The y-linked autoimmune accelerating (yaa) locus is a potent autoimmune disease allele. Transcription profiling of yaa-bearing B cells revealed the overexpression of a cluster of X-linked genes that included Tlr7. FISH analysis demonstrated the translocation of this segment onto the yaa chromosome. The resulting overexpression of Tlr7 increased in vitro responses to Toll-like receptor (TLR) 7 signaling in all yaa-bearing males. B6.yaa mice are not overtly autoimmune, but the addition of Sle1, which contains the autoimmune-predisposing Slam͞Cd2 haplotype, causes the development of fatal lupus with numerous immunological aberrations. B6.Sle1yaa CD4 T cells develop the molecular signature for T FH cells and also show expression changes in numerous cytokines and chemokines. Disease development and all component autoimmune phenotypes were inhibited by Sles1, a potent suppressor locus. Sles1 had no effect on yaa-enhanced TLR7 signaling in vitro, and these data place Sles1 downstream from the lesion in innate immune responses mediated by TLR7, suggesting that Sles1 modulates the activation of adaptive immunity in response to innate immune signaling.Sle1 ͉ Sles1 ͉ Toll-like receptor 7 ͉ yaa

Susceptibility to autoimmunity in B6.Sle1b mice is associated with extensive polymorphisms between two divergent haplotypes of the SLAM/CD2 family of genes. The B6.Sle1b-derived SLAM/CD2 family haplotype is found in many other laboratory mouse strains but only causes autoimmunity in the context of the C57Bl/6 (B6) genome. Phenotypic analyses have revealed variations in the structure and expression of several members of the SLAM/CD2 family in T and B lymphocytes from B6.Sle1b mice. T lymphocytes from B6.Sle1b mice have modified signaling responses to stimulation at 4-6 weeks of age. While autoimmunity may be mediated by a combination of genes in the SLAM/CD2 family cluster, the strongest candidate is Ly108, a specific isoform of which is constitutively upregulated in B6.Sle1b lymphocytes.

Background Asthma has been considered an immunological disease mediated by Th2 cells and adaptive immunity. However, clinical and experimental observations suggest that additional pathways may regulate asthma, particularly in non-allergic forms of asthma, such as asthma associated with air pollution, stress, obesity and infection. Objectives Our goal was to understand Th2 cell-independent conditions which might lead to airway hyperreactivity (AHR), a cardinal feature of asthma. Methods We examined a mouse model of experimental asthma, in which AHR was induced with glycolipid antigens, which activate natural killer T (NKT) cells. Results In this model, AHR developed rapidly when mice were treated with NKT cell-activating glycolipid antigens, even in the absence of conventional CD4+ T cells. The activated NKT cells directly induced alveolar macrophages to produce IL-33, which in turn activated NKT cells as well as natural helper cells, a newly described non-T, non-B, innate lymphoid cell type, to increase production of IL-13. Surprisingly, this glycolipid-induced AHR pathway required not only IL-13, but also IL-33 and its receptor, ST2, since it was blocked by an anti-ST2 mAb, and was greatly reduced in ST2−/− mice. When adoptively transferred into IL-13−/− mice, both wildtype natural helper cells and NKT cells were sufficient for the development of glycolipid induced AHR. Conclusion Since plant pollens, house dust and some bacteria contain glycolipids that can directly activate NKT cells, these studies suggest that AHR and asthma can fully develop, or be greatly enhanced, through innate immune mechanisms, involving IL-33, natural helper cells and NKT cells.

The HDAC inhibitors are a new family of antineoplastic agents. Since the entry of these agents into our therapeutic armamentarium, there has been increasing interest in their use. Although this family comprises chemical compounds from unrelated chemical classes that have different HDAC isoform specificities, they surprisingly have very similar toxicity profiles. In contrast, the observed toxicity profile is somewhat different from that of traditional cytotoxic chemotherapeutic agents and from other epigenetic agents. While some of the side effects may be familiar to the oncologist, others are less commonly seen. As some patients remain on therapy for a prolonged period of time, the long-term sequelae need to be characterized. In addition, since preclinical models suggest promising activity when used in combination with other antineoplastic agents, combination trials are being pursued. It will thus be important to distinguish the relative toxicity attributed to these agents and be alert to the exacerbation of toxicities observed in single agent studies. Notably, few of the agents in this class have completed phase 2 testing. Consequently, more clinical experience is needed to determine the relative frequency of the observed side effects, and to identify and develop approaches to mitigate potential clinical sequelae.

