lactoferrin and Acute-Phase-Reaction

Effects of soluble recombinant human type I interleukin-1 receptor (sIL-1RI) were evaluated in 18 volunteers given intravenous endotoxin and randomized to placebo (n = 6), low-dose (n = 6), or high-dose (n = 6) sIL-1RI. Soluble IL-1RI decreased IL-1 beta (P = .001), but decreased IL-1ra (P = .0001), and resulted in 10-fold and 43-fold dose-related increases in sIL-1RI-IL-1ra complexes compared with placebo (P < or = .001). High-dose sIL-1RI was associated with increased levels of immunoactive tumor necrosis factor-alpha (P = .02), IL-8 (P = .0001), and cell-associated IL-1 beta (P = .047). C-reactive protein levels were higher after sIL-1RI than placebo (P = .035). Soluble IL-1RI decreased the severity of chills (P = .03), but did not alter other symptoms, changes in temperature, systemic hemodynamic responses, or changes in leukocyte and platelet number. Thus, sIL-1RI had no discernable antiinflammatory effect following endotoxin administration due in part to low levels of circulating IL-1 beta and neutralization of IL-1ra inhibitory function. This latter interaction represents an indirect mechanism of agonist activity elicited by sIL-1RI and may contribute to increases in inflammatory mediators, limiting therapy with sIL-1RI during endotoxemia.

Topics: Acute-Phase Reaction; Adult; Blood Cell Count; Cytokines; Endotoxins; Female; Fever; Gene Expression Regulation; Hemodynamics; Humans; Immunologic Factors; Inflammation; Interleukin 1 Receptor Antagonist Protein; Interleukin-1; Lactoferrin; Male; Peptide Fragments; Receptors, Interleukin-1; Recombinant Fusion Proteins; Shivering; Sialoglycoproteins; Solubility; Tumor Necrosis Factor-alpha

The purpose of our study was to investigate changes in immunological parameters induced by weaning stress (including milk restriction) in calves. Fifteen Holstein calves were subjected to weaning at 6 weeks of age. Blood samples were collected at -14, -7, -2, 1, 3, and 5 days post-weaning (DPW; 0 DPW = 42 days). Weaning caused significant (p < 0.01) increases in the neutrophil (NE):lymphocyte (LY) ratio at 5 DPW with a significant (p < 0.05) reduction of LYs. The concentration of acute-phase proteins (haptoglobin and serum amyloid A) also increased significantly (p < 0.05) at 3 and 5 DPW compared to -2 DPW. Levels of the iron-binding protein lactoferrin decreased significantly (p < 0.05) after weaning. Serum tumor necrosis factor-α and cortisol levels were elevated (p < 0.05) at 3 DPW, while those of serum interferon-γ decreased (p < 0.05) at 1 and 3 DPW compared to levels observed before weaning. Weaning significantly (p < 0.05) decreased the percentage of CD25(+) T cells in the peripheral blood. In conclusion, weaning stress affected the NE:LY ratio along with the levels of acute phase proteins, lactoferrin, cortisol, and inflammatory cytokines in the peripheral blood of calves. Weaning stress may induce an acute phase response possibly through the elevation of cortisol production and modulation of inflammatory cytokines.

Topics: Acute-Phase Proteins; Acute-Phase Reaction; Animals; Cattle; Female; Flow Cytometry; Haptoglobins; Hydrocortisone; Interferon-gamma; Lactoferrin; Leukocyte Count; Leukocytes; Male; Serum Amyloid A Protein; Stress, Physiological; Tumor Necrosis Factor-alpha; Weaning

