Blocking KV1.3 channels inhibits Th2 lymphocyte function and treats a rat model of asthma.

Allergic asthma is a chronic inflammatory disease of the airways. Of the different lower airway-infiltrating immune cells that participate in asthma, T lymphocytes that produce Th2 cytokines play important roles in pathogenesis. These T cells are mainly fully differentiated CCR7(-) effector memory T (TEM) cells. Targeting TEM cells without affecting CCR7(+) naïve and central memory (TCM) cells has the potential of treating TEM-mediated diseases, such as asthma, without inducing generalized immunosuppression. The voltage-gated KV1.3 potassium channel is a target for preferential inhibition of TEM cells. Here, we investigated the effects of ShK-186, a selective KV1.3 channel blocker, for the treatment of asthma. A significant proportion of T lymphocytes in the lower airways of subjects with asthma expressed high levels of KV1.3 channels. ShK-186 inhibited the allergen-induced activation of peripheral blood T cells from those subjects. Immunization of F344 rats against ovalbumin followed by intranasal challenges with ovalbumin induced airway hyper-reactivity, which was reduced by the administration of ShK-186. ShK-186 also reduced total immune infiltrates in the bronchoalveolar lavage and number of infiltrating lymphocytes, eosinophils, and neutrophils assessed by differential counts. Rats with the ovalbumin-induced model of asthma had elevated levels of the Th2 cytokines IL-4, IL-5, and IL-13 measured by ELISA in their bronchoalveolar lavage fluids. ShK-186 administration reduced levels of IL-4 and IL-5 and induced an increase in the production of IL-10. Finally, ShK-186 inhibited the proliferation of lung-infiltrating ovalbumin-specific T cells. Our results suggest that KV1.3 channels represent effective targets for the treatment of allergic asthma.

Imipridones inhibit tumor growth and improve survival in an orthotopic liver metastasis mouse model of human uveal melanoma.

Purpose: Uveal melanoma (UM) is a highly aggressive disease with very few treatment options. We previously demonstrated that mUM is characterized by high oxidative phosphorylation (OXPHOS). Here we tested the anti-tumor, signaling and metabolic effects of imipridones, CLPP activators which reduce OXPHOS indirectly and have demonstrated safety in patients. Experimental Design: We assessed CLPP expression in UM patient samples. We tested the effects of imipridones (ONC201, ONC212) on the growth, survival, signaling and metabolism of UM cell lines in vitro, and for therapeutic effects in vivo in UM liver metastasis models. Results: CLPP expression was confirmed in primary and mUM patient samples. ONC201/212 treatment of UM cell lines in vitro decreased OXPHOS effectors, inhibited cell growth and migration, and induced apoptosis. ONC212 increased metabolic stress and apoptotic pathways, inhibited amino acid metabolism, and induced cell death-related lipids. ONC212 also decreased tumor burden and increased survival in vivo in two UM liver metastasis models. Conclusion: Imipridones are a promising strategy for further testing and development in mUM.

Skin testing for Beta-lactam antibiotics: impact of the availability of a major determinant.

Beta-lactam antibiotics are very effective agents for a variety of infections. In patients with beta-lactam allergy, these drugs are withheld due to fear of subsequent allergic reactions. Therefore, increasing their exposure to broad spectrum antibiotics, which are more costly, have greater side effects, and increase the risk of developing resistant organisms. Up to 90 % of patients with a proposed beta-lactam sensitivity can tolerate beta lactam agents after appropriate evaluation. Skin testing to beta-lactam agents is the gold standard in evaluating patients with type I, immediate hypersensitivity reactions. The robust negative predictive value of this test has yet to be surpassed by any other testing modality currently available.

Targeting IRS-1/2 in Uveal Melanoma Inhibits In Vitro Cell Growth, Survival and Migration, and In Vivo Tumor Growth.

Uveal melanoma originating in the eye and metastasizing to the liver is associated with poor prognosis and has only one approved therapeutic option. We hypothesized that liver-borne growth factors may contribute to UM growth. Therefore, we investigated the role of IGF-1/IGF-1R signaling in UM. Here, we found that IRS-1, the insulin receptor substrate, is overexpressed in both UM cells and tumors. Since we previously observed that IGF-1R antibody therapy was not clinically effective in UM, we investigated the potential of NT157, a small molecule inhibitor of IRS-1/2, in blocking this pathway in UM. NT157 treatment of multiple UM cell lines resulted in reduced cell growth and migration and increased apoptosis. This treatment also significantly inhibited UM tumor growth in vivo, in the chicken egg chorioallantoic membrane (CAM) and subcutaneous mouse models, validating the in vitro effect. Mechanistically, through reverse phase protein array (RPPA), we identified significant proteomic changes in the PI3K/AKT pathway, a downstream mediator of IGF-1 signaling, with NT157 treatment. Together, these results suggest that NT157 inhibits cell growth, survival, and migration in vitro, and tumor growth in vivo via inhibiting IGF-1 signaling in UM.

