more laying hens in drinking water at a dose of 10(8) colony-forming units for 3 consecutive days, the inoculum persisted in the feces at low frequency for a few days only. Two challenge wild-type strains, given in similar manner, persisted in feces at high frequency for 25 days or longer. The persistence of challenge strains in hens previously exposed to HASE was considerably shorter and occurred less frequently than persistence and frequency in challenge control hens. HASE strains were not isolated from any of 494 eggs laid after exposure to HASE. The challenge strain was isolated from 15 of 208 eggs (7.2%) after challenge of control hens and never from 461 eggs laid after challenge of "vaccinated" hens. I concluded that HASE clones obtained by five or more cycles of heterophil phagocytosis were avirulent and immunogenic.

Cytokine release by porcine livers perfused with lipopolysaccharide or live Salmonella choleraesuis

OBJECTIVE

To develop a model to study the kinetics and relative amounts of cytokines produced by liver cells during enteric infection.

DESIGN

Salmonella enteriditis lipopolysaccharide (LPS)- or live S choleraesuis-stimulated isolated livers from clinically normal pigs and pigs with active acute phase response.

ANIMALS

7- to 14-day-old salmonellosis-free pigs, 4 to 12/group.

PROCEDURE

Livers were removed and perfused with oxygenated Krebs-Henseleit solution for 30 minutes and with S choleraesuis or LPS added for 7 minutes. Livers were then perfused with 500 ml of fresh solution in a closed loop procedure for 180 minutes. Perfusate samples were collected for tumor necrosis factor-alpha (TNF alpha) and interleukin 6 (IL-6) bioassays.

RESULTS

Tumor necrosis factor-alpha values remained constant during perfusion of normal livers and increased in those exposed to LPS. Interleukin 6 values increased in perfusate from normal livers from 30 to 150 minutes, then decreased. In livers from pigs with an active acute phase response, TNF alpha values were reduced; IL-6 appeared by 2 minutes and decreased after 25 minutes.

CONCLUSIONS

Isolated livers could be kept viable for 3 hours, and IL-6 and TNF alpha could be measured by the bioassays used.

CLINICAL RELEVANCE

Model can be used for studying and modifying the response of liver cells to infective agents.

Natural transmission of Salmonella choleraesuis in swine

This experiment was designed to study the natural transmission of Salmonella choleraesuis in swine. Forty pigs were divided into three groups. Group 1 (n = 12) was challenged with 10(8) CFU of S. choleraesuis per ml by intranasal inoculation. One day postinoculation (p.i.), group 2 (n = 24) was commingled with group 1. Group 3 (n = 4) served as uninoculated controls. Serum samples were collected weekly. Blastogenesis assays and necropsies were performed at 1, 2, 4, 6, 9, and 12 weeks p.i., and 16 tissue samples per pig were collected and cultured. Environmental (pooled feces from the pen floor) levels of S. choleraesuis were 2.61 log10 CFU/g of feces at 24 h p.i. (immediately prior to commingling). Severe clinical signs were observed in groups 1 and 2. The results indicated that at least 16% of group 2 pigs were shedding S. choleraesuis within 24 h of commingling. At 1 week p.i., 32 of 32 group 1 and 39 of 62 group 2 tissue samples were positive for S. choleraesuis. Only 3 of 12 group 2 pigs were positive at 6, 9, and 12 weeks (1 pig for each week), indicating that only a small proportion of infected swine become long-term carriers. At 12 weeks p.i., only the colon and colonic lymph node samples of one pig from group 2 were positive. Humoral, mucosal, and cellular immune responses were similar between groups 1 and 2. These data demonstrate that a few pigs shedding low levels of Salmonella organisms before slaughter can result in rapid transmission and subsequent shedding by many swine.

Acute phase response to Salmonella in a pig liver perfusion model

Livers from 7- to 14-day old pigs were maintained on a perfusion apparatus for 3 h. The perfused livers maintained physiologic and immunologic functions during perfusion. The perfused livers retained 78-94% of a non-recirculating inoculum of approximately 1-5 x 10(8) Salmonella choleraesuis (Scs), and cleared 94.9 +/- 1.7% of the retained (Scs) during the 3-h perfusion period. When the acute phase response (APR) was induced in liver donor pigs 24 h before liver perfusion, the perfused livers had diminished capability to retain, and greatly diminished capability to clear Scs. When sterile, filtered, and concentrated liver perfusate (LP) from previous, LPS-perfused livers was added to the perfusion fluid (PF) at 50 min of Scs perfusion (passive APR), Scs clearance was inhibited. When sterile, filtered LP from previously Scs perfused livers was added to the system, liver clearance was abolished, and Scs always grew in such livers during the 3 h perfusion period. The LP of livers perfused with Scs enhanced growth of Scs in an in vitro assay. These observations suggest that products of the acute phase response favor growth of Scs in vitro and in vivo.

