Isolation and partial characterization of Bermuda grass pollen allergen, BG-60a

In an earlier study we showed that Bermuda grass (Cynodon dactylon) pollen contains at least 12 IgE-binding proteins that can be analysed by immunoblot technique. One of the active components (BG-60) proved to be a basic protein of glycoprotein nature. It contained about 28% carbohydrate as determined from the dry weight and consisted of four molecules. One of the components was purified from the pollen extract by a combination of ammonium sulphate precipitation, ion-exchange chromatography on carboxymethyl-TSK, gel filtration on Ultrogel AcA 44 and chromatofocusing. Its molecular weight was approximately 60 kD by SDS-PAGE and 34 kD by gel filtration chromatography. The isoelectric point of the antigen was about 9.7. The homogeneity of the antigen BG-60a was assessed by one single arc of immunoprecipitation both in immunodiffusion and crossed immunoelectrophoresis and by one single band after SDS-PAGE. Its allergenicity was demonstrated by direct intradermal skin test on allergic patients and by examining IgE-binding reactivity with allergic patients' serum.

Isolation and partial characterization of Bermuda grass-pollen allergen: BG-60b

Our earlier studies have shown that the pollen of Bermuda grass (Cynodon dactylon)-pollen contain at least 12 IgE-binding proteins which can be analyzed by the immunoblot technique. One of the highly active components was found to be a basic protein with a molecular weight of 60,000 daltons, designated as BG-60. This component was showed to consist of a group of proteins. One of them, BG-60a (pI 9.7), has been isolated and characterized. In this study, we have further isolated and characterized the second component of the antigen, designated as BG-60b. Its purity was demonstrated by gel electrophoresis experiment and antigen-antibody precipitation studies. The antigen is of glycoprotein nature with a pI of 10.0. It exhibits IgE-binding activity and shows cross-reactivity to antigen BG-60a in double diffusion. Its chemical and physical properties are similar to antigen BG-60a.

[Parental attitude and adjustment to childhood epilepsy]

Parental attitude and adjustment were examined in 20 epileptic children (ages 6.8-16.6 yrs), using semi-structured interview. The results indicated that parental understandings of epilepsy were generally poor and incorrect. Fifteen (75%) of 20 parents had their own interpretations of causality and 19 (95%) had unrealistic hope for early and complete cure. Parents tended to overprotect and overrestrict their children. Sixteen (80%) concealed the illness for fear of social prejudice, therefore the social support systems were generally poorly utilized. As in other chronic diseases, all parents went through feelings of shock, denial, anger, guilt, fear, anxiety and depression. Family relationships were not affected much, however, poor communications were commonly found between parents and children. Thirteen (65%) parents never talked to their children about epilepsy. We concluded that parents of epileptic children showed negative attitudes toward their children and had difficulties in their psychosocial adjustment probably related to social stigmata and misunderstanding of the illness. Therefore, communication between physician and parents in both medical and psychosocial aspects should be encouraged.

Leukotriene release enhancing factor. Purification, specific allergen induction, and further biologic properties

Human PBMC cultured with PHA produced a factor which enhanced neutrophil LTB4 production. After progressive purification by gel filtration and chromatofocusing, leukotriene release enhancing factor (LREF) gave a single band on SDS-PAGE corresponding to a Mr of 60 kDa and a isoelectric point of 5.0 to 5.2. Human T lymphocytes were identified as a source of LREF because a long term human CD4+ T cell line, specific for house dust mite (Dermatophagoides farinae) generated leukotriene release enhancing activity (LREA) when stimulated with the inducing Ag together with irradiated accessory cells. Cultures of accessory cell and Ag alone did not induce neutrophil activation. Similarly, control cultures using an irrelevant allergen (grass pollen) failed to produce this activity. Stimulation of PBMC with anti-CD3 mAb also generated LREA. LREA had other neutrophil-associated biologic activities. These included the enhancement of neutrophil adherence to nylon wool, increased cytotoxicity of opsonised schistosomula of Schistosoma mansoni and upregulation of C receptors (CR1 and CR3). LREA had minimal neutrophil chemotactic activity. Therefore, LREF has potential as a mediator of inflammation and provides a link between lipid mediators, neutrophils, and cell-mediated immunity in the context of allergic diseases.

