Mechanisms of gastrointestinal immunoregulation and food induced injury to the gut.
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Food Hypersensitivity↗
Biomedical subjects
S Strobel
Publications and source records attributed to S Strobel.
Congenital self-healing Langerhans cell histiocytosis with persistent cellular immunological abnormalities.
We describe an infant who presented at birth with numerous haemorrhagic and encrusted skin lesions, hepatomegaly, lymphadenopathy, raised hepatic transaminases, leucopenia and thrombocytopenia. The diagnosis of Langerhans cell histiocytosis was confirmed by immunohistochemistry, which demonstrated the presence of CD1, S-100 and DR positive cells in the skin infiltrate. The skin lesions resolved spontaneously after 6 weeks but recurred at 3 months and again were self involuting with resolution by 9 months. Persistent circulating T-cell abnormalities, including T-cell lymphopenia and the presence and persistence of peripheral blood CD1 + cells were noted throughout the first year of life.
Cell Count↗
Mucosal mast cell activation patterns in the rat following repeated feeding of antigen.
Groups of rats previously sensitized systemically on day 0 with a low dose of ovalbumin (OVA) were gavaged daily with ovalbumin or bovine serum albumin or a mixture of both proteins from day 14 to 18. Blood samples were obtained pre- and post-challenge and serum levels of the rat mast cell protease II (RMCPII) determined by immunoassay. Release of this specific mucosal mast cell mediator was only observed in animals challenged with ovalbumin and the initial challenge released levels of RMCPII 15-fold higher than normal resting levels (P less than 0.001). Subsequent daily challenges evoked the release of significantly lower levels of mediator (P less than 0.001 relative to day 14), but with one exception each test group released significantly more RMCPII than the matched control group on each day (P less than 0.001-P = 0.015). An increased uptake of BSA 'bystander' protein was observed when OVA-sensitized animals were repeatedly gavage-challenged with OVA but there was no correlation with the release of RMCPII mediator. After a 9-day rest period the levels of RMCPII released 6 hr post-challenge on day 26 were still significantly lower (P = 0.004) than the levels of mediator released on day 14. In contrast, animals not previously challenged were still capable of releasing high levels of mediator at the time of first mucosal contact. The levels of RMCPII detected in the serum after enteral protein antigen challenge never exceeded 6000 ng/ml and were lower than those previously observed in parasitized rats following intravenous antigen challenge.
Anaphylaxis↗
The generation of a 'tolerogen' after the ingestion of ovalbumin is time-dependent and unrelated to serum levels of immunoreactive antigen.
In an attempt to investigate the molecular basis of the mechanisms underlying oral tolerance, we have evaluated the molecular and biological features of ovalbumin subjected to intestinal processing. Immunoreactive ovalbumin absorbed by the gut was measured by a sandwich ELISA at different times after feeding 25 mg ovalbumin to adult mice. Ovalbumin was detected as early as 5 min after the feed (36.7 +/- 16 ng/ml; mean +/- 1 s.d.) and reached maximal levels at 1 h (73.3 +/- 20 ng/ml). Pooled mouse serum, collected 5 min or 1 h after the feed, was transferred intraperitoneally into the naive recipients. Suppression of systemic delayed-type hypersensitivity (DTH) was found in mice receiving 0.8 ml of serum obtained 1 h after ovalbumin feeding but not when using serum obtained 5 min after feeding. In order to transfer samples containing similar levels of ovalbumin, an increased amount (1.3 ml) of serum collected 5 min post-feed was used in further experiments but again failed to induce DTH tolerance. Serum samples obtained 5 and 60 min after ovalbumin feeding were analysed by fast-protein liquid chromatography (FPLC) fractionation followed by ELISA. Both the charge characteristics and molecular weight of intestinally absorbed ovalbumin were indistinguishable from native ovalbumin. Although intact native ovalbumin is the only molecular species detected by ELISA, the results suggest that this has no role in the suppression of DTH responses.
Administration, Oral↗
Immunologically mediated damage to the intestinal mucosa.
This review discusses experimental and clinical evidence for the existence of immunologically mediated damage to the intestinal mucosa. The discussion of mechanisms of gastrointestinal immunoregulation and lymphocyte recirculation via recently described homing receptors is preceded by a summary of the basic structures of the gut-associated lymphoid tissues (GALT). The relevance of food-induced systemic hyporesponsiveness (oral tolerance) to the prevention of immunologically mediated damage to intestinal mucosa is discussed in the light of anaphylactic (Type I) and delayed type (Type IV) hypersensitivity reactions. Other, less well defined, mechanisms of allergic injury are also briefly discussed. It is postulated that the abrogation and/or modulation of orally induced tolerance is the pathogenetic mechanism underlying the induction of food-sensitive enteropathies.
