Human leukocyte modulation

Ginseng extracts have also been shown to modulate the immune responsiveness of human leukocytes in vitro. For example, extracts from P. ginseng were reported to increase NK cell function and ADCC in PBMC from both healthy and immunocompromised individuals [18]. In addition, similar extracts and their degradation products displayed anti-complement activity [46]. In contrast to the mouse data described above, a standardized ginseng extract (Gerimax) by itself (no inflammatory stimulus) induced the production of IL-12 (but not IL-10) by PBMC from healthy test subjects [47],... 

Anti-hepatitis B virus activity in vitro and in vivo was also found in wogonin and baicalein (Fig. 4), the major active constituents of the traditional Chinese medicine Scutellaria radix.More recently, Blach-Olszewska et al investigated the effect of baicalein and wogonin on two important mechanisms of innate immunity The secretion of cytokines, and the natural resistance of human leukocytes to viral infection. The results obtained indicate that these fiavonoids modulate cytokine production, that is they inhibit interferons-a and -y, and stimulate tumor necrosis factor-a and interleukin production. They also augment the resistance of peripheral blood leukocytes to the vesicular stomatitis virus. 

Interferon-a. Alfa-interferon alpha-interferon IFN- LelF leukocyte interferon lymphoblastoid interferon. Family of highly homologous species -specific proteins that inhibits viral replication and cellular proliferation and modulates the immune response. One of the type I interferons. Produced by peripheral blood leukocytes or lymphoblastoid cells upon exposure to live or inactivated virus, double-stranded RNA. Or bacterial products. Multiple sub-types have been identified which contain 163-166 amino acids mol wt approximately 18.000-20,000 daltons. Production by virus stimulated human leukocytes I. Gresser, Proc. Soc. Exp. Biol Med. 108, 799 (1961). Purification C. 

Josaki, K., Contrino, J., Kristie, J., Krause, P., and Kreutzer, D. L. (1990). Pentoxifylline-induced modulation of human leukocyte function in vitro. Am. J. Pathol. 136,623-630. 

Since the basophil release reaction is one of the central steps in inflammatory reactions, we have also investigated the ability of exogenous adenosine to modulate IgE-mediated histamine release from human basophils. We have demonstrated that adenosine and its poorly metabolized derivative 2-chloroadenosine cause a dose-dependent inhibition of IgE-mediated histamine release from human basophils (15,16). Adenosine and 2-chloroadenosine appear to act on the cell surface of human basophils since 1) dipyridamole, which markedly inhibited H-adenosine uptake by human leukocytes, did not affect adenosine-induced inhibition of histamine secretion and 2) theophylline blocks the inhibition of release caused by the nucleoside. We have concluded that endogenous adenosine is probably one of the several autacoids that modulate the release reaction of human basophils. 

G. Marone, M. Valentine, and L.M. Lichtenstein, Modulation of cyclic AMP in human leukocytes by physiological doses of adenosine, Fed. Proc. 37 1688 (1978). 

Cassatella, M. A., Bazzoni, F., Calzetti, F., Guasparri, I., Rossi, F., Trinchieri, G. (1991). Interferon-/transcriptionally modulates the expression of the genes for the high affinity IgG-Fc receptor and the 47-kDa cytosolic component of NADPH oxidase in human polymorphonuclear leukocytes. J. Biol. Chem. 266, 22079-82. 

Petroni, K. C., Shen, L., Guyre, P. M. (1988). Modulation of human polymorphonuclear leukocyte IgG Fc receptors and Fc receptor-mediated functions by IFN-y and glucocorticoids. J. Immunol. 140, 3467-72. 

Koo, C., Lefkowitz, R.J., and Snyderman, R. (1983). Guanine nucleotides modulate the binding affinity of the oligopeptide chemoattractant receptor on human polymorphonuclear leukocytes. J. Clin. Invest. 72, 748-753. 

Multiple mechanisms are probably involved in immune-modulating effects of AMPs. A variety of receptors has been described for cathelicidins, however, only one biological function, that of LL-37-mediated chemotaxis of human peripheral blood leukocytes, is associated with a known receptor (formyl peptide receptor like 1), [187]. Human BD-2 recruits mast cells and LL-37 activates epithelial cells through at least 2 classes of receptors [183,202], LL-37 transactivates epidermal growth factor receptor (EGFR) and promotes the release of IL-ip [203], and LL-37-induced maturation of LPS-primed monocytes requires the P2X(7)... 

Schiffrin, E.J. et al., Immune modulation of blood leukocytes in humans by lactic acid bacteria criteria for strain selection, Am. J. Clin. Nutr., 66, 515S, 1997. 

Cell adhesion molecules (CAMs) are transmembrane glycoproteins that act at the cell surface to mediate specific binding interactions with other cell adhesion molecules on adjacent cells or with proteins in the extracellular matrix. They are responsible for the adhesion of various leukocytes with each other, with extracellular matrix and with other cell types. There are four families of CAMs that facilitate these interactions. The classification is based on differences in struchue and includes selectins, cadherins, integrins, and immunoglobulin superfamily (Table 9). CAMs play a role in renal morphogenesis and are expressed in the adult human kidney. These molecules can influence growth factor expression, and conversely growth factors can modulate production of cell surface adhesion molecules and the expression of extracellular matrix proteins. 

Schmidt, K.H., Steinhilber, D., Moser, U. and Roth, H.J. (1988) L-Ascorbic acid modulates 5-lipoxygenase activity in human polymorphonuclear leukocytes. Int. Arch. Allergy Appl. Immunol. 85 441-445. 

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