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1.
目的:检测早发性牙周炎患者血清抗牙龈卟啉菌脂多糖IgG抗体的滴度和亲和力,并探讨抗体滴度水平和亲和力之间的相关性。 方法: 受试者为15名早发性牙周炎患者、16名成人牙周炎患者和14名牙周健康者。检测了血清中抗牙龈卟啉菌脂多糖IgG抗体滴度和亲和力。血清IgG抗体滴度采用酶联免疫吸附试验(ELISA)测定;其亲和力通过二乙醇胺分离,ELISA测定。 结果: 早发性牙周炎患者和成人牙周炎患者的血清中抗牙龈卟啉菌脂多糖IgG抗体水平显著高于牙周健康者(P<0.01),而在早发性牙周炎患者和成人牙周炎患者之间无显著差异(P>0.05)。早发性牙周炎患者抗体亲和力显著高于成人牙周炎患者和牙周健康组(P<0.01),而成人牙周炎患者和牙周健康组之间无显著差异(P>0.05)。 结论: 早发性牙周炎患者和成人牙周炎患者的抗体滴度水平和亲和力之间不存在相关性。IgG抗体亲和力可以作为诊断早发性牙周炎的有效参数。  相似文献   

2.
Patients with adult periodontitis (AP) exhibit elevated serum antibody levels to Porphyromonas (Bacteroides) gingivalis; however, it is not known whether these antibodies originate from plasma cells in the local disease site or from peripheral lymphoid tissues. We studied the isotype and subclass levels and origin of antibodies to P. gingivalis fimbriae, since elevated serum anti-fimbriae responses were seen when compared with sera of healthy controls. IgG anti-fibriae titres were dominant and the subclass response was IgG3 much greater than IgG1 greater than IgG2 much greater than IgG4; however, some IgA anti-fimbriae antibodies were also seen. The IgA subclass fimbriae-specific response was mainly IgA1; however, significant IgA2 anti-fimbrae antibodies were seen. We also assessed numbers of anti-fimbriae antibody producing cells from peripheral blood mononuclear cells (PMBC) and from either healthy or inflamed gingiva of AP subjects. Gingival mononuclear cells (GMC) of AP patients exhibited high numbers of immunoglobulin-producing (spot-forming) cells (SFC) including fimbriae-specific antibody secreting cells in a pattern of IgG greater than IgA greater than greater than greater than IgM. However, low numbers of SFC were seen in GMC from healthy gingiva; further, no anti-fimbriae SFC responses were noted in healthy GMC. Although no fimbriae-specific immunoglobulin-producing cells were seen in PBMC, low numbers of antigen-specific SFC were found in pokeweed mitogen-triggered PBMC from AP subjects. Treatment of AP patients for plaque and surgical removal of inflamed gingiva resulted in significant reductions in serum anti-fimbriae responses. These studies show that AP patients exhibit brisk serum IgG and IgA subclass anti-fimbriae antibodies, whose origin appear to be the plasma cells present in the localized inflamed tissues.  相似文献   