Lactoferrin (Ltf), an iron binding glycoprotein, is a pleiotropic molecule whose serum concentration increases under acute phase conditions. The physiological roles of this protein have been well elucidated, but the source and serum regulation of Ltf gene expression have not been investigated in detail as part of the acute phase reaction (APR). In the current work, the changes in hepatic Ltf-gene-expression during turpentine oil- (TO-) or LPS-induced APR were investigated. Ltf was upregulated at both the mRNA and protein levels in the liver of TO- and LPS-treated wild type (WT) mice. The pattern of induction however was different in both animal models indicating distinctive signalling patterns resulting in an acute phase reaction. Cytokines are the core regulators of APR. Among the major cytokines, IL-6 is an important signalling molecule, which also regulates iron homeostasis in response to an inflammatory situation. In this study, the administration of IL-6 induced Ltf gene expression in the liver of WT mice, in murine hepatocytes and in hepa 1-6 cells. Ltf-gene-expression was upregulated also in the liver of TO- and LPS-treated IL-6 knockout (KO) mice. The increase in serum Ltf after LPS injection was greater than after TO-injection both in WT and IL-6-KO mice. To evaluate the contribution of other acute phase cytokines in the regulation of Ltf-gene-expression in the liver, both in vitro and in vivo studies with IL-1β, TNF-α, or IFN-γ were performed. The results demonstrate that TNF-α and IFN-γ also upregulated Ltf-gene-expression, while IL-1β has no role in the regulation of Ltf-gene-expression.

Topics: Acute-Phase Reaction; Animals; Gene Expression; Hepatocytes; Interleukin-1beta; Interleukin-6; Lactoferrin; Liver; Mice; Mice, Knockout; RNA, Messenger; Tumor Necrosis Factor-alpha; Up-Regulation

The study was undertaken to search for additional diagnostic criteria allowing the depth of myocardial damage to be estimated in males aged 57.2 +/- 9.6 years. Few interrelated acute phase reaction indices, including the levels of interleukin-8 (IL-8), lactoferrin (LF), alpha2-macroglobulin (alpha2-MG), plasmin (PL) and alpha2-MG-PL circulating complexes, were studied in serum on days 1, 7, and 17 of the onset of the disease. In small-focal myocardial infarction, the levels of alpha2-MG and PL were decreased on day 1 and those of LF and IL-8 were increased on day 14. On the contrary, in large-focal myocardial infarction, the concentrations of IL-8 and LF rose just on day 1 while those of alpha2-MG and PL remained unchanged. The detected differences may be used as additional criteria in differential diagnosis, particularly when ECG was of no informative value. Further, the concurrent elevation of alpha2-MG, PL, and PL-alpha2MG concentrations in large-focal myocardial infarction is indicative of poor prognosis.

Topics: Acute-Phase Proteins; Acute-Phase Reaction; Aged; alpha-Macroglobulins; Electrocardiography; Humans; Interleukin-8; Lactoferrin; Male; Middle Aged; Myocardial Infarction

Serum amyloid A (SAA) is a 12-kDa protein secreted in large amounts by liver cells during microbial infections or inflammatory diseases. We have recently reported that SAA induces chemotaxis of polymorphonuclear cells (PMN), monocytes, and T lymphocytes and stimulates their adhesion to endothelial monolayers. In this study, we investigated whether SAA regulates PMN antimicrobial activities. We found that recombinant SAA (rSAA), at concentrations comparable to serum levels attained during an acute phase response, is a potent activator of PMN. Stimulation of PMN by rSAA results in a rapid and transient increase of cytosolic calcium concentration and up-regulation of cell-surface expression of antigens involved in adhesion and microbial recognition such as CD11c and CD16. In addition, stimulation of PMN with rSAA increases secretion of lactoferrin, an antimicrobial protein that is contained in specific granules of PMN and enhances PMN phagocytic activity against heat-killed Candida albicans. Finally, activation of PMN with rSAA enhances their anti-Candida activity within 30 min of stimulation. These results suggest that SAA is involved in up-regulating PMN antimicrobial activities and that high circulating concentrations of SAA as seen in the acute phase response may constitute a potential host defense mechanism against fungal infections.

Topics: Acute-Phase Reaction; Adult; Antigens, CD; Apolipoproteins; Calcium; Candida albicans; Cell Degranulation; Cells, Cultured; Dose-Response Relationship, Drug; Humans; Lactoferrin; N-Formylmethionine Leucyl-Phenylalanine; Neutrophil Activation; Neutrophils; Phagocytosis; Recombinant Proteins; Respiratory Burst; Serum Amyloid A Protein; Signal Transduction; Up-Regulation; Virulence Factors, Bordetella