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As a fetal allograft to the mother, early conceptus regulates the intrauterine immune and systemic immune responses during early pregnancy in sheep. However, expression of T helper 1 (Th1) and Th2 cytokines in maternal lymph nodes is unclear during early pregnancy in sheep. In this study, inguinal lymph nodes were obtained on day 16 of the estrous cycle and on days 13, 16 and 25 of pregnancy (n = 4 for each group) in ewes, and qRT-PCR, western blot and immunohistochemistry were used to compare the expression of Th1 and Th2 cytokines in the lymph nodes. Our results showed that there were the highest levels of Th1 cytokines (IFN-γ, TNF-β and IL-2) and Th2 cytokines (IL-4, IL-5, IL-6 and IL-10) in the lymph nodes on day 13 or 16 of pregnancy. Furthermore, there were a downregulation of TNF-β and IL-2 and an upregulation of IL-5 and IL-10 on day 25 of pregnancy compared with that in nonpregnancy, with no significant difference in the expression of IFN-γ, IL-4, and IL-6 between the ewes on day 25 of pregnancy and nonpregnancy. The immunohistochemistry results showed that the IL-2 and IL-10 proteins were limited to the subcapsular sinus and trabeculae in the cortex, lymph sinus. In conclusion, early pregnancy exerted its effects on the lymph node and induced a Th2-biased response, which was essential for a normal pregnancy in sheep., (Copyright © 2019 Elsevier Inc. All rights reserved.)

The balance in the production and release of cytokines "Th1/Th2" or "Th17" or "regulatory T" is one of the key events in the pathogenesis of systemic sclerosis (SSc). Specifically, the Th2 cytokine response, characterized by the production of IL-4, IL-10 and TGF-β, leads to tissue fibrosis in patients with SSc. Many studies have shown the importance of analyzing the levels of cytokines as diagnostic or prognostic markers in the blood or in situ in patients with SSc. The restoration of the Th1/Th2/Th17/Treg balance will contribute to the effectiveness of treatment and the use of cytokine modulators may therefore be considered in developing new therapeutic approaches., (Copyright © 2010. Published by Elsevier SAS.)

Individual cytokines and groups of cytokines that might represent networks in chronic lymphocytic leukemia (CLL) were analyzed and their prognostic values determined. Serum levels of 23 cytokines were measured in 84 patients and 49 age-matched controls; 17 levels were significantly elevated in patients. Unsupervised hierarchical bicluster analysis identified 3 clusters (CLs) of highly correlated but differentially expressed cytokines: CL1 (CXCL9, CXCL10, CXCL11, CCL3, CCL4, CCL19, IL-5, IL-12, and IFNγ), CL2 (TNFα, IL-6, IL-8, and GM-CSF), and CL3 (IL-1β, IL-2, IL-4, IL-15, IL-17, and IFNα). Combination scores integrating expression of CL1/CL2 or CL1/CL3 strongly correlated (P < .005) with time-to-first-treatment and overall survival (OS), respectively. Patients with the worst course had high CL1 and low CL2 or CL3 levels. Multivariate analysis revealed that CL1/CL2 combination score and immunoglobulin heavy chain variable region mutation status were independent prognostic indicators for time-to-first-treatment, whereas CL1/CL3 combination score and immunoglobulin heavy chain variable region mutation status were independent markers for OS. Thus, we identified groups of cytokines differentially expressed in CLL that are independent prognostic indicators of aggressive disease and OS. These findings indicate the value of multicytokine analyses for prognosis and suggest therapeutic strategies in CLL aimed at reducing CL1 and increasing CL2/CL3 cytokines.

Host response to viral infection involves distinct effectors of innate and adaptive immunity, whose mobilization needs to be coordinated to ensure protection. Here we show that influenza virus triggers, in human blood dendritic-cell (DC) subsets (ie, plasmacytoid and myeloid DCs), a coordinated chemokine (CK) secretion program with 3 successive waves. The first one, occurring at early time points (2 to 4 hours), includes CKs potentially attracting effector cells such as neutrophils, cytotoxic T cells, and natural killer (NK) cells (CXCL16, CXCL1, CXCL2, and CXCL3). The second one occurs within 8 to 12 hours and includes CKs attracting effector memory T cells (CXCL8, CCL3, CCL4, CCL5, CXCL9, CXCL10, and CXCL11). The third wave, which occurs after 24 to 48 hours, when DCs have reached the lymphoid organs, includes CCL19, CCL22, and CXCL13, which attract naive T and B lymphocytes. Thus, human blood DC subsets carry a common program of CK production, which allows for a coordinated attraction of the different immune effectors in response to viral infection.

