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Biomedical subjects

K Wicher

Publications and source records attributed to K Wicher.

At least 55 records · Page 3Linked to original sources
PubMed1987

Humoral response in Treponema pallidum-infected guinea pigs: I. Antibody specificity.

Young male inbred strain 2 guinea pigs were infected intradermally with 8 X 10(7) Treponema pallidum extracted from a rabbit orchitis, and 5 months later reinfected with 10(7) T. pallidum. Ninety percent of the animals developed symptomatic lesions after initial infection but none on challenge. Immunoblotting of sera obtained at intervals after infection or reinfection showed antibodies against T. pallidum antigen (TP), nonpathogenic treponemes--T. phagedenis biotype Reiter (TR), T. refringens strain Noguchi (TN), and T. vincentii (TV)--as well as normal rabbit serum (NRS) and normal rabbit testes extract (NRT). Antibodies reacting with TP were detected as early as 17 days (five polypeptides) and steadily rose (at 3 months 17 polypeptides were seen). Cross-reacting antibodies to TR, TN, TV, or rabbit proteins decreased within 3 to 5 months. After reinfection, the antibodies to NRS increased more sharply than the anti-treponemal antibodies. Adsorption with TR and NRS of sera obtained after infection or reinfection produced a reduction of antibodies to TP by 75-87%.

Animals↗
PubMed1987

Natural antibodies to treponemal antigens in four strains of guinea-pigs.

A total of 185 serum samples obtained from healthy male and female guinea-pigs of inbred strains 2 and 13 and outbred strains C4D and Hartley A were examined for natural antibodies to treponemal antigens by ELISA using Treponema pallidum (TP), T. phagedenis biotype Reiter (TR) and T. vincentii (TV) antigens and by the FTA test. The prevalence and titres of natural antibodies depended on the age and strain of guinea-pig and the treponemal antigen used. One- and 7-day-old guinea-pigs contained significantly (P less than 0.001) higher levels of natural antibodies than did animals 1 or 3-6 months old. The similar high levels of natural antibodies in newborn guinea-pigs and their mothers (12-30 months old) and the sharp drop observed at the age of 1 month suggested maternal transfer as the mechanism of acquisition. In young adults 3-6 months old, the age group most susceptible to TP infection, antibodies to TP and TR were at their lowest levels, but antibodies reacting to TV had already begun to rise. Natural antibodies were of the IgG1 and IgG2 but not of the IgM class. The highest levels of natural antibodies were in the C4D guinea-pigs; the lowest were in the Hartley A strain. Natural antibody activity was inhibited or adsorbed by TR antigens.

Aging↗
PubMed1986

Immune response of rabbits to intrarectal injections of particulate and soluble antigens with and without enemas.

New Zealand and New York State Flemish giant rabbits were immunized by intrarectal injections of intact sheep red blood cells (SRC) or sonicated whole sheep blood, with or without prior enemas, and were challenged intravenously with SRC. Animals receiving seven injections of 20% washed SRC, with or without prior enema, did not show detectable humoral response or produce plaque-forming cells (PFC). The systemic humoral response increased moderately after a greater dose of SRC but increased sharply after immunization with sonicated whole blood. These results suggest that particulate antigens have a restricted intestinal absorption, which can be overcome by some degree of degradation or fragmentation. The consequent sensitization to intact and sonicated SRC at the intestinal level was suggested by a secondary type of immune response (IgA and IgG), as shown by the results of PFC counts and the lack or relatively low production of hemagglutinating and hemolysin antibodies. The immune response to both soluble and disrupted particulate antigens was significantly increased by a preceding enema. These animals responded much faster and produced antibodies to a wider range of plasma proteins and SRC stromata. Our findings suggest that frequent enemas may predispose to infection and immunodeficiency in some homosexual males.

Animals↗
PubMed1986

Immune dysfunction in rabbits associated with chronic administration of enemas and rectal insemination.

