Biomedical subjects

M Tuffrey

Publications and source records attributed to M Tuffrey.

At least 19 recordsLinked to original sources

PubMed1998

Protection against ascending infection of the genital tract by Chlamydia trachomatis is associated with recruitment of major histocompatibility complex class II antigen-presenting cells into uterine tissue.

A mouse model of ascending infection following intravaginal inoculation with a strain of Chlamydia trachomatis isolated from humans has been used to identify immune mechanisms associated with protection against genital infection. BALB/c and C3H mice differed in their susceptibilities to infection and inflammatory disease. In both mouse strains, ascension of the organism and recruitment of bone marrow-derived mononuclear leukocytes were evident in uterine tissue 1 week postinfection. By 3 weeks the organism had been cleared and inflammation had been resolved in the BALB/c mice, but both persisted in the C3H animals. In athymic nude BALB/c mice both the organism and inflammation persisted, indicating the influence of the hosts' immune response on the outcome of infection. Both BALB/c and C3H mice had a Th1 response in draining lymph nodes, with predominant production of gamma interferon and tumor necrosis factor alpha, low levels of interleukin-10, and no detectable levels of interleukin-4. However, the composition of the early uterine infiltrate differed in these two mouse strains. Cell surface labeling and analysis of light scatter properties by flow cytometry identified a population of large, CD45(+) major histocompatibility complex class II mononuclear cells, which were a prominent feature of the infiltrates in BALB/c mice but were present in significantly lower numbers in C3H mice. These cells expressed the costimulatory molecules CD86 and CD40 and stimulated allogeneic T cells, suggesting that these mononuclear cells are a population of antigen-presenting cells and that they may play a role in clearing antigen and protecting against inflammatory disease in BALB/c mice. An additional level of immunological control may thus exist in genital chlamydial infection.

Animals↗

PubMed1995

A peptide of Chlamydia trachomatis shown to be a primary T-cell epitope in vitro induces cell-mediated immunity in vivo.

Chlamydiae are a major cause of infertility and preventable blindness and there is currently no effective vaccine in humans or rodents against these organisms. We have previously shown that a peptide of 12 amino acids (termed TINKP) from a conserved region of the major outer membrane protein (MOMP) of Chlamydia trachomatis (C. trachomatis) is a primary T-cell epitope in humans. Here we showed that when dendritic cells (DC) from C3H or BALB/c mice were pulsed in vitro with the peptide they stimulated proliferation of syngeneic T cells in vitro indicating that the peptide is also a primary T-cell epitope in mice. Since the skin is a rich source of DC, we immunized mice from each strain with an intradermal injection of the peptide. Humoral and cell-mediated immunity to peptide, MOMP or whole elementary bodies (EB) of C. trachomatis (F/NI1/GU) were assessed. No antibody response to TINKP was observed. However, immunized mice showed recall responses to all three chlamydial antigens. T-cell-mediated immunity in the absence of antibody was induced by a single injection of the peptide intradermally. C. trachomatis isolated from the human genital tract causes salpingitis in mice. Preliminary studies in susceptible C3H mice indicated that intradermal injection of peptide conferred some protection against the development of salpingitis. Thus, a primary T-cell epitope identified by in vitro stimulation using DC can also initiate cell-mediated immunity in vivo and this approach may be useful in the development of vaccines.

Animals↗

PubMed1994

The effect of a single oral dose of azithromycin on chlamydial infertility and oviduct ultrastructure in mice.

Azithromycin has been recommended for the treatment of human chlamydial genital tract infections because of the sustained, chlamydicidal levels of the antibiotic which can be achieved after a single dose. The effect of single dose azithromycin on the prevention or reversal of chlamydial-induced damage to the oviduct or to fertility was assessed in a mouse model of chlamydial salpingitis which closely mimics the human disease. C3H mice were treated with progesterone and then inoculated under the ovarian bursa with a human genital tract isolate of Chlamydia trachomatis, serovar F. Azithromycin at doses from 135-250 mg/kg was administered by oral intubation. Morphological damage to the oviduct lumen was assessed by scanning electron microscopy, while fertility was assessed by breeding experiments. Treatment of mice two or seven days after infection with 135 mg/kg azithromycin completely reversed chlamydial-induced ultrastructural changes and infertility. Treatment 12 or more days after infection, at doses as high as 250 mg/kg, failed to prevent infertility. The onset of fertility correlated with the loss of ciliated epithelia from the oviduct. However, the regeneration of ciliated epithelia following azithromycin treatment did not necessarily restore tubal patency. These results, if true for women also, indicate the need for rapid, effective antibiotic therapy for chlamydial salpingitis to prevent infertility and other sequelae of tubal damage.

