Influence of breast-feeding on the production of cytokines

PROBLEM: Recently, we reported increases in the production of interferon-gamma (IFN-gamma), interleukin-2 (IL-2), and IL-4 during the postpartum period. The present study was undertaken to investigate whether these increases might be explained by increased prolactin while breast-feeding. METHOD: Whole blood from 41 women who were breast-feeding, 13 women not breast-feeding, and 31 healthy non-pregnant women was stimulated with phorbol 12-myristate 13-acetate and ionomycin, and the levels of cytokines in the supernatant were measured by enzyme-linked immunosorbent assay. Their serum levels of prolactin were measured by enzyme immunoassay. RESULTS: Increases in IFN-gamma, IL-2, IL-4, and IL-10 production were observed in women who were breast-feeding but not in women who were not breast-feeding. Serum levels of prolactin correlated with the levels of IFN-gamma in culture supernatant. CONCLUSIONS: These results suggest that breast-feeding induces production of cytokines and that IFN-gamma production is enhanced by physiological concentrations of prolactin.     

IL-10 stimulates production of platelet-activating factor by monocytes of patients with active systemic lupus erythematosus (SLE)

IL-10 displays modulatory properties on the synthesis of platelet-activating factor (PAF), a potent inflammatory mediator of vascular injury. Despite the fact that IL-10 is considered to be an anti-inflammatory cytokine, IL-10 levels correlate with disease activity in SLE. Moreover, in SLE IL-10 is unable to exert its immunosuppressive and anti-inflammatory effects. We have investigated the ability of IL-10 to stimulate PAF production from monocytes of SLE patients. Spontaneous and IL-10-stimulated PAF production by peripheral blood monocytes was measured in active (n = 13) and inactive (n = 14) SLE patients and in 15 normal control subjects. We observed that monocytes derived from patients with active SLE, but not from controls or inactive SLE, spontaneously produced significant amounts of PAF. Moreover, IL-10 enhanced the synthesis of PAF from monocytes of active SLE patients only. IL-10-induced PAF production correlated with the severity of the disease and with the extent of proteinuria. These results indicate that IL-10 only stimulates the synthesis of PAF from monocytes of SLE patients when immunologically active, suggesting that IL-10 may possess a paradoxical proinflammatory effect in SLE by promoting the production of PAF, a secondary mediator of inflammation.     

Spontaneous secretion of interleukin-4, interleukin-10 and interferon-gamma by first trimester decidual mononuclear cells

PROBLEM: A T-helper cell type 2 (Th2) cytokine dominated microenvironment has been predicted to be crucial for successful pregnancy. However, little information is available about local cytokine secretion in the human decidua. We determined the spontaneous secretion of interleukin-4 (IL-4), interferon-gamma (IFN-gamma) and IL-10 by decidual mononuclear cells at the single cell level and compared it with their secretion by peripheral blood mononuclear cells (PBMC) in the first trimester of pregnancy. METHODS OF STUDY: The cytokine secretion from decidual and blood cells was detected by a sensitive enzyme-linked immunosorbent spot-forming cell (ELISPOT)-assay. RESULTS: Cells secreting IL-4 (median 153, range 8-530), IL-10 (median 188, range 32-1600) and IFN-gamma (median 123, range 15-1140) were detected in all decidual and blood samples. The cytokine secretion showed a co-linear pattern in both the blood and decidua, i.e. when one cytokine was secreted at high levels, the others followed the trend. No correlation was found between the number of cytokine secreting cells in blood and decidua for any of the cytokines. CONCLUSIONS: Interleukin-4 and IL-10 are locally secreted in the decidua early during normal pregnancy, probably counteracting the fetal rejecting effects of co-expressed IFN-gamma. The cytokine secretion by blood cells does not generally reflect the local secretion pattern during first trimester pregnancy.     

Molecular characterization and determination of the coding capacity of the genome of equine herpesvirus type 2 between the genome coordinates 0.235 and 0.258 (theEcoRI DNA fragment N; 4.2 kbp)

The complete DNA nucleotide sequence of theEcoRI DNA fragment N (0.235 to 0.258 viral map units) of equine herpes virus type 2 (EHV-2) strain T400/3 was determined. This DNA fragment comprises 4237 bp with a base composition of 55.23% G+C and 44.77% A+T. Nineteen open reading frames (ORFs) of 50-287 amino acid (aa) residues were detected. ORF number 10 is located between the nucleotide position 2220 and 2756 coding for a protein of 179 amino acid residues. This protein shows significant homology to the cytokine synthesis inhibitory factor (CSIF; interleukin 10) of human (76.4%) and mouse (68.5%), and to the Epstein-Barr virus (EBV) protein BCRF1 (70.6%). The existence of an interleukin 10 (IL-10) analogous gene within the genome of the EHV-2 was confirmed by screening the genome of nine EHV-2 strains using specific oligonucleotide primers corresponding to the 5 and 3 region of this particular gene by polymerase chain reaction. In all experiments an 870 bp DNA product was amplified. The specifity of the amplified DNA fragments obtained from individual EHV-2 strains was confirmed by DNA-DNA hybridization experiments. The DNA sequence analysis of the amplified DNA products of the EHV-2 strain LK was carried out. This analysis revealed the identity of the corresponding IL-10 gene (540 bp) of this strain to the IL-10 gene of EHV-2 strain T400/3. The presented data indicate that the EHV-2 genome harbors a viral interleukin 10-like gene. This is further evidence that the IL-10 gene can be present in the genomes of members of the Herpesviridae family.     