Enteritis↗
Prognosis of chronic granulomatous disease.
The records of 28 patients with chronic granulomatous disease born over a 32 year period were reviewed. The characteristics of the group, and the frequency with which various clinical and laboratory features had been recorded, was assessed. Nine patients were known to have died, in most cases of progressive suppurative infection. Actuarial analysis showed 50% survival through the third decade of life. The long term survival of patients developing symptoms after the end of the first year of life was significantly better than that of patients whose illness started in infancy. Our data confirm that the severity of chronic granulomatous disease is not uniform, and that the prognosis for long term survival is better than that suggested in earlier reports. Early onset may be a poor prognostic sign and invasive aspergillosis is a life threatening complication. In the absence of curative treatment, trials to assess the effectiveness of interferon gamma are necessary and early antenatal diagnosis should be offered to as many affected families as possible.
Actuarial Analysis↗
Central nervous system involvement in the erythrophagocytic disorders of infancy: the role of cerebrospinal fluid neopterins in their differential diagnosis and clinical management.
In two children with familial erythrophagocytic lymphohistiocytosis accompanied by neurologic symptoms, total neopterin concentrations in cerebrospinal fluid were 200 times higher than in controls and 10 to 20 times higher than in five children with presumed neurologic disease due to primary viral infections (human immunodeficiency virus, herpes simplex, measles) of the CNS. In one child with familial erythrophagocytic lymphohistiocytosis, clinical remission was accompanied by a fall in neopterin concentrations to normal; in a second child, who died, total neopterin concentrations remained high. In two other children with a diagnosis of infection-associated hemophagocytic syndrome without any neurologic disturbance, neopterin concentrations were also elevated but only to 10 times the concentrations in controls. Total neopterin concentrations in cerebrospinal fluid provide a measure of the severity of macrophage infiltration and activation within the CNS, and are useful in assessing the need for intensive chemotherapy and monitoring the response to treatment.
Biopterins↗
The use of locus-specific minisatellite probes to check engraftment following allogeneic bone marrow transplantation for severe combined immunodeficiency disease.
The graft status of 14 patients, 13 of whom had received an allogeneic bone marrow transplant (BMT) for severe combined immunodeficiency disease (SCID) and one patient with SCID in whom intrauterine maternal engraftment was suspected, was examined using bone marrow or peripheral blood DNA and a combination of locus-specific minisatellite probes for the sex-matched and locus-specific and a Y specific probe for the sex-mismatched patients. The sensitivity of the assay systems was such that less than 0.1% recipient DNA was detectable in a background of donor DNA. Graft status could be satisfactorily documented by 2.5 weeks post-transplant and in one case was of particular value as immunological parameters were misleading. In the six long-term survivors of allogeneic BMT for SCID, the use of the locus-specific probes showed total donor lymphoid and myeloid haemopoietic engraftment in five cases and mixed host/donor populations in one case. The diagnosis in approximately 10% of cases of SCID may prove difficult due to engraftment of the fetus by maternal cells. Diagnosis may be facilitated by the use of the locus specific minisatellite probes and indeed we found specific evidence for such maternal engraftment in one patient at presentation. The combination of these probes together with a Y specific probe thus provides a rapid and accurate method of assessing graft take following allogeneic BMT for SCID. The simple pattern of inheritance obtained and the high level of sensitivity of detection of low numbers of allogeneic cells make the techniques amenable for use in any routine DNA diagnostic laboratory.
Bone Marrow Transplantation↗
Fatal graft versus host disease after platelet transfusions in a child with purine nucleoside phosphorylase deficiency.
Fatal graft versus host disease (GVHD) developed in a child with purine nucleoside phosphorylase (PNP) deficiency following an unirradiated platelet transfusion. IV treatment with an anti-T-cell monoclonal antibody (CD7) led to a transient improvement of his GVHD (Grade IV) but did not prevent the fatal outcome. This report emphasizes the need for blood products to be irradiated when cell mediated immunodeficiency is suspected, even in patients with residual immunocompetence.