Characterization of a Salmonella choleraesuis isolate after repeated neutrophil exposure

Salmonella choleraesuis strain 38 (glycerol-positive fermentation) was repeatedly exposed to porcine neutrophils in an attempt to mimic in vivo conditions of the host immune system. After phagocytosis, viable intracellular S choleraesuis were isolated and the process was repeated at least 5 times. A fifth-passage strain-38 neutrophil-adapted clone, 38PMNa-5X, was isolated, and was compared with the parent wild-type strain 38 for changes. Strain 38PMNa-5X had increased resistance to killing by hydrogen peroxide and phagocyte killing by porcine neutrophils, as measured by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide reduction. Strain 38PMNa-5X was less invasive than the parent strain on Vero cell monolayers, and had been cured of a 50-kb plasmid. The 50-kb plasmid was marked with bacteriophage mini-Mu (kanamycin resistant) and was reinserted into strain 38PMNa-5X. Strain 38PMNa-5X was avirulent in mice, but the isolates with reinserted plasmids had intermediate resistance to neutrophil and hydrogen peroxide killing and had restored invasiveness and mouse virulence. Differences in complement sensitivity and enzymatic activity were not observed between the strains.

In vivo isolation of Salmonella choleraesuis from porcine neutrophils

Seventy-five pigs from 4 facilities were examined for Salmonella choleraesuis by use of bacteriologic culture of feces, blood, WBC (buffy coat), mononuclear leukocytes, and neutrophils. The organism was isolated from 0 of 75 fecal samples, compared with isolation from 39 of 75 purified neutrophil preparations. Of the pigs that did not have Salmonella isolated from feces or blood, but had S choleraesuis isolated from neutrophils, 6 were further examined. These pigs from 2 groups again had culture performed at least 3 successive times to test for repeatability and to determine optimal number of neutrophils required for Salmonella isolation. These same pigs were euthanatized and necropsied. Nineteen tissue specimens from each pig were obtained for culture, but S choleraesuis was isolated only from neutrophil samples. Results indicate that neutrophils may contribute to the carrier state in pigs and should be cultured when attempting to identify S choleraesuis carrier swine.

Safety and efficacy of an attenuated strain of Salmonella choleraesuis for vaccination of swine

The purpose of this study was to determine the safety and efficacy of a live Salmonella choleraesuis immunizing strain, obtained by repeated ingestion and recovery through porcine neutrophils. The strain was tested in mice and in pigs. The vaccine was safe and effective in controlled experimental trials, using clinical, pathologic, and microbiologic criteria. Vaccinated pigs were able to maintain normal weight gains during the 4-week observation period following challenge inoculation with a high dose of a virulent strain.

A comparison of virulent and avirulent strains of Salmonella choleraesuis and their ability to invade Vero cell monolayers

The mechanisms of invasion used by virulent and avirulent Salmonella choleraesuis were compared using a Vero cell invasion assay. Mouse virulent S. choleraesuis strain 38 and avirulent strain 9 were examined for their ability to invade and survive in Vero cells. The assay was performed by S. choleraesuis infection of the Vero cell monolayer alone and in the presence of various treatments applied to the Vero cell monolayers. Intracellular S. choleraesuis colony forming units were then counted to characterize the mechanism of bacterial uptake. Invasion was not affected by colchicine, but was significantly inhibited in the presence of cytochalasins B and D, chloroquine, and dansylcadaverine. Inhibition by the above substances suggested the importance of microfilaments and of receptor recycling in receptor mediated endocytosis. Both bacterial strains had decreased invasion in the presence of mannose and after enzymic treatment with trypsin. Mannose exposure caused a significant 48% decrease in the uptake of virulent S. choleraesuis 38 and a 28% decrease in avirulent S. choleraesuis 9. Inhibition of endosome acidification did not affect the virulent strain 38 as much as it affected avirulent strain 9. Results from these experiments suggested that Vero cell invasion by S. choleraesuis was due to host uptake by receptor mediated endocytosis, and was mediated in part by mannose-sensitive adhesins. Outer membrane proteins were extracted from the virulent and avirulent strain and compared using SDS-PAGE following surface protein labeling with 125I. Virulent S. choleraesuis 38 had a unique 35 kD protein. The outer membrane proteins of both strains were then examined by radio-immunoprecipitation and western blot using guinea pig polyclonal antisera and the 35 kD protein was again found to be unique to the virulent strain 38. Antisera against the 35 kD protein significantly inhibited invasion of Vero cells by S. choleraesuis strain 38.

