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1.
Calves were sensitized to tuberculin and histoplasmin. The delayed-type hypersensitivity skin response to these antigens was produced and the diameter of induration measured. Repeated skin tests prior to filtration demonstrated that the amount of induration produced by these skin tests was closely reproducible. Histoplasmin or tuberculin-coated columns were then introduced into a closed circuit extracorporeal thoracic duct circulation. A significant (P is less than 0.01) reduction or ablation of the delayed-type hypersensitivity response was obtained to the antigen used to coat the column. In contrast, no significant reduction occurred in the skin test response to the other antigen. Repeated skin tests to both antigens after the cessation of filtration showed a gradual rise toward prefiltration levels in the skin test to the filtered antigen. The results of these experiments indicate that a selective population of T lymphocytes can be removed from an in vivo system. The removal of these cells can selectively reduce a delayed-type hypersensitivity skin test response to a particular antigen. These results are consistent with the hypothesis that a type of in vivo selective immunosuppression can be produced by antigen-coated columns when they are placed in an extracorporeal thoracic duct lymph circulation system.  相似文献   

2.
Transgenic (Tg) mice whose epidermal keratinocytes constitutively overexpress either B7-1 (CD80) or B7-2 (CD86) exhibited exaggerated cutaneous delayed type hypersensitivity (DTH) to haptens compared to non-Tg mice. To determine whether enhanced DTH in these Tg mice is seen in response to cutaneous fungal infections, a primary infection with Candida albicans was established by inoculating this organism on the occluded skin of Tg and non-Tg mice. These infections resolved 7 days after removal of occlusive dressing in all three groups of mice, without evidence of exaggerated inflammation in either the Tg or non-Tg mice. Only B7-2 Tg mice developed enhanced Th1-lymphocyte-mediated immune responses to C. albicans antigens after resolving this infection: enhanced footpad swelling in response to intradermal C. albicans antigens, enhanced production of mRNA encoding Th1 lymphokines in draining lymph nodes, and increased gamma interferon secreted into culture supernatants by lymph node T lymphocytes stimulated with Candida antigens in vitro. Lastly, Western blotting of sera from mice that had resolved this fungal infection indicated that only B7-2 Tg mice recognized a wide range of Candida-associated antigens. These data suggest that these two costimulatory molecules, when expressed by keratinocytes, do not deliver identical signals to C. albicans antigen-reactive Th1 lymphocytes. The enhanced immune response in B7-2 Tg mice to a cutaneous C. albicans infection demonstrates the importance of antigen presentation and costimulation in immune reactivity to fungi. Furthermore, B7-2 Tg mice may be useful in identification of protective Candida antigens.  相似文献   

3.
Candida albicans mannoprotein (MAN) administered to mice before or during immunization with viable C. albicans downregulates MAN-specific delayed hypersensitivity. In the experiments reported here we determined the effect of MAN downregulation on protective immunity in minimally immunized mice, i.e., mice exposed to C. albicans either intradermally or intragastrically, and in maximally immunized mice, i.e., mice immunized by a combination of intradermal and intragastric exposure, in experimental systemic candidiasis. MAN suppression did not induce statistically significant alterations in the protective responses in experimental candidiasis, although 8 of 12 groups of mice treated with MAN had fewer CFU of C. albicans in their kidneys than their non-MAN-treated counterparts. The results emphasize the lack of correlation of delayed hypersensitivity with protection in candidiasis and suggest that MAN may contain epitopes involved in the protective response.  相似文献   

4.
An intradermal skin test, to demonstrate a delayed cutaneous hypersensitivity reaction in Babesia equi infection in donkeys, was developed. A skin reaction to B. equi antigen was elicited in vaccinnated, infected and carrier intact and splenectomised donkeys. The histopathological examination of the skin biopsy revealed infiltration of mononuclear cells and accumulation of oedematous fluid in the deeper layers of the dermis. A leucocyte migration inhibition test was developed and its specificity as an in vitro measure of cell-mediated immunity to B. equi antigen was established. The results of this study demonstrated a correlation between cell-mediated immunity and protection.  相似文献   