Administration, Oral↗

PubMed1992

Heterotypic protection of mice against chlamydial salpingitis and colonization of the lower genital tract with a human serovar F isolate of Chlamydia trachomatis by prior immunization with recombinant serovar L1 major outer-membrane protein.

Intrauterine infection of mice with a human genital tract isolate of Chlamydia trachomatis (serovar F) resulted in salpingitis. In some cases, oviduct damage was sufficient to cause infertility due to lumenal blockage. Parenteral immunization with a purified, heterologous, recombinant major outer-membrane (rMOMP) preparation reduced the proportion of animals developing severe salpingitis by 77% compared with mock-immunized controls, but failed to reduce chlamydial colonization of the lower genital tract. In contrast, mice immunized with rMOMP directly into the Peyer's patches to stimulate mucosal immunity shed fewer chlamydiae from the vagina than controls, but showed little reduction in oviduct damage. No consistent correlation was observed between antibody levels to rMOMP in immunized mice and reduced lower genital tract colonization. Immunization with rMOMP via the presacral space, a route previously shown to stimulate mucosal immunity in the genital tract, produced high levels of circulating anti-rMOMP IgG but only traces of anti-rMOMP IgA in vaginal secretions. There was no difference in the severity of salpingitis in these animals compared with mock-immunized controls. Immunization with rMOMP conferred no protection against infertility resulting from direct inoculation of chlamydiae into the oviducts.

Animals↗

PubMed1992

Genetic susceptibility to chlamydial salpingitis and subsequent infertility in mice.

Groups of mice from genetically defined inbred strains were infected genitally with a pathogenic human strain of Chlamydia trachomatis and their subsequent fertility was compared. The CBA, C3H (H-2o) and C3H/He-mg (H-2k) mice were less fertile than control mice, at least up to 6 months after infection. In contrast, fertility was not impaired in BALB/c mice or in congenic BALB/K mice, which had the H-2k haplotype. Reduced fertility was paralleled by the extent of histological oviductal inflammation in mice of each strain. No salpingitis was seen 21 days after infection in the BALB strains, but lesions were apparent in CBA and C3H strains up to about 70 days after inoculation and these sometimes developed into hydrosalpinges. These results indicate that susceptibility to chlamydial salpingitis and subsequent infertility is under genetic control. This control was not simply associated with the major H-2 gene complex, as mouse strains of the same haplotype (H-2k) differed in susceptibility. The fertility of BALB/c (H-2d) and BALB/K (H-2k) strains was no different from that of controls, and congenic C3H mice of differing H-2 haplotypes (H-2k and H-2o) showed reduced fertility. Although all the infected F1 (BALB/K x C3H/He-mg) mice produced litters at the same rate as untreated controls, the litters were considerably smaller. This was due to the occurrence of unilateral pregnancies in the mice inoculated under the ovarian bursae and possibly also to early fetal death in mice inoculated directly in the uterus. These findings emphasize the importance of early diagnosis and treatment of infection of the lower genital tract of women.

Animals↗

PubMed1991

The effect of a single oral dose of azithromycin on chlamydial salpingitis in mice.