Blood Transfusion↗
Neurodevelopmental delay and focal seizures as presenting symptoms of human immunodeficiency virus I infection.
Three children presenting with neurological symptoms were subsequently diagnosed as being infected with the human immunodeficiency virus I (HIV). All children showed normal development for about 12-18 months of age but later developed psychomotor and developmental regression. One child presented with generalised hypotonia, another with focal seizures, and the third with spastic quadriplegia. Two of the children showed areas of abnormal brain density on computed tomography and in one case there was calcification of the basal ganglia. In two of the children cerebrospinal fluid contained reduced amounts of total folate and elevated concentrations of neopterin. The possibility of a link between the deranged folate metabolism and the neurological symptoms in HIV infection is discussed.
Acquired Immunodeficiency Syndrome↗
Failure to induce oral tolerance to protein antigens in neonatal mice can be corrected by transfer of adult spleen cells.
We have examined the mechanisms that prevent the induction of oral tolerance to protein antigens in neonatal mice. Serum collected from adult mice 1 h after feeding ovalbumin (1 mg/g body wt) was adoptively transferred to mice aged 1, 3, and 42 d (40 microL/g body wt). Whereas delayed-type hypersensitivity was significantly suppressed in adult recipients relative to control groups, no suppression of systemic delayed-type hypersensitivity was found in neonatal recipients. In attempts to identify the immunologic deficiency that prevents mature reactivity to protein antigens in neonates, adult splenocytes were transferred intraperitoneally (10(8) cells/recipient) 24 h before a feed of OVA (1 mg/g body wt) to neonates. Significant suppression of their systemic DTH response, but not of their anti-ovalbumin IgG antibody response was observed, indicating that spleen cell transfer only partially confers adult-type reactivity. Similar results were obtained using a second protein antigen, BSA. Our observations suggest that the failure to induce oral tolerance to protein antigens in neonatal mice is not simply due to immature antigen processing by the gut, but probably reflects cellular and/or antigen handling immaturity of the neonatal immune system.
Administration, Oral↗
Mechanisms of lymphocyte adhesion to endothelial cells: studies using a LFA-1-deficient cell line.
In order to investigate the role of lymphocyte function-associated antigen 1 (LFA-1) in lymphocyte adhesion to endothelial cells (EC), we have studied the adhesion of a LFA-1-deficient lymphoblastoid cell line, ICH-KM, which has < 10% of the cell surface LFA-1 expressed on a normal lymphoblastoid cell line, ICH-BJ. The adhesion of ICH-KM cells to unstimulated EC was 49.9 +/- 8.6% (mean +/- SD) that of ICH-BJ cells. Moreover, phorbol ester-stimulated ICH-KM cells showed a considerably weaker increase in adhesion to unstimulated EC compared with ICH-BJ cells (mean +/- SD increase in percentage adhesion, 3.8 +/- 2.3 compared with 18.5 +/- 8.0; P<0.025). In contrast, there was no significant difference between the enhanced adhesion of ICH-KM cells and ICH-BJ cells to interleukin-1 (IL-1)-stimulated EC. Thus ICH-KM cells showed a 22.7 +/- 11.0 (mean +/- SD) increase in percentage adhesion to IL-1-stimulated EC compared with the 24.8 +/- 8.5 increase in percentage adhesion of ICH-BJ cells. Anti-LFA-1 monoclonal antibodies had no effect on the enhanced adhesion of ICH-KM and ICH-BJ cells to IL-1-stimulated EC but abolished the differences in adhesion between the two cell lines. The study therefore indicates that although a major part of unstimulated and phorbol ester-stimulated lymphocyte-EC adhesion is dependent upon LFA-1, the enhanced adhesion due to stimulation of EC with IL-1 is not dependent upon this molecule. The data therefore supports the existence of cytokine-inducible LFA-1-independent adhesion molecules for lymphocytes on EC.
Antibodies, Monoclonal↗
The kinetics of oral hyposensitization to a protein antigen are determined by immune status and the timing, dose and frequency of antigen administration.