5.
We compared two techniques for detecting delayed-type hypersensitivity (DTH) skin responses in 359 patients infected with human immunodeficiency virus (HIV) (mean CD4+ lymphocyte count, 387/microL). DTH responses were assessed with use of two antigenic panels administered simultaneously: tuberculin purified protein derivative (PPD) plus three control antigens (Candida albicans, mumps antigen, and tetanus toxoid) administered by the Mantoux method and by a multiple-puncture device delivering seven antigens percutaneously (MULTITEST CMI; Institut Mérieux, Lyon, France). Eighty-three patients (23%) were anergic, 216 (60%) reacted to both panels, 55 (15%) did not react to MULTITEST CMI but did react to the antigens administered by Mantoux method, and only five (1%) reacted to MULTITEST CMI without reacting to antigens administered by the Mantoux method (P < .001, McNemar's test). Each of the three possible combinations of PPD plus two control antigens administered by the Mantoux method were also superior to MULTITEST CMI for classifying patients as nonanergic (P < .001, McNemar's test). We conclude that the application of antigens by the Mantoux method is more efficient than MULTITEST CMI for detecting DTH skin responses in HIV-infected patients.  相似文献   

6.
7.
Three antigens of Candida albicans were comparatively evaluated to their ability to elicit delayed hypersensitivity (DH) responses in the mouse footpad test, using alloxan-diabetic and normal mice which were primed with heat-killed C. albicans in complete Freund adjuvant. These antigens were: (1) a preparation of sonically disrupted heat-killed cells; (2) a preparation of soluble cytoplasmic material remaining in the supernatant of a broken-cell suspension centrifuged at 100,000 g; (3) a preparation obtained by extraction of pulverized defatted cells with dilute phenol and sodium bicarbonate in water. After separation by polyacrylamide gel electrophoresis, the major components of soluble cytoplasmic material and dilute phenol extract were identified as a 43-kD protein, and glycoproteins of 21, 27 and 38 kD, respectively. Fifty-eight CD-1 outbred mice, which had received a single intravenous injection of alloxan followed by a 28-day rest period, were randomized with normal littermates to distinct experimental groups. Seven days after sensitization, mice were injected with one of the antigens in the right rear footpad and saline in the left rear footpad and the net specific increase in footpad thickness determined 24 and 48 h later. All three antigens elicited significant responses in sensitized normal mice. The responses of sensitized diabetic mice were clearly inferior to those of sensitized normal mice when heat-killed cells and soluble cytoplasmic material were used. Dilute phenol extract elicited equivalent responses at 24 and 48 h in both primed diabetic and normal mice.  相似文献   

8.
Oral Candida carriage and blood group antigen secretor status were examined in 92 healthy, young volunteers. Candida was isolated from 61 of 92 saliva samples (66% Candida carriage). In 76% of cases this was Candida albicans. Oral Candida carriage was found to be significantly associated with non-secretion of blood group antigens (P < 0.05). However, the numbers of Candida were higher in the saliva of secretors than of non-secretors (P < 0.01). A higher percentage of Candida carriage was observed in individuals with blood group O. Thus, the finding of higher carrier frequency in the non-secretors and in blood group O subjects is confirmed.  相似文献   

9.
The RapID Yeast Plus system (Innovative Diagnostic Systems, Norcross, Ga.) is a qualitative micromethod employing conventional tests and single-substrate chromogenic tests and having a 4-h incubation period. This system was compared with the API20C (bioMerieux Vitek, Hazelwood, Mo.) system, a 24- to 72-h carbohydrate assimilation method. One hundred thirty-three clinical yeast isolates, including 57 of Candida albicans, 26 of Candida tropicalis, 23 of Candida glabrata, and 27 of other yeasts, were tested by both methods. When discrepancies occurred, isolates were further tested by the Automated Yeast Biochemical Card (bioMerieux Vitek). Germ tube production and microscopic morphology were used as needed to definitively identify yeast isolates. The RapID Yeast Plus system correctly identified 125 yeast isolates, with an overall accuracy of 94% (125 of 133). Excellent correlation was found in the recognition of the three yeasts most commonly isolated from human sources. The test was 99% (105 of 106 isolates) accurate with C. albicans, C. tropicalis, and C. glabrata. The RapID Yeast Plus system compares favorably with the API20C system and provides a simple, accurate alternative to conventional assimilation methods for the rapid identification of the most commonly encountered isolates of Candida species.  相似文献   