Porcine neutrophil function in the presence of virulent and avirulent Salmonella choleraesuis

Porcine polymorphonuclear leukocytes (PMNLs) may be activated by bacteria to begin phagocytosis followed by oxidative and non-oxidative mechanisms of killing. The purpose of this study was to identify differences between virulent and avirulent Salmonella choleraesuis (S. choleraesuis) strains, 38 and 9 respectively, in their interactions with porcine PMNLs using five different assays. (1) Staphylococcus aureus (S. aureus) ingestion was determined by exposure of porcine PMNLs to a mixture of S. choleraesuis and 125I labeled S. aureus. There was a 2.98% and 22.20% decrease in S. aureus ingestion by mouse-avirulent S. choleraesuis 9 and mouse-virulent S. choleraesuis 38 respectively. (2) Iodination of proteins was done by exposing zymosan stimulated porcine PMNLs to S. choleraesuis in the presence of 125I and measuring its incorporation into porcine PMNL proteins. This assay indicated a 73.7% and 74.7% decrease in iodination by S. choleraesuis 9 and S. choleraesuis 38, respectively. (3) Cytochrome c reduction was performed by using porcine PMNLs, zymosan, and S. choleraesuis to determine the bacterial effect on superoxide anion production. S. choleraesuis 9 and S. choleraesuis 38 inhibited superoxide anion production by 78.0% and 92.6%, respectively. (4) Lactoferrin release from porcine PMNLs was measured by an ELISA using the supernatant from the cytochrome c assay. Results indicate a 52.0% and 61.0% increase in lactoferrin release by S. choleraesuis 9 and 38 respectively. (5) The bactericidal assay was performed by counting cfus of S. choleraesuis after preliminary incubation with porcine PMNLs, followed by killing of extracellular S. choleraesuis and lysis of porcine PMNLs. Survival of S. choleraesuis 9 and E. coli (control) were 7.50% and 1.37%, respectively, in contrast to 52.62% survival of the virulent S. choleraesuis 38. These results indicate that both strains inhibited protein iodination and caused a slight increase in lactoferrin release, but the virulent S. choleraesuis 38 inhibited S. aureus ingestion, cytochrome c reduction, and survived porcine PMNL killing more effectively than the avirulent S. choleraesuis 9.

Conjunctival and intramuscular vaccination of pigs with a live avirulent strain of Salmonella cholerae-suis

An avirulent mutant strain of Salmonella cholerae-suis was cloned for resistance to streptomycin and nalidixic acid. The mutant strain 33-13 also was used because of its avirulence and immunogenicity in mice. Weaned pigs were vaccinated with live strain 33-13; 5 pigs were vaccinated by conjunctivally administered 5.5 X 10(7) organisms (low dose), 5 were conjunctivally administered 5.5 X 10(9) organisms (high dose), and 5 pigs were administered 5.5 X 10(9) organisms (high dose) IM. Transient fever and transient fecal shedding of the vaccine strain developed in pigs vaccinated IM, but not in 2 groups of pigs vaccinated conjunctivally. After intratracheal administration of virulent strain 38-9, nonvaccinated control pigs (n = 9) developed persistent high fever, anorexia, bacteremia, diarrhea, and fecal shedding of strain 38-9, whereas vaccinated pigs remained afebrile and clinically normal. Nonvaccinated and uninfected sentinel pigs (n = 8) were kept in units of 2 pigs with each group of experimental pigs, and remained healthy throughout the experiment. Thirteen vaccinated and 7 nonvaccinated control pigs were killed 42 days after vaccination, and 2 vaccinated, 2 nonvaccinated, and 8 sentinel control pigs were killed 58 days after vaccination. Ten organs were evaluated by quantitative bacteriology on necropsy of all pigs for the presence of vaccine strain 33-13, and for virulent strain 38-9. Strain 33-13 was not found. Lung and liver, lesions were found in most of the nonvaccinated control pigs, with a high frequency of recovery of large numbers of strain 38-9 from the mesenteric lymph nodes, lungs, liver, and ileum.(ABSTRACT TRUNCATED AT 250 WORDS)

