Factors regulating the differences in frequency of infiltration of Th17 and Treg of the blood-brain barrier

Controlling CD4+ immune cell infiltration of the brain is a leading aim in designing therapeutic strategies for a range of neuropathological disorders such as multiple sclerosis, Alzheimer's disease, and depression. CD4+ T cells are a highly heterogeneous and reprogrammable family, which includes various distinctive cell types such as Th17, Th1, and Treg cells. Interestingly Th17 and Treg cells share a related transcriptomic profile, where the TGFβ-SMADS pathway plays a fundamental role in regulating the differentiation of both of these cell types. However, Th17 could be highly pathogenic and was shown to promote inflammation in various neuropathological disorders. Conversely, Treg is anti-inflammatory and is known to inhibit Th17. It could be noticed that Th17 frequencies of infiltration of the blood-brain barrier in various neurological disorders are significantly upregulated. However, Treg infiltration numbers are significantly low. The reasons behind these contradicting observations are still unknown. In this perspective, we propose that the difference in the T-cell receptor repertoire diversity, diapedesis pathways, chemokine expression, and mechanical properties of these two cell types could be contributing to answering this intriguing question.

Adera2.0: A Drug Repurposing Workflow for Neuroimmunological Investigations Using Neural Networks

Drug repurposing in the context of neuroimmunological (NI) investigations is still in its primary stages. Drug repurposing is an important method that bypasses lengthy drug discovery procedures and focuses on discovering new usages for known medications. Neuroimmunological diseases, such as Alzheimer's, Parkinson's, multiple sclerosis, and depression, include various pathologies that result from the interaction between the central nervous system and the immune system. However, the repurposing of NI medications is hindered by the vast amount of information that needs mining. We previously presented Adera1.0, which was capable of text mining PubMed for answering query-based questions. However, Adera1.0 was not able to automatically identify chemical compounds within relevant sentences. To challenge the need for repurposing known medications for neuroimmunological diseases, we built a deep neural network named Adera2.0 to perform drug repurposing. The workflow uses three deep learning networks. The first network is an encoder and its main task is to embed text into matrices. The second network uses a mean squared error (MSE) loss function to predict answers in the form of embedded matrices. The third network, which constitutes the main novelty in our updated workflow, also uses a MSE loss function. Its main usage is to extract compound names from relevant sentences resulting from the previous network. To optimize the network function, we compared eight different designs. We found that a deep neural network consisting of an RNN neural network and a leaky ReLU could achieve 0.0001 loss and 67% sensitivity. Additionally, we validated Adera2.0's ability to predict NI drug usage against the DRUG Repurposing Hub database. These results establish the ability of Adera2.0 to repurpose drug candidates that can shorten the development of the drug cycle. The workflow could be download online.

Effect of Chemokine (C-C Motif) Ligand 7 (CCL7) and Its Receptor (CCR2) Expression on Colorectal Cancer Behaviors

Colorectal cancer is the source of one of the most common cancer-related deaths worldwide, where the main cause of patient mortality remains metastasis. The aim of this study was to determine the role of CCL7 (chemokine (C-C motif) ligand 7) in tumor progression and finding whether it could predict survival of colorectal cancer patients. Initially, our study focused on the crosstalk between mesenchymal stem cells (MSCs) and CT26 colon carcinoma cells and resulted in identifying CCL7 as a chemokine upregulated in CT26 colon cancer cells cocultured with MSCs, compared with CT26 in monoculture in vitro. Moreover, we showed that MSCs enhance CT26 tumor cell proliferation and migration. We analyzed the effect of CCL7 overexpression on tumor progression in a murine CT26 model, where cells overexpressing CCL7 accelerated the early phase of tumor growth and caused higher lung metastasis rates compared with control mice. Microarray analysis revealed that tumors overexpressing CCL7 had lower expression of immunoglobulins produced by B lymphocytes. Additionally, using Jh mutant mice, we confirmed that in the CT26 model, CCL7 has an immunoglobulin-, and thereby, B-cell-dependent effect on metastasis formation. Finally, higher expression of CCL7 receptor CCR2 (C-C chemokine receptor type 2) was associated with shorter overall survival of colorectal cancer patients. Altogether, we showed that CCL7 is essentially involved in the progression of colorectal cancer in a CT26 mouse model and that the expression of its receptor CCR2 could be related to a different outcome pattern of patients with colorectal carcinoma.

Delta-opioid receptor antagonism leads to excessive ethanol consumption in mice with enhanced activity of the endogenous opioid system

The opioid system modulates the central reinforcing effects of ethanol and participates in the etiology of addiction. However, the pharmacotherapy of ethanol dependence targeted on the opioid system is little effective and varies due to individual patients' sensitivity. In the present study, we used two mouse lines with high (HA) and low (LA) activity of the endogenous opioid system to analyze the effect of opioid receptor blockade on ethanol drinking behavior. We found that LA and HA lines characterized by divergent magnitudes of swim stress-induced analgesia also differ in ethanol intake and preference. Downregulation of the opioid system in LA mice was associated with increased ethanol consumption. Treatment with a non-selective opioid receptor antagonist (naloxone) had no effect on ethanol intake in this line. Surprisingly, in HA mice, the blockage of opioid receptors led to excessive ethanol consumption. Moreover, naloxone selectively induced high levels of anxiety- and depressive-like behaviors in HA mice which was attenuated by ethanol. With the use of specific opioid receptor antagonists we showed that the naloxone-induced increase in ethanol drinking in HA mice is mediated mainly by δ and to a lower extent by μ opioid receptors. The effect of δ-opioid receptor antagonism was abolished in HA mice carrying a C320T transition in the δ-opioid receptor gene (EU446125.1), which impairs this receptor's function. Our results indicate that high activity of the opioid system plays a protective role against ethanol dependence. Therefore, its blockage with opioid receptor antagonists may lead to a profound increase in ethanol consumption.