NZ rabbits were treated with various combinations of enemas and intrarectal insemination (1 or 3 ml of semen a week) to investigate the effects of intestinal uptake and immunogenicity of seminal components and of an unrelated antigen, bovine serum albumin (BSA), given simultaneously. For 5 months the treatment was limited to enemas and/or semen, and total immunoglobulins and antisperm and antilymphocyte antibodies were determined. Then, without interruption of the treatments, the animals received two courses of three consecutive daily intrarectal administrations of BSA, and the humoral response was determined 7 days after each course of administration. Only 1 of 18 intrarectally inseminated animals responded with production of antisperm antibodies; none had antilymphocyte antibodies. Total immunoglobulins, however, were significantly increased in animals receiving enemas alone (p less than 0.02) or followed by insemination (p less than 0.05). The humoral response to BSA was significantly (p less than 0.01) enhanced by prior administration of enemas but was moderately reduced by simultaneous administration of semen, in a dose-related fashion.

Animals↗
PubMed1986

Antigenic contents of Treponema pallidum preparations.

In investigations of syphilis various Treponema pallidum antigens are used to study the immune responses of naturally or experimentally infected hosts. In the past these antigen preparations have rarely been examined for their antigenic contents and activity. In the present study, supernatant, sediment, and solubilised preparations of T pallidum Nichols strain (20 X 10(9) organisms/ml) and T phagedenis biotype Reiter were examined by modified counterimmunoelectrophoresis and immunoblotting for their antigenic contents. No T pallidum antigen was seen in the supernatant fraction, which contained cross reacting (Reiter) antigens and rabbit serum proteins. The remaining T pallidum preparations contained T pallidum antigens, cross reacting treponemal (Reiter) antigens, and rabbit serum proteins. These findings suggest that T pallidum preparations should be examined qualitatively and quantitatively before they are used for monitoring immune responses and interpreting data. Technology for these examinations is available.

Animals↗
PubMed1986

Extensive cross reactivity between Treponema pallidum and cultivable treponemes demonstrated by sequential immunoadsorption.

Extensive cross reactivity between Treponema pallidum and three nonpathogenic species of treponemes was demonstrated by the Western blot technique. Rabbit antiserum produced by adjuvant immunization with solubilized T. pallidum antigens reacted with 34 T. pallidum antigens and with approximately 30 antigens each of T. phagedenis biotype Reiter, T. noguchii and T. vincentii. Adsorption of the antiserum with T. phagedenis Reiter removed only about half of the cross-reacting antibodies. Sequential adsorption with all three nonpathogenic treponemes removed antibodies to all but three polypeptides of 36,000, 34,000 and 27,000 daltons.

Animals↗
PubMed1985

Antigenic evidence for host origin of exudative fluids in lesions of Treponema pallidum-infected rabbits.

Mucoid fluid accumulating within syphilitic lesions has been considered to be of Treponema pallidum origin. To test this assumption, we examined testicular exudative fluids from T. pallidum-infected rabbits for the presence of T. pallidum antigens by various sensitive immunochemical methods, including Western blot analysis. Antigenic analysis of these fluids revealed host components but not treponemal antigens. Prolonged immunization of rabbits, guinea pigs, and a goat with this material in complete Freund adjuvant elicited low titers (fluorescent-treponemal-antibody test titer, less than or equal to 10) of antitreponemal antibodies in the rabbits and guinea pigs but not in the goat. The data suggest that these mucoid fluids are of host origin. The presence of mucopolysaccharides in these fluids may be related to the infective process. The possible mechanism by which mucopolysaccharides protect T. pallidum from immune mechanisms and its potential relationship to the pathogenesis of the disease are discussed.

Animals↗
PubMed1985

Differences in susceptibility to infection with Treponema pallidum (Nichols) between five strains of guinea pig.