Desferoxamine and iron dextran in acute Salmonella cholerae-suis infection in pigs

Serum iron (SI)-related and hematologic changes were evaluated in a herd of weaned pigs inoculated with a strain of Salmonella cholerae-suis, causing 83% mortality within 22 days after inoculation was done. Serum iron concentrations decreased to 35% of base-line values 2 days after inoculation was done, but recovered to near base line subsequently. Total SI-binding capacity (TIBC) decreased gradually for 14 days after inoculation was done. Transferrin (TF) concentrations decreased to near half the base line throughout the postinoculation observation period. The calculated SI saturation coefficient decreased to half the base line, but recovered to or above the base-line value subsequently. Combined observations of SI, TIBC, TF, and SI saturation coefficient concentrations indicated that there was higher saturation of host iron-binding proteins and recruitment of additional iron-binding systems subsequent to 2 days after inoculation was done. Day 2 after inoculation seemed to be a critical period for host iron metabolism. Injection of supplemental iron dextran simultaneously with Salmonella infection resulted in lower mortality of iron-injected pigs (P less than 0.005). A highly significant negative correlation was observed between SI concentration and rectal temperatures after pigs were inoculated with Salmonella (r = -0.54; P less than 0.0001). Hemoglobin concentrations, mean corpuscular volume, and mean corpuscular hemoglobin were not significantly affected by Salmonella infection or iron injection concurrent with Salmonella infection.(ABSTRACT TRUNCATED AT 250 WORDS)

Iron and transferrin in acute experimental Salmonella cholerae-suis infection in pigs

The effects of experimental Salmonella cholerae-suis inoculation with a virulent and an avirulent strain on serum iron (SI), total iron-binding capacity (TIBC), and transferrin (TF) were evaluated. Inoculation of virulent strain 38 was followed by significant (P less than 0.05) decreases of SI, TIBC, and TF. Exposure to avirulent strain 33 was followed by moderate decreases of SI, TIBC, and TF. When exposure to avirulent strain 33 was followed by challenge exposure with virulent strain 38, the SI, TIBC, and TF values remained at initial values or were higher. Negative correlation was observed between rectal temperature and SI and TIBC values, but was significant (P less than 0.0001) only 7 days after inoculation of the virulent strain 38.

Application of the peroxidase-antiperoxidase immunoassay to the identification of Salmonellae from pure culture and animal tissue

The peroxidase-antiperoxidase immunoassay was developed by using selected Salmonella serotypes to evaluate its potential for use in diagnostic bacteriology. S. choleraesuis var, kunzendorf, S. dublin, and S. typhimurium were the test organisms. Strong specific staining with corresponding antiserum was achieved with smears of each Salmonella serotype on microscope slides from formalinized cell suspensions, live broth cultures of clinical isolates, and tissue suspensions from the livers and spleens of experimentally infected mice. In addition, S. choleraesuis var. kunzendorf was detected in Formalin-fixed and fresh frozen tissues from experimentally infected pigs. The results of this study indicate that the peroxidase-antiperoxidase assay is well-suited for the rapid identification of Salmonella from pure cultures and that the technique can be useful in research for the detection of this pathogen in histological sections.

Effects of cyclophosphamide on the immune response of pigs to Salmonella cholerae-suis var kunzendorf

The effects of the immunosuppressive agent cyclophosphamide (CY) on the immune response of pigs given IM challenge inoculations of a moderately virulent strain of Salmonella cholerae-suis var kunzendorf were examined. Five groups of Yorkshire-cross pigs (approx 6 kg) were given Salmonella, CY, or both at various times after the 1st of a series of doses of CY was given. The drug was administered subcutaneously in 3 doses, 2 days between doses, at a rate of 20 mg/kg of body weight. Cyclophosphamide was observed to produce significant numerical decrease of circulating leukocytes, especially the polymorphonuclear neutrophils. Circulating lymphocyte numbers were reduced to 40% to 60% of base-line values. Pigs (group 4) given 3 x 10(6) S cholerae-suis IM at the time the initial CY dose was given were clinically ill during days 6 to 12; 2 of the 5 pigs died. In contrast, pigs (group 5) given 3 x 10(6) S cholerae-suis at the time of the 3rd dosing with CY did not become clinically ill until 10 days later. A significant increase in antibody titer to S cholerae-suis was delayed in this latter group beyond that of the groups of pigs (group 4) inoculated on the 1st dosing with CY and of pigs (group 6) not given CY. A significant and prolonged increase in mean rectal temperature was observed in those pigs challenge inoculated at the time of the initial CY dose. Pigs also were sensitized to Mycobacterium avium 2 weeks before CY administration. Delayed hypersensitivity reactions were depressed in pigs treated with CY at the time of testing.