Progesterone-treated C3H mice were inoculated under the ovarian bursa with a human Chlamydia trachomatis strain, serovar E, and treated variously from one week before inoculation to two weeks afterwards with a single oral dose of azithromycin. At autopsy, all 27 control mice, not given azithromycin, had histological evidence of salpingitis. Any tubal inflammation in the 139 mice which had received greater than or equal to 60 mg azithromycin/kg was always less severe than that in control mice killed on the same day. This was true also for three of the six mice given azithromycin 25 mg/kg. Salpingitis was prevented in all 38 mice given greater than or equal to 60 mg of azithromycin on the day chlamydiae were inoculated. Inflammation was found in only 35% of mice given 60-80 mg/kg of drug from two to ten days after inoculation and was less severe than in untreated control mice. This dose given later was not as effective in preventing disease. Doses of 200-240 and 100-180 mg/kg given up to a week before inoculation reduced the proportion of mice with salpingitis to 33% and 77%, respectively, while no reduction occurred with 60-80 mg/kg, although lesions were less severe than in control mice. Chlamydiae were not detected in any part of the genital tract when greater than or equal to 60 mg/kg of azithromycin were given on the day of inoculation and were rarely detected when the drug was given a week before or up to 12 days after inoculation. Re-isolation of organisms was not always associated with histological evidence of disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1990

Inhibition of urethane leukaemia virus, a murine retrovirus, in mice by zidovudine.

The purpose of the study was to characterize in vivo an immunodepressive murine retroviral 'model' for the possible testing of drugs against HIV infection. Urethane leukaemia virus (ULV) injected into adult BALB/c mice (10(5) focus-forming units/mouse) caused a small, significant splenomegaly from 2 to at least 9 weeks after virus inoculation. Virus was also present in up to 60% nucleated splenocytes (XC 'infectious centre assay'). Effects on splenomegaly and virus in splenocytes were assayed following various regimens of zidovudine given as 0.5 mg/ml or 0.25 mg/ml in drinking water. Regimens included continuous treatment both before and after ULV, only before, and only after ULV inoculation. Zidovudine was also given for a limited period immediately after virus, or initiated after virus infection was established. Zidovudine given continuously at and following ULV infection completely prevented splenomegaly and virus expression in splenocytes. No other regimen was as effective; however, limited zidovudine treatment immediately after virus inoculation greatly reduced the effects of virus, while the same dose initiated after virus infection was established had only a small ameliorating effect. We conclude that ULV may prove to be a useful addition to other available murine systems, and this is discussed.

Analysis of Variance↗

PubMed1990

Correlation of infertility with altered tubal morphology and function in mice with salpingitis induced by a human genital-tract isolate of Chlamydia trachomatis.

Progesterone-treated C3H mice were inoculated into the uterus or ovarian bursa with a human genital tract isolate of C. trachomatis (serovar E), or with control medium alone. The mice were then observed at various times up to 260 days after inoculation. Before being killed the mice were given pituitary gonadotrophins to induce ovulation. Eggs were sought in the oviducts and ciliary activity in the fimbrial and ampullary sections of the oviducts was determined by light microscopy, before detailed examination by scanning electron microscopy. Eggs were visible in all control oviducts and both mucosal ultrastructure and ciliary activity appeared normal. By contrast, eggs were not recovered from the inoculated oviducts of mice infected intrabursally, nor was ciliary activity observed up to 28 days after inoculation. After this, ciliary activity reappeared but eggs were still not transported to the oviduct. Ultrastructural studies suggested that severe mucus congestion accompanied by tubal oedema and loss of ciliated epithelia play a major role in the aetiology of chlamydial-induced tubal damage. Infertility following chlamydial salpingitis could be associated with failure of egg transportation to the oviduct. Egg transport was still impaired even when luminal ciliary activity, ultrastructural integrity and patency had recovered. Our results suggest that chlamydial salpingitis in this mouse model closely resembles the human disease in its pathology and consequences for fertility, making the model particularly relevant for research on chlamydial vaccine development.

Animals↗

PubMed1990

Characterization of skin lesions in mice following intradermal inoculation of Haemophilus ducreyi.