3.
The level of serum IgM, IgG and IgA antibodies including IgG1, IgG2, IgG3, IgG4, IgA1 and IgA2 subclass-specific antibodies to Bacteroides (Porphyromonas) gingivalis fimbriae and to lipopolysaccharide (LPS) were analysed in patients with different forms of periodontal disease (PD) and control subjects by ELISA. Among PD subjects, sera obtained from adult periodontitis (AP), rapidly progressive periodontitis (RPP) and gingivitis contained high titres of fimbriae-specific IgG antibodies (7500-15,000 ELISA units) followed by IgA (90-700 units) and IgM (30-90 units). In contrast, sera from localized juvenile periodontitis (LJP) subjects exhibited much lower titres of fimbriae-specific IgG (89 +/- 11 units), IgA (31 +/- 5 units) and IgM (17 +/- 3 units) antibodies. A similar response pattern was also seen in sera from normal subjects aged 35-41 years who practice normal oral hygiene, while sera of younger adults (aged 18-24) with superior hygiene did not have any antigen-specific antibodies. Analysis of IgG subclass anti-fimbriae responses revealed that the major response was IgG3 followed by IgG1, IgG2 and IgG4 in AP, RPP and gingivitis. Although lower, a similar pattern of IgG subclass titre was seen in LJP and normal subjects aged 35-41 years. When IgA subclass responses were measured in AP and RPP, higher titres of the fimbriae-specific response were noted with IgA1 when compared with IgA2. However, lower but approximately equal levels of fimbriae-specific IgA1 and IgA2 titres were seen in other PD groups. When anti-B. gingivalis LPS-specific responses were measured, the sera of AP patients contained high levels of IgG antibodies (2265 +/- 224 units) followed by IgA (411 +/- 90 units) and IgM (214 +/- 56 units). Further, IgG anti-LPS responses were mainly IgG2 followed by IgG4, IgG3 and IgG1. For IgA subclass responses, higher titres of anti-LPS-specific antibodies were noted in IgA2 subclass over IgA1. These results showed that higher anti-B. gingivalis antibody responses occur in PD when compared with healthy individuals and protein and lipid-carbohydrate antigens of B. gingivalis induce distinct patterns of antigen-specific IgG and IgA subclass responses.  相似文献   

4.
The reconstitution of the human cytomegalovirus (CMV) antibody response in CMV seropositive bone marrow transplant patients was investigated by comparing 11 patients whose donors were CMV seropositive with 8 whose donors were CMV seronegative. Evidence for primary or secondary responses to CMV was sought by determining IgG antibody avidity using an avidity index method, and antibody titre over a period of up to 3 years after transplant. For the patients whose donors were CMV seropositive, the results showed the characteristics of a secondary response, i.e., rising antibody titres of high avidity immediately after transplant. In contrast, the patients with CMV seronegative donors showed evidence of a primary antibody response usually occurring at about 250 days after transplant, i.e., rising antibody levels initially of low avidity maturing to high avidity over the following 100 to 200 days. It is concluded that a secondary response and hence transfer of humoral immunity had occurred in those patients whose donor was CMV seropositive, whereas a delayed primary response occurred in those patients whose donor was CMV seronegative. © 1996 Wiley-Liss, Inc.  相似文献   

5.
Of 147 patients with acute Q fever diagnosed during a major outbreak in Birmingham, England, in early summer 1989, 41 provided sets of sera which allowed us to make a detailed analysis of the primary humoral immune response. Antibody titers specific for Coxiella burnetii were measured by the complement fixation test and by an immunoglobulin M (IgM)- and IgG-specific indirect immunofluorescence test. The relative avidity of specific IgGs was determined by the indirect immunofluorescence test with and without treatment of antigen-antibody complexes with 8 M urea. The IgG subclass responses after primary infection and their avidities were also determined for a limited number of paired serum specimens. Specific IgM titers persisted for more than 6 months in the majority of cases and were therefore not a sufficient criterion for the diagnosis of recent infection. However, for serial samples the antibody titer ratios (IgG/IgM) and the ratios (IgG titer with treatment/IgG titer without treatment) that indicated relative avidity changed significantly, depending on the time postinfection. Within the IgG class, the C. burnetii-specific antibody response over time was almost exclusively represented by subclass 1 molecules, which thus showed affinity maturation.  相似文献   

