Engineering Platforms for T Cell Modulation

Intraepithelial cytotoxic lymphocytes are associated with a poor prognosis in feline intestinal T-cell lymphoma

The expression of cytotoxic molecules in feline intestinal T-cell lymphoma cells was examined immunohistochemically using endoscopic samples of 50 cases. Cases included 14 large-cell lymphomas (LCLs) and 36 small-cell lymphomas (SCLs). Most LCL and some SCL exhibited marked erosion and villous atrophy. Clonal T-cell receptor (TCR) gene rearrangement was detected in 10/14 (71%) LCL cases and 33/36 (92%) SCL cases. No clonal immunoglobulin heavy chain (IgH) gene rearrangement was detected. Immunohistochemically, all cases were positive for CD3 and negative for CD79α, CD30, CD56, and Foxp3. LCLs were positive for CD8 in 13/14 cases (93%), T-cell intracellular antigen 1 (TIA1) in 14/14 cases (100%), and granzyme B in 6/14 cases (43%). SCLs were positive for CD8 in 28/36 cases (78%), TIA1 in 33/36 cases (92%), and granzyme B in 2/36 cases (6%). TIA1- and granzyme B-positive neoplastic lymphocytes were predominantly observed in the mucosal epithelium of 10/50 cases (20%) and 6/50 cases (12%), respectively. No significant differences in survival time were found based on cell size or epitheliotropism. However, cases with TIA1⁺ and/or granzyme B⁺ neoplastic lymphocytes predominantly in the mucosal epithelium had significantly shorter survival times (P < .05), suggesting that mucosal epithelium infiltration of neoplastic cells with a cytotoxic immunophenotype is a negative prognostic factor. Therefore, intraepithelial cytotoxic lymphocytes may be associated with mucosal injury and impaired intestinal function, leading to a poor prognosis in cats with intestinal T-cell lymphoma.

Adaptive Nanoparticle Platforms for High Throughput Expansion and Detection of Antigen-Specific T cells

T cells are critical players in disease; yet, their antigen-specificity has been difficult to identify, as current techniques are limited in terms of sensitivity, throughput, or ease of use. To address these challenges, we increased the throughput and translatability of magnetic nanoparticle-based artificial antigen presenting cells (aAPCs) to enrich and expand (E+E) murine or human antigen-specific T cells. We streamlined enrichment, expansion, and aAPC production processes by enriching CD8+ T cells directly from unpurified immune cells, increasing parallel processing capacity of aAPCs in a 96-well plate format, and designing an adaptive aAPC that enables multiplexed aAPC construction for E+E and detection. We applied these adaptive platforms to process and detect CD8+ T cells specific for rare cancer neoantigens, commensal bacterial cross-reactive epitopes, and human viral and melanoma antigens. These innovations dramatically increase the multiplexing ability and decrease the barrier to adopt for investigating antigen-specific T cell responses.

Effects of titanium dioxide nanoparticles on the myocardium of the adult albino rats and the protective role of β-carotene (histological, immunohistochemical and ultrastructural study)

Titanium dioxide nanoparticles (TiO₂ NPs) are the most produced nanomaterials. TiO₂ NPs are used as a drug carrier and molecular imaging vehicle in the cardiovascular system. We aimed to study TiO₂ NPs effects on the ventricular myocardium and evaluate the ameliorative effects of β-carotene (βC). Forty adult albino rats were divided into four groups: negative control group (Ι) received a distilled water. Treated group (II): received 20 mg/kg/day TiO₂NPs intraperitoneally. Protected group (III): received 10 mg/kg/day βC orally together with TiO₂ NPs in a dose of 20 mg/kg/day intraperitoneally. Positive control group (IV) was given βC orally in a dose of 10 mg/kg/day for 14 days. Sections were stained with hematoxylin & eosin, bromphenol blue (BPB), and periodic acid Schiff (PAS). Anti-desmin & anti-CD45 immunohistochemical staining and electron microscopic examination were performed. Group (II) revealed fragmented myofibrils and inflammatory infiltrations. In group (III), normal cardiomyocytes with less inflammatory infiltrations. The optical density of PAS and BPB staining and anti-desmin showed a very highly significant decrease in the group (II) versus the control groups (P < 0.001). A highly significant increase in the optical density of group (III) versus group (II) (P < 0.01). Also, the area percentage mean values of collagen fibers and anti-CD45 in the group (II) showed a very highly significant increase versus the control groups (P < 0.001). Group (III) revealed a very highly significant decrease in the area percentage versus group (II) (P < 0.001). In conclusion: TiO₂ NPs adversely affected the histological structure of the adult rat ventricular myocardium in acute exposure (14 days) and the damage was less with βC.

Synthetic 3D scaffolds for cancer immunotherapy

Recent clinical success of systemic cancer immunotherapy has paved the way for the next-generation therapeutics. Nevertheless, cancer immunotherapies, in particular combination therapies, are associated in some cases with severe side effects and low response rates. Synthetic scaffolds have emerged as a promising platform to deliver immunotherapeutic agents locally. Placed at strategic locations of the body, scaffolds can reduce side effects while increasing the concentration of the agent at the site of interest. Moreover, scaffolds can mimic the context, in which biochemical cues are presented in vivo to enhance cell modulation. Recent research has focused on designing three-dimensional (3D) scaffolds with specific properties to modulate the antitumor response at various stages of the cancer immunity cycle. As the number of immunotherapies in clinical trials is soaring, it is essential to critically evaluate the role that scaffolds can play in improving the safety and efficacy of existing and future therapies.

Beyond TCR Signaling: Emerging Functions of Lck in Cancer and Immunotherapy

In recent years, the lymphocyte-specific protein tyrosine kinase (Lck) has emerged as one of the key molecules regulating T-cell functions. Studies using Lck knock-out mice or Lck-deficient T-cell lines have shown that Lck regulates the initiation of TCR signaling, T-cell development, and T-cell homeostasis. Because of the crucial role of Lck in T-cell responses, strategies have been employed to redirect Lck activity to improve the efficacy of chimeric antigen receptors (CARs) and to potentiate T-cell responses in cancer immunotherapy. In addition to the well-studied role of Lck in T cells, evidence has been accumulated suggesting that Lck is also expressed in the brain and in tumor cells, where it actively takes part in signaling processes regulating cellular functions like proliferation, survival and memory. Therefore, Lck has emerged as a novel druggable target molecule for the treatment of cancer and neuronal diseases. In this review, we will focus on these new functions of Lck.