Relationship between the antibody-complement susceptibility of smooth Salmonella cholerae-suis var kunzendorf strains and their virulence for mice and pigs

In the present work, we attempted to characterize 4 field strains of Salmonella cholerae-suis var kunzendorf susceptible to antibody and complement (Ab-C), and 4 strains not susceptible to Ab-C, with respect to their virulence for mice and pigs. In vivo growth of an Ab-C-susceptible, mouse-virulent strain in the spleens of mice exceeded that of 2 Ab-C-susceptible, but mouse-avirulent strains by at least 10(4) organisms. Comparison of Ab-C susceptibility with virulence for pigs seemed to indicate that parallelism existed between Ab-C susceptibility and avirulence, except for strain 38, which was Ab-C susceptible yet virulent. There was agreement between virulence for mice and pigs, except for strains 10 and 61, which were avirulent for mice but relatively virulent for pigs. The 3 strain criteria under comparison (ie, Ab-C susceptibility, virulence for mice, and virulence for pigs) suggested only partial relatedness. Vaccination of pigs with the least virulent strain was found to protect them against challenge exposure with the most virulent strain, indicating that virulence factors may not be associated with immunogenicity.

Sensitivity of smooth Salmonella cholerae-suis var kunzendorf to killing by porcine polymorphonuclear neutrophils and its relation to mouse virulence

Twenty-two selected strains of Salmonella cholerae-suis var kunzendorf were evaluated for their in vitro susceptibility to the actions of porcine peripheral blood polymorphonuclear neutrophils (PMNs) and/or antibody (Ab). Strains were divided into 2 groups based on their previously reported sensitivity or resistance to antibody-complement (Ab-C) lysis. Strains resistant to Ab-C lysis resisted killing by PMNs to a greater extent than strains susceptible to Ab-C lysis. In the absence of PMNs, dilute Ab alone enhanced the growth of the Ab-C sensitive strains over that of the Ab-C resistant strains. Each of the strains was also injected intraperitoneally into a group of 5 mice. Four strains were totally avirulent for mice and the other 18 strains had a mean time to death of 5.1 +/- 1.8 d. PMNs killed bacteria in both the virulent and avirulent groups but no significant differences were observed. Antibody alone had a stimulating effect on the virulent strains but no effect on the avirulent strains. The difference between these groups was highly significant P = .005.

Identification of bovine lymphocyte subpopulations by a combined bacterial adherence and fluorescent antibody technique

It is known that certain strains of bacteria bind selectively to subpopulations of human peripheral blood lymphocytes. We have developed a technique which used the specificity of bacterial binding concurrently with fluorescent antibody staining methods to identify 5 B-cell and 5 T-cell subpopulations of bovine lymphocytes. In addition, greater than 95% of the peripheral blood lymphocytes could be positively identified as being either T-cells or B cells. Using ethidium bromide-stained bacteria and lymphocytes in combination with fluorescent antibody staining to detect surface immunoglobulins or T-cell antigens, the method provided a simple yet highly specific technique for the enumeration of both B and T cells in 1 preparation of peripheral blood lymphocytes. The use of bacterial rosetting with fluorescent antibody staining was found to be easier and more reliable than the methods currently used to identify bovine B- and T-lymphocyte subpopulations.

Sensitivity of smooth Salmonella cholerae-suis var kunzendorf field strains to antibody complement under various conditions

Seventy-two field strains of smooth Salmonella cholerae-suis var kunzendorf were obtained from outbreaks of swine parathyroid. The field strains were examined for susceptibility to killing by antibody-complement (Ab-C) after they were exposed to Tris-EDTA, lysozyme, or saline solution. Considerable differences were found in susceptibility to killing by Ab-C in the strain population. Some strains were highly sensitive to Ab-C under all experimental conditions, whereas others became sensitive only after prior exposure to Tris-EDTA or to lysozyme. One strain was resistant to all treatments. Numerical decrease of colony-forming units by Tris-EDTA affected the population independently of decrease of the colony-forming units by Ab-C in saline solution. Evidence was obtained to indicate that Tris-EDTA may inhibit growth of S cholerae-suis in addition to the documented effect of Tris-EDTA on the release of lipopolysaccharide from the cell wall of gram-negative bacteria.