Among various surface molecules screened, CXCR4 was significantly up-regulated on monocytes, neutrophils, B cell subsets, and plasma cells in multiple murine models of lupus with active nephritis, including B6.Sle1Yaa, BXSB, and MRL.lpr. TLR-mediated signaling and inflammatory cytokines accounted in part for this increase. Increased CXCR4 expression was associated with functional consequences, including increased migration and enhanced B cell survival. Simultaneously, the ligand for CXCR4, CXCL12, was significantly up-regulated in the nephritic kidneys. Treatment with a peptide antagonist of CXCR4 prolonged survival and reduced serum autoantibodies, splenomegaly, intrarenal leukocyte trafficking, and end organ disease in a murine model of lupus. These findings underscore the pathogenic role of CXCR4/CXCL12 in lymphoproliferative lupus and lupus nephritis and highlight this axis as a promising therapeutic target in this disease.

Natural phytochemicals and their derivatives are good drug candidates for anticancer therapeutic approaches against multiple targets. We report here the initial findings from our studies on the anticancer properties of the leaves of the medicinal plant Sesbania grandiflora. In the current study, five different solvent fractions from the leaves of S. grandiflora were tested on cancer cell lines such as MCF-7, HepG2, Hep-2, HCT-15, and A549. The methanolic fraction of S. grandiflora was found to exert potent antiproliferative effects especially in the human lung cancer cell line, A549. Caspase 3 was activated in the methanolic fraction treated A549 cells thereby leading to cell death by apoptosis. DAPI staining, DNA laddering, and decrease in mitochondrial membrane potential further confirmed the apoptotic mode of cell death. The high levels of ROS intermediates as evidenced by DCF-DA staining could have played a role in the apoptotic induction. Decrease in levels of cyclin D1 and decrease in the activation of NFkB were observed in A549 cells on treatment with methanolic fraction, giving a hint on the possible mechanism of action. These results prove that the medicinal plant S. grandiflora can be explored further for promising candidate molecules to combat cancer, especially lung cancer.

Recent advances in modern technology have led to the understanding that not all genetic information is coded into protein and that the genomes of each and every organism including insects produce non-coding RNAs that can control different biological processes. Among RNAs identified in the last decade, long non-coding RNAs (lncRNAs) represent a repertoire of a hidden layer of internal signals that can regulate gene expression in physiological, pathological, and immunological processes. Evidence shows the importance of lncRNAs in the regulation of host–pathogen interactions. In this review, an attempt has been made to view the role of lncRNAs regulating immune responses in insects.

Genetic analyses of the lupus-prone NZM2410 mouse have identified multiple susceptibility loci on chromosome 7, termed Sle3 and Sle5. Both of these loci were contained within a large congenic interval, originally termed as Sle3 that strongly impacts a variety of myeloid and T-cell phenotypes and mediates fatal lupus nephritis when combined with Sle1. We have now produced two subcongenic strains, B6.Sle3 and B6.Sle5, carrying the Sle3 and Sle5 intervals separately and characterized their phenotypes as monocongenic strains and individually in combination with Sle1. Neither B6.Sle3 nor B6.Sle5 monocongenic strain develop severe autoimmunity; however, both of these intervals cause the development of severe glomerulonephritis when combined with Sle1. Thus, B6.Sle1Sle3 and B6.Sle1Sle5 exhibit splenomegaly, expansion of activated B and CD4 þ T-cell populations and high levels of IgG and IgM autoantibodies targeting multiple nuclear antigens, intact glomeruli and various other autoantigens. In addition, B6.Sle1Sle3 mice also produced higher levels of IgA antinuclear autoantibodies, which were implicated in the development of IgA nephropathy. Our results indicate that Sle3 and Sle5 can independently complement with Sle1, through shared and unique mechanisms, to mediate the development of severe autoimmunity.