Dermal mast cell responses in Paragonimus westermani-infected mice

This study was carried out to determine whether dermal mast cell responses to Paragonimus westermani in an abnormal host, the mouse, were dependent on the site of metacercarial inoculation. In mice during subcutaneous infection, the number of dermal mast cells were increased significantly (p < 0.05) at the first week (38.3/mm2) and then persisted at a high level until the sixth week (45.2/mm2) of infection compared with PBS-injected (control) mice (range: 19.4-25.1/mm2). In mice during oral infection, the number of dermal mast cells were increased significantly (p < 0.05) at two weeks (33.5/mm2) after infection and remained at these levels thereafter compared with non-infected (control) mice (range: 17.4-22.3/mm2). In mice both during subcutaneous and oral infection, the recruited dermal mast cells showed extensive degranulation at the second week (68.4% and 60.7%, respectively), reached a peak at the third week (81.4%, and 92.1%, respectively) and then declined slightly thereafter. By contrast, in both control mice, about 10% of dermal mast cells were degranulated. In conclusion, this study suggests that dermal mast cell responses to P. westermani in mice are dependent on cutaneous sensitization by larval excretory-secretory antigens, irrespective of infection route.

Effects of anti-IgE mAb on serum IgE, Fc epsilon RII/CD23 expression on splenic B cells and worm burden in mice infected with Paragonimus westermani

It is generally accepted that parasite-specific IgE plays a crucial role in host defense against helminthic parasites. However, the role of high levels of nonspecific IgE in helminthic infections is still controversial. To investigate the role of nonspecific IgE in primary infections with P. westermani, the effect of anti-IgE mAb treatment on serum IgE, Fc epsilon RII/CD23 expression and worm burden in Paragonimus-infected mice were examined. In mice treated with anti-IgE antibody, the total IgE levels were not detectable (1 microgram/ml) throughout the experiment compared with untreated infected mice. The mean percentages of Fc epsilon RII/CD23 positive splenic B cells in anti-IgE treated mice (range: 20.3 - 30.5) were also decreased throughout the experiment compared with untreated infected mice (range: 35.7 - 44.4). Reduction of the total IgE and expression of Fc epsilon RII/CD23 on splenic B cells resulted in decreased worm burden six weeks post infection. These results suggest that high levels of nonspecific IgE in mice with primary infections of P. westermani play a harmful, rather than beneficial, role for the host, perhaps by interfering with CD23-dependent cellular pathways.

Degradation of human immunoglobulins and cytotoxicity on HeLa cells by live Trichomonas vaginalis

The present study was undertaken to determine whether live T. vaginalis degrades human secretory IgA, serum IgA and IgG molecules. Human immunoglobulins were exposed to live trophozoites, parasite lysate, and excretory-secretory product (ESP) of T. vaginalis. To determine the fragmentation of immunoglobulins, the reaction sample was subjected to SDS-PAGE and EITB, and peroxidase conjugated antihuman IgA and IgG were used as probes. Live trophozoites degraded secretory IgA. Serum IgA and IgG, and degradation were pressed forward by the prolongation of the incubation time and by increasing the number of trichomonads respectively. Also the lysates and ESP of trichomonads degraded IgA and IgG. The cysteine and serine proteinase inhibitors such as E-64, antipain, iodoacetic acid, iodoacetamide, TLCK reduced the ability of cleaving immunoglobulins. The proteinase activity and cytotoxicity of T. vaginalis to HeLa cells were decreased when live T. vaginalis was treated with metallo-proteinase inhibitor as well as cysteine and serine proteinase inhibitors. These results suggest that proteinase secreted from live T. vaginalis may play a part role in host pathogenesis by T. vaginalis, and the cleaving ability of host immunoglobulins by the proteinase may contribute as a one of immune evasion mechanism for parasite survival in the host.

Production of interferon-gamma and interleukin-4 by splenocytes in mice infected with Paragonimus westermani

The TH cytokine responses of spleen cells stimulated with Con A from mice infected with Paragonimus westermani were examined. The spleen cell culture supernatants were assayed for TH1-specific IFN-gamma and TH2-specific IL-4. Cytokine responses for IL-4 peaked at three days (410 +/- 60.9 pg/ml), persisted at a high level until the second week (343 +/- 59.0 pg/ml), and then decreased slowly four and six weeks after infection. IFN-gamma production by splenocytes only increased during the first week (151 +/- 32.3 pg/ml) and declined abruptly after the second week of infection. IFN-gamma production by splenocytes of infected mice was not observed during the sixth week of infection. In addition, serum IL-4 and IFN-gamma were measured. Serum IL-4 was not detected in substantial quantity until four to six weeks after infection. The time course of serum IL-4 was not correlated with that of IL-4 production by splenocytes. Serum IFN-gamma was undetectable during the entire course of infection. These results suggest that TH2 cytokine responses, rather than TH1, predominate in mice infected with P. westermani.

