Chris H. Bridts

ACQUIRED IMMUNODEFICIENCY SYNDROME IN A HETEROSEXUAL POPULATION IN ZAIRE

38 patients with the acquired immunodeficiency syndrome (AIDS) were identified in Kinshasa, Zaire, during a 3 week period in 1983. The male to female ratio was 1.1:1. The annual case rate for Kinshasa was estimated to be at least 17 per 100 000. Opportunistic infections were diagnosed in 32 (84%) patients, disseminated Kaposis sarcoma (KS) with opportunistic infection in 5 (13%), and disseminated KS alone in 1 patient. Immunological characteristics of these patients were as reported for cases in the USA and Europe, but immunological abnormalities were also found in 6 controls with infectious diseases but no symptoms of AIDS. Female AIDS cases were younger than male patients with AIDS (mean ages 28.4 vs 41.1 years, respectively), and were more often single (14/18 vs 2/20). Homosexuality, intravenous drug abuse, and blood transfusion did not appear to be risk factors in these patients. The findings of this study strongly argue that the situation in central Africa represents a new epidemiological setting for this worldwide disease--that of significant transmission in a large heterosexual population. Two instances of clusters of AIDS (not included in the above series) involving males and females with frequent heterosexual contact further implicate heterosexual transmission.

Use of fluorescent dyes in the determination of adherence of human leucocytes to endothelial cells and the effect of fluorochromes on cellular function

A number of supravital fluorochromes are available to study leucocyte functions in vitro and in vivo. The fluorescein ester most widely used, fluorescein diacetate, has the disadvantage of rapid cellular efflux, whereas more recently developed fluorescent probes do not exhibit this inconvenient trait. However, their effect on cellular functions has not been thoroughly investigated in humans. In this study, we describe a simple and rapid fluorometric method for measuring cell adhesion to endothelium, comparing 5 different fluorochromes. Furthermore, we evaluated the effect of fluorescent dye labelling (with CFDA, CFSE, BCECF-AM, calcein-AM or DiI), on various cell functions, including, apart from adhesion, lymphocyte proliferation, granulocyte chemotaxis and superoxide production. calcein-AM and DiI proved to be the fluorochromes with the least effect on cellular function. BCECF-AM did not interfere with lymphocyte proliferation, but exhibited some influence on superoxide production and chemotaxis of granulocytes. CFDA showed a detrimental effect on both lymphocyte and granulocyte functions whereas CFSE gave intermediate results. In the adhesion assay, calcein-AM, CFSE and DiI performed comparably well. Since labelling with C12-DiI was homogeneous, this probe was also appropriate for the adhesion test, although somewhat higher background staining was present. We conclude that the fluorochromes are powerful tools when analysing the adhesion of human leucocytes to endothelial cells. However, since fluorochrome labelling can interfere with other cellular functions, the fluorescent probe has to be carefully chosen with regard to the cell type and function to be studied.

LEUKOCYTOSIS, MONOCYTOSIS AND NEUTROPHILIA: HALLMARKS OF SEVERE DEPRESSION

To date, there has been a small number of reports that severe depression is accompanied by disturbances in total white blood cell (i.e. leukocytosis) and leukocyte subset (i.e. neutrophilia, monocytosis, lymphopenia) counts. These results, however, have not yet been validated in a large-scale, well-controlled study. To this end, we have counted the number of leukocytes, monocytes, lymphocytes and granulocytes (neutrophils, eosinophils, basophils) in 22 healthy controls and in 109 depressed inpatients. We noted leukocytosis in major depressed patients compared with normal subjects, whilst minor depressives manifested intermediate findings. Leukocytosis was significantly more pronounced in major depressed males compared with major depressed females. Major depression related leukocytosis appears to be characterized by neutrophilia and monocytosis. There was a significant positive relationship between the overall severity of illness on one hand, and the degrees of leukocytosis, neutrophilia and monocytosis on the other. The total number of both phagocytic cell populations (i.e. monocytes and neutrophils) was significantly and positively related. Our results might point to the existence of an inflammatory process in major depressed subjects, particularly in males.

Flow cytometric analysis of in vitro activated basophils, specific IgE and skin tests in the diagnosis of pollen-associated food allergy

Specific immunoglobulin E (IgE) and commercially available skin prick tests have been demonstrated to be unreliable methods to diagnose pollen‐associated food allergy. To evaluate the predictive value of the basophil activation test (BAT) in pollen‐associated food allergy, the apple‐mediated oral allergy syndrome (OAS) in patients with birch pollinosis was chosen as a representative model.

Contact allergic dermatitis and life-threatening anaphylaxis to chlorhexidine.

