Clinical immunology and immunopathology
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Clin. Immunol. Immunopathol. · Nov 1997
Complement activation in severe Plasmodium falciparum malaria.
We determined indices of plasma complement activation (C3, C4, Bb, C4d, iC3b, and SC5b-9), levels of tumor necrosis factor (TNF) and interleukin-6, and the APACHE II score in 23 patients with complicated Plasmodium falciparum malaria. On admission, plasma concentrations of Bb, SC5b-9, and C4d were markedly increased compared to healthy control subjects (n = 24) (4.5 +/- 1.9 vs 1.5 +/- 0.6 mg/L; 1125.7 +/- 496.9 vs 183.2 +/- 76.5 microg/L; and 15.7 +/- 5.7 vs 7.2 +/- 1.4 mg/L, P < 0.01 for all). In contrast C3 and iC3b concentrations were decreased (631.4 +/- 247 vs 947.3 +/- 243.2 and 105 +/- 17.9 vs 151.3 +/- 14.5 mg/L; P < 0.01 for both). ⋯ In addition, a significant correlation between C3 and iC3b (r = 0.689) and C4 and C4d (r = 0.737) existed. However, no relation between clinical disease severity and complement fragments existed. The results demonstrate that both the classical and the alternative pathways of the complement system are profoundly activated in complicated malaria.
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Clin. Immunol. Immunopathol. · Oct 1997
Circulating endotoxin and cytokines after cardiopulmonary bypass: differential correlation with duration of bypass and systemic inflammatory response/multiple organ dysfunction syndromes.
Cardiopulmonary bypass constitutes an injury that may cause postoperative pathophysiological changes due to systemic inflammatory response syndrome (SIRS) and multiple organ dysfunction syndrome (MODS). These complications include coagulopathy, hypotension, capillary leakage, and multiple organ injury. To investigate the role of endotoxin and cytokines in the response to bypass injury, we measured plasma levels of endotoxin and proinflammatory cytokines in 20 pediatric patients before and after bypass. ⋯ In contrast, TNF-alpha and IL-8 correlated with duration of bypass and were associated with SIRS/MODS. Certain clinical complications were associated with specific cytokines. Understanding the role of cytokinemia in SIRS/MODS may lead to better prognostic assessment and therapeutic modalities.
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Clin. Immunol. Immunopathol. · May 1997
The effects of general anesthesia on human peripheral immune cell distribution and cytokine production.
Anesthetic agents are believed to have an adverse effect on human immune defense mechanisms. We investigated changes in peripheral immune cell numbers such as natural killer (NK) cells, B cells, and T lymphocyte subpopulations (CD4+ and CD8+ cells) and differences in cytokine production after stimulation with different mitogens before and during narcosis. We studied 30 patients undergoing elective orthopedic surgery. ⋯ After the beginning of surgery, CD8-positive cells showed a return to control values and NK cell number increased slightly. These findings suggest that general anesthesia interferes with immune cell number and immune cell response. This may explain the clinically well-recognized disturbance of human immunity after surgery and general anesthesia.
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Clin. Immunol. Immunopathol. · May 1995
Quantitative differences in CD8+ lymphocytes, CD4/CD8 ratio, NK cells, and HLA-DR(+)-activated T cells of racially different male populations.
In an attempt to establish the reference ranges for lymphocyte subsets the distribution of lymphocyte-population-bearing surface markers such as CD3 (T cells), CD19 (B cells), CD4 (T helper/inducer cells), CD8 (T suppressor/cytotoxic cells), HLA-DR on CD3+ cells (activated T cells), and CD16 and/or CD56 on CD3- cells (NK cells) has been studied among normal male Saudi blood donors. Anticoagulated peripheral blood was stained with monoclonal antibodies and the lymphocytes were analyzed by flow cytometry for the expression of the above markers. ⋯ The most significant finding of the present study is the presence of a higher percentage and number of CD8+ T cells (P < 0.01) and a decreased CD4/CD8 ratio (P < 0.02) compared with the Caucasian controls. In addition, the Saudi male population has a significantly lower percentage and number of activated T cells (P < 0.05 and < 0.01, respectively) and a lower number of NK cells (P < 0.001).