1991 cancer incidence in Seoul, Korea: results of the Implementation Study of the Seoul Cancer Registry

This article presents the results of the Implementation Study of the Seoul Cancer Registry, which started in July, 1991 as a population based cancer registry in Seoul, Korea. The completeness and validity of the registered data were evaluated using Mortality/Incidence ratio (M/I ratio), Histologically Verified Cases (HV%), Primary Site Uncertain (PSU%), and Age Unknown (Age UNK%). Owing to the additional active surveillance, the completeness of the data turned out to be fairly acceptable, except for the aged over 75(Mortality/Incidence ratio was over 100%). Eventhough the Seoul cancer registry(SCR) has further way to go in the completeness especially among elderly persons, the validity of SCR data was also acceptable in terms of HV%, PSU%, and Age UNK%. However, PSU% and Age UNK% might need to be further reduced to be comparable with other well established cancer registries. The age standardized incidence rates(ASR) of all cancers between July 1, 1991 and June 30, 1992 were 232.4/100,000 in males and 147.9/100,000 in females. The top five major sites of cancers in Seoul were the stomach, liver, lung, colo-rectum, and bladder in order in males, and the uterine cervix, stomach, breast, colo-rectum, and liver in females. Those 5 cancer sites comprised 68.9% and 64.7% of the total cancer incidence in males and females, respectively.

Nasal allergen challenge generates 1-0-hexadecyl-2-lyso-sn-glycero-3-phosphocholine

We studied antigen-induced platelet activating factor and the 1-0-hexadecyl-2-lyso-sn-glycero-3-phosphocholine (lyso-PAF) in nasal lavage fluids (NLF) by combined gas chromatography/mass spectrometric analysis (GC/MS). During the early allergic reaction, there was a dramatic increase in the levels of lyso-PAF that peaked at 15 min (2.6 +/- 5.2 ng/ml, mean +/- SEM, n = 6). Increasing doses of antigen produced a dose-dependent increase in the levels of lyso-PAF that peaked at the highest dose. Levels of lyso-PAF correlated strongly with those of N-alpha-tosyl-L-arginine methyl ester (TAME)-esterase activity (rs = 0.82, p = 0.0001) and histamine (rs = 0.57, p = 0.002). There was a no significant increase in the quantity of lyso-PAF found in NLF from allergic individuals challenged with diluent or nonallergic individuals challenged with antigen. In subjects showing a late phase reaction, as indicated by symptoms and histamine release, we detected lyso-PAF along with TAME-esterase activity and histamine during the late phase reaction. In contrast to lyso-PAF, PAF levels were near or below the detection limit of the assay in NLF and remained unchanged after antigen challenge. We also investigated the potential pathways for lyso-PAF generation from 2-acetylated phospholipids. We found that the time required for deacetylation of 50% of [3H]PAF (t1/2) to lyso-PAF was 50 min in baseline secretions and 10 and 22 min in NLF obtained 10 min and 24 h after antigen challenge, respectively. These data suggested that catabolic pathways were present in NLF.(ABSTRACT TRUNCATED AT 250 WORDS)

Changes of IgE production, splenic helper and suppressor T lymphocytes in mice infected with Paragonimus westermani

Effects of Paragonims westermani infection were observed in mice on the change of serum IgE level, the number of peripheral eosinophils and the distribution of Thy 1.2+ (CD3), L3T4+ (CD4), and Lyt-2+ (CD8) splenic T lymphocytes without mitogen stimulation. BALB/c mice were infected with 20 metacercariae of P. westermani each. Total serum IgE increased at 3 weeks after the infection and reached a peak on week 4 and maintained high levels of IgE until the 23rd week. Peripheral eosinophil numbers increased at the second week and attained peak level on week 9. The frequency of L3T4+ (CD4) and Lyt-2+ (CD8) T lymphocytes decreased slightly until 4 weeks after the infection, but not significantly. Absolute number of L3T4+ and Lyt-2+ T lymphocytes, and the ratio of L3T4/Lyt-2 were not markedly changed over the period of observation. The frequency of Thy 1.2+ (CD3) T lymphocytes in the infected group slightly decreased until 4 weeks after the infection and showed significant reductions at the 2nd and 4th week of the infection (p < 0.05).

[Blastogenesis of splenic lymphocytes to specific antigens and PHA in Paragonimus westermani infected mice]

Paragonimus westermani is a common fluke in Korea. The present study aimed to observe the cell mediated immune response in experimental paragonimiasis of mice. The mouse (BALB/c) was orally inoculated with 40 metacercariae of P. westermani from Cambaroides similis. During the infection (1, 2, 4, 6 weeks) of mouse, blastogenic response of splenic lymphocytes to P. westermani adult antigen, metacercaria antigen, and PHA were observed. Sera from infected and noninfected mice added to normal mouse splenic lymphocytes with or without PHA. The blastogenic response of splenic lymphocytes to PHA was reduced after 1 week of infection. However after 6 weeks of infection, the response was restored to the control level. The blastogenic response of splenic lymphocytes to P. westermani adult or metacercaria antigen increased significantly on 1 week after infection, and maintained up to 6 weeks after infection. The response of non-infected mice was suppressed by addition of the infected mouse serum. The present results suggested that cellular immunity was involved in P. westermani infected mice and that P. westermani anti-serum inhibited proliferation of T lymphocytes.