Neutrophil chemotaxis is a process that is essential for the recruitment of neutrophils to an inflamed site. In the present study, we found a remarkable increase in neutrophil chemotactic activity in the lysate of red blood cells (RBC) of mice infected with murine malaria, Plasmodium yoelii. A neutrophil chemotactic factor with an apparent molecular weight of 17 kDa (IP17) was isolated from RBC by a combination of anion-exchange chromatography on DE52 and cation-exchange chromatography on Mono S. A comprehensive GenBank database search of N-terminal amino acid sequences and MALDI-TOF mass analysis of IP17 revealed that IP17 is identical to a murine homologue of ISG15/UCRP, a member of the ubiquitin family of proteins that are inducible by interferon-beta. Recombinant mouse ISG15 showed neutrophil chemotactic activity comparable to that of natural IP17. IP17 showed specific chemotactic activity forward neutrophils and activated neutrophils to induce the release of eosinophil chemotactic factors. These results suggest that the ubiquitin family protein ISG15/UCRP has novel functions in neutrophil-mediated immune mechanisms.

Th2 responses, especially IL-10 secretion by circulating mononuclear cells are associated with the progressive form of AE and Th1 responses with resistance. The HLA B8, DR3, DQ2 haplotype is associated with the severity of AE in humans through immune-mediated mechanisms including an elevated production of Interleukin-10 (IL-10). Granulomatous infiltration of mononuclear cells around the parasitic vesicles is a hallmark of this disease; however, cytokine production by granuloma cells has never been studied. Tissue samples were taken in the periparasitic area and in the central area of the periparasitic granulomatous lesions from a patient with a progressive AE at surgery. Six pieces for each zone were incubated in culture medium with antibiotics and IL-2, together with irradiated autologous peripheral blood mononuclear cells as feeder cells. After four days the dead feeder cells were removed by density gradient centrifugation. Lymphocytes were stimulated with Echinococcus multilocularis vesicular fluid antigen (Emf) or PHA to study IL-10, IFN-, and IL-4 production in the supernatant. Emf-stimulated mononuclear cells from the central part of the lesions secreted more IL-10 and less IFN-gamma than cells from the periphery of the granuloma. At the basal level, IL-10 secretion by the locally infiltrating cells was also high and this confirms at the local granuloma level our previous results obtained from cultures of circulating mononuclear cells. The present study confirms that IL-10 secretion is a key feature of the immune response against E. multilocularis in humans. The location of the cells which produce the highest amount of IL-10, those in contact with parasitic structures, suggests that the parasite itself is able to modulate the immune response of the host so that the infiltrating cells cannot participate in the effector phase of the cellular immune response. The nature of the parasitic structures involved and the mechanisms which lead to an imbalanced cytokine production remain to be elucidated.

Different mechanisms underlie the phenomenon of peripheral tolerance. Recently, a new subset of CD4+ T cells, called T regulatory-1 (Tr1) cells, was described which show suppressor functions in vitro and in vivo and are characterized by a predominant production of IL-10 and/or TGF-beta. Tr1 cells have so far been generated experimentally in an IL-10-rich environment and hold promise for exploitation in the suppression of alloreactions and inflammatory or allergic dispositions. However, these cells have not been characterized in infectious diseases. Here we show that in the chronic helminth infection onchocerciasis (river blindness), where patients have relatively little sign of dermatitis despite the presence of millions of small worms in the skin, T cells can be obtained which bear characteristics of Tr1 cells, producing no IL-2 or IL-4 but substantial amounts of IL-10, variable amounts of IL-5, and some IFN-gamma. These cells display elevated amounts of CTLA-4 after stimulation and are able to inhibit other T cells in coculture, in contrast to Th1 and Th2 clones. This is the first time that this type of suppressor T cell has been cloned as naturally occurring during an infectious disease.