6.
Serum immunoglobulin G (IgG), IgM, and IgG subclass responses to the RgpA-Kgp proteinase-adhesin complex of Porphyromonas gingivalis were examined by enzyme-linked immunosorbent assay using adult periodontitis patients and age- and sex-matched controls. Twenty-five sera from subjects with adult periodontitis (diseased group) and 25 sera from healthy subjects (control group) were used for the study. Sera and subgingival plaque samples from 10 sites were collected from each patient at the time of clinical examination. The level of P. gingivalis in the plaque samples was determined using a DNA probe. Highly significant positive associations between the percentage of sites positive for P. gingivalis and measures of disease severity (mean pocket depth, mean attachment loss, and percentage of sites that bled on probing) were found. The diseased group had significantly higher specific IgG responses to the RgpA-Kgp complex than did the control group, and the responses were significantly associated with mean probing depths and percentage of sites positive for P. gingivalis. Analysis of the IgG subclass responses to the RgpA-Kgp complex revealed that the subclass distribution for both the diseased and control groups was IgG4 > IgG2 > IgG3 = IgG1. The IgG2 response to the complex was positively correlated with mean probing depth, whereas the IgG4 response was negatively correlated with this measure of disease severity. Immunoblot analysis of the RgpA-Kgp complex showed that sera from healthy subjects and those with low levels of disease, with high IgG4 and low IgG2 responses, reacted with the RgpA27, Kgp39, and RgpA44 adhesins; however, sera from diseased subjects with low IgG4 and high IgG2 responses reacted only with the RgpA44 and/or Kgp44 adhesins. Epitope mapping of the RgpA27 adhesin localized a major epitope recognized by IgG4 antibodies in sera from subjects with high IgG4 and low IgG2 responses to the RgpA-Kgp complex which was not recognized by sera from diseased subjects with low IgG4 and high IgG2 responses.  相似文献   

7.
The significance of serum IgG and IgA antibodies to cytomegalovirus (CMV) at various stages of human immune deficiency virus (HIV) infection was studied in 175 homosexual men. Sera were obtained from 123 HIV seropositives [41 asymptomatic, 29 with lymphadenopathy associated syndrome (LAS), 22 with AIDS related complex (ARC), and 31 AIDS patients], 17 HIV seroconverters, and 35 HIV asymptomatic seronegatives. The sera were tested blindly for CMV IgA and IgG antibodies using the immunoperoxidase assay (IPA) and CMV infected human embryo cells. Cross-sectional analysis of CMV IgG antibodies at a titer of greater than or equal to 20 showed 87% and 100% prevalence in the HIV seronegative groups and in the HIV seropositive groups, respectively (P less than 0.05). CMV IgG antibodies at a titer of greater than or equal to 80 were present in significantly higher proportions among the HIV seropositive subjects of the various groups as compared with the HIV seronegative homosexual men. However, in the HIV seronegatives who later seroconverted to HIV, a significantly higher prevalence of CMV antibodies (35%) was detected before HIV seroconversion, as compared with the persistently HIV seronegative subjects (14.3%) (P less than 0.05). The HIV seronegatives pre-HIV seroconversion also exhibited a significantly higher geometric mean titer (GMT) of CMV IgG antibodies (62.17 +/- 0.64) as compared with the persistently HIV seronegatives (34.0 +/- 0.6) (P = 0.03). Significantly higher GMTs of CMV IgG antibodies were detected in all the HIV seropositive groups as compared with the persistently HIV seronegative group. CMV IgG antibodies were not detected in the HIV seronegative subjects.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

8.
目的:评价结合四环素的牙周非手术治疗对侵袭性牙周炎(AgP)患者牙周附着水平(AL)和血清抗牙龈卟啉菌(Pg)抗体亲和力水平的影响。 方法:研究对象由25名侵袭性牙周炎患者、20名牙周健康者(HS)组成。AgP患者在接受机械性牙周治疗后给服四环素(0.5 g/d),3个月疗程结束后对病人进行评估。牙周治疗前及治疗3个月、6个月和12个月后常规临床检查、记录牙周附着水平,通过硫氰酸铵分离试验测定血清抗牙龈卟啉菌脂多糖(LPS)的抗体亲和力。 结果:牙周治疗后,牙周附着水平有显著改善(P<0.01);AgP患者血清抗Pg抗体亲和力明显下降(P<0.01)。 结论:结合四环素的机械性牙周治疗能显著降低AgP患者血清抗Pg抗体的亲和力对侵袭性牙周炎可获得满意的疗效。  相似文献   