Psychosis as a predictor of response to lithium maintenance treatment in bipolar affective disorder

Sixty-six bipolar I lithium clinic patients were studied for a history of psychotic symptoms at some time during the course of their illness. Agreement between different sources of information was calculated, and the patient population was divided into psychotic and non-psychotic subgroups. Probability of remaining well on lithium for the different subgroups was analyzed by the life table method. Psychosis during mania appeared to be associated with especially good early lithium prophylaxis.     

Some studies on the mechanism of action of antibodies to nerve growth factor.

The effects of antibodies to the nerve growth factor from mouse salivary gland were examined in vitro and in vivo. Treatment of explants of receptive ganglia with antibody and complement did not produce cell damage as judged by the ability of the tissue to respond to nerve growth factor. New-born mice experimentally depleted of or genetically deficient in key complement components were susceptible to the action of the antiserum.These results show that the effect of the antibody is independent of complement and are consistent with the view that it acts by neutralization of endogenous nerve growth factor.     

The Epstein-Barr virus latent membrane protein 1 induces interleukin-10 in Burkitt's lymphoma cells but not in Hodgkin's cells involving the p38/SAPK2 pathway

Infection of B cells with Epstein-Barr Virus (EBV) induces interleukin-10 (IL-10) production, which may contribute to transformation. IL-10 can modulate the immune response at certain levels, playing a crucial role in balancing humoral and cellular responses. Moreover, it can function as a growth and differentiation factor for B cells. However, the mechanism of IL-10 induction is still unclear. Here we demonstrate that IL-10 was specifically induced by the EBV-latent membrane protein 1 (LMP1) in Burkitt's lymphoma (BL) cell lines BL2 and BL41. In two T cell lines (Jurkat, MOLT3), two NHL cell lines (U266, MHH-PREB1), or three Hodgkin's disease (HD) cell lines (L428, L540, and KMH2), LMP1 did not induce IL-10 expression. In contrast, LMP1 activated CD40 or CD54 (ICAM1) expression in the analyzed cell lines. LMP1 derivatives lacking the C-terminal activation regions (CTAR), by deletion of the amino acids between 187 and 351 (Delta CTAR1) or 232 and 386 (Delta CTAR2), alone, or together induced IL-10 at very low amounts compared to wild-type LMP1. Inhibition of LMP1-mediated NF kappa B activation by constitutive repressive I kappa B-alpha only marginally impaired IL-10 expression in BL2 cells, while SB2035080 at 5 microM (a specific p38/SAPK2 inhibitor) led to reduced IL-10 expression. Our findings confirm the role of LMP1 in transactivation of cellular genes possibly important for tumor immunoescape but show that more than one signaling pathway is involved in this activation and suggests the necessity of a defined conformation of CTARs to activate IL-10 involving p38/SAPK2.     

Variable regions of antibodies to synthetic polypeptides--I. Characterization of an idiotope expressed on antibodies and T-cell factors

Spleen cells from a Lewis rat immunized with affinity-purified B10 anti-(T,G)-A-L antibody were fused with the non-secreting murine hybridoma SP2/0. Cell lines secreting monoclonal antibodies specific for mu- and kappa-chains, as well as an idiotope on anti-(T,G)-A-L antibodies, were isolated and characterized. The anti-mu and -kappa antibodies, are true anti-isotypes, reacting with sera from all strains of mice tested. The anti-idiotope antibodies recognize a determinant on antibodies binding a GT-containing epitope. The proportion of anti-GAT antibody bearing the idiotope varies markedly in different murine strains. A 1000-fold higher level of antibody from Igha mice than from Ighb and Ighe mice is required to give an equivalent inhibition of the idiotope-anti-idiotope reaction. Analysis of monoclonal antibodies expressing the idiotope indicates that the affinity of binding between idiotope and anti-idiotope can vary by as much as two orders of magnitude. Immunoadsorbants prepared with anti-idiotope antibody bind suppressor factor secreted by a GAT-specific T-cell hybridoma.     

系统性红斑狼疮患者血清IL-10的水平及临床意义

目的 观察系统性红斑狼疮(systemic lupus erythematosus,SLE)患者血清IL-10的表达与疾病活动的关系.方法 选取22例SLE患者及24名健康人作为对照,根据狼疮疾病活动指数(SLE disease activity index,SLEDAI)将SLE患者分为活动期组和非活动期组,检测血清抗dsDNA抗体,血清总补体溶血活性(CH50)及C反应蛋白(C reactive protein,CRP),酶联免疫吸附法(ELISA)检测血清IL-10表达.结果 与对照组[(18.11±6.97)ng/L]相比,IL-10在SLE活动期组[(78.54±5.62)ng/L,P＜0.01]及非活动期组[(30.36±10.98)ng/L,P＜0.05]均有所增高,活动期组增高更为明显(与非活动期组相比,P＜0.05).IL-10水平与SLEDAI呈正相关(SLE活动期,r=0.77,P＜0.01;SLE非活动期,r=0.84,P＜0.01),IL-10的水平与抗dsDNA抗体(r=0.71,P＜0.01)、CRP(r=0.63,P＜0.01)和CH50(r=-0.56,P＜0.05)均相关.结论 IL-10在SLE患者血清中表达升高,在疾病活动时更为明显,IL-10能反应疾病活动的程度,可以做为临床观察SLE疾病活动的指标之一.