We have investigated the immunological consequences of feeding a protein antigen to previously immunized animals. BALB/c mice were systemically primed with ovalbumin (OVA) in complete Freund's adjuvant (CFA) and fed with high (10 mg/g body weight), medium (1 mg/g body weight) or low (1 microgram/g body weight) doses of OVA once (Day 1, 7 or 14) or sequentially for 5 days (Days 1-5, 7-11, 14-18). The specific IgG antibody response was suppressed only by early feeds of high-dose OVA (Days 1-5). Medium-dose OVA fed on Day 14 or low-dose OVA fed at any stage after immunization enhanced the IgG antibody response. In contradistinction, systemic delayed-type hypersensitivity responses (DTH) were usually suppressed by early feeds of high or medium doses of OVA but never after feeding low-dose OVA. The results suggest that systemic DTH and IgG antibody responses to oral antigen are subject to different control mechanisms in previously primed animals. Such responses depend on the immune status of the animal and are controlled by antigen dose, time and frequency of feeding. The immunological effects observed are also demonstrable following adoptive transfer of spleen cells collected 14 days after multiple feeds of high-dose OVA to immunized mice. Our findings suggest that oral hyposensitization after systemic immunization is regulated by (suppressor) spleen cells which are activated by gut-processed antigen.
Animals↗
Triticone A: a novel bioactive lactam with potential as a molecular probe.
Triticone A is one member of a family of novel compounds which are spirocyclic lactams produced by several plant pathogenic fungi including Drechslera tritici repentis on wheat. It undergoes racemization to form triticone B and when tested, the enantiomeric mixture causes chlorosis and necrosis on a wide range of plants. Fluorescein diacetate treated protoplasts in conjunction with various triticone treatments allowed for accurate quantitation of the biological activity of the toxin. Various physiological functions of the wheat cell are impaired including the Hill and CO2 fixation reactions in photosynthesis. In addition, triticone A inhibits enzymes that have SH functional groups as part of their active site, eg., the protease-ficin. Neither triticone C or D had any activity in the enzyme or protoplast assays. It is apparent that triticone A has some potential as a molecular probe in a variety of biological systems.
Biological Assay↗
Response of LFA-1-deficient B cells to interleukin 4 (BSF-1) and low molecular weight B cell growth factor (BCGFlow).
T cell-depleted B cells from a patient with LFA-1 deficiency were tested in costimulation assays for responsiveness to recombinant human IL4 (BSF-1) and purified low molecular weight B cell growth factor (BCGFlow). In both cases the response of LFA-1-deficient B cells was comparable with normal controls. Monoclonal antibodies to LFA-1 alpha (CD11a) and beta (CD18) chains were unable to mimic the action of IL4 on normal B cells in costimulation assays with anti-IgM, and did not inhibit normal B cell proliferation in response to IL4 and anti-IgM. Epstein-Barr virus-transformed lymphoblastoid B cell lines (LCL) from normal and LFA-1-deficient donors both responded in proliferation assays to BCGFlow but not IL4. Similarly, both normal and LFA-1-deficient LCL increased IgM secretion in response to BCDF, BCGFlow and, interestingly, IL4. The normal LCL also increased IgG secretion in response to these factors, but no IgG was detected in supernatants from the LFA-1-deficient LCL. These results show that LFA-1 expression is not essential for B cell responses to B cell growth and differentiation factors.
Antibodies, Monoclonal↗
Dual meningoencephalitis with echovirus type 11 and adenovirus in combined (common variable) immunodeficiency.
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Adenoviridae Infections↗
'Processing' of antigen by the gut.
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Animals↗
Intestinal hypersensitivity reactions in the rat. I. Uptake of intact protein, permeability to sugars and their correlation with mucosal mast-cell activation.
We have confirmed previous observations that intestinal anaphylaxis induced in rats previously sensitized to ovalbumin (OVA) is associated with an increased uptake of an unrelated 'bystander' protein, bovine serum albumin (BSA) fed 1 hr previously. In this study, this enhanced protein uptake was associated with an increased lactulose/rhamnose excretion ratio after administration of these sugars, although there was no correlation between the two measurements. One hour after antigen challenge the serum levels of rat mast-cell protease II (RMCPII), a specific marker for mucosal mast-cell secretion, were significantly higher than both the pre-challenge levels and those of sham-challenged controls (P less than 0.002). There was a significant positive correlation between the serum levels of RMCPII and the lactulose/rhamnose excretion ratios (P less than 0.05), but no such correlation existed between RMCPII and BSA levels in the challenged rats. In other studies the urinary lactulose/rhamnose ratios of rats with cetrimide-induced gut damage were found to be significantly increased, although BSA uptake into the serum remained unaltered. We conclude that there is no simple correlation between gut permeation of low-molecular weight sugars and and the uptake of macromolecular proteins.
Animals↗