9.
In the present study we sought to determine whether serum antibody was present against microorganisms which predominate in the subgingival flora of young adults with generalized severe periodontitis (SP). Subjects with SP were often seropositive for Eubacterium brachy, Fusobacterium nucleatum E3C22, and Peptostreptococcus micros, whereas subjects with juvenile periodontitis (JP) and subjects with healthy periodontium (HP) were not. Both SP and JP subjects were more frequently seropositive for Bacteroides gingivalis, F. nucleatum D52B16, and F. nucleatum E1D1 than were HP subjects. The data were most striking for B. gingivalis, for which both the incidence and the magnitude of specific antibody was clearly elevated for SP and JP subject groups. However, SP subjects generally had either a high antibody titer or no detectable titer. In contrast, JP and HP subjects generally had at least very small amounts of antibody. Except at very low levels of antibody, neither SP nor JP groups differed significantly from the HP group for antibody to Eubacterium nodatum, Bacteroides intermedius (homology group 4197 or 8944), or Lactobacillus minutus antibody. There was a high frequency of antibody to E. nodatum, with very high titers in all groups despite the fact that this organism is rarely found in HP subjects. For Eubacterium timidum, the JP group was clearly more frequently seropositive than the HP group. Despite high levels of L. minutus in subgingival flora, none of the 50 SP subjects had a detectable antibody titer, and only four of the HP and JP subjects had detectable antibody. These results indicate that many organisms in the subgingival flora elicit antibody responses. B. gingivalis is probably the best example among the species tested. However, some organisms that are present in high concentration, e.g., L. minutus, apparently fail to induce significant antibody responses.  相似文献   

10.
The presence of antibodies to the 60-kD human and Porphyromonas gingivalis GroEL hsp60 in the sera and inflamed gingival tissues of periodontitis patients was examined. In order to obtain the antigens, recombinant plasmids carrying human hsp60 and P. gingivalis GroEL genes were constructed and expressed as histidine-tagged recombinant proteins. Immunoreactivities of these proteins were confirmed by MoAbs specific to mammalian hsp60 and cross-reactive with both mammalian and bacterial hsp60. Western blot analysis clearly demonstrated that the number of periodontitis patients showing a positive response to P. gingivalis GroEL was higher than the number of periodontally healthy subjects. Furthermore, anti-P. gingivalis GroEL antibody was detected in all samples of gingival tissue extracts. For human hsp60, a higher frequency of seropositivity was found in the periodontitis patients than in the healthy subjects. In addition, the periodontitis patients demonstrated stronger reactivity compared with the healthy subjects. Quantitative analysis of serum antibodies by ELISA also demonstrated that the levels of antibodies in the sera of patients were significantly higher than those of control subjects. In the gingival tissue extracts, seven out of 10 patients demonstrated a positive response to human hsp60 and tso of these demonstrated strong positivity. Affinity-purified serum antibodies to human hsp60 and P. gingivalis GroEL from selected patients reacted with P. gingivalis GroEL and human hsp60, respectively, suggesting cross-reactivity of antibodies. These results suggest that molecular mimicry between GroEL of the periodontopathic bacterium P. gingivalis and autologous human hsp60 may play some role in immune mechanisms in periodontitis.  相似文献   

11.
T cells from patients with acute Plasmodium falciparum malaria were investigated for induction of immunoglobulin- or anti-malaria antibody secretion in vitro. Stimulation of autologous T/B cell mixtures (2T:1B) with low concentrations of P. falciparum antigen and cultured for 12 days gave rise to a T-dependent IgG secretion which was significantly elevated over that in medium controls. This was achieved with both a crude P. falciparum antigen and a partially purified preparation enriched in Pf 155, a merozoite-derived antigen deposited in the red cell membrane at invasion (Perlmann et al., 1984). Control antigen (RBC ghosts) induced IgG secretion only when added at high concentrations (greater than 10 micrograms/ml). Neither of the antigens induced IgG secretion at concentrations of less than or equal to 10 micrograms/ml in control cultures of lymphocytes from patients with P. vivax malaria. Supernatants from cultures of P. falciparum patients frequently contained anti-P. falciparum antibodies when nanogram quantities (10-100 ng/ml) of either one of the two malaria antigen preparations was used for stimulation. No anti-P. falciparum antibodies were induced by the control antigen at any concentration. The induced anti-P. falciparum antibodies were directed to intracellular parasites and. at lower frequencies, to Pf 155 as detected on the surface of infected erythrocytes. The induction in vitro of anti-P. falciparum antibodies appeared to be correlated with the presence of such antibodies in the sera of the lymphocyte donors. The lymphocytes of only one out of eight P. vivax patients responded to antigen stimulation by secreting anti-P. falciparum antibodies. However, this donor (but not any of the others), was also P. falciparum seropositive. Taken together, these results indicate that the induction of anti-P. falciparum antibody secretion reflects a secondary response in vitro of cells primed in vivo. The present experimental system should be well suited to map parasite antigen for their capacity to induce T cell dependent responses in P. falciparum malaria.  相似文献   