Proteins for which there are good structural, functional and genetic similarities that imply a common evolutionary origin, can have sequences whose similarities are low or undetectable by conventional sequence comparison procedures. Do these proteins have sequence conservation beyond the simple conservation of hydrophobic and hydrophilic character at specific sites and if they do what is its nature? To answer these questions we have analysed the structures and sequences of two superfamilies: the four-helical cytokines and cytochromes c'-b(562). Members of these superfamilies have sequence similarities that are either very low or not detectable. The cytokine superfamily has within it a long chain family and a short chain family. The sequences of known representative structures of the two families were aligned using structural information. From these alignments we identified the regions that conserve the same main-chain conformation: the common core (CC). For members of the same family, the CC comprises some 50% of the individual structures; for the combination of both families it is 30%. We added homologous sequences to the structural alignment. Analysis of the residues occurring at sites within the CCs showed that 30% have little or no conservation, whereas about 40% conserve the polar/neutral or hydrophobic/neutral character of their residues. The remaining 30% conserve hydrophobic residues with strong or medium limitations on their volume variations. Almost all of these residues are found at sites that form the "buried spine" of each helix (at sites i, i+3, i+7, i+10, etc., or i, i+4, i+7, i+11, etc.) and they pack together at the centre of each structure to give a pattern of residue-residue contacts that is almost absolutely conserved. These CC conserved hydrophobic residues form only 10-15% of all the residues in the individual structures.A similar analysis of the cytochromes c'-b(562), which bind haem and have a very different function to that of the cytokines, gave very similar results. Again some 30% of the CC residues have hydrophobic residues with strong or medium conservation. Most of these form the buried spine of each helix and play the same role as those in the cytokines. The others, and some spine residues bind the haem co-factor.

The flt3 ligand (FL) is a growth and differentiation factor for primitive hematopoietic precursors, dendritic cells, and natural killer cells. Human T lymphocytes express FL constitutively, but the cytokine is retained intracellularly within the Golgi complex. FL is mobilized from the cytoplasmic stores and its serum levels are massively increased during the period of bone marrow aplasia after stem cell transplantation (SCT). Signals that trigger the release of FL by T cells remain unknown. This study shows that interleukin (IL)-2, IL-4, IL-7, and IL-15, acting through a common receptor gamma chain (gammac), but not cytokines interacting with other receptor families, are efficient inducers of cell surface expression of membrane-bound FL (mFL) and secretion of soluble FL (sFL) by human peripheral blood T lymphocytes. The gammac-mediated signaling up-regulated FL in a T-cell receptor-independent manner. IL-2 and IL-7 stimulated both FL messenger RNA (mRNA) expression and translocation of FL protein to the cell surface. Cyclosporin A (CsA) inhibited gammac-mediated trafficking of FL at the level of transition from the Golgi to the trans-Golgi network. Accordingly, serum levels of sFL and expression of mFL by T cells of CsA-treated recipients of stem cell allografts were reduced approximately 2-fold (P <.01) compared to patients receiving autologous grafts. The conclusion is that FL expression is controlled by gammac receptor signaling and that CsA interferes with FL release by T cells. The link between gammac-dependent T-cell activation and FL expression might be important for T-cell effector functions in graft acceptance and antitumor immunity after SCT.

By differential hybridization of cDNA libraries from Fv-1 restrictive and non-restrictive somatic mutant mouse cells, we isolated a cDNA clone specifically present in the Fv-1 restrictive cells. Its sequence was found identical to that of heparin-binding growth-associated molecule or pleiotrophin (HB-GAM/PTN). We report here its genomic organization which has not been yet reported. Although the exon organization was similar to that of midkine, another member of the same family of heparin-binding factors, the sizes of introns were much larger and occupied more than a three-fold larger chromosomal region than midkine. As its introduction into Fv-1 non-restrictive cells failed to confer the Fv-1 restrictive character, HB-GAM/PTN is probably unrelated to Fv-1 restriction.