Cimetidine enhances delayed-type hypersensitivity responses and serum interleukin (IL)-2, -10, -12, and IL-17 levels after burn injury in an animal model

Kinetics of Inflammatory Mediators in the Immune Response to Burn Injury: Systematic Review and Meta-Analysis of Animal Studies

Burns are often accompanied by a dysfunctional immune response, which can lead to systemic inflammation, shock, and excessive scarring. The objective of this study was to provide insight into inflammatory pathways associated with burn-related complications. Because detailed information on the various inflammatory mediators is scattered over individual studies, we systematically reviewed animal experimental data for all reported inflammatory mediators. Meta-analyses of 352 studies revealed a strong increase in cytokines, chemokines, and growth factors, particularly 19 mediators in blood and 12 in burn tissue. Temporal kinetics showed long-lasting surges of proinflammatory cytokines in blood and burn tissue. Significant time-dependent effects were seen for IL-1β, IL-6, TGF-β1, and CCL2. The response of anti-inflammatory mediators was limited. Burn technique had a profound impact on systemic response levels. Large burn size and scalds further increased systemic, but not local inflammation. Animal characteristics greatly affected inflammation, for example, IL-1β, IL-6, and TNF-α levels were highest in young, male rats. Time-dependent effects and dissimilarities in response demonstrate the importance of appropriate study design. Collectively, this review presents a general overview of the burn-induced immune response exposing inflammatory pathways that could be targeted through immunotherapy for burn patients and provides guidance for experimental set-ups to advance burn research.

A systemic review of taxanes and their side effects in metastatic breast cancer

Taxanes-containing chemotherapy constitutes an essential backbone for both early and metastatic breast cancer (mBC). However, the two major taxane drugs—paclitaxel and docetaxel—have distinct safety profiles. In this review, we summarize the safety outcome and management following treatment with both taxanes from selected clinical trials. We utilized PubMed to perform literature search before April 2021. Five phase III randomized controlled trials with reports of individual taxane adverse events (AEs) were included in this review. Grade 3/4 AEs were summarized and discussed extensively. The rates of grade 3/4 neutropenia were higher with docetaxel than with paclitaxel. For non-hematologic grade 3/4 AEs, peripheral neuropathy was more frequent with paclitaxel while fluid retention was more frequent with docetaxel. Compared to paclitaxel, docetaxel had a higher rate of grade 3/4 gastrointestinal AEs. Grade 3/4 myalgia were generally comparable between the two taxanes. Except for neutropenia, the incidence rate of grade 3/4 AEs of taxanes was generally manageable. Peripheral neuropathy was more common with paclitaxel while grade 3/4 neutropenia was more common with docetaxel.

H2-antagonist in IgE-mediated type I hypersensitivity reactions: what literature says so far?

Histamine is a monoamine synthesized from the amino acid histidine that is well-known for its role in IgE-mediated anaphylaxis but has shown pleiotropic effects on the immune system, especially in order to promote inflammatory responses. H₁-receptor antagonist are common drugs used in mild/moderate allergic reactions whereas H₂-receptor antagonist are commonly administered in gastric ulcer but showed some properties in allergy too. The EAACI guidelines for diagnosis and treatment of anaphylactic reactions recommend their use as third-line therapy in adjunct to H₁-antagonists. The purpose of this article is to produce a complete summary of findings and evidence known so far about the usefulness of H₂-receptor antagonist in allergic reactons.