12.
The human IgG and IgA response was determined after vaccination with an experimental 24-valent Klebsiella capsular polysaccharide vaccine. The majority of natural antibody acquired prior to immunization was found in the IgG1, IgG2 and IgA1 subclasses. The immune response to vaccination was concentrated within the IgG1, IgG2, IgA1 and IgA2 subclasses with greater than or equal to 70% of subjects responding with a significant (greater than or equal to fourfold) rise in titer. The IgG3 and IgG4 response was meager with few volunteers (0%-40%) showing a significant titer rise. Therefore, vaccination with Klebsiella capsular polysaccharide induces a vigorous IgG and IgA response in humans which is not restricted to single antibody class or subclass.  相似文献   

13.
The protective effect of measles immunization is due to humoral and cell-mediated immune responses. Little is known about cell-mediated immunity (CMI) to measles vaccine virus, the relative contribution of CD4(+) and CD8(+) T cells to variability in such immune responses, and the immunologic longevity of the CMI after measles vaccination in humans. Our study characterizes cellular immune response in subjects seronegative or highly seropositive for measles vaccine immunoglobulin G-specific antibody, aged 15 to 25 years, previously immunized with two doses of measles-mumps-rubella II vaccine. We evaluated the ability of subjects to respond to measles vaccine virus by measuring measles virus-specific T-cell proliferation. We examined the frequencies of measles virus-specific memory Th1 and Th2 cells by an ELISPOT assay. Our results demonstrated that proliferation of T cells in seronegative subjects was significantly lower than that for highly seropositive subjects (P = 0.003). Gamma interferon (IFN-gamma) secretion predominated over interleukin 4 (IL-4) secretion in response to measles virus in both groups. The median frequency of measles virus-reactive CD8(+) T cells secreting IFN-gamma was 0.09% in seronegative subjects and 0.43% in highly seropositive subjects (P = 0.04). The median frequency of CD4(+) T cells secreting IL-4 in response to measles virus was 0.03% in seronegative subjects and 0.09% in highly seropositive subjects (P = 0.005). These data confirm the presence of measles virus-specific cellular immune responses post-measles vaccine immunization in humans. The detection of measles virus-induced IFN-gamma and IL-4 production by ELISPOT can be used to identify measles virus-specific low-frequency memory T cells in subjects immunized with measles vaccine. These differences agree in directionality with the observed antibody response phenotype.  相似文献   

14.
Sera from healthy seropositive donors, patients with acute measles, subacute sclerosing panencephalitis, common variable immunodeficiency, and CH gene deletions were analysed for anti-measles IgG1-4. Compared with other anti-viral immune responses of IgG1 and IgG3, an unusual predominance of specific IgG1 prevailed; only four out of a total of 68 patients showed anti-measles IgG3. Of the 17 healthy, measles seropositive serum donors, all showed specific IgG1, none showed IgG3 and six had IgG4. Eight out of 10 patients with SSPE showed an anti-measles IgG1 and IgG4 response while IgG3 was not seen. The IgG1 and IgG4 subclass patterns had some exceptions. Anti-measles IgG3 was found in five out of five patients with deletion of the gamma-1 encoding gene segments and in four out of 15 patients with recent measles antigen stimulation. The subclass pattern was suggested to reflect the immunological compromise associated with measles infections.  相似文献   

