Joseph A. Bellanti

Cytokines and the Immune Response

The recent massive growth and development of clinical immunology has been enriched by the discovery of a new family of molecules, the cytokines, which consist of various groups of polypeptide mediators involved in the communication network of the cells of the immune system. This article provides an overview of the immune system and the current status of the cytokines and their clinical application.

Developmental immunology: clinical application to allergy-immunology

BACKGROUND An increase in prevalence of allergic diseases has been seen at an unprecedented rate in many countries throughout the world. Associated with this increase in allergic disease has been a disturbing increase in morbidity and mortality of such diseases as asthma despite the availability of several new therapeutic agents over the past 2 to 3 decades. The search for both environmental factors, eg, new allergens, as well as biologic markers of genetic susceptibility, eg, respiratory viruses, has yielded considerable promise for an explanation for this rising prevalence of allergic disease. OBJECTIVE To present a central unifying hypothesis based upon recent knowledge concerning the developing human immune system and its interaction with external environmental factors, particularly viral infections, as a basis for a clearer understanding of the changing faces of the allergic diseases throughout the lifespan of the individual. DATA SOURCES English language articles were selected from PubMed, as well as selected abstracts that would have immediate, practical clinical implications. RESULTS Review of the current literature strongly suggests a relationship between delayed acquisition of Th1 function in the allergy-prone infant, not only as a predictive marker of susceptibility to the development of allergic disease but also as an explanation for the unique vulnerability of these infants to viral infection, eg, bronchiolitis. Furthermore, viral infection during early development in the allergy-prone infant appears to facilitate allergic sensitization in early infancy. This interesting triad of immune deficiency, viral infection, and atopic genetic susceptibility may provide a basis for early detection of allergic disease and may offer new intervention strategies for the prevention of allergic and infectious disease in the young infant.

Abnormalities of Th1 function in non-IgE food allergy, celiac disease, and ileal lymphonodular hyperplasia: a new relationship?

BACKGROUND Non-IgE mechanisms may also be involved food allergy (FA). Our group has been studying the immunopathogenesis clinical entities in children with gastro-intestinal symptoms and in whom biopsies of the terminal ileum show lymphoid tissue masses referred to as ileal lymphonodular hyperplasia. Our more recent studies have demonstrated Th1/Th2 cytokine profiles associated with non-IgE FA and other clinical entities. OBJECTIVE We investigated 12 subjects with non-IgE FA (group 1) and 4 subjects with celiac disease (group 2). Cytokine profiles and immunologic studies of lymphocytes in peripheral blood and from gastro-intestinal biopsy tissues from patients in groups 1 and 2 were also evaluated. METHODS Group 1 consisted of 12 children with clinical symptoms of anorexia, diarrhea, and abdominal pain. The diagnosis of non-IgE FA was established by positive double-blind, placebo-controlled food challenge and reduced or negative immediate-type skin testing and negative IgE radioallergosorbent tests. Group 2 consisted of four patients with celiac disease and three adult females with biopsy-proven clinical symptoms of celiac disease. RESULTS In group 1, peripheral blood CD4 and CD8 lymphocyte distributions were normal, with a predominance of CD4+ cells with a decreased intracellular Th1 cytokine pattern and a normal Th2 intracellular cytokine pattern. In contrast, all four patients in group 2 not only displayed abnormal CD4 and CD8 peripheral blood lymphocyte distributions (CD8 > CD4), but also an abnormal predominance of CD4+ cells with an increased Th1 and a normal Th2 cytokine pattern. A similar abnormal pattern of CD4 > CD8 ratio was observed in intestinal biopsies. All 12 patients in group 1 showed lymphonodular hyperplasia in each of the biopsies and by ileoscopy. CONCLUSIONS These studies suggest that abnormalities in Th1 function may not only play a role in some patients with non--IgE-mediated FA in whom decreased Th1 function is seen, but also in patients with celiac disease in whom an increased Th1 function is seen. The studies also suggest that lymphonodular hyperplasia may be a hallmark histologic lesion in patients with non--IgE-mediated FA.

