Th1/Th2 cytokine profiles differentiating tuberculous from malignant pleural effusions: A systematic review and meta-analysis

Review question / Objective: To clarify which one has a different predominance of Th1 and Th2 immune responses in malignant and tuberculous pleural effusions. We did a meta-analysis of the results published previously to assess the levels of Th1/Th2 cytokines in two types of pleural effusion and evaluated its ability to distinguish TPE from MPE. Condition being studied: Malignant and tuberculous pleural effusions are the two most common types of exudative pleural effusions, both of which can be seen with the typical accumulation of lymphocytes. Immune responses mediated by either the Th1 or Th2 subset dominate, depending on different types of pleural effusion. Thus, we performed a meta-analysis of all available studies to quantitatively evaluate the levels of Th1/Th2 cytokine profiles in TPE and MPE, as well as to assess the potential diagnostic value of these cytokines in discriminating TPE from MPE.

Effect of occupational co-exposure to lead and cadmium on selected immunomodulatory cytokines

Occupational exposure to heavy metals like lead (Pb) and cadmium (Cd) is associated with the development of several diseases. The objective of this study was to determine the effect of occupational co-exposure to Pb and Cd on the blood levels of selected immune-modulatory cytokines related to T helper (Th), that is, Th1, interleukin-2 (IL-2), Th2, (IL-4 and IL-10), and Th17, (IL-17) cells. The study comprised 207 individuals divided into two groups: exposed ( n = 110) and nonexposed ( n = 97). Blood Pb and Cd were determined using Graphite Furnace Atomic Absorption Spectroscopy, and serum levels of cytokines were measured using enzyme-linked immunosorbent assay (ELISA). The study revealed significantly higher blood Pb and Cd levels in the exposed group. A significant decrease in Th1 cytokine-IL-2 and Th2 cytokine-IL-10 was found, while IL-4 (Th2 cytokine) and IL-17 (Th17) levels were higher in the exposed group. In the mixed exposure analysis, among all the selected cytokines, IL-4 levels were significantly different between individuals having higher levels of both Pb and Cd versus lower levels of Pb and Cd. While IL-2 levels were highest among the low Pb and Cd group, the IL-17 levels were highest among individuals with higher Cd levels. The study demonstrated that co-exposure to low levels of Pb and Cd might have an immune-modulatory effect. The data suggested a metal-induced pro-inflammatory immune response.

Altered cytokine profiles in relapsed paucibacillary leprosy: a case report

Background Individuals with relapses of leprosy should be monitored carefully, however, with respect to paucibacillary (PB) leprosy, it is sometimes difficult to make a definitive diagnosis of relapse, because the bacillary index is often negative. To evaluate the usefulness of cytokine profiling in a patient with relapsed PB leprosy who tested negative for anti-phenolic glycolipid-I antibodies, we analyzed the Mycobacterium leprae protein-induced cytokine expression in peripheral blood mononuclear cells of the patient. Case presentation An 89-year-old-male relapsed PB patient, first treated for leprosy over 50 years prior, was examined. In April 2012, he noticed three skin lesions consisting of annular erythema in the thighs. Slit skin smear tests were negative, and skin biopsies revealed a pathology of indeterminate-to-borderline tuberculoid leprosy. He received 600 mg of rifampicin once per month and 75 mg of dapsone daily for 12 months. The annular erythemas disappeared after starting treatment. Before treatment, and 6 and 12 months after starting treatment, the Th1/Th2 cytokine profiles in the supernatant of mononuclear cells from the patient before and after stimulation with Mycobacterium leprae soluble protein (MLS) were examined using a Cytometric Bead Array (CBA) Human Th1/Th2 Cytokine Kit II. The CBA Enhanced Sensitivity Flex Set system was applied to detect small amounts of cytokines in the serum just before treatment and one year before relapse. In the culture supernatant, just before treatment, increases in IFN-γ level and the IFN-γ/IL-10 ratio and a decreased IL-6 level were observed without stimulation. Upon stimulation with MLS, just before treatment, both the IFN-γ and TNF levels increased markedly, and twelve months after starting treatment, the IFN-γ and TNF levels decreased greatly. In the serum, just before treatment, increases in IFN-γ and TNF levels and the IFN-γ/IL-10 ratio were evident compared with those measured one year before relapse. Conclusions Cytokine profiling using culture supernatants and serum samples may be useful for the diagnosis of relapsed PB leprosy.

