The attraction of leukocytes to tissues is essential for inflammation and the host response to infection. The process is controlled by chemokines, which are chemotactic cytokines. This review introduces the burgeoning family of cytokines, with special emphasis on their role in the pathophysiology of disease and their potential as targets for therapy. Structure and Function of Chemokines Over 40 chemokines have been identified to date, most of them in the past few years. The relations among chemokines were not initially appreciated, which led to an idiosyncratic nomenclature consisting of many acronyms. When initially identified, these proteins had no known biologic . . .

Chemokines — Chemotactic Cytokines That Mediate Inflammation

Proteins of moderate size having native peptide backbones are produced by a method of native chemical ligation. Native chemical ligation employs a chemoselective reaction of two unprotected peptide segments to produce a transient thioester-linked intermediate. The transient thioester-linked intermediate then spontaneously undergoes a rearrangement to provide the full length ligation product having a native peptide bond at the ligation site. Full length ligation products are chemically identical to proteins produced by cell free synthesis. Full length ligation products may be refolded and/or oxidized, as allowed, to form native disulfide-containing protein molecules. The technique of native chemical ligation is employable for chemically synthesizing full length proteins.

https://science.sciencemag.org/content/sci/266/5186/776.full.pdf

Synthesis of proteins by native chemical ligation

Background Although tumor-infiltrating T cells have been documented in ovarian carcinoma, a clear association with clinical outcome has not been established. Methods We performed immunohistochemical analysis of 186 frozen specimens from advanced-stage ovarian carcinomas to assess the distribution of tumor-infiltrating T cells and conducted outcome analyses. Molecular analyses were performed in some tumors by real-time polymerase chain reaction. Results CD3+ tumor-infiltrating T cells were detected within tumor-cell islets (intratumoral T cells) in 102 of the 186 tumors (54.8 percent); they were undetectable in 72 tumors (38.7 percent); the remaining 12 tumors (6.5 percent) could not be evaluated. There were significant differences in the distributions of progression-free survival and overall survival according to the presence or absence of intratumoral T cells (P<0.001 for both comparisons). The five-year overall survival rate was 38.0 percent among patients whose tumors contained T cells and 4.5 percent ...

http://inmunologia.umh.es/Doctorado/2003NEJMZhangintratumoralTcells%20Maciá.pdf

Intratumoral T cells, recurrence, and survival in epithelial ovarian cancer.

Over the past ten years, numerous chemokines have been identified as attractants of different types of blood leukocytes to sites of infection and inflammation. They are produced locally in the tissues and act on leukocytes through selective receptors. Chemokines are now known to also function as regulatory molecules in leukocyte maturation, traffic and homing of lymphocytes, and the development of lymphoid tissues.

Chemokines and leukocyte traffic

Publisher Summary This chapter focuses on interleukin-8 (IL-8) and related chemotactic cytokines—namely, CXC and CC chemokines. IL-8 is the best known member of a new class of cytokines that are widely studied because of their ability to attract and activate leukocytes, and their potential role as mediators of inflammation. IL-8 was originally isolated from the culture supernatants of stimulated human blood monocytes and was identified as a protein of 72 amino acids with a molecular weight of 8383. The three-dimensional structure of IL-8 has been studied by nuclear magnetic resonance spectroscopy and X-ray crystallography. In concentrated solution, and on crystallization, IL-8 is present as a dimer. The first CC chemokine was identified after cloning by differential hybridization from human tonsillar lymphocytes and was termed LD78. The CC and CXC chemokines are similar in size and have an overall structure that is characterized by the two intrachain disulfide bonds, short N-terminal and long C-terminal sequences. It discusses the role of chemokines in pathology with skin inflammation because psoriasis was the first disease to be linked to overproduction of IL-8. Several independent studies document the occurrence of high levels of IL-8 in the synovial fluid of inflamed joints of patients with different forms of rheumatic diseases, osteoarthritis, and gout.

Interleukin-8 and related chemotactic cytokines--CXC and CC chemokines.