10.
153 patients suffering from recurrent pathologies, i.e. viral infections (keratitis, keratouveitis, genital and labial herpes) uveitis, cystitis, and candidiasis were treated with in vitro produced transfer factor (TF) specific for HSV-1/2, CMV and Candida albicans. The cell-mediated immunity of seropositive patients to HSV-1/2 and/or CMV viruses was assessed using the leucocyte migration inhibition test (LMT) and lymphocyte stimulation test (LST) in presence of the corresponding antigens, and the frequency of positive tests before, during and after TF administration was studied. The data were stratified per type of test, antigen and the recipients' pathology, and statistically evaluated. For the LMT, a total of 960 tests were carried out for each antigen dilution, 3 different antigen dilutions were used per test. 240/960 tests (25.4%) were found positive during non-treatment or treatment with unspecific TF, whereas 147/346 tests (42.5%) were found positive when the antigen corresponding to the specificity of the TF administered to the patient was used (P < 0.001). When the data were stratified following pathology, a significant increased incidence of positive tests during specific treatment was also observed (0.0001 < P < 0.05). In the LST (1174 tests), a significant increase of thymidine uptake was observed in the absence of antigen (control cultures), during treatment with both specific and unspecific TF, but also in the presence of antigen and/or autologous serum during specific TF administration (P < 0.0001). TF administration also significantly increased the soluble HLA class I antigens level in 40 patients studied to this effect.  相似文献   

11.
It is important to determine what kind of antigen is involved in atopic asthma for appropriate management as well as diagnosis. We can measure total IgE and antigen specific IgE antibodies by means of RIA and EIA in vitro. Antigen specific IgE antibodies can be detected more sensitively by skin tests consisting of intradermal, prick and scratch tests, among which the intradermal test is most sensitive. To study if the antibody thus detected is functional, there are in vivo tests such as the provocation test and eye reaction with the corresponding antigen and in vitro tests such as the histamine release assay and CAST. In Japan we tend to prefer in vitro assays, while the skin test has been recommended more than in vitro assays in the United States.  相似文献   

12.
Cutaneous exposure to ultraviolet radiation suppresses the induction of T cell mediated responses such as contact and delayed type hypersensitivity (DTH) by altering the function of immune cells in the skin and causing the release of immunoregulatory cytokines. Extracts of crude Aloe barbadensis gel prevent this photosuppression. Because the regulation of contact hypersensitivity and DTH responses differ, we investigated whether protection was afforded by a single or multiple agents in Aloe and the mechanism by which this material prevents suppression of DTH immunity. The ability of Aloe gel to prevent suppression of contact hypersensitivity responses to hapten decayed rapidly after manufacture. In contrast, agents that protected against systemic suppression of DTH responses to Candida albicans were stable over time. Oligosaccharides prepared from purified Aloe polysaccharide prevented suppression of DTH responses in vivo and reduced the amount of IL-10 observed in ultraviolet irradiated murine epidermis. To assess the effect of Aloe extracts on keratinocytes, Pam 212 cells were exposed in vitro to ultraviolet radiation and treated for 1 h with Aloe oligosaccharides. Culture supernatants were collected 24 h later and injected into mice. Supernatants from ultraviolet irradiated keratinocytes suppressed the induction of DTH responses, whereas Aloe oligosaccharide treatment reduced IL-10 and blocked the suppressive activity of the supernatants. These results indicate that Aloe contains multiple immunoprotective factors and that Aloe oligosaccharides may prevent ultraviolet induced suppression of DTH by reducing keratinocyte derived immunosuppressive cytokines.  相似文献   

13.
To determine the major antigenic component of Candida albicans against immunoglobulin E (IgE) antibodies in the sera of patients with allergies who were positive for IgE antibodies to C. albicans crude antigen in a CAP system, phosphomannoproteins (CAMP/A or CAMP/B for serotype A or B strain, respectively) and their acid-stable portions (CAMP-S/A or CAMP-S/B) were isolated from beta-mercaptoethanol (2-ME) extracts of C. albicans cells of serotypes A and B, and IgE antibodies against these components were compared with those against protein complex and enolase (CAE) fractions isolated from C. albicans cells. The dot blot test, which was used to detect IgE antibodies to the C. albicans antigens, showed that IgE antibodies to the 2-ME extract and phosphomannoprotein fractions were present in the sera of 98.0% (2-ME extract), 96.8% (CAMP/A), 93.2% (CAMP-S/A), 97.2% (CAMP/B), and 81.5% (CAMP-S/B) of the patients, whereas IgE antibodies to the protein complex and CAE fractions were found in the sera of 73.6 and 48.8% of the patients, respectively. The extent of IgE binding to the 2-ME extract and phosphomannoproteins was well correlated with the fluorescence intensities estimated with the CAP system. Furthermore, the results obtained from the inhibition experiment with the CAP system indicated that the binding of IgE antibodies to Candida antigens is strongly inhibited by the phosphomannoprotein fraction and is an indication that the serum of the patients contained IgE antibodies specific to the cell wall phosphomannoproteins of C. albicans. Finally, an initial chemical analysis indicated that the epitopes for IgE antibodies on the phosphomannoproteins is a carbohydrate portion, since the ability of CAMP/A to inhibit the binding of IgE antibodies to the homologous CAMP/A was destroyed after oxidation by sodium periodate but not after digestion with proteinase K.  相似文献   

