Post-vaccination serum cytokines levels correlate with breakthrough influenza infections

Enhancing flu vaccine responses in older adults: preliminary insights from the ISOLDA study on immunosenescence and antioxidant and anti-inflammatory approaches

Aging is frequently characterized by an inadequate primary vaccine response, likely due to immunosenescence and inflamm-aging, a low-level, chronic inflammatory state. Both aspects increase the susceptibility of older adults to viral and bacterial infections, resulting in a higher frequency and severity of infectious diseases. In this preliminary study, a cohort of 52 individuals was recruited and divided into two groups: young (age range 21-35) and older adults (> 60 years old). Peripheral blood mononuclear cells (PBMCs) were collected before (time 0, T0) and after (time 1, T1) the immunization with a tetravalent influenza vaccine. Then, T cell immunophenotyping analysis was conducted to investigate how aging and influenza vaccination influence T cell responses. Additionally, the anti-inflammatory and antioxidant effects of oleuropein (OLE), a secoiridoid extracted from extra virgin olive oil, alone or in combination with BIRB 796, a potent inhibitor of p38 MAPK, were explored to enhancing the impact of influenza virus on T cell activation, aiming to identify potential alternatives or complementary strategies to improve traditional flu-vaccine formulations. Statistically significant observations were noted for a decrement in CD8 + T naïve and an increase of effector memory between the young and older adults after flu-vaccination. Moreover, preliminary findings indicate anti-inflammatory and antioxidant properties of OLE and BIRB 796 on T cell responses, particularly regarding Reactive Oxygen Species/Reactive Nitrogen Species modulation, with a trend toward the decrease of pro-inflammatory cytokines (i.e., Interferon-γ (INF-γ), Tumor Necrosis Factor-α (TNF-α)), αalthough without statistical significance.

TRAIL and IP-10 dynamics in pregnant women post COVID-19 vaccination: associations with neutralizing antibody potency

Introduction

The aim of this study is to investigate changes in TNF-related apoptosis-inducing ligand (TRAIL) and gamma interferon-induced protein 10 (IP-10) after COVID-19 vaccination in pregnant women and to explore their association with neutralizing antibody (Nab) inhibition.

Methods

The study evaluated 93 pregnant women who had previously received two (n=21), three (n=55) or four (n=17) doses of COVID-19 vaccine. Also we evaluated maternal blood samples that were collected during childbirth. The levels of TRAIL, IP-10 and Nab inhibition were measured using enzyme-linked immunosorbent assays (ELISA).

Results and discussion

Our study revealed four-dose group resulted in lower TRAIL levels when compared to the two-dose and three-dose groups (4.78 vs. 16.07 vs. 21.61 pg/ml, p = 0.014). The two-dose group had reduced IP-10 levels than the three-dose cohort (111.49 vs. 147.89 pg/ml, p=0.013), with no significant variation compared to the four-dose group. In addition, the four-dose group showed stronger Nab inhibition against specific strains (BA.2 and BA.5) than the three-dose group. A positive correlation was observed between TRAIL and IP-10 in the two-dose group, while this relationship was not found in other dose groups or between TRAIL/IP-10 and Nab inhibition. As the doses of the COVID-19 vaccine increase, the levels of TRAIL and IP-10 generally increase, only by the fourth dose, the group previously vaccinated with AZD1222 showed lower TRAIL but higher IP-10. Despite these changes, more doses of the vaccine consistently reinforced Nab inhibition, apparently without any relation to TRAIL and IP-10 levels. The variation may indicate the induction of immunological memory in vaccinated mothers, which justifies further research in the future.

Respiratory pathogenic microbial infections: a narrative review

Respiratory infectious diseases have long been recognised as a substantial global healthcare burden and are one of the leading causes of death worldwide, particularly in vulnerable individuals. In the post COVID-19 era, there has been a surge in the prevalence of influenza virus A and other multiple known viruses causing cold compared with during the same period in the previous three years, which coincided with countries easing COVID-19 restrictions worldwide. This article aims to review community-acquired respiratory illnesses covering a broad spectrum of viruses, bacteria, and atypical microorganisms and focuses on the cluster prevalence of multiple known respiratory pathogens in China, thereby providing effective prevention and control measures.

Clinical Application of In Vitro Tests for COVID-19 Vaccine Delayed Hypersensitivity Diagnostics

Drug hypersensitivity reactions can be classified as immediate or delayed. While diagnostic options for immediate reactions are well developed and standardized, delayed reactions (in many cases type IV according to Gell and Coombs) are a challenge for allergy work-up. In recent years, some in vitro markers have been proposed and used for delayed reactions, such as contact dermatitis. Primary strategy: Avoidance is difficult to achieve, especially for COVID-19 vaccinations, when immunity against infection is extremely important. The aim of our study was to evaluate the application of in vitro delayed hypersensitivity tests in COVID-19 vaccines. Seven patients with a positive history of severe delayed drug allergy were enrolled. Vein blood was collected to stimulate cells with the tested vaccines (Comirnaty, Janssen, Spikevax) and excipients with the assessment of CD40L, CD69, IL-2, IL-4, IL-6, IL-10, IFNgamma, TNFalfa, and intracellular markers: granulysin and INFgamma. In addition, basophile activation tests, patch tests, skin prick tests, and intradermal tests were performed with the tested vaccine. Finally, the decision was made to either administer a vaccine or resign. Two out of seven patients were considered positive for drug hypersensitivity in the in vitro test according to the high vaccine stimulation index measured with CD69 (6.91 and 12.18) and CD40L (5.38 and 15.91). All patch tests, BATs, and skin tests were negative. Serum interleukin measurements were inconclusive as the impact of the vaccine itself on the immunity system was high. Intracellular markers gave uncertain results due to the lack of stimulation on the positive control. CD69 and CD40L could be reliable in vitro markers for delayed hypersensitivity to COVID-19 vaccines. Patch tests, skin tests, BATs, and serum interleukins did not confirm their usefulness in our study.

Pleiotropic Effects of Influenza Vaccination

Influenza vaccines are designed to mimic natural influenza virus exposure and stimulate a long-lasting immune response to future infections. The evolving nature of the influenza virus makes vaccination an important and efficacious strategy to reduce healthcare-related complications of influenza. Several lines of evidence indicate that influenza vaccination may induce nonspecific effects, also referred to as heterologous or pleiotropic effects, that go beyond protection against infection. Different explanations are proposed, including the upregulation and downregulation of cytokines and epigenetic reprogramming in monocytes and natural killer cells, imprinting an immunological memory in the innate immune system, a phenomenon termed "trained immunity". Also, cross-reactivity between related stimuli and bystander activation, which entails activation of B and T lymphocytes without specific recognition of antigens, may play a role. In this review, we will discuss the possible nonspecific effects of influenza vaccination in cardiovascular disease, type 1 diabetes, cancer, and Alzheimer's disease, future research questions, and potential implications. A discussion of the potential effects on infections by other pathogens is beyond the scope of this review.