15.
The present study compared the effect of a single or a repeat challenge with the Gram-negative pathogen Porphyromonas gingivalis on the local inflammatory response within subcutaneous chamber model in mice. Subcutaneous chambers were implanted 2 weeks prior to the final challenge. The repeat-challenge (REP) group received two intrachamber bacterial injections 14 days apart, while the single-injection group (SIN) received only a single bacterial challenge. Injection of saline was used as the control. The cellular contents of the chamber exudates were used for differential cell counts, and the supernatants were analysed for tumour necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma), and interleukin (IL)-10 levels. Immunoglobulin G1 (IgG1) and IgG2a levels to P. gingivalis in the exudates were also determined. The results showed that the leucocyte counts increased significantly post-challenge, and the REP group showed the highest number of lymphocytes and neutrophils. Both P. gingivalis-challenged groups exhibited significant increase in TNF-alpha and IL-10 levels at day 1 post-challenge. TNF-alpha levels in the chamber exudate were threefold higher in the REP group compared with the SIN group on day 1 post-challenge (P < 0.05). In contrast, IL-10 levels were significantly lower in the REP group 1 day post-challenge compared with the SIN group. The REP group had significantly higher levels of IFN-gamma at baseline, and this difference remained significant 1 day post-challenge. Analysis of antibody levels to P. gingivalis showed that while the control and the SIN groups had no anti-P. gingivalis IgG in the chamber exudate during the 7-day study period, the REP group showed high anti-P. gingivalis IgG levels. In addition, the titres of IgG2a were fivefold higher than the IgG1 titres. The results showed that a repeat local challenge with P. gingivalis augmented the proinflammatory cytokines TNF-alpha and IFN-gamma, while inhibiting the accumulation of the anti-inflammatory cytokine IL-10. This shift towards a T helper 1 (Th1)-dominant response was reflected in the relatively high anti-P. gingivalis IgG2a titres in the local inflammatory environment 7 days post-challenge.  相似文献   

16.
A new method for analysis of virus-specific Immunoglobulin G (IgG) subclasses was developed using indirect immunofluorescence. Three hundred thirty-three serum samples from patients with different types of Epstein-Barr virus (EBV)-associated diseases and healthy controls were examined for subclass distribution to the virus capsid antigen (EBV VCA). EBV-VCA-expressing cell preparations were incubated with patient serum followed by monoclonal antibodies to human IgG1 through IgG4 and labelled anti-mouse IgG. Virus-specific IgG1 was found to be the dominant antibody. The titers for IgG1 and total Ig to EBV VCA correlated well. EBV VCA-specific IgG2 was not found. EBV VCA-specific IgG3 in a titer of greater than or equal to 10 was found in 33% of healthy seropositive donors, in 97% of patients with suspected reactivated EBV infection, and in 100% of symptomatic patients with suspected reactivated EBV infection. EBV VCA specific IgG3 occurred in 90% of placebo-treated compared to 30% in long-term acyclovir-treated bone marrow transplant recipients, indicating more frequent reactivations in the former group. IgG4 to VCA was infrequently found in seropositive persons. In serum samples from patients with nasopharyngeal carcinoma and high EBV VCA Ig and IgA titers, IgG4 to VCA was always present. Analysis of EBV VCA specific IgG subclasses seems to be valuable for the diagnosis of reactivated EBV infection.  相似文献   

17.
Herpes simplex virus (HSV)-specific IgG and IgA antibody response in patients with HSV infection and in healthy adults was studied by the immunoperoxidase antibody-membrane antigen (IPAMA) technique. In all HSV infections in which specific IgM antibodies were detected by enzyme-linked immunosorbent assay (ELISA), a significant rise in the titer of HSV IgG and IgA antibodies was found. In contrast, in patients with recurrent herpes labialis in which no specific HSV IgM antibodies were detected by ELISA, HSV IgG and IgA antibodies were not found to fluctuate significantly during the course of infection. A higher geometric mean titer (GMT) for HSV IgG and for IgA antibodies was found in seropositive individuals with a previous history of recurrent HSV than in seropositive individuals without a previous history of recurrent HSV infection. Nineteen of 26 HSV IgG seropositive healthy medical students without a previous history of recurrent HSV infection had HSV IgA antibodies to membrane antigen. The significance of this finding in understanding the mechanism of latency in healthy seropositive individuals without previous history of HSV recurrent infections is discussed.  相似文献   