A 43-year-old nonatopic man was seen with a history of dyspnea, shock, and S-T segment elevations in the inferior leads of his electrocardiogram after disinfection of a drain insertion site with a chlorhexidine digluconate 2% solution. His personal history revealed a similar reaction 15 minutes after anesthesia was achieved with a preoperative administration of cephazolin; application of povidone-iodine; and the use of propofol, atracurium, and sufentanil. Macromolecular plasma expanders were not infused, and exposure to chlorhexidine was not mentioned. He also recalled two episodes of a rash at surgical incision areas, which, in the presence of an infiltrated, papular, and vesicular patch test for chlorhexidine digluconate 0.5% solution and Hibitane, was diagnosed as contact dermatitis to the antiseptic. Total serum IgE was 480 kU/L. Serum-specific IgE test results for latex, ethylene oxide, chloramine, penicilloyl G, penicilloyl V, and amoxicillin (Upjohn-Pharmacia CAP System, Brussels, Belgium) were negative. Lymphocyte transformation test results with chlorhexidine (10 mg/ ml), sufentanil (0.005 mg/ml), vecuronium (10 mg/ml), atracurium (10 mg/ml), propofol (10 mg/ml), and cephazolin (10 mg/ml) were negative (stimulation index ,2). Skin prick test (SPT), intradermal test (IDT), and subcutaneous test results with nonammoniated latex (IDT, 10–3 mg/ml), alcohol 70% (SPT, undiluted), 100 mg/ml povidone-iodine (SPT, undiluted), 50 mg/ml cephazolin (SPT, undiluted), 2.5 mg/ml bupivacaine (subcutaneous test, undiluted), 10 mg/ml propofol (IDT, 10–2 mg/ml), 2 mg/ml etomidate (IDT, 10–2 mg/ml), 5 mg/ml sufentanil (IDT, 10–2 mg/ml), 4 mg/ml vecuronium (IDT, 10–2 mg/ml) and 10 mg/ml atracurium (IDT, 10–2 mg/ml) were negative. A SPT result with chlorhexidine digluconate 2% in alcohol 70% was positive (SPT 10–4, wheal/flare, 5/13 mm). Patch test results showed a delayed hypersensitivity to cetrimide 0.1%, chloroxylenol 1%, chloramine 0.5%, and iodine 0.25%, but they were negative for hexamidine 0.15%, thiomerosal 0.1%, Mercurochrome 2%, eosine 50%, and Chlorophen. DISCUSSION

Significantly increased expression of T-cell activation markers (interleukin-2 and HLA-DR) in depression : further evidence for an inflammatory process during that illness

1. Recently, the authors have reported that severe depression may be accompanied by a systemic immune activation with an increase in the number of T cells expressing activation receptors. 2. The present large-scale study examines specific T (CD2+HLADR+ and CD7+CD25+) and B (CD7-CD25+) cell activation markers in depressed inpatients and normal volunteers together with the number of leukocytes and monocytes. 3. The authors have established that depression is characterized by a significantly increased expression of T cell activation receptors (CD7+CD25+) and by the appearance of previously unexpressed T cell surface markers (CD2+HLADR+). There was a significant and positive correlation between the number of CD7+CD25+ cells and monocytes, with the expression of the HLADR and CD25 T cell activation markers being significantly and positively correlated. Up to 64% of all depressed subjects exhibit an increased expression of these activation markers with a specificity of 91%. 4. The normal control group and the depressive sample constitute two discrete classes (i.e., qualitatively distinct groups) with respect to the expression of these activation markers and leukocytosis. 5. It is concluded that our results are compatible with the presence of T-cell activation in a considerable number of depressed patients.

Increased IL-17 production by peripheral T helper cells after tumour necrosis factor blockade in rheumatoid arthritis is accompanied by inhibition of migration-associated chemokine receptor expression

OBJECTIVES The contribution of IL-17-producing Th17 cells to the pathogenesis of T-cell-mediated inflammatory disorders such as RA and atopic dermatitis (AD) has to be viewed in relation to the role of Th1/Th2 cells and long-recognized key cytokines like TNF. We aimed to study the frequency and migration-associated phenotype of peripheral Th17, Th1 and Th2 cells in healthy individuals, RA and AD patients, and to study the influence of anti-TNF therapy in RA. METHODS Intracellular IL-17, IFN-γ and IL-4 production and CC-chemokine receptor CCR4 and CCR6 expression were analysed flow cytometrically in peripheral memory Th cells from healthy individuals, AD and RA patients. The latter were grouped by disease activity and presence or absence of adalimumab therapy. In RA patients initiating anti-TNF therapy, cytokine production by in vitro-stimulated peripheral mononuclear cells was measured by cytometric bead array. RESULTS The peripheral Th17 cell frequency is elevated in AD but not in RA. In RA, Th17 cells and IL-17 production increase after anti-TNF therapy, irrespective of disease activity. Th1 cells and IFN-γ production are elevated in remission and under anti-TNF therapy. CCR6 expression is up-regulated in Th17 cells, but RA patients in remission under anti-TNF therapy have significantly lower expression than those with active disease. CONCLUSIONS The increase in peripheral Th17 cells in RA patients after anti-TNF therapy is accompanied by a decrease in Th17-specific CCR6 expression, which might prevent homing of these potentially pro-inflammatory cells to the synovium.

