Granulocyte-macrophage colony-stimulating factor enhances basophil histamine release induced by non-IgE-dependent stimulators

Some cytokines are known to affect IgE-mediated basophil histamine release. The effect of the cytokine granulocyte-macrophage colony-stimulating factor (GM-CSF) on human basophil and masct cell histamine release was studies further. Blood leukocytes with approximately 2% basophils from 9 healthy individuals were incubated with recombinant human GM-CSF (0.3–30 U/ml) in combination with A23187 (10^–7–10^–6 M) or washedStaphylococcus aureus whole bacteria (0.3–2.5 mg/ml). Histamine release was measured spectrofluorometrically. GM-CSF in itself did not induce histamine release. The addition of GM-CSF to cells stimulated with A 23187 caused a dose-dependent enhancement amounting to mean 70% at 3 U/ml and mean 170% at 30 U/ml (P<0.05). GM-CSF enhanced the bacteria-induced histamine release by 30% at U/ml and by 65% at 3 U/ml (P<0.05). The enhancement did not depend on cell-bound IgE or LPS contamination. In preliminary mast cell experiments with lung tissue we did not find an enancing effect of GM-CSF on IgE-mediated histamine release.     

Human T-cell subset changes during culture

When human peripheral blood lymphocytes (PBL) are cultured with either concanavalin A (Con A)-treated or control autologous T lymphocytes, the mitogenic responses of the PBL co-cultured with Con A-treated cells are much lower. We have investigated the cell surface receptor changes during culture of T cells with and without mitogen in an attempt to explain this differential regulatory phenomenon. We present data here which show that human T cells cultured in complete medium alone gain helper cells with time. Con A-treated T cells are known to lose helper cells during culture. Erythrocyte rosette-purified T cells were cultured with or without Con A for 84 h and the numbers of cells with receptors for the Fc regions of either IgM (T mu) or IgG (T gamma) were enumerated daily. T mu cells have been associated with helper activity while T gamma cells have predominantly suppressor activity. Treatment with 10 micrograms/ml of Con A decreased T mu by approximately 50%. Untreated cells, however, showed significant increases in T mu (44 +/- 30.5% in twelve individuals). The great variance in T mu increases is due to the fact that individuals having higher initial T mu values showed smaller increases. These changes probably represent the gain or loss of receptors because total cell numbers did not change. There was no significant change in the number of T gamma cells in either control or Con A-treated cultures during the same 84 h period. In co-culture experiments in which the responses of fresh autologous PBL were determined, 60-h control T-cell cultures enhanced the mitogen responses of the fresh cells.(ABSTRACT TRUNCATED AT 250 WORDS)     

Immunochemical cross-reactivity between albumin and solid-phase adsorbed histamine

For production of an antibody against histamine, this was coupled to human serum albumin (HSA) and used for immunization of rabbits. To test the antiserum, an immunoradiometric assay was developed comprising solid-phase bound histamine, antisera and radiolabelled protein A. Titration and inhibition experiments revealed that histamine adsorbed onto a solid-phase could bind the antiserum. However, neither free histamine nor histamine coupled to unrelated carriers could inhibit the binding of antiserum to the solid-phase histamine. Cross-reactivity was demonstrated between HSA and solid-phase bound histamine, as the immunoradiometric assay was inhibited by HSA. This unexpected cross-reactivity was established, as a commercially available antiserum with specificity to HSA without histamine also bound to the solid-phase bound histamine. It is suggested that preparations of antibodies against histamine are tested for this possible cross-reactivity.     

Inhibition of C5 or absence of C6 protects from sepsis mortality

Inhibiting complement anaphlytoxin C5a during sepsis may prevent sepsis mortality. Although human anti-C5 antibodies exist, their therapeutic use in microbial sepsis has been avoided because of the hypothesis that inhibiting C5b will prevent formation of the bactericidal membrane attack complex (MAC) and worsen clinical outcome. We wished to test the hypothesis that inhibition of C5 would improve outcomes in sepsis. Sepsis was induced in rats by laparotomy and cecal ligation and puncture (CLP) by an IACUC-approved protocol. Sham animals underwent laparotomy without CLP. Following CLP rats were randomized to receive a single IV dose of purified IgG ant-C5 antibody (Ab) or control IgG Ab. Anti-C5 Ab treated rats (n = 20) had significantly lower mortality vs. controls (n = 21), 20% vs. 52% (P = 0.019, log-rank). Analysis of bacterial load by culture of spleen and liver homogenates showed a reduction in colony forming units in anti-C5 Ab treated rats vs. control IgG (P = 0.003 and 0.009, respectively). Anti-C5 treatment reduced lung injury as measured by total MPO content of lung tissue (P = 0.024). Finally, rats genetically deficient in C6 production, unable to form MAC but capable of producing C5a and C5b, were protected from CLP-induced sepsis mortality. Our results show that in anti-C5 antibody therapy prevents CLP sepsis-induced mortality and improves lung injury. Inhibition of the complement MAC does not increase bacterial load or mortality, therefore, the use of anti-C5 therapy may be beneficial rather than detrimental in sepsis.     