A human receptor that is selective for the CXC chemokines IP10 and Mig was cloned and characterized. The receptor cDNA has an open reading frame of 1104-bp encoding a protein of 368 amino acids with a molecular mass of 40,659 dalton. The sequence includes seven putative transmembrane segments characteristic of G-protein coupled receptors. It shares 40.9 and 40.3% identical amino acids with the two IL-8 receptors, and 34.2-36.9% identity with the five known CC chemokine receptors. The IP10/Mig receptor is highly expressed in IL-2-activated T lymphocytes, but is not detectable in resting T lymphocytes. B lymphocytes, monocytes and granulocytes. It mediates Ca2+ mobilization and chemotaxis in response to IP10 and Mig, but does not recognize the CXC-chemokines IL-8, GRO alpha, NAP-2, GCP-2. ENA78, PF4, the CC-chemokines MCP-1, MCP-2, MCP-3, MCP-4, MIP-1 alpha, MIP-1 beta. RANTES, 1309, eotaxin, nor lymphotactin. The exclusive expression in activated T-lymphocytes is of high interest since the receptors for chemokines which have been shown so far to attract lymphocytes, e.g., MCP-1, MCP-2, MCP-3, MIP-1 alpha, MIP-1 beta, and RANTES, are also found in monocytes and granulocytes. The present observations suggest that the IP10/Mig receptor is involved in the selective recruitment of effector T cells.

https://rupress.org/jem/article-pdf/184/3/963/1108871/963.pdf

Chemokine receptor specific for IP10 and mig: structure, function, and expression in activated T-lymphocytes.

The responses of lymphocytes to six CC chemokines--MCP-1, MCP-2, MCP-3, MIP-1 alpha, MIP-1 beta, and RANTES--were studied using cloned human CD4+ and CD8+ T cells. All CC chemokines tested induced migration of both types of lymphocytes, whereas two CXC chemokines used as controls, IL-8 and IP-10, were inactive. The monocyte chemotactic proteins (MCP-1, MCP-2, and MCP-3) showed a typically bimodal concentration dependence, and were considerably more effective than MIP-1 alpha, MIP-1 beta, or RANTES. All CC chemokines also induced a rapid and transient rise in cytosolic free Ca2+ in either type of T cell. The rise was prevented by Bordetella pertussis toxin treatment, indicating that G-protein-coupled receptors are involved in signaling. It was most pronounced with MCP-1 and MCP-3, which is in agreement with the efficacy of these chemokines as chemoattractants. The responses to MCP-2, MIP-1 alpha, MIP-1 beta, and RANTES were weaker, and no changes were obtained on stimulation with IL-8 or IP-10. Freshly iso...

Monocyte chemotactic proteins MCP-1, MCP-2, and MCP-3 are major attractants for human CD4+ and CD8+ T lymphocytes.

Interleukin-8 (IL-8), a pro-inflammatory protein, has been shown by nuclear magnetic resonance (NMR) and x-ray techniques to exist as a homodimer. An IL-8 analog was chemically synthesized, with the amide nitrogen of leucine-25 methylated to selectivity block formation of hydrogen bonds between monomers and thereby prevent dimerization. This analog was shown to be a monomer, as assessed by analytical ultracentrifugation and NMR. Nevertheless, it was equivalent to IL-8 in assays of neutrophil activation, which indicates that the monomer is a functional form of IL-8.

https://science.sciencemag.org/content/sci/264/5155/90.full.pdf

Neutrophil activation by monomeric interleukin-8

Melanoma growth-stimulatory activity (MGSA), a peptide reported to be mitogenic for Hs294T human melanoma cells, has extensive sequence similarity to the neutrophil-activating peptide NAP-1/IL-8, suggesting functional similarities. To test this hypothesis, MGSA was chemically synthesized and tested for its effects on human neutrophils. It was found to induce chemotaxis, exocytosis of elastase, and changes in cytosolic-free calcium to an extent and at concentrations similar to NAP-1/IL-8. However, MGSA was considerably less potent than NAP-1/IL-8 in inducing the respiratory burst. Intradermal injections in rats of MGSA resulted in a massive accumulation of neutrophils. Our data demonstrate that, apart from its growth-stimulatory activity, MGSA is a potent inflammatory agonist with neutrophil-stimulating properties.

/pdf/neutrophil-activating-properties-of-the-melanoma-growth-5gkbkzplbc.pdf

Ian Clark-Lewis

Papers

Chemokine receptor specific for IP10 and mig: structure, function, and expression in activated T-lymphocytes.

Monocyte chemotactic proteins MCP-1, MCP-2, and MCP-3 are major attractants for human CD4+ and CD8+ T lymphocytes.

Neutrophil activation by monomeric interleukin-8

Neutrophil-activating properties of the melanoma growth-stimulatory activity.

The interleukin-8-related chemotactic cytokines GRO alpha, GRO beta, and GRO gamma activate human neutrophil and basophil leukocytes.