In vitro protective and enhancing effects of interferons from several species on human lymphotoxin-induced target cell killing

In a previous study it was reported that human alpha-interferons (IFN) caused a significant enhancement of human lymphotoxin (LT)-induced in vitro killing of human target cells. This synergistic effect was dose dependent and was demonstrable on normal and tumor cell targets. The effects of IFNs from human and several animal species on human LT-induced cell killing of human, mouse, and rabbit target cells are examined. In addition to enhancement of IFN, a new finding was made showing protective effects of IFN on human LT activity. IFN-induced enhancement or protection depended on the particular IFN:target cell combination, with the highest degree of enhancement being observed in the homologous human combination. In this latter case, IFN-induced enhancement was blocked by antiserum to IFN. While a role for other soluble factors cannot be ruled out, the results suggest that, in the homologous human system, enhancement of LT activity was mediated by IFN. These results are discussed in relationship to previously observed enhancing and protective effects of IFN in natural killer cell systems.

Gastrointestinal immunopathology and food allergy

OBJECTIVE To review the current data that support the pivotal function of the gastrointestinal immune system in health and disease and its critical role in the pathogenesis of a wide variety of clinical disorders associated with food allergy (FA). DATA SOURCES Internet-based literature search and our own data. STUDY SELECTION The studies included in this review were selected based on the expert opinion of the authors. RESULTS In contrast to the beneficial expressions of gastrointestinal-associated lymphoid tissue, which are seen with relevance to newer methods of delivery of vaccines directly applied to the gastrointestinal mucosal surfaces (eg, oral poliovirus, rotavirus, Salmonella typhi vaccines), the adverse consequences of a mucosal immune response gone astray are evidenced in many diseases such as FA. A classification of clinical disorders associated with FA based on classic mechanisms of immunologic injury is presented, which includes the following: (1) IgE-mediated, (2) non-IgE-mediated, and (3) mixed IgE- and non-IgE-mediated disorders. Our study of immunologic disturbance in patients with non-IgE FA revealed a pattern of increased CD4+ and decreased TH1 cell counts in peripheral blood mononuclear cells in contrast to patients with celiac disease, where a pattern of increased CD8+ and TH1 cell counts in peripheral blood mononuclear cells and increased CD8+ cell counts was seen. CONCLUSIONS The gastrointestinal immune response thus plays a pivotal role in maintaining protective immunity in health and a critical role in the pathogenesis of a wide variety of clinical disorders associated with FA.

Long Non-Coding RNA GAPLINC Promotes Tumor-Like Biologic Behaviors of Fibroblast-Like Synoviocytes as MicroRNA Sponging in Rheumatoid Arthritis Patients

Rapidly accumulating evidence has now suggested that the long non-coding RNAs (LncRNAs), a large and diverse class of non-coding transcribed RNA molecules with diverse functional roles and mechanisms, play a major role in the pathogenesis of many human inflammatory diseases. Although some LncRNAs are overexpressed in plasma, T cell, and synovial tissues of patients with rheumatoid arthritis (RA), there is a dearth of knowledge in what role these transcripts play in fibroblast-like synoviocytes (FLSs) of these patients. Here, our studies showed that GAPLINC, a newly identified functional LncRNA in oncology, displayed a greater degree of expression in FLSs from RA than in patients with traumatic injury. GAPLINC suppression in RA-FLS cells revealed significant alterations in cell proliferation, invasion, migration, and proinflammatory cytokines production. Additionally, we performed a preliminary bioinformatics analysis of GAPLINC gene sequence in order to find its target molecules, using miRanda, PITA, RNAhybrid algorithms, Kyoto encyclopedia of genes and genomes, and gene ontology analysis. Since the results predicted that some of microRNAs and mRNA may interact with GAPLINC, we simulated a gene co-action network model based on a competitive endogenous RNA theory. Further verification of this model demonstrated that silencing of GAPLINC increased miR-382-5p and miR-575 expression. The results of this study suggest that GAPLINC may function as a novel microRNAs sponging agent affecting the biological characteristics of RA-FLSs. Additionally, GAPLINC may also promote RA-FLS tumor-like behaviors in a miR-382-5p-dependent and miR-575-dependent manner. Based upon these findings, LncRNA GAPLINC may provide a novel valuable therapeutic target for RA patients.