14.
BACKGROUND: Although in some cases delayed hypersensitivity may be observed, beta-lactam antibiotics frequently induce immediate allergic IgE-mediated reactions with the specificity localized in the acyl-side chain structure. Generally, delayed immunologic reactions are related to sensitized T lymphocytes and major histocompatibility complex restricted. OBJECTIVE: To investigate the prevalence of HLA class I and II antigens in patients with delayed hypersensitivity to aminopenicillins in order to evaluate a relationship between major histocompatibility complex immune response genes and aminopenicillins hypersensitivity. METHODS: We assessed 24 patients with history of delayed hypersensitivity to aminopenicillins using (1) skin test with penicilloyl polylysine, minor determinant mixture, benzylpenicillin, amoxicillin, and ampicillin; (2) patch tests with benzylpenicillin, amoxicillin, and ampicillin; (3) RAST for penicilloyls G and V; and (4) oral challenges with amoxicillin, ampicillin, and penicillin V in 18/24 patients. All patients were typed by microlymphotoxicity standard test for HLA class I and II antigens. Statistical analysis by chi2 test 2 x 2 contingency tables, according to Svejgaard, were used for comparison between patients and random Italian population (522 subjects). RESULTS: In the patients group we found higher prevalence of HLA A2 (12/24 = 50%, RR = 6.76 P < .001, EF = 0.425), DRw52 (20/24 = 83.3%, RR = 9.28, P < .001, EF = 0.74), and lower frequency of DR4 (3/24 = 12% ns). CONCLUSIONS: These data suggest that the immune mechanisms involved in adverse reactions to aminopenicillins in vivo are related to genetic markers of immune response and confirms that the presentation of penicillin-hapten determinants to lymphocyte is major histocompatibility complex restricted.  相似文献   

15.
Although Candida albicans remains the fungal species most frequently isolated as an opportunistic oral pathogen, other yeast species are often identified in human immunodeficiency virus (HIV)-seropositive patients. Candida dubliniensis phenotypically resembles C. albicans in many respects, yet it can be identified and differentiated as a unique Candida species by its phenotypic and genetic profiles. The purpose of the present study was to prospectively test for the presence of C. dubliniensis among clinical isolates and to determine the clinical and demographic characteristics of patients harboring C. dubliniensis. Over a 90-day period, isolates from 724 patients that were presumptively identified as C. albicans were screened for C. dubliniensis by use of tests for germ tube and chlamydospore production, by detection of an inability to grow at 45 degrees C, by colony color on CHROMagar Candida medium, and by the results of a sugar assimilation test with the API 20C AUX yeast identification system. Among 699 isolates retrieved from those specimens evaluated, 5 from 25 HIV-seropositive patients and 1 isolate from a patient whose HIV status was unknown were shown to be consistent by phenotyping and by electrophoretic karyotyping with the European reference strain of C. dubliniensis. One of the C. dubliniensis isolates had dose-dependent susceptibility to fluconazole (MIC, 16 microg/ml). These results confirm the presence of this interesting species in the United States and support the need for further investigations into the prevalence and pathogenesis of C. dubliniensis.  相似文献   

16.
The sensitizing capacity of brewer's yeast (Saccharomyces cerevisiae) was studied with the skin prick test method in 449 subjects, including 226 atopic dermatitis (AD) patients, 50 patients with allergic rhinitis (AR) and/or asthma (A), and 173 nonatopic controls. A positive SPT reaction (> or = + +) was seen in 94% of patients with severe AD, in 76% with moderate AD, and in 25% with mild AD or no history of AD. Patients with AR and/or A and nonatopic controls displayed a positive reaction in only 8 and 2% of cases, respectively. There was also a parallel skin prick test reactivity with other yeasts including Pityrosporum ovale and Candida albicans, suggesting cross-reactivity. Parallel skin reactivity was observed also with molds and animal dander but not with pollen or house-dust mite. A significant correlation was also found between total serum IgE level and skin prick test (SPT) results with S. cerevisiae.  相似文献   

