Microneedles-Mediated Immunization Promotes Lung CD8+ T Cell Immunity.

Microneedle array (MNA) has proven more efficient in stimulating humoral immunity than intramuscular (IM) vaccination. However, its effectiveness in inducing pulmonary CD8+ T cells remains elusive, which is essential to the frontline defense against pulmonary viral infections like influenza and covid19 viruses. The current investigation reveals that superior CD8+ T cell responses are elicited by MNA immunization over intradermal (ID) or IM immunization using the model antigen ovalbumin (OVA), irrespective of whether or not the antigen is provided in the lung. Mechanistically, MNA immunization targeted the epidermal layer and stimulated predominantly Langerhans cells resulting in increased expression of α4ß1 adhesion molecule on CD8+ T cell surface, which may play a role in T-cell homing to the lung, whereas CD8+ T cells induced by IM immunization did not express the adhesion molecule sufficiently. CD8+ T cells with a lung-homing propensity were also seen after ID vaccination, yet to a much lesser extent.Accordingly, MNA immunization provided stronger protection against influenza viral infection than an ID or IM immunization. The observations offer insights into a strong cross-talk between epidermal immunization and lung immunity and are valuable for designing and delivering vaccines against respiratory viral infections.

Childhood Bacille Calmette-Guerin Vaccination and Its Association With Less Severe COVID-19 Pneumonia.

INTRODUCTION: The potential for Bacille Calmette-Guerin vaccination to mitigate COVID-19 severity and perhaps infection susceptibility has been hypothesized, attracting global attention given its off-target benefits shown in several respiratory viral infections. METHODS: In this retrospective study, patients with laboratory-confirmed COVID-19 from Wuhan Pulmonary Hospital, China were categorized into Bacille Calmette-Guerin‒vaccinated and nonvaccinated groups. Clinical records, demography, laboratory results, and chest computed tomography scans were extracted from electronic medical records and compared between the 2 groups. RESULTS: No adverse events were observed, except for an increased frequency of chills in the Bacille Calmette-Guerin‒vaccinated group compared with that in the unvaccinated group (p=0.014). There were no significant differences in oxygen demand for breathing, computed tomography scans, treatments, or outcomes between the 2 groups. However, Bacille Calmette-Guerin‒vaccinated group had significantly less severe pneumonia (p=0.028) and milder deficiency in liver function, consistent with a lower death rate than in the unvaccinated group. CONCLUSIONS: Bacille Calmette-Guerin vaccination received in childhood is associated with less severe COVID-19 pneumonia and milder liver function deficiency in addition to a lower death rate in Bacille Calmette-Guerin‒vaccinated patients than in nonvaccinated individuals.

[Analysis of baseline liver biochemical parameters in 324 cases with novel coronavirus pneumonia in Shanghai area].

Objective: To summarize the clinical characteristics and liver biochemical parameters of 324 cases admitted with novel coronavirus pneumonia in Shanghai area. Methods: Clinical data and baseline liver biochemical parameters of 324 cases with novel coronavirus pneumonia admitted to the Shanghai Public Health Clinical Center from January 20, 2020 to February 24, 2020 were retrospectively analyzed. Patients were divided into two groups based on the status of illness: mild type (mild and typical) and severe type (severe and critical).The differences in clinical data and baseline liver biochemical parameters of the two groups were described and compared. The t-test and Wilcoxon rank-sum test were used for measurement data. The enumeration data were expressed by frequency and rate, and chi-square test was used. Results: Of the 324 cases with novel coronavirus pneumonia, 26 were severe cases (8%), with median onset of 5 days, 20 cases were HBsAg positive (6.2%), and 70 cases (21.6%) with fatty liver, diagnosed with X-ray computed tomography. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), γ-glutamyl transferase (GGT), total bilirubin (TBil), albumin(ALB) and international normalized ratio (INR) of 324 cases at baseline were 27.86 ± 20.02 U/L, 29.33 ± 21.02 U/L, 59.93 ± 18.96 U / L, 39.00 ± 54.44 U/L, 9.46 ± 4.58 µmol / L, 40.64 ± 4.13 g / L and 1.02 ± 0.10. Of which, ALT was > than the upper limit of normal (> ULN), accounting for 15.7% (51/324). ALT and AST > ULN, accounting for 10.5% (34/324). ALP > ULN, accounting for 1.2% (4/324). ALP and GGT > ULN, accounting for 0.9% (3/324). INR > ULN was lowest, accounting for 0.6% (2/324). There were no statistically significant differences (P > 0.05) in ALT [(21.5 vs. 26) U / L, P = 0.093], ALP [(57 vs.59) U/L, P = 0.674], and GGT [(24 vs.28) U/L, P = 0.101] between the severe group and the mild group. There were statistically significant differences in AST (23 U/L vs. 34 U/L, P < 0.01), TBil (10.75 vs. 8.05 µmol / L, P < 0.01), ALB (35.79 ± 4.75 vs. 41.07 ± 3.80 g/L, P < 0.01), and INR (1.00 vs. 1.04, P < 0.01). Conclusion: The baseline liver biochemical parameters of 324 cases with novel coronavirus pneumonia in Shanghai area was comparatively lower and the liverinjury degree was mild, and the bile duct cell damage was rare.