Groups of 10 young male guinea pigs of inbred strains 2 and 13 and outbred strains Hartley A, Hartley B, and one deficient in the fourth component of complement (C4D) were infected intradermally with 80 X 10(6) Treponema pallidum (Nichols). The course of infection and production of antitreponemal antibody were examined. Strain C4D guinea pigs were the most susceptible to infection (100%); inbred strains 2 and 13 and outbred strain Hartley B showed 80-90% symptomatic infection; and the Hartley A strain was the least susceptible to infection (10%). Strain 13 animals responded with the highest antitreponemal antibody activity, and the Hartley A strain with the lowest. The results suggest that genetic factors or complement, or both, may influence the degree of susceptibility to infection with T pallidum in guinea pigs.

Animals↗
PubMed1985

Lymphocyte transformation in inbred guinea pigs infected with Treponema pallidum nichols.

T lymphocytes were purified from peritoneal exudates from young male, inbred strain 2 guinea pigs infected with 8 X 10(7) Treponema pallidum Nichols and from control animals injected with normal rabbit testes extract. Groups of animals were sacrificed after 15, 30, 60, and 90 days of infection, and the cells were analyzed for their proliferative response to concanavalin A and phytohemagglutinin and to sonicated T. pallidum, Treponema phagedenis biotype Reiter, and normal rabbit testes extract. No significant differences were observed in the responses to mitogens. Cells from infected but not from control animals responded with significant proliferation to T. pallidum antigen, but neither infected nor control cells reacted to T. phagedenis Reiter antigen. Although cells from both infected and control animals responded to normal rabbit testes extract, this response in the infected animals was transient and much lower than the response to T. pallidum antigen.

Animals↗
PubMed1984

Laboratory experience with radiometric detection of bacteremia with three culture media.

In two long-term studies, the BACTEC radiometric system for detection of bacteremia was evaluated with three culture media each: (i) BACTEC media 6A (for aerobes) and 7B (for anaerobes) plus a thioglycolate medium and (ii) BACTEC media 6A, 7B, and 8A (hypertonic). In study 1, clinically significant isolates were identified in 1,873 (13.9%) of 13,432 blood cultures with all three media. The thioglycolate medium revealed 143 (1.1%) organisms not recovered from the 6A and 7B media. In study 2, isolates were identified in 1,135 (12.9%) of 8,759 cultures with all three media; 104 (1.2%) organisms were isolated only from the hypertonic medium. The increased yield of positive cultures in the three-medium system is likely due to the larger volume of blood cultured.

Bacteria↗
PubMed1984

Studies of rabbit testes infected with Treponema pallidum. III. Immunosuppressive activity of infiltrating mononuclear cells.

When mononuclear cells infiltrating rabbit testes infected with Treponema pallidum were cocultured with autologous or homologous peripheral blood lymphocytes spontaneous stimulation and that induced by concanavalin A were suppressed. The inhibition was not due to the cytotoxic effect of the mononuclear cells or to their interference with the active site of concanavalin A (competitive inhibition). The suppressor activity was present in both T and non-T cells but was not affected by pretreatment of the mononuclear cells with indomethacin, a prostaglandin synthetase inhibitor. The suppressor activity may be intrinsic to the mononuclear cells or acquired by the cells in the testicular environment.

Animals↗
PubMed1984

Chemotaxis in experimental syphilis.

Peritoneal exudate leukocytes from normal and Treponema pallidum-infected rabbits were examined for their chemotactic response to various chemoattractants and treponemal preparations. Leukocytes from normal and infected animals responded well to bacterial and serum-derived chemoattractants. Suspensions of washed Treponema phagedenis biotype Reiter but not T. pallidum exerted significant chemotactic activity. Cells from rabbits infected for greater than or equal to 7 days demonstrated increased locomotion, suggesting the possibility of increased random motility.

Animals↗
PubMed1983

Experimental syphilis: guinea pig model.