Efficacy of Oral Tranexamic Acid Versus Combined Oral Contraceptives for Heavy Menstrual Bleeding.

Introduction Heavy menstrual bleeding (HMB) is characterized by high blood loss (>80 mL per cycle) at regular menstrual intervals. It can have an impact on a woman's bodily, mental, and/or material well-being. The etiology is varied and can be local, systemic, or iatrogenic. The occurrence of HMB is between 4% and 27%, depending on objective menstrual bleeding measurements and on high estimates based on subjective bleeding measures. This study was conducted to assess the efficacy of oral tranexamic acid versus combined oral contraceptive (COC) pills in the management of excessive menstrual bleeding. Methodology A comparative study was conducted at the Obstetrics and Gynecology Department of Combined Military Hospital Peshawar, Pakistan, from October 2020 to March 2021. Women aged above 18 years who presented with heavy menstrual bleeding (HMB) were included in the study. The exclusion criteria included all women with contraindications to the use of tranexamic acid, such as lactating mothers, pregnancy, use of oral contraceptives or steroids, history of renal malfunction or stroke, family history of thromboembolic disease, and ovarian or endometrial carcinoma. Patients with diagnosed leiomyomas with a size between >1 and 10 cm were included in the study. Women were allocated randomly into group A who received oral tranexamic acid 3.9-4 g per day or group B who received oral COC pills containing a combination of ethinyl estradiol 30 µg and norgestrel 0.3 mg. The efficacy of treatment was considered successful if there was a mean reduction in menstrual blood loss that was significantly greater than the baseline values. Results There were 178 patients in total, with 89 patients in each group. It was found that both oral tranexamic acid and combined oral contraceptives were equally effective in reducing the mean blood loss among patients and there was no statistical difference observed between the two groups. Upon stratification, it was found that both treatment groups were highly effective in younger age groups. Similarly, there was no significant difference in efficacy with respect to diabetes mellitus or hypertension. However, in individuals with leiomyomas, efficacy was significantly higher in patients who were in group B (combined oral contraceptives) (p = 0.004), and 46.1% of women in group A and 60.6% of women in group B did not experience any discomfort. Conclusion The current study revealed that both oral tranexamic acid and COC pills were equally effective in reducing the mean blood loss among patients with HMB. It was further found that the efficacy of both therapies was significantly higher in younger age groups. The efficacy of therapy was significantly reduced with the increasing age of the patient. Moreover, it was found that patients with leiomyomas benefitted more significantly from COC pills. There were no severe adverse effects reported in the study. However, future researches can explore the long-term side effects of both therapies. In short, both therapies were comparable in terms of efficacy and safety. Heavy menstrual bleeding can negatively impact a woman, emotionally and physically. Therefore, it is encouraged that physicians use their expert judgment while prescribing either oral tranexamic acid or COC pills to patients with HMB.

Preferential uptake of antioxidant carbon nanoparticles by T lymphocytes for immunomodulation.

Autoimmune diseases mediated by a type of white blood cell-T lymphocytes-are currently treated using mainly broad-spectrum immunosuppressants that can lead to adverse side effects. Antioxidants represent an alternative approach for therapy of autoimmune disorders; however, dietary antioxidants are insufficient to play this role. Antioxidant carbon nanoparticles scavenge reactive oxygen species (ROS) with higher efficacy than dietary and endogenous antioxidants. Furthermore, the affinity of carbon nanoparticles for specific cell types represents an emerging tactic for cell-targeted therapy. Here, we report that nontoxic poly(ethylene glycol)-functionalized hydrophilic carbon clusters (PEG-HCCs), known scavengers of the ROS superoxide (O2•-) and hydroxyl radical, are preferentially internalized by T lymphocytes over other splenic immune cells. We use this selectivity to inhibit T cell activation without affecting major functions of macrophages, antigen-presenting cells that are crucial for T cell activation. We also demonstrate the in vivo effectiveness of PEG-HCCs in reducing T lymphocyte-mediated inflammation in delayed-type hypersensitivity and in experimental autoimmune encephalomyelitis, an animal model of multiple sclerosis. Our results suggest the preferential targeting of PEG-HCCs to T lymphocytes as a novel approach for T lymphocyte immunomodulation in autoimmune diseases without affecting other immune cells.

KCa1.1 inhibition attenuates fibroblast-like synoviocyte invasiveness and ameliorates disease in rat models of rheumatoid arthritis.