18.
The infectivity and immunogenicity of live attenuated A/Washington/897/80 cold-adapted reassortant virus vaccine was evaluated in seronegative (hemagglutination inhibition titer, less than or equal to 1:4) and seropositive (hemagglutination inhibition titer, greater than 1:4) adult volunteers. The vaccine was efficient in infecting seronegative volunteers (94%). Moreover, 51% of seropositive vaccinees were infected by the virus. After live virus vaccination, greater than 83% of both seronegative and seropositive vaccinees achieved a level of nasal wash antibody previously associated with resistance to infection with influenza A virus. These findings indicate that both seronegative and seropositive vaccinees can benefit from live virus vaccination.  相似文献   

19.
Serum and stool samples were collected from 128 individuals: 96 diarrhea patients and 32 apparently healthy controls. Stool specimens were cultured for enteric bacterial pathogens, while sera were screened by enzyme-linked immunosorbent assay for Campylobacter jejuni-reactive antibodies. Of 28 diarrhea patients who demonstrated C. jejuni-reactive antibodies (titers, > 100), 14 were culture positive for this organism. The 32 healthy controls showed significantly lower antibody titers (P < 0.05) with the exception of 10 subjects who were culture positive for C. jejuni and had reactive immunoglobulin M (IgM) (6 subjects) and IgG (7 subjects). IgA was not detected in those 10 individuals (asymptomatic). Avidity was expressed as the thiocyanate ion concentration required to inhibit 50% of the bound antibodies. The avidity was higher in symptomatic patients than asymptomatic healthy controls. IgG was less avid (0.92 M) compared to IgM (0.1 M) and IgA (1.1 M), with no correlation between antibody titer and avidity. However, the thiocyanate ion concentration required for the complete inhibition of IgG (5 M)-bound antibodies was higher than that of IgA (2 M) and IgM (3 M). This study also shows that C. jejuni antibodies were variably cross-reactive with Escherichia coli, Shigella flexneri, Shigella sonnei, and Neisseria meningitidis in addition to Campylobacter coli and Campylobacter rectus.  相似文献   

20.
In this study, we describe the time course and T-cell dependence of the serum antibody response to the periodontopathogen Porphyromonas (Bacteroides) gingivalis in an experimental rat model. Normal Fischer rats were challenged by a local injection of P. gingivalis (2 x 10(8) bacteria) into gingival tissue or by the administration of a similar number of bacteria by the intravenous (i.v.) route on days 0, 2, and 4. Serum antibody activity was detected within 1 week and peaked at 8 weeks after gingival challenge. A similar but lower response was seen for rats challenged by the i.v. route. The response in both groups of rats was mainly of the immunoglobulin G (IgG) isotype; some IgM but no IgA antibody activity was detected. Analysis of the IgG subclass revealed mainly IgG2c in animals challenged locally in the gingiva with P. gingivalis, whereas IgG2b predominated in rats challenged by the i.v. route. The importance of T cells in the response was established by demonstrating the absence of serum IgG antibodies in nude rats after a local challenge of gingival tissue with P. gingivalis. Nude rats given purified splenic T cells from normal rats immunized systemically with P. gingivalis prior to a local gingival challenge showed a rapid appearance of serum antibody activity that peaked between 4 and 6 weeks. This initial peak occurred 2 to 4 weeks earlier than that seen in normal animals. Fluorescence-activated cell sorter analysis of splenic lymphoid cells from these nude rats revealed a helper T-cell population. The levels of serum IgG antibodies in nude rats given nonimmune T cells rose slowly, and the antibodies were mainly of the IgG2a and IgG2b subclasses. Nude rats given immune T cells showed a rapid increase primarily in IgG2b antibody levels following a local gingival challenge. These findings suggest that the immune helper T-cells contributed to the rapid development of the response to P. gingivalis. Furthermore, it is likely that the IgG subclass response to P. gingivalis in these nude rats was related to the splenic origin of the T cells used for adoptive transfer.  相似文献   

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