Nasal Administration of Lipopolysaccharide Exacerbates Allergic Rhinitis through Th2 Cytokine Production from Mast Cells

Background: Microbial infection or exposure to endotoxin later in life exacerbates established asthma. Mast cells are involved in the exacerbation of asthma. This exacerbation involves a toll-like receptor (TLR)–mediated response of mast cells. In the clinical practice of otolaryngology, otolaryngologists experience an exacerbation of nasal congestion when infectious rhinitis develops in patients with allergic rhinitis, but the mechanisms are unknown. Therefore, this study investigated the effect of lipopolysaccharide (LPS) on allergic rhinitis using a mouse allergic rhinitis model. Methods: Female BALB/c mice, TLR4 gene mutant C3H/HeJ mice or mast cell–deficient WBB6F1-W/Wv mice were sensitized intraperitoneally with ovalbumin (OVA)/alum, and were intranasal challenged with OVA and/or LPS. Nasal symptoms and histologic changes were examined. Cytokines in nasal tissue were examined by Western blot. The effects of LPS on degranulation and cytokine production of bone marrow–derived mast cells (BMMCs) were investigated. Results: Nasal administration of LPS together with the antigen exacerbated nasal symptoms, eosinophil infiltration of the nasal mucosa, and increased IL-5 production in the nasal mucosa. It was not observed in C3H/HeJ mice and WBB6F1-W/Wv mice. The addition of LPS increased the production of IL-5 from BMMCs in a dose-dependent manner, but no effect on degranulation was observed. Conclusions: Intranasal administration of LPS exacerbates allergic rhinitis through Th2 cytokine production from mast cells. This observation provides clues to the mechanism of exacerbation of allergic rhinitis caused by an infection in daily clinical practice.

A Preliminary Study on the Relationship between Parasitaemia and Cytokine Expression of Peripheral Blood Cells in Trypanosoma vivax-Experimentally Infected Cattle

Trypanosoma vivax outbreaks have been reported with increasing frequency worldwide, causing significant economic losses in livestock. Though several studies have suggested that cytokine responses may influence infection caused by Trypanosoma sp., their exact role remains unclear and may vary according to the animal species and parasite strain. The present study aimed to evaluate cytokine expression of peripheral blood cells from three Girolando dairy cows experimentally infected with T. vivax. For this purpose, blood samples were collected prior to the inoculation on the day of inoculation (D0), the day after inoculation (D1), and then every seven days up to 119 days after infection (DAI). Each animal presented a unique pattern of cytokine expression. While a tendency of a Th1 cytokine response was observed during the patent phase (presence of circulating parasites), an increase of Th2 cytokine expression was found at the beginning of the sub-patent phase (low parasitaemia or aparasitaemic periods). In animals that presented a better control of parasitaemia, IL-6 and IFNγ increased during most of the trial period. On the other hand, the cow that presented reduction of IL-1β, IL-2, and TNFα during the entire period did not control parasitaemia properly. A balance between the Th1 and Th2 profile is beneficial for parasite control and animal health. The results found in the present study are a first step towards elucidating the dynamics of cattle’s inflammatory response against T. vivax, requiring future studies focusing on the role of key cytokines on the controlling of parasitaemia in different stages of bovine trypanosomosis.

Significance of Interleukin (IL)-4 and IL-13 in Inflammatory Arthritis

Interleukin (IL)-4 and IL-13 belong to the T helper 2 (Th2) cytokine family, along with IL-3, IL-5, and IL-9. These cytokines are key mediators of allergic inflammation. They have important immunomodulatory activities and exert influence on a wide variety of immune cells, such as B cells, eosinophils, basophils, monocytes, fibroblasts, endothelial cells, airway epithelial cells, smooth muscle cells, and keratinocytes. Recent studies have implicated IL-4 and IL-13 in the development of various autoimmune diseases. Additionally, these cytokines have emerged as potential players in pathogenesis of inflammatory arthritis. Recent findings suggest that the IL-4 and IL-13 might play a significant role in the downregulation of inflammatory processes underlying RA pathology, and beneficially modulate the course of the disease. This review summarizes the biological features of the IL-4 and IL-13 and provides current knowledge regarding the role of these cytokines in inflammatory arthritis.