Immunomodulatory properties of cimetidine: Its therapeutic potentials for treatment of immune-related diseases

Histamine exerts potent modulatory impacts on the cells of innate- [including neutrophils, monocytes, macrophages, dendritic cells (DCs), natural killer (NK) cells and NKT cells] and adaptive immunity (such as Th1-, Th2-, Th17-, regulatory T-, CD8⁺ cytotoxic T cells, and B cells) through binding to histamine receptor 2 (H2R). Cimetidine, as an H2R antagonist, reverses the histamine-mediated immunosuppression, as it has powerful stimulatory effects on the effector functions of neutrophils, monocytes, macrophages, DCs, NK cells, NKT cells, Th1-, Th2-, Th17-, and CD8⁺ cytotoxic T cells. However, cimetidine reduces the regulatory/suppressor T cell-mediated immunosuppression. Experimentally, cimetidine potentiate some immunologic activities in vitro and in vivo. The therapeutic potentials of cimetidine as an immunomodulatory agent were also investigated in a number of human diseases (such as cancers, viral warts, allergic disorders, burn, and bone resorption) and vaccination. This review aimed to provide a concise summary regarding the impacts of cimetidine on the immune system and highlight the cellular mechanisms of action and the immunomodulatory effects of this drug in various diseases to give novel insights regarding the therapeutic potentials of this drug for treatment of immune-related disorders. The review encourages more investigations to consider the immunomodulatory characteristic of cimetidine for managing of immune-related disorders.

Cimetidine: A Safe Treatment Option for Cutaneous Warts in Pediatric Heart Transplant Recipients

Abstract:Background andObjectives: Immunosuppressed individuals are at particularly increased risk for human papilloma virus-related infections. The primary objective of our study is to determine if there are any adverse effects associated with high-dose cimetidine treatment. A secondary objective is to report our experience with cimetidine in the treatment of cutaneous warts in pediatric heart transplant recipients. Methods and Results: This was a retrospective observational study. A total of 8 pediatric heart transplant recipients diagnosed with multiple recalcitrant warts were the subject of the study. All patients were treated with cimetidine (30-40 mg/kg/day) in two divided doses for 3 to 6 month durations. All patients had complete resolution of their lesions except 1 patient who had no clinical improvement. Of these 8 patients, one had recurrence of warts at one year follow-up, which resolved with restarting cimetidine therapy. One patient who had only 3 months of cimetidine therapy had immediate relapse after cimetidine was stopped. None of them had significant change in their tacrolimus trough, serum creatinine, and alanine transaminase levels. No adverse events were reported except one patient experienced mild gynecomastia. Conclusion: Cimetidine can be a safe and alternative treatment option for multiple warts in pediatric heart transplant recipients.

Induction of systemic and mucosal immunity against methicillin-resistant Staphylococcus aureus infection by a novel nanoemulsion adjuvant vaccine

The Gram-positive bacterial pathogen methicillin-resistant Staphylococcus aureus (MRSA) can cause infections in the bloodstream, endocardial tissue, respiratory tract, culture-confirmed skin, or soft tissue. There are currently no effective vaccines, and none are expected to become available in the near future. An effective vaccine capable of eliciting both systemic and mucosal immune responses is also urgently needed. Here, we reported a novel oil-in-water nanoemulsion adjuvant vaccine containing an MRSA recombination protein antigen, Cremophor EL-35^® as a surfactant, and propylene glycol as a co-surfactant. This nanoemulsion vaccine, whose average diameter was 31.34±0.49 nm, demonstrated good protein structure integrity, protein specificity, and good stability at room temperature for 1 year. The intramuscular systemic and nasal mucosal immune responses demonstrated that this nanoemulsion vaccine could improve the specific immune responses of immunoglobulin (Ig)G and related subclasses, such as IgG1, IgG2a, and IgG2b, as well as IgA, in the serum after Balb/c mice intramuscular immunization and C57 mice nasal immunization. Furthermore, this nanoemulsion vaccine also markedly enhanced the interferon-γ and interleukin-17A cytokine cell immune response, improved the survival ratio, and reduced bacterial colonization. Taken together, our results show that this novel nanoemulsion vaccine has great potential and is a robust generator of an effective intramuscular systemic and nasal mucosal immune response without the need for an additional adjuvant. Thus, the present study serves as a sound scientific foundation for future strategies in the development of this novel nanoemulsion adjuvant vaccine to enhance both the intramuscular systemic and nasal mucosal immune responses.