Twelve strains of H. ducreyi, which included two reference strains, were each inoculated intradermally into the flanks of CBA mice. All strains produced self-limited lesions which were macroscopically and microscopically typical of those seen in chancroid. Pustular nodules, about 5mm in diameter, developed at all inoculation sites by the second day when 10(7) organisms were inoculated. Approximately half of these lesions ulcerated and all had regressed by 2 weeks. Smaller nodules developed at about half the sites from the second to the fifth day when 10(6) or 10(5) organisms were given, but these did not ulcerate. No lesions were seen when 10(3) organisms were inoculated. Organisms were recovered from the lesions up to 11 days after inoculation. Specific H. ducreyi antigen, sought by a monoclonal antibody test, was detected in lesions up to 15 days following inoculation. Heat-killed organisms of H. ducreyi also produced nodules and ulcers although these were slightly smaller than those which developed after inoculation of viable bacteria. Similar lesions to those caused by H. ducreyi were produced after intradermal inoculation of about 10(8) viable or killed Neisseria gonorrhoeae organisms. Treatment of mice with ceftriaxone had little or no effect on the subsequent development of H. ducreyi-induced lesions. These findings indicated that the lesions were not produced specifically by viable H. ducreyi organisms. Ulcers were also produced following intradermal inoculation of purified lipopolysaccharide (LPS) from H. ducreyi or N. gonorrhoeae, but not by cell-free filtrates prepared from H. ducreyi cultures indicating a possible role for LPS in the pathogenesis of ulcerative skin lesions.

Animals↗

PubMed1990

Severity of salpingitis in mice after primary and repeated inoculation with a human strain of Chlamydia trachomatis.

Groups of inbred female mice of strains CBA or C3H were infected genitally with a pathogenic human strain of Chlamydia trachomatis (N.I.1, serovar F) known to produce salpingitis and infertility in mice. Mice were inoculated under the ovarian bursa or directly into the uterine cavity with chlamydiae (test groups) or with sucrose-phosphate transport medium (control groups) before being challenged with chlamydiae by the same route 12-17 weeks later. Twenty-five pairs of test and control animals were killed from 7 to 77 days after challenge and oviductal inflammatory changes, recovery of organisms, and antibody responses were compared in the two groups. Salpingitis in the mice infected previously (tests groups) was more severe than in the controls in 56% of comparisons, the same in 24% and less severe in 20%. However, despite the increase in the severity of disease, shedding of C. trachomatis from the lower genital tract was less prolonged after rechallenge or did not occur. Salpingitis occurred in spite of the almost certain presence of pre-existing serum antibody, and accelerated and accentuated antibody response in the rechallenged mice. Furthermore, the continued existence of high titres of antibody was not associated with less severe disease. Thus, the results reveal that previous exposure to chlamydiae does not prevent salpingitis and suggest that its severity is influenced by cell-mediated immune mechanisms.

Animals↗

PubMed1989

Resistance of mice to genital infection with Neisseria gonorrhoeae.

Five strains of mice (C3H, CBA, BALB/c, TO and ICR) were inoculated intra-vaginally with Neisseria gonorrhoeae in an attempt to produce an animal model of gonorrhoea. Of a total of 68 mice inoculated, only three (4.4%) were culture-positive after 3 days. Histological examination of both the genital mucosa of inoculated animals, and the mucosa of genital tract organ cultures inoculated in vitro failed to show any evidence of gonococcal adherence or colonisation. Mice of these strains, therefore, appear resistant to gonococcal infection of the genital tract.

Animals↗

PubMed1988

Failure of Chlamydia trachomatis to pass transplacentally to fetuses of TO mice infected during pregnancy.

Mice (strain TO) were inoculated with a human strain of Chlamydia trachomatis (serovar E) either 14 days before the detection of a vaginal plug (day 1 of pregnancy), or from one to nine days thereafter. The organisms were given via the intraperitoneal route (ip) or intravenously with an additional intravaginal inoculum (iv + ivag). Mice were killed on day 18 of pregnancy and the contents of the uterus examined. Chlamydiae were isolated from at least one placental disk of about a quarter of the mice. Organisms given via the ip route established placental colonisation more effectively. Thus, placental colonisation was detected in five of 16 mice given chlamydiae by the ip route (in six of eight placentas in one mouse), whereas colonisation occurred in only a single placenta from one of nine mice infected via the iv + ivag routes. Chlamydiae were isolated from 13 (6.25%) of 208 placentas examined; the degree of colonisation was variable and the individual placentas were colonised independently. Chlamydiae were not recovered from fetal tissue, even when there was heavy placental colonisation. Nor were they isolated from maternal spleens, even though there was antibody to C. trachomatis in all maternal sera; the titres were in the range 4-2048, depending on the time of chlamydial challenge. These experiments show that C. trachomatis did not cross the placenta and that the pregnancy outcome in these mice was not affected.