Latex-specific IgE, skin testing, and lymphocyte transformation to latex in latex allergy

BACKGROUND This study was designed to determine the discriminative value of latex-specific IgE tests, latex skin tests, and lymphocyte transformation tests (LTTs) to latex in 38 patients with latex allergy (12 nonatopic and 26 atopic) and 44 control subjects (24 nonatopic and 20 atopic). We also evaluated the recommended positive cutoff (i.e., 0.35 kU/L) of both in vitro latex-IgE tests. METHODS Latex-specific IgE levels were determined by the Immuno-CAP (Upjohn-Pharmacia) and the ALaSTAT-RIA (Diagnostic Products Corp.) assays. Skin tests and LTFs were performed with a nonammoniated latex extract (DPC). Sensitivities and specificities were defined according to the 95th percentile value of nonatopic control subjects. For the in vitro IgE tests, sensitivity and specificity were also calculated by using the proposed positive threshold of 0.35 kU/L. Sensitivities and specificities of both cutoffs were compared. RESULTS Compared with a clinical history of latex allergy and according to the 95th percentile value of nonatopic control subjects (0.44 kU/L), latex-specific IgE determined by the Immuno-CAP assay achieved a sensitivity of 97% and a specificity of 86%. For the ALaSTAT-RIA assay, with 0.54 kU/L as the 95th percentile threshold value in nonatopic control subjects, sensitivity was 100%, and specificity was 83%. According to the threshold value of 0.35 kU/L, a sensitivity of 97% and a specificity of 83% for the Immuno-CAP assay and a sensitivity of 100% and a specificity of 33% for the ALaSTAT-RIA assay were observed. The latex skin test reached a sensitivity of 97% and a specificity of 100%. The LTF to latex showed a sensitivity of 39% and a specificity of 95%. No relation between symptoms and latex-specific IgE tests, latex skin tests, or LTTs was found. CONCLUSIONS Our results confirm that latex skin tests and latex-specific IgE assessments are sensitive and specific methods for establishing the diagnosis of latex allergy, although the specificity of the ALaSTAT-RIA assay was very low when interpreted according to the threshold of 0.35 kU/L. The LTT to nonammoniated latex is too insensitive for diagnosis of allergy to latex. This reemphasizes that in order to evaluate the sensitivity and specificity of diagnostic procedures, one should always include an appropriate control group.

Activated T cells complicate the identification of regulatory T cells in rheumatoid arthritis.

Most cell surface markers for CD4(+)CD25(+) regulatory T cells (Tregs) are also expressed by activated non-regulatory T cells. Recently, CD127 down-regulation was found to identify functional Tregs in healthy individuals, but there are no data from patients with inflammatory conditions. We examined peripheral blood mononuclear cells (PBMC) from rheumatoid arthritis patients with active inflammation and from healthy controls, and found that CD4(+) T cells contained an equal proportion of CD25(+)CD127(-)/low cells in both groups. In patients, not all these cells expressed intracellular FOXP3. Upon activation by anti-CD3/anti-CD28, PBMC rapidly down-regulated CD127, while FOXP3 up-regulation was transitory and occurred in fewer cells. The activated cells were not anergic to restimulation and had no suppressive effects. The distinct kinetics indicate that the FOXP3(-)CD127(-)/low cells in rheumatoid arthritis patients most likely represent activated non-regulatory T cells. This complicates the use of CD127 for identification of Tregs in inflammatory diseases.

Immunoglobulin E antibodies to rocuronium : a new diagnostic tool

Background: Diagnosis of allergy from neuromuscular blocking agents is not always straightforward. The objectives of the current study were to investigate the value of quantification of immunoglobulin E (IgE) by ImmunoCAP (Phadia AB, Uppsala, Sweden) in the diagnosis of rocuronium allergy and to study whether IgE inhibition tests can predict clinical cross-reactivity between neuromuscular blocking agents. Methods: Twenty-five rocuronium-allergic patients and 30 control individuals exposed to rocuronium during uneventful anesthesia were included. Thirty-two sera (total IgE > 1,500 kU/l) were analyzed for potential interference of elevated total IgE titers. Results were compared with quantification of IgE for suxamethonium, morphine, and pholcodine. Cross-reactivity between drugs was assessed by IgE inhibition and skin tests. Results: Sensitivity of IgE for rocuronium, suxamethonium, morphine, and pholcodine was 68, 60, 88, and 86%, respectively. Specificity was 100% for suxamethonium, morphine, and pholcodine IgE and 93% for rocuronium IgE. ROC analysis between patients and control individuals changed the threshold to 0.13 kUa/l for rocuronium, 0.11 kUa/l for suxamethonium, 0.36 kUa/l for morphine, and 0.43 kUa/l for pholcodine. Corresponding sensitivity was 92, 72, 88, and 86%, respectively. Specificity was unaltered. Interference of elevated total IgE with quantification of IgE was demonstrated by the analysis in sera with a total IgE greater than 1,500 kU/l. IgE inhibition did not predict clinical relevant cross-reactivity. Conclusions: The rocuronium ImmunoCAP constitutes a reliable technique to diagnose rocuronium allergy, provided an assay-specific decision threshold is applied. IgE assays based on compounds bearing ammonium epitopes are confirmed to represent reliable tools to diagnose rocuronium allergy. High total IgE titers were observed to affect specificity of the assays.