In vitro induction of T regulatory cells by a methylated CpG DNA sequence in humans: Potential therapeutic applications in allergic and autoimmune diseases

BACKGROUND Allergic and autoimmune diseases comprise a group of inflammatory disorders caused by aberrant immune responses in which CD25+ Forkhead box P3-positive (FOXP3+) T regulatory (Treg) cells that normally suppress inflammatory events are often poorly functioning. This has stimulated an intensive investigative effort to find ways of increasing Tregs as a method of therapy for these conditions. One such line of investigation includes the study of how ligation of Toll-like receptors (TLRs) by CpG oligonucleotides (ODN) results in an immunostimulatory cascade that leads to induction of T-helper (Th) type 1 and Treg-type immune responses. OBJECTIVE The present study investigated the mechanisms by which calf thymus mammalian double-stranded DNA (CT-DNA) and a synthetic methylated DNA CpG ODN sequence suppress in vitro lymphoproliferative responses to antigens, mitogens, and alloantigens when measured by [3H]-thymidine incorporation and promote FoxP3 expression in human CD4+ T cells in the presence of transforming growth factor (TGF) beta and interleukin-2 (IL-2). METHODS Lymphoproliferative responses of peripheral blood mononuclear cells from four healthy subjects or nine subjects with systemic lupus erythematosus to CT-DNA or phytohemagglutinin (PHA) was measured by tritiated thymidine ([3H]-TdR) incorporation expressed as a stimulation index. Mechanisms of immunosuppressive effects of CT-DNA were evaluated by measurement of the degree of inhibition to lymphoproliferative responses to streptokinase-streptodornase, phytohemagglutinin (PHA), concanavalin A (Con A), pokeweed mitogen (PWM), or alloantigens by a Con A suppressor assay. The effects of CpG methylation on induction of FoxP3 expression in human T cells were measured by comparing inhibitory responses of synthetic methylated and nonmethylated 8-mer CpG ODN sequences by using cell sorting, in vitro stimulation, and suppressor assay. RESULTS Here, we showed that CT-DNA and a synthetic methylated DNA 8-mer sequence could suppress antigen-, mitogen-, and alloantigen-induced lymphoproliferation in vitro when measured by [3H]-thymidine. The synthetic methylated DNA CpG ODN but not an unmethylated CpG ODN sequence was shown to promote FoxP3 expression in human CD4+ T cells in the presence of TGF beta and IL-2. The induction of FoxP3+ suppressor cells is dose dependent and offers a potential clinical therapeutic application in allergic and autoimmune and inflammatory diseases. CONCLUSION The use of this methylated CpG ODN offers a broad clinical application as a novel therapeutic method for Treg induction and, because of its low cost and small size, should facilitate delivery via nasal, respiratory, gastrointestinal routes, and/or by injection, routes of administration important for vaccine delivery to target sites responsible for respiratory, gastrointestinal, and systemic forms of allergic and autoimmune disease.

The child’s immune system and pediatric tuberculosis

That children are more likely develop a severe form of TB is reflective of the differences in the maturational stages of their immune systems, but a paucity of data is available about how this system matures and what the relationship of these developmental immune deficiencies are with infection. Maturational deficiencies in the adaptive and innate immune systems in infants and young children may result in immature macrophage and DC function; Th1-type responses to pathogens; and a propensity to develop Th2-type CD4 T-cells in response to immunogens. In vitro responses of two groups of TST positive children at risk for TB were examined by comparing Enzyme-Linked ImmunoSorbent Assay (ELISA)-based IGRAs with clinical and TST findings. Age-related changes in the immune capacity for specific and mitogen-induced IFN-γ production was also examined in these two groups. In the original guidelines for the use of QFT-G, the US Centers for Disease Control and Prevention recommended that additional studies were needed, especially in children under five years of age, both to establish the validity of the assay as a diagnostic tool in the younger age group and to compare the accuracy of the test with the TST for diagnosing active and latent TB. Of TST positive US children, 10 of the 196 (5%) were found to be QFT-G positive; nine had an indeterminate response; of the 130 children from the Philippines who had been immunized with BCG, 115 were TST positive, and seven were also QFT-G positive. In BCG immunized children, all were TST positive and BCG-immunized and because of a presumptive diagnosis of TB, all had received anti-TB therapy; of the 30 children, 14 (47%) were found to be QFT-G-IT positive and one had an indeterminate response. For the study of variations in age-related immune capacity, the capacity of IFN-γ production was measured in various age groups of children in response to specific TB peptides (ESAT-6, CFP-10 and TB7.7) as well as to mitogen in amounts used in the QFT-G and the QFT-G-IT assay kits that had been provided. Both studies suggest that ELISA QFT-G and QFT-G-IT assays are useful for diagnosing TB in children and that adequate IFN-γ production was observed in all children in both groups following lymphocyte stimulation by either purified TB peptides or mitogen including those less than 5 years of age.