A comparative study of morphine stimulation and biphalin inhibition of human glioblastoma T98G cell proliferation in vitro

Biphalin is a new type of opioid peptide analog with high analgesic potency that is over 1000-fold greater than morphine. Because of its less addictive nature, biphalin has been suggested as a prospective new analgesic drug. Its high analgesic activity may be related to synergic interaction with all three types of opioid receptors (mu, delta, and kappa). Earlier data implicating involvement of opioid receptors, particularly MOR (mu opioid receptor) and KOR (kappa opioid receptor), in cell cycle regulation prompted us to investigate the effect of biphalin and morphine on human glioma T98G cell proliferation in vitro. We have documented an inhibitory effect of biphalin on tumor cell growth related to a decreased proliferation rate, decline of cell ability to form colonies, and modulation of the Ki-67 proliferation index. Morphine displayed the opposite effect and triggered stimulation of T98G cell proliferation. Our experiments have shown that biphalin might constitute an alternative solution for morphine application in anti-pain and anti-cancer therapy.

Chordoid meningiomas of a different histopathological pattern: a report of two cases

Chordoid meningioma is an uncommon histopathological variant of meningioma with a peculiar chordoma-like appearance. Its association with systemic inflammatory disorder linked to Castleman's syndrome was confirmed in the majority of young patients, however such a relationship in adults remains enigmatic. We report two cases of chordoid meningiomas in adult patients without manifestation of Castleman's syndrome. One tumour was almost totally composed of chordoma-like areas whereas the second one exhibited the unique combination of chordoma- and chondroma-like pattern. This is the first description of chordoid meningioma combined with extensive cartilaginous metaplasia. Both tumours exhibited histological evidence of infiltrative growth, accompanied by a relatively high proliferative index within structures of chordoid appearance. The designation of the chordoid component in meningioma is very important as this subtype of meningioma exhibits a more aggressive biological behaviour and higher risk of recurrence.

Pentoxifylline inhibits perforin-dependent natural cytotoxicity in vitro

Pentoxifylline (PTX) is commonly used in peripheral blood vessel diseases, however it has also been found to decrease the level of proinflammatory cytokines such as IL-12, TNF-alpha and IFN-gamma. Moreover, some authors reported that PTX suppresses spontaneous cytotoxicity of peripheral blood mononuclear cells (PBMC) in vitro. It could influence the mechanism of killing target cells by PBMC. For this reason we evaluated the influence of PTX on spontaneous cytotoxicity of PBMC against K562 and CaSki cell lines. Subsequently, we compared this effect to that evoked by dexamethasone, one of the most effective anti-inflammatory drugs. Our study revealed that PTX inhibits natural cytotoxicity preferentially through inhibition of perforin-mediated cell membrane damage, without a statistically significant influence on apoptosis induction. Furthermore, pentoxifylline inhibits natural cytotoxicity as effectively as dexamethasone. However, the result of PTX inhibitory influence is observed much earlier than that of dexamethasone. Currently PTX is commonly used in diseases that occur more frequently in elderly patients. We suggest that PTX, inhibiting perforin-dependent PBMC cytotoxic activity, could weaken anti-cancer action of immune system thus accelerating the progress of neoplasm formation in these patients.

Clinical aspects of disrupted Hedgehog signaling (Review)

The Hedgehog (HH) signaling pathway is involved in patterning and development of a variety of organ systems, including the nervous system, the skeletal system, the craniofacial structures, and the gastrointestinal tract. Recent evidence also implicates this signaling pathway in the postembryonic regulation of stem-cell number in epithelia and blood. The family of HH proteins consists of at least three different members, i.e., sonic HH (SHH), Indian HH (IHH), and desert HH (DHH). SHH is the most broadly expressed member of this family and is probably responsible for the major effects of this signaling pathway. The HH signal is received and transduced via a specific receptor complex composed of patched (PTCH) and smoothened (SMOH) transmembrane proteins. Abnormalities in this signaling cascade have been found in various developmental pathologies and neoplasms such as basal cell carcinoma. The abnormalities are associated with congenital or sporadic genetic alteration affecting function of different components of the HH signaling pathway, including SHH, PTCH, SMOH and GLI proteins.

Influence of culture medium pH on cytotoxicity of CD95L in vitro

CD95L belongs to the tumor necrosis factor-alpha (TNF-alpha) family, the members of which induce apoptosis by activation of their specific receptors. However, there are a few publications suggesting that two of these factors, TNF-alpha and TNF-beta, are able to reveal cytotoxic effect in pH-dependent manner. Therefore we investigated, whether CD95L may also reveal pH-dependent cytotoxicity. We analyzed influence of CD95L on U937 and K562 human cell lines at pH 5.1 and pH 7.4 using radioactive chromium release and tetrazolium salt (MTT) reduction assays. Expression of CD95 in both cell lines was estimated using RNase Protection Assay and FACS analysis. It has been found that short incubation of cells at pH 5.1 did not visibly affect their viability, as measured after 16 or 20 h. Incubation of U937 with CD95L at pH 7.4 resulted in a dose-dependent cell cytotoxicity. The effect was significantly augmented by incubation of cells with CD95L at pH 5.1. K562 cell line was resistant to CD95L at pH 7.4. This result correlated with the lack of CD95 expression in K562 cells. However, incubation at pH 5.1 resulted in a sensitization of K562 cells to CD95L. Our results suggest that CD95L, similarly to TNF-alpha, is able to reveal its cytotoxic activity in a receptor-independent manner and this activity strongly depends on pH of the environment.