17.
In 30 male patients suffering from recurrent condylomata acuminata, immediate hypersensitivity parameters (total IgE, PTT and prick tests) and delayed hypersensitivity against seven recall antigens (multi test) were studied. Thirty healthy male volunteers, matched in age, were the controls. Significantly higher immediate hypersensitivity activity was shown in the patient group. Qualitative evaluation of delayed type hypersensitivity showed that controls had a positive test 16 times more often than patients. A rather homogeneous suppression of delayed type hypersensitivity was found in the patient group mainly as regards the presumably most common antigens vs. the control group. This suppression was proved to be related to disease duration. The hypothesis of a CD4+ Th-2 lymphocyte predominance in recurrent condylomata, owed to longstanding or repetitive antigenic stimulation seems to adequately explain the findings of the present study.  相似文献   

18.
The effect of BCG and levamisole on the course of established murine leishmaniasis was examined. C3H mice infected subcutaneously in the perinasal region with 10(5) L. mexicana promastigotes produced chronic non-ulcerating, non-healing lesions and demonstrated positive humoral and delayed hypersensitivity responses to leishmanial antigens. Infected animals were treated during months 3-5 of infection with either live BCG or with levamisole. Neither treatment resulted in resolution of lesions or in production of a hyperallergic form of infection; similarly, neither immune responses to leishmanial antigens nor histopathological features of lesions were significantly altered. BCG treatment resulted in accelerated growth of primary leishmanial lesions and in the appearance of metastases in some animals. Levamisole treatment of uninfected animals resulted in low levels of antibodies reacting with promastigote antigens, but not in positive delayed intradermal responses. BCG induced delayed intradermal sensitivity to PPD in both infected and control animals; significantly increased delayed reactions to leishmania, were observed in treated uninfected mice.  相似文献   

19.
BACKGROUND: Anaphylaxis to the bite of Diptera and specifically the bite of the Tabanidae family (horsefly) have been sparsely documented. The coexistent hypersensitivity to both the order Diptera and Hymenoptera has not been documented. METHODS: We present a patient who experienced anaphylaxis to both insect species. Venom skin testing and RAST revealed sensitivity to several members of the Hymenoptera order. Prick, intradermal and RAST with whole body extracts of Tabanidae species is also documented in this patient. Twenty patients who are sensitive to Hymenoptera and have been bitten by horseflies but have had no reaction to the horsefly bite were used as controls. RESULTS: An anaphylactic reaction to horsefly bite has been documented in a 56-year-old white male. This patient also demonstrated evidence of anaphylactic reaction to Hymenoptera envenomation. In controls consisting of 20 patients with Hymenoptera sensitivity, there was no clinical history of reaction to horsefly bite despite the presence of positive prick and/or positive intradermal tests and/or positive RAST to mixed Tabanidae species extract. CONCLUSIONS: Skin testing to horsefly by prick and/or intradermal testing using whole body insect extract is not useful in making a diagnosis of Tabanidae hypersensitivity. RAST using Tabanidae species as antigen is similarly useless in making a diagnosis of Tabanidae hypersensitivity. In vivo and in vitro diagnosis of horsefly hypersensitivity may be achieved when the salivary gland antigen of the horsefly becomes available.  相似文献   

20.
In vitro lymphoproliferative responses to HIV-1 recombinant antigens (gp160, p24, and Rev protein) were studied in 83 patients with asymptomatic HIV-1 infection (CDC groups II and III) and circulating CD4 lymphocyte numbers > 400/mm3. Significant response to at least one of the three antigens was detected in 52.4% of the subjects, but the responses were weak, and concordance of the response to the three antigens was rare, the frequency of individuals responding to each antigen not exceeding 22.4%. Increasing frequencies of response were observed when recall antigens (tetanus toxoid and Candida albicans glycomannoprotein) (65.5%) and anti-CD3 MoAb (76.6%) were used as stimuli. Although a significant association between lymphocyte response to p24, but not gp160, and steadiness of CD4 lymphocyte numbers before the assay was observed, no predictive value for lack of CD4 cell decrease was confirmed for either antigen, and fluctuation of the responses to HIV antigens was seen during subsequent follow up. The panel of T cell assays used could be regarded as appropriate for monitoring both HIV-specific responses and T lymphocyte function during immunotherapy with soluble HIV antigens.  相似文献   

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