The effect of azelastine on the early allergic response

To study the effect of azelastine on the immediate reaction to nasal allergen challenge, we performed a double blind, placebo-controlled cross-over clinical trial. Thirteen subjects with seasonal allergic rhinitis underwent nasal challenge with antigen 4 hr after a single oral 2 mg dose of azelastine. The response was monitored by counting the number of sneezes and by measuring the levels of histamine, prostaglandin D2, immunoreactive sulphidopeptide leukotrienes, kinis and TAME-esterase activity in recovered nasal lavages. After a single dose of azelastine, there was a significant reduction in sneezing (10 vs 2, P = 0.01) and in the median levels of recovered TAME-esterase activity (63.1 vs 17.5 c.p.m. x 10(-3), P = 0.01), immunoreactive sulphidopeptide leukotrienes (7.5 vs 2.1 ng/ml, P = 0.03) and kinins (1370 vs 251 pg/ml, P = 0.03), with no significant reduction in the median levels of histamine (3.7 vs 1.2 ng/ml, P = 0.2) and prostaglandin D2 (70 vs 70 pg/ml, P = 0.2) compared to placebo (numbers represent total increase over diluent challenge). These results suggest that azelastine does not inhibit mast cell activation but affects the consequences of released histamine, namely sneezing, increased vascular permeability and the generation of kinins. The results further suggest that other cells, in addition to mast cells, might be responsible for the generation of leukotrienes during the early allergic response, and that azelastine reduces their ability to generate this mediator or that inhibition of leukotriene release from mast cells occurs at lower drug concentrations.

[Serum IgE levels in rats infected with Paragonimus westermani]

Paragonimus westermani is a common fluke in Korea. The present study aimed to determine serum total IgE and specific IgG levels in experimental paragonimiasis of rats. Each Wistar rat was inoculated orally with 20-25 metacercariae of P. westermani from Cambaroides similis. Before and after infection (1, 2, 3, 4, 6, 8 weeks) of P. westermani, the blood was collected from the retro-orbital venous plexus of rats and kept serum at -70 degrees C. Serum total IgE and specific IgG levels were determined by the capture and conventional enzyme-linked immunosorbent assay, respectively. The results were as follows; 1. Serum IgE values were increased to 0.18 +/- 0.042 at 2 weeks, 0.28 +/- 0.151 at 4 weeks and 0.43 +/- 0.055 at 8 weeks after infection. The absorbances of non-infected rats ranged 0.07 +/- 0.021-0.12 +/- 0.025. 2. Specific IgG values were slightly increased at 3 weeks (0.20 +/- 0.032) and gradually increased up to 8 weeks (0.31 +/- 0.067) after infection. The absorbances of non-infected rats ranged 0.11 +/- 0.035-0.18 +/- 0.019. The present results suggested that P. westermani could elevate serum IgE and specific IgG antibodies in Wistar rats which were not a good definitive host.

[Detection of IgG and IgM antibodies with ELISA technique in human trichomoniasis]

The direct wet mount examination of vaginal secretion, widely applied for the diagnosis of Trichomonas vaginalis infection in woman patients, is rapid and economical, however, the sensitivity of this technique is not so high. In this study enzyme-linked immunosorbent assay (ELISA) was employed for the detection of serum anti-T. vaginalis IgG and IgM antibodies from 30 vaginal trichomoniasis patients and 30 non-infected healthy persons. The results were as follows: 1. Serum ELISA-IgG value was 0.37 +/- 0.134 (Mean +/- S.D.) in vaginal trichomoniasis patients and 0.21 +/- 0.054 in healthy controls (p less than 0.005), and the sensitivity and specificity of ELISA for serum IgG antibody were 70.0% and 96.7%, respectively. 2. Serum ELISA-IgM value was 0.33 +/- 0.177 (Mean +/- S.D.) in vaginal trichomoniasis patients and 0.11 +/- 0.051 in healthy controls (p less than 0.005), and the sensitivity and specificity of ELISA for serum IgM antibody were 70.0% and 96.7%, respectively. 3. The ELISA-IgG values showed a significant correlation with ELISA-IgM values (r = 0.77, p less than 0.005). With above results, it is assumed that ELISA is a reliable method for the diagnosis of T. vaginalis infection and simultaneous measurement of serum IgG and IgM with this technique is recommended.