Lack of short-chain fatty acids and overgrowth of opportunistic pathogens define dysbiosis of neuromyelitis optica spectrum disorders: A Chinese pilot study

Background: Intestinal microbiota is an important environmental factor in the initiation and progression of autoimmune diseases. However, investigations on the gut microbiome in neuromyelitis optica spectrum disorders (NMOSD) are relatively insufficient, especially for that of the Asia population. Objectives: To evaluate whether or not the intestinal microbiota of NMOSD patients had specific microbial signatures. Methods: Next-generation sequencing and gas chromatography were employed to compare the fecal microbial composition and short-chain fatty acids (SCFAs) spectrum between patients with NMOSD (n = 84) and healthy controls (n = 54). Results: The gut microbial composition of NMOSD distinguished from healthy individuals. Streptococcus, significantly increased in NMOSD, is positively correlated with disease severities (p < 0.05). The use of immunosuppressants results in a decrease of Streptococcus, suggesting that Streptococcus might play a significant role in the pathogenesis of NMOSD. A striking depletion of fecal SCFAs was observed in NMOSD patients (p < 0.0001), with acetate and butyrate showing significantly negative correlation with disease severities (p < 0.05). Conclusion: The fecal organismal structures and SCFAs level of patients with NMOSD were distinctive from healthy individuals. These findings not only could be critical events driving the aberrant immune response responsible for the pathogenesis of these disorders but could also provide suggestions for disease therapy.

Tc17/IL-17A Up-Regulated the Expression of MMP-9 via NF-κB Pathway in Nasal Epithelial Cells of Patients With Chronic Rhinosinusitis

Chronic rhinosinusitis (CRS) is a common chronic inflammatory disease of the upper airways involving nasal cavity and sinus. Deriving both from its clinical complexity with protean clinical manifestations as well its pathogenetic heterogeneity, the molecular mechanisms contributing to the pathogenesis of CRS remain unclear, and attract a wide interest in the field. Current evidences indicate that IL-17A is highly expressed in chronic rhinosinusitis with nasal polyps (CRSwNP). However, its pathogenetic role in regulation of tissue remodeling of CRSwNP remains unknown. The present study aimed to investigate the cellular origins and functions of IL-17A cytokine in CRSwNP, and further determined whether IL-17A could affect the expression of metalloproteinases (MMPs), the remodeling factors of CRSwNP. The results showed that the expression of IL-17A was upregulated in nasal tissues of patients with CRSwNP compared to those with chronic rhinosinusitis without nasal polyps (CRSsNP) and controls. CD8+ cytotoxic T lymphocytes (Tc) were major IL-17A producers in nasal tissues of CRSwNP. Interleukin (IL)-17-producing CD8+ T cells (Tc17) was significantly higher in nasal tissues of CRSwNP than CRSsNP and controls. Nonetheless, no difference was observed among the IL-17A in peripheral blood lymphocytes of these three groups. Moreover, in the same patients, IL-17A expression was negligible in lymphocytes of peripheral blood when compared with nasal tissues. Increased gene and protein expression of MMP-7 and MMP-9 in patients with CRSwNP compared with controls were observed. In CRSwNP samples, IL-17A receptor (IL-17AR) co-localized with MMP-9 and they were mainly expressed in the epithelial cells. MMP-9 expression was up-regulated both in Primary human nasal epithelial cells (PHNECs) and a nasal epithelial cell line (RPMI 2650) by IL-17A treatment, and diminished by anti-IL-17AR treatment. Furthermore, IL-17A promoted the expression of MMP-9 by activating the NF-κB signal pathway. Thus, our results have revealed a crucial role of IL-17A and Tc cells on pathogenesis and tissue remodeling of CRSwNP.