Animals↗

PubMed1987

Comparison of detection procedures for Chlamydia trachomatis, including enzyme immunoassays, in a mouse model of genital infection.

Two chlamydial enzyme immunoassays, Chlamydiazyme and IDEIA, were evaluated in a mouse model of chlamydial genital-tract infection. The Chlamydiazyme assay and the IDEIA were assessed on specimens from 10 and 11 mice, respectively. The animals were infected with Chlamydia trachomatis, strain SA2f, and the results obtained by these methods on vaginal specimens taken on 4 or 5 occasions during 41-42 days were compared with those obtained in cell culture and to a less extent by the MicroTrak direct immunofluorescence test. In comparison with culture, the Chlamydiazyme assay had a sensitivity of 62% and a specificity of 92%; IDEIA had a sensitivity of 76% and a specificity of 94%. These assays sometimes did not detect chlamydiae in specimens taken immediately before specimens which proved positive by culture and the immunoassays were less sensitive if swabs were taken after those for culture. The IDEIA also failed to detect chlamydiae in the late stage of the murine infection when chlamydial elementary bodies were seen by immunofluorescence. The implications of the observations for investigations in the human field as well as for further studies in the mouse are discussed.

Animals↗

PubMed1986

Infertility in mice infected genitally with a human strain of Chlamydia trachomatis.

Progesterone-treated C3H and TO mice were inoculated genitally with a human C. trachomatis strain, serovar E, designated N.I. 1 or with 2SP control medium. Of the C3H mice serving as controls 93% had litters by the end of a 6-month period compared to 31% of mice infected with chlamydiae. This infertility could not be explained by tubal occlusion, since the oviducts appeared normal at autopsy. Some of the mice were induced to superovulate. Eggs were never recovered from the oviducts on the inoculated sides of infertile mice although they were sometimes found in the lumen of the uninoculated oviducts. In contrast, eggs were recovered routinely from both oviducts of control mice. In addition, eggs and/or their accompanying cumulus cells could be seen in the periovarial space of mice inoculated with chlamydiae, indicating a failure of the transportation of eggs to the oviduct. This could explain the high incidence of ectopic pregnancies in women after chlamydial infection. No adverse effect on fertility was seen in TO mice inoculated genitally with strain N.I.1. Of the mice given 2SP medium, 73% had litters, but 87% of the mice inoculated with chlamydiae were also fertile. There was, however, a significantly greater variation in the birth weights of mice born to infected TO mothers than those born to control mice. This difference in the susceptibility of mouse strains suggests that a genetic predisposition should also be considered for man.

Animals↗

PubMed1986

Salpingitis in mice induced by human strains of Chlamydia trachomatis.

Human strains of Chlamydia trachomatis were inoculated unilaterally into the genital tracts of female TO, CBA, CBA/nu and C3H mice via the intrauterine route or under the ovarian bursa. Inflammatory changes were not seen in the oviducts or uterus of mice given two laboratory-adapted LGV serovars (L1 and L2), although chlamydiae were recovered from the lower genital tract. However, salpingitis and endometritis occurred after each of three chlamydial strains (serovars D and E) had been inoculated. Oviduct inflammation was seen for up to 6 weeks after inoculation but reached maximum severity usually after about 2 weeks, the lumen sometimes being occluded by exudate and necrotic debris. Pathological changes were seen often in both oviducts indicating canalicular spread of the organisms through the uterus. Pre-treatment of the mice with progesterone had an enhancing effect in that the lesions developed more rapidly; such treatment, in halting the oestrous cycle, probably made a larger number of target cells available for more efficient infection. Involvement of the oviduct on the uninoculated side occurred more rapidly in T-cell impaired nude mice than in immunologically normal mice, although there was little or no effect on the severity of the oviductal changes. There was evidence that the susceptibility of different strains of mice to chlamydial salpingitis varied. Thus, inflammatory changes in C3H mice were more severe than in TO mice and the changes in C3H and CBA strains were longer lasting than those in TO mice. This suggests that a possible genetic predisposition in the human situation should not be ignored. Finally, one chlamydial strain of low passage produced more severe salpingitis in mice than another strain of similar passage. By analogy different chlamydial strains may not be of equal pathogenicity in the human situation.