Basophil histamine release in the diagnosis of house dust mite and dander allergy of asthmatic children

The aim of the study is to compare the glass fibre-based basophil histamine release test with skin test (Phazet), RAST (Phadebas) and bronchial provocation test in children with allergic asthma. The study comprised 68 selected children with a case history of extrinsic allergic asthma to danders (cat and dog) and house-dust mite. Skin prick test, RAST, and histamine release were performed in all children and the bronchial provocation test was used as a reference of "true allergic asthma". A total of 81 allergen bronchial challenges were performed and 44 children experienced 49 positive provocations. In 2.9% (2/68) of the children histamine release could not be performed due to technical difficulties (low histamine release with anti-IgE). Concordances in the range 76-87% were observed with no significant difference between the tests. The highest concordance (87%) was found between histamine release and bronchial provocation test followed by skin prick test vs bronchial provocation (84%) and RAST vs bronchial provocation (80%). The sensitivity and specificity were calculated for each test. All tests showed sensitivities in the range 90-94% and no significant difference between them was observed. The specificity of histamine release, skin prick test, and RAST was 0.78, 0.69, and 0.63, respectively. The specificity of histamine release was better than RAST demonstrated by 95% confidence intervals. In conclusion, it was found that the histamine release test is a convenient diagnostic method and the study indicates a diagnostic value comparable to the common diagnostic methods in clinical allergy.     

Der Stoffwechsel bei vollständigem Fasten. Unterschiedliches Verhalten bei Männern und Frauen sowie bei Normalpersonen und Adipösen

Zusammenfassung Bei 24 idealgewichtigen und 24 adipösen Personen beiderlei Geschlechts wurden zirkulierende Substrate (Blutzucker, freie Fettsäuren, Ketonkörper) und Hormone (Insulin, Wachstumshormon, Pankreasglukagon) während sechstägigem Fasten bestimmt. Der Blutzucker sank bei Normalpersonen unter Nulldiät auf tiefere Werte als bei Adipösen. Der Konzentrationsanstieg der freien Fettsäuren und Ketonkörper erfolgte bei Normalgewichtigen rascher als bei Fettsüchtigen und bei Frauen rascher als bei Männern. Das Plasmainsulin fiel bei Adipösen stärker ab als bei Normalpersonen. Alle untersuchten Gruppen wiesen nach 1–3 Fastentagen einen signifikanten Anstieg des Pankreasglukagons auf, dieser erfolgte jedoch bei normalgewichtigen Frauen rascher als bei Männern. Wachstumshormon (GH) stieg bei normalgewichtigen Männern unter Nulldiät signifikant an, bei adipösen Männern jedoch nicht. Bei z.T. auffallend hohen Nüchternwerten zeigten normalgewichtige Frauen keinen signifikanten GH-Anstieg, jedoch signifikant höhere GH-Konzentrationen als adipöse Frauen nach 1–6 Fastentagen. Ausgehend von den allen untersuchten Gruppen gemeinsamen Stoffwechselveränderungen bei Nulldiät werden die diesbezüglichen Unterschiede zwischen männlichen und weiblichen sowie zwischen normalgesichtigen und adipösen Personen diskutiert.     

Urticarial vasculitis, immune complex disease, and an infected ventriculoatrial shunt

Shunt nephritis syndrome consists of glomerulonephritis, mixed cryoglobulinemia, and persistent bacteremia. A 37-year-old woman with a prior history of a ventriculoatrial shunt presented complaining of urticaria. A skin biopsy specimen from one lesion showed findings consistent with vasculitis. Because microscopic hematuria was seen on urinalysis, systemic disease was suspected. The ensuing diagnostic workup revealed the syndrome of "shunt nephritis." To our knowledge, cutaneous findings of urticaria and vasculitis have not been previously reported in this interesting syndrome.