Outbred Hartley male guinea pigs (300-400 g) were infected intradermally with various concentrations of Treponema pallidum Nichols strain in the pubic region. The median lethal dose (ID50) was approximately 10(5). The animals produced lesions visible by darkfield microscopy, treponemal antibodies (IgG only), and histopathological changes in the lymphoid organs. Though less susceptible to T pallidum infection than the rabbit when infected with a sufficient number of organisms, the guinea pig may be a useful model in experimental syphilis.

Animals↗
PubMed1983

Studies of rabbit testes infected with Treponema pallidum. I Immunopathology.

Rabbit testes were injected with suspensions of Treponema pallidum, washed T pallidum, heat killed T pallidum, or Reiter treponemes. The testes were removed three to 24 days after injection and examined for the number of treponemes, the presence of treponemal antibodies, histopathological changes, and presence of T and B cells. In animals infected with T pallidum a substantial number (10(6)-10(7)/ml) of organisms were still present at day 24 in spite of early local production of antibodies and increasing infiltration with plasma cells, T lymphocytes, and macrophages. In animals infected with washed T pallidum a lower degree of inflammation was observed than in those infected with unmodified T pallidum, and the treponemal antibodies were detected simultaneously in samples of testicular fluid and serum. In the groups injected with heat killed T pallidum and Reiter treponemes no macroscopical or microscopical changes were detected, although in the group injected with heat killed T pallidum treponemal antibodies were detected in the testicular fluid on day 24.

Animals↗
PubMed1983

Studies of rabbit testes infected with Treponema pallidum. II Local synthesis of antibodies.

Samples of serum and testicular fluid from normal rabbits and those infected with Treponema pallidum were examined for total protein, albumin, IgG, and IgM concentrations. Total protein concentrations were similar in testicular fluid from normal and infected animals but were lower than in serum. The concentrations of individual proteins in serum did not differ substantially between infected and non-infected rabbits. In testicular fluid, however, the concentrations of all three proteins, especially IgM, were greater in infected rabbits. A significantly (p less than 0.02) raised testis-IgM index, together with a higher concentration of anti-treponemal IgM in the infected testicular fluid than in autologous serum, suggests local synthesis of IgM antibodies.

Animals↗
PubMed1982

Fluorescent antibody technic used for identification and typing of Streptococcus pneumoniae.

A fluorescent antibody technic (FAT) has been developed for identification and typing of Streptococcus pneumoniae. The technic was first compared with the Neufeld test (NT) using polyvalent antiserum and isolates identified as S. pneumoniae. Of 197 isolates, 191 (97%) were positive by both technic, and six strains (3%) were negative by both methods. Both tests were also used for determination of pneumococcal types agreed in 23 of 25 tests (92%) but the Neufeld test gave false results in 2 of 25 determinations (8%). The polyvalent antiserum was used to examine by FAT direct films obtained from various specimens and the results were compared with Gram stain and cultures. Of 198 direct films in which gram-positive cocci resembling pneumococci were found, 154 were positive by FAT and 130 were positive by culture. FAT appears to be more reliable than Gram stain or culture. During a four-year period, isolated strains of pneumococci were typed by FAT and the results compared. A slight change in the incidence of the pneumococcal types was observed. Although the Neufeld test is simpler, FAT is easier to read and is a more reliable method if identifying pneumococci, especially in body fluids where the number of microorganisms might be limited. Also, FAT is a more reliable procedure in typing strains.

Antibody Specificity↗
PubMed1982

Comparison of slide agglutination test (Phadebact) with counterimmunoelectrophoresis for detection of streptococcal group antigens.

Sera from mice infected with group B streptococci and culture supernatants of group B, A, and C streptococci were examined for the presence of group-specific antigens by the Phadebact slide agglutination (PSA) test and counterimmunoelectrophoresis (CIE). The results were correlated with the number of organisms present in the blood or in vitro cultures. The PSA test was slightly more sensitive than CIE.

Agglutination Tests↗