Cell-mediated and humoral immune responses of cattle to Brucella abortus, Mycobacterium bovis, and tetanus toxoid: evaluation of immunization and assay techniques

A concentration of 2.5 X 10(-5) M 2-mercaptoethanol (2-ME) added to the medium in lymphocyte blastogenesis assays increased both the uptake of [3H]thymidine in unstimulated lymphocyte cultures and the probability of detecting antigen-sensitized cattle. The use of 2-ME did not cause lymphocytes from unsensitized cattle to react positively in blastogenesis assays. A crude brucella lysate prepared from Brucella abortus strain 19 was compared with a well-characterized brucella protein allergen prepared from B melitensis and was found to be equally suitable for use in blastogenesis assays. Cell-mediated immunity was produced most effectively in 4-month-old calves by tetanus toxoid, then by Mycobacterium bovis, and least effectively by B abortus.

Cell-mediated immune response after Brucella abortus S19 vaccination

Cell-mediated immunity to Brucella abortus S19 vaccine was measured in young heifers by the microassay for stimulation of protein synthesis (SPS) with [3H]leucine and the skin test for delayed hypersensitivity. Brucella melitensis protein allergen and a crude B abortus S19-soluble antigen were compared in the SPS test. The SPS test was negative in 5 unvaccinated heifers and strongly positive in 3 twice-vaccinated steers. However, the SPS test was positive only in 13 of 30 S19-vaccinated heifers and the delayed hypersensitivity in 9 of 29 S19-vaccinated heifers. The 2 tests gave good agreement. Vaccination-induced residual antibody titers were partly correlated with the outcome of the tests used to measure cell-mediated immunity.

Bdellovibrio and the intestinal flora of vertebrates

Bdellovibrio strain MS7 force-fed to fish and frogs via an intragastric tube did not become an integral component of the intestinal microflora. Strain MS7 fed to mice in drinking water was not recovered from the intestinal tract of mice. However, in vitro, the organism multiplied in intestinal contents of frogs and mice. Bdellovibrio inoculated into rabbit ileal loops was greatly reduced in number within 24 h. It was concluded that strains MS7 could be considered nonpathogenic to animals, at least when introduced into the digestive tract, and that it is not feasible at the present time to lyse pathogenic, gram-negative bacteria in the alimentary tract with Bdellovibrio.

Antigenicity of bdellovibrios

Antigenic relationships between 12 locally isolated bdellovibrios and 3 established reference strains (109D, 6-5-S, and UKi2) were investigated. Antigenicity of the strains was examined by use of the micro-complement fixation test, the serum and complement bactericidal test, and the immunodiffusion test. Antisera were prepared against one of the local strains (MS7) and against one of the established reference strains (UKi2). The complement fixation titers suggest a close relationship among all strains. Immunodiffusion tests produced lines of identity between the homologous strain MS7 and all other strains. It is suggested on the basis of these results that bdellovibrio may possess a common antigen.

Radial immunodiffusion of chicken serum proteins. I. Standardization of optimal test procedures

Optimal conditions were determined for the quantitaion of chicken serum albumin, conalbumin, IgG and IgM by the radial immunodiffusion test. The best diluent was 0.15 M phosphate buffered saline, pH 7.2. The optimal concentration of the rabbit antiserum in the agar plate was inversely related to the molecular weight of the protein under study. The incubation time required for maximum ring formation was directly related to the molecular weight of the proteins under study. The reproducibility of the tests was evaluated using stored and fresh antiserum-agar plates.

Transfer of immunoglobulins and antibodies in the hen's egg

The presence of immunoglobulins and antibodies were investigated in the fertile hen's egg during embryogenesis. The egg yolk, egg albumin, amniotic and allantoic fluids, chick embryo serum and intestinal contents were examined for the presence of immunoglobulin and level of antibodies.

Immunoglobulin G was not detected in fresh egg albumin, but appeared in the albumin from the 4th day of embryogenesis and persisted through the 16th day. The antibody profile of egg albumin during embryogenesis attained two peaks, which were separated by a trough on the 8th day of embryogenesis. The immunoelectrophoretic pattern of albumin IgG was different from that of egg yolk IgG.

The IgG of chick embryo serum was of γ₂ mobility on the 12th day of incubation and shifted gradually to the full range of γ₁ and γ₂ mobilities on the 20th day of incubation. Egg-transmitted antibodies appeared on the 12th day of incubation and attained peak values on the 16th day of incubation.

Moderate antibody levels were detected in the amniotic and allantoic fluids from the 12th to the 18th days of incubation.