Interleukin-31 promotes fibrosis and T helper 2 polarization in systemic sclerosis

Systemic sclerosis (SSc) is a chronic multisystem disorder characterized by fibrosis and autoimmunity. Interleukin (IL)-31 has been implicated in fibrosis and T helper (Th) 2 immune responses, both of which are characteristics of SSc. The exact role of IL-31 in SSc pathogenesis is unclear. Here we show the overexpression of IL-31 and IL-31 receptor A (IL-31RA) in dermal fibroblasts (DFs) from SSc patients. We elucidate the dual role of IL-31 in SSc, where IL-31 directly promotes collagen production in DFs and indirectly enhances Th2 immune responses by increasing pro-Th2 cytokine expression in DFs. Furthermore, blockade of IL-31 with anti-IL-31RA antibody significantly ameliorates fibrosis and Th2 polarization in a mouse model of SSc. Therefore, in addition to defining IL-31 as a mediator of fibrosis and Th2 immune responses in SSc, our study provides a rationale for targeting the IL-31/IL-31RA axis in the treatment of SSc.

STAT1-Dependent Recruitment of Ly6ChiCCR2+ Inflammatory Monocytes and M2 Macrophages in a Helminth Infection

Signal Transducer and Activator of Transcription (STAT) 1 signaling is critical for IFN-γ-mediated immune responses and resistance to protozoan and viral infections. However, its role in immunoregulation during helminth parasitic infections is not fully understood. Here, we used STAT1−/− mice to investigate the role of this transcription factor during a helminth infection caused by the cestode Taenia crassiceps and show that STAT1 is a central molecule favoring susceptibility to this infection. STAT1−/− mice displayed lower parasite burdens at 8 weeks post-infection compared to STAT1+/+ mice. STAT1 mediated the recruitment of inflammatory monocytes and the development of alternatively activated macrophages (M2) at the site of infection. The absence of STAT1 prevented the recruitment of CD11b+Ly6ChiLy6G− monocytic cells and therefore their suppressive activity. This failure was associated with the defective expression of CCR2 on CD11b+Ly6ChiLy6G− cells. Importantly, CD11b+Ly6ChiLy6G− cells highly expressed PDL-1 and suppressed T-cell proliferation elicited by anti-CD3 stimulation. PDL-1+ cells were mostly absent in STAT1−/− mice. Furthermore, only STAT1+/+ mice developed M2 macrophages at 8 weeks post-infection, although macrophages from both T. crassiceps-infected STAT1+/+ and STAT1−/− mice responded to IL-4 in vitro, and both groups of mice were able to produce the Th2 cytokine IL-13. This suggests that CD11b+CCR2+Ly6ChiLy6G− cells give rise to M2 macrophages in this infection. In summary, a lack of STAT1 resulted in impaired recruitment of CD11b+CCR2+Ly6ChiLy6G− cells, failure to develop M2 macrophages, and increased resistance against T. crassiceps infection.

Helminth infection is associated with dampened cytokine responses to viral and bacterial stimulations in Tsimane hunter-horticulturalists

BackgroundSoil-transmitted helminth (STH) infections can catalyze immunological changes that affect the response to subsequent infections, particularly those that elicit strong inflammatory responses. As globalization heightens the risk that remote communities with high STH prevalence will encounter novel pathogens, understanding how STHs shape immune responses to these downstream infections becomes increasingly crucial.MethodologyWe worked with Tsimane forager-horticulturalists in the Bolivian Amazon, where STHs are prevalent. We tested whether STHs and eosinophil levels—most likely indicative of infection in this population—are associated with dampened immune responses to in vitro stimulation with H1N1 and lipopolysaccharide (LPS) antigens. Whole blood samples (n = 179) were treated with H1N1 vaccine and LPS and assayed for 13 cytokines (interferon gamma [INF-γ], interleukin [IL]-1β, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12p70, IL-13, Granulocyte-macrophage colony-stimulating factor [GM-CSF], and Tumor necrosis factor-alpha [TNF-α]). We evaluated how STHs and eosinophil levels affected cytokine responses and T helper (Th) 1 and Th2-cytokine suite responses to stimulation.ResultsInfection with Ascaris lumbricoides was significantly (p ≤ 0.05) associated with lower response of some cytokines to H1N1 and LPS in women. Eosinophils were significantly negatively associated with some cytokine responses to H1N1 and LPS, with the strongest effects in women, and associated with a reduced Th1- and Th2-cytokine response to H1N1 and LPS in women and men.Conclusions and implicationsWe find that STHs were associated with dampened cytokine responses to certain viral and bacterial antigens, and suggest that this mitigation of host-induced damage may reduce the incidence of cytokine storms in populations with high STH prevalence.