Leukotriene release enhancing factor. Purification, specific allergen induction, and further biologic properties

Human PBMC cultured with PHA produced a factor which enhanced neutrophil LTB4 production. After progressive purification by gel filtration and chromatofocusing, leukotriene release enhancing factor (LREF) gave a single band on SDS-PAGE corresponding to a Mr of 60 kDa and a isoelectric point of 5.0 to 5.2. Human T lymphocytes were identified as a source of LREF because a long term human CD4+ T cell line, specific for house dust mite (Dermatophagoides farinae) generated leukotriene release enhancing activity (LREA) when stimulated with the inducing Ag together with irradiated accessory cells. Cultures of accessory cell and Ag alone did not induce neutrophil activation. Similarly, control cultures using an irrelevant allergen (grass pollen) failed to produce this activity. Stimulation of PBMC with anti-CD3 mAb also generated LREA. LREA had other neutrophil-associated biologic activities. These included the enhancement of neutrophil adherence to nylon wool, increased cytotoxicity of opsonised schistosomula of Schistosoma mansoni and upregulation of C receptors (CR1 and CR3). LREA had minimal neutrophil chemotactic activity. Therefore, LREF has potential as a mediator of inflammation and provides a link between lipid mediators, neutrophils, and cell-mediated immunity in the context of allergic diseases.

T lymphocytes in allergen-induced late-phase reactions and asthma

We have studied a number of aspects of the interrelationship between T lymphocytes and allergic inflammation. Using monoclonal antibodies and immunocytochemistry we have observed significant infiltration by CD3+/CD4+ T lymphocytes together with evidence of T cell activation in the allergen-induced late-phase skin reaction in human atopic subjects. These changes were accompanied by eosinophil infiltration and activation. Activated T cells were also detected in the blood of patients with acute severe asthma. The role of T lymphocytes in granulocyte chemotaxis and activation was also explored, using recombinant human lymphokines, and we have identified and characterized two lymphokines which have specific effects upon neutrophils.

Antigen-induced neutrophil chemotactic factor from cloned human T lymphocytes

Here we report the presence of a low molecular weight (10,000 neutrophil chemotactic factor (NCF) in the supernatants of activated human T lymphocytes. Appreciable amounts of the 10,000 MW NCF were generated by peripheral blood mononuclear cells (PBMC) stimulated with anti-CD3 antibody, and comparable NCF was secreted by both long-term human T-helper (CD4+) cell lines reactive with house dust mite (Dermatophagoides farinae) and influenza A virus-immune T-cell clones. When the cloned T cells were stimulated with specific antigen in the presence of irradiated accessory cells (AC) or insolubilized anti-CD3 antibody the 10,000 MW NCF was readily identifiable in 24-hr culture supernatants. Cultures of AC and antigen alone produced negligible neutrophil chemotactic activity, as did control cultures using an irrelevant allergen (mixed grass pollen). These findings indicate that the 10,000 MW NCF may be T-lymphocyte derived and that formation and release are dependent upon stimulation via the antigen receptor.

A T-lymphocyte-derived factor that enhances IgG-dependent release of leukotriene B4 (LTB4) from human neutrophils

We describe a human blood mononuclear cell (MNC)-derived leukotriene release enhancing factor (LREF) which significantly increased IgG-dependent leukotriene B4 (LTB4) generation by neutrophils. MNCs incubated with phytohaemagglutinin (PHA) or anti-CD3 monoclonal antibody and PHA-stimulated ER+ lymphocytes produced a 150-350% increase in LTB4 generation from IgG-stimulated neutrophils. With PHA, maximal activity was observed 48 hr after culture in serum-free medium. LREF was relatively stable when exposed to low pH (pH 2) or heat (56 degrees, 60 min). Following progressive purification by gel filtration (FPLC, Superose 12) and chromatofocusing (FPLC, Mono P) LREF was associated with proteins of molecular weight of 35-40 kD and a pI of 5.1-5.5. Partially purified LREF did not contain detectable amounts of interleukin 2 (IL-2) or interferon-gamma (IFN-gamma). Although high concentrations of recombinant granulocyte-macrophage colony stimulating factor (rGM-CSF) (greater than 2 ng/ml) and recombinant tumour necrosis factor (rTNF) (greater than 100 U/ml) gave a slight (60%) enhancement of LTB4 generation, this was considerably less than that of partially purified LREF (350%). Our results suggest that human lymphocyte-derived LREF may play a role in the amplification of inflammatory reactions involving sensitized lymphocytes, neutrophils and lipid mediators.