OBJECTIVE: Fibroblast-like synoviocytes (FLS) participate in joint inflammation and damage in rheumatoid arthritis (RA) and its animal models. The purpose of this study was to define the importance of KCa1.1 (BK, Maxi-K, Slo1, KCNMA1) channel expression and function in FLS and to establish these channels as potential new targets for RA therapy. METHODS: We compared KCa1.1 expression levels in FLS from rats with pristane-induced arthritis (PIA) and in FLS from healthy rats. We then used ex vivo functional assays combined with small interfering RNA-induced knockdown, overexpression, and functional modulation of KCa1.1 in PIA FLS. Finally, we determined the effectiveness of modulating KCa1.1 in 2 rat models of RA, moderate PIA and severe collagen-induced arthritis (CIA). RESULTS: We found that PIA FLS expressed the KCa1.1 channel as their major potassium channel, as has been found in FLS from patients with RA. In contrast, FLS from healthy rats expressed fewer of these channels. Inhibiting the function or expression of KCa1.1 ex vivo reduced proliferation and invasive properties of, as well as protease production by, PIA FLS, whereas opening native KCa1.1 or overexpressing the channel enhanced the invasiveness of both FLS from rats with PIA and FLS from healthy rats. Treatment with a KCa1.1 channel blocker at the onset of clinical signs stopped disease progression in the PIA and CIA models, reduced joint and bone damage, and inhibited FLS invasiveness and proliferation. CONCLUSION: Our results demonstrate a critical role of KCa1.1 channels in the regulation of FLS invasiveness and suggest that KCa1.1 channels represent potential therapeutic targets in RA.

Blocking KCa3.1 channels increases tumor cell killing by a subpopulation of human natural killer lymphocytes.

Natural killer (NK) cells are large granular lymphocytes that participate in both innate and adaptive immune responses against tumors and pathogens. They are also involved in other conditions, including organ rejection, graft-versus-host disease, recurrent spontaneous abortions, and autoimmune diseases such as multiple sclerosis. We demonstrate that human NK cells express the potassium channels Kv1.3 and KCa3.1. Expression of these channels does not vary with expression levels of maturation markers but varies between adherent and non-adherent NK cell subpopulations. Upon activation by mitogens or tumor cells, adherent NK (A-NK) cells preferentially up-regulate KCa3.1 and non-adherent (NA-NK) cells preferentially up-regulate Kv1.3. Consistent with this different phenotype, A-NK and NA-NK do not display the same sensitivity to the selective KCa3.1 blockers TRAM-34 and NS6180 and to the selective Kv1.3 blockers ShK-186 and PAP-1 in functional assays. Kv1.3 block inhibits the proliferation and degranulation of NA-NK cells with minimal effects on A-NK cells. In contrast, blocking KCa3.1 increases the degranulation and cytotoxicity of A-NK cells, but not of NA-NK cells. TRAM-34, however, does not affect their ability to form conjugates with target tumor cells, to migrate, or to express chemokine receptors. TRAM-34 and NS6180 also increase the proliferation of both A-NK and NA-NK cells. This results in a TRAM-34-induced increased ability of A-NK cells to reduce in vivo tumor growth. Taken together, our results suggest that targeting KCa3.1 on NK cells with selective blockers may be beneficial in cancer immunotherapy.

Insect anaphylaxis: where are we? The stinging facts 2012.

PURPOSE OF REVIEW: Insect allergy remains an important cause of morbidity and mortality in the United States. In 2011, the third iteration of the stinging insect hypersensitivity practice parameter was published, the first being published in 1999 and the second in 2004. Since the 2004 edition, our understanding of insect hypersensitivity has continued to expand and has been incorporated into the 2011 edition. This work will review the relevant changes in the management of insect hypersensitivity occurring since 2004 and present our current understanding of the insect hypersensitivity diagnosis and management. RECENT FINDINGS: Since the 2004 commissioning by the Joint Task Force (JTF) on Practice Parameters of 'Stinging insect hypersensitivity: a practice parameter update', there have been important contributions to our understanding of insect allergy. These contributions were incorporated into the 2011 iteration. Similar efforts were made by the European Allergy Asthma and Clinical Immunology Interest Group in 2005 and most recently in 2011 by the British Society of Allergy and Clinical Immunology. SUMMARY: Our understanding of insect allergy, including the natural history, epidemiology, diagnostic testing, and risk factors, has greatly expanded. This evolution of knowledge should provide improved long-term management of stinging insect hypersensitivity. This review will focus primarily on the changes between the 2004 and 2011 stinging insect practice parameter commissioned by the JTF on Practice Parameters, but will, where appropriate, highlight the differences between working groups.