Animals↗

PubMed1985

The effect of homogenising tissues either before or after storage on the isolation of Chlamydia trachomatis.

To determine whether freezing before homogenisation or the reverse procedure was the best way of achieving maximal recovery of chlamydiae from solid tissues, specimens from mice infected experimentally with Chlamydia trachomatis were used. For 10 of 12 mice, three-fold to over fifty-fold more chlamydiae were isolated from portions of spleens which were homogenised before freezing in liquid nitrogen than from those which were homogenised after being stored frozen. The value of homogenising small strips of infected genital tissue before freezing was less apparent. Nevertheless, if this was undertaken, the number of chlamydiae recovered from the tissues of four of 10 mice was three-fold to seven-fold more than if the tissues were homogenised after freezing.

Animals↗

PubMed1985

Effect on Chlamydia trachomatis infection of the murine genital tract of adoptive transfer of congenic immune cells or specific antibody.

Groups of progesterone-treated female CBA/nu mice were adoptively transferred with immune spleen cells or pooled antisera from congenic immunocompetent CBA donors that had been infected with a 'fast', human strain (SA-2f) of Chlamydia trachomatis. The spleen cells were given either intravenously (6.3 X 10(7) cells) or intraperitoneally (9.5 X 10(7) cells), and the antiserum (antibody titre 1:4096) was given intravenously. Strain SA-2f was introduced into the uterine cavity of these mice approximately 3 h after cell or antiserum transfer; antiserum was given also at intervals up to 23 days later. Untreated mice serving as controls were inoculated with chlamydiae in the same way. Subsequent recovery of chlamydiae from mice in the various groups indicated that transfer of cells or antiserum had not abrogated the chlamydial infections, despite high titres of chlamydial IgG antibody in the sera of all the recipient mice. These results confirm our earlier findings but are unlike those of some other investigators working with different mouse model systems. It seems that there are differences between systemic/respiratory immune mechanisms and those which operate locally in the uterus, which may be regarded as an immunologically privileged site.

Animals↗

PubMed1984

The distribution and effect of Chlamydia trachomatis in CBA mice inoculated genitally, intra-articularly or intravenously.

A "fast" egg-killing human strain of Chlamydia trachomatis was inoculated into normal CBA and congenic CBA/nu mice, which have an impairment of T-cell function and do not produce anti-chlamydial antibodies. The mice were inoculated by the intra-uterine, intra-articular, or intravenous routes. Some of the mice were first treated with progesterone, which allows successful chlamydial infection of the mouse genital tract when the organisms are introduced genitally. Mice were sacrificed up to 27 days after inoculation. Homogenates of joints, genital tract, spleen, liver, kidneys, eyes and lungs were prepared and tested for chlamydiae in cycloheximide-treated McCoy cell cultures. Chlamydiae were detected in the genital tracts and spleens, but not in the joints, of mice inoculated via the intra-uterine route. They were found in the joints and spleens of mice inoculated intra-articularly, and were detected also in spleens and, from the 4th to 6th day after inoculation, in joints of mice given the organisms intravenously. These results were obtained irrespective of whether or not the mice had received progesterone. The numbers of chlamydiae in the spleens and joints of the nude mice were larger and they persisted longer than in the corresponding immunocompetent animals, although this was not true for chlamydiae in the genital tract of mice inoculated via the intra-uterine route. Compartmentalisation of chlamydiae was evident although the spleen was infected consistently irrespective of the route of inoculation and, as mentioned, chlamydiae were found transiently in the joints following intravenous inoculation. This suggests that chlamydiae might also enter the human joint.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