The identification and partial characterization of a human mononuclear cell-derived neutrophil chemotactic factor apparently distinct from IL-1, IL-2, GM-CSF, TNF and IFN-gamma

We have identified a neutrophil chemotactic factor (NCF) in supernatants from human blood mononuclear cells (MNC) cultured in the presence of phytohaemagglutinin (PHA). Maximal activity was observed 48 hr after culture. Following gel filtration, NCF eluted as a single major peak, together with proteins, having a molecular size of approximately 10,000 MW. The material gave a single band on SDS-PAGE but was heterogeneous following chromatofocusing (pIs approximately 6.8-7.0, 5.5-6.0 and 5.0). The biological activity of the partially purified material was abolished by trypsin and chymotrypsin treatment. NCF was heat stable (70 degrees, 60 min) and promoted both directional migration (chemotaxis) of neutrophils and, to a lesser extent, stimulated random locomotion (chemokinesis). The factor was not associated with detectable amounts of IL-1, IL-2 or interferon-gamma (IFN-gamma). MNC-derived NCF had a molecular size lower than recombinant granulocyte-monocyte colony-stimulating factor (rGM-CSF) and recombinant tumour necrosis factor (rTNF), and was considerably more active in chemotaxis. Optimal chemotactic concentrations of partially purified MNC-derived NCF were of comparable potency to FMLP and LTB4 and had about 60% of the activity of optimal concentrations of C5a, C5a-des-Arg and platelet-activating factor (PAF). These experiments indicate that the human MNC-derived NCF is a potent chemo-attractant distinct from other cytokines previously reported to promote neutrophil locomotion.

Febrile seizures in patients with complex partial seizures

Febrile seizures occurred in 14 of 155 (9%) out-patients with complex partial seizures. Twelve patients had prolonged or recurrent febrile seizures, convulsive status epilepticus or a transient postictal neurological deficit. Febrile seizures were associated with perinatal abnormalities, an earlier onset of epilepsy and with a poor seizure control. Recurrent febrile seizures or those with complicating features are associated with an unfavourable therapeutic outcome in adult patients with complex partial seizures.

The effect of sodium on the biological activity of slow-reacting substances

Sodium can inhibit the specific binding of leukotriene D4 (LTD4) to its receptors. The effects of sodium on the biological activity of slow-reacting substance (SRS) which contains LTD4 are studied here. SRS was produced in leukocytes from seven normal donors. Its activity was bioassayed by guinea pig ileum contraction in an organ bath containing Tyrode's solution with 0.11 M NaCl. With higher concentrations of NaCl, the SRS-induced ileum contraction increased 45% at 0.14 M of NaCl (P less than 0.02), and 55% at 0.18 M NaCl (P less than 0.02). When NaCl concentration was increased to 0.21 M, the contractibility only increased 18% from the baseline (0.11 M NaCl), evidencing no statistical difference. The direct effect of changing NaCl solution from 0.11 to 0.21 M was to induce a significant ileum contraction with dose-related pattern.

Generalized tonic-clonic seizures in patients with complex-partial seizures: natural history and prognostic relevance

Clinical course and long-term seizure prognosis were studied in 155 patients with complex-partial seizures during a follow-up of 10.1 +/- 1 (SD) years. In 79% of the patients generalized tonic-clonic seizures were recorded, mostly within the first 3 years of epilepsy but occurring as late as 20 years after the onset of epilepsy. Seizure control was defined as complete absence of all seizures, including auras, for a minimum of 2 years. Seizure control occurred in 20 of 32 patients (63%) with complex-partial seizures only and in 76 of 123 patients (62%) with complex-partial seizures and generalized tonic-clonic seizures. The onset of the epilepsy with generalized tonic-clonic seizures or complex-partial seizures did not influence the therapeutic outcome despite differences in their natural history. A family history of epilepsy and other generalized seizures (e.g., absence) were more frequent in patients with generalized tonic-clonic seizures at the onset of epilepsy. Seizure control was significantly lower (44%) in patients with a history of a maximum frequency of one or more generalized tonic-clonic seizures per month when compared to patients (79%) with a total of less than six generalized tonic-clonic seizures (p less than 0.05). The frequency of generalized tonic-clonic seizures is of predictive value for the seizure prognosis of patients with complex-partial seizures.