Longitudinal Assessment of Facial Hyperhidrosis Management: Evaluating the Utility and Quality of Life Improvements following Botulinum Toxin Injection.

Facial hyperhidrosis is a debilitating condition that can severely impact the quality of life. This study aimed to assess the long-term utility of Botulinum toxin type A therapy (BTA) for facial hyperhidrosis and its impact on quality of life over a one-year period. Conducted at the Pius Brinzeu Clinical Emergency Hospital in Timisoara, Romania, this longitudinal observational study involved 77 adult patients with primary facial hyperhidrosis. Participants received two sessions of Botulinum toxin injections (50 U IncoBTX-A each) and were evaluated at baseline, 6 months, and 12 months using the Hyperhidrosis Disease Severity Scale (HDSS), WHOQOL-BREF, Dermatology Life Quality Index (DLQI), and a bespoke survey. The study demonstrated significant reductions in HDSS scores from 3.6 ± 0.5 to 1.2 ± 0.8 post-treatment, sustained at 1.3 ± 0.6 at 12 months (p-value < 0.001). DLQI scores markedly decreased from 24.8 ± 4.2 to 6.2 ± 2.1 post-treatment, stabilizing at 6.5 ± 2.5 at 12 months (p-value < 0.001). Sweat production significantly dropped from 0.75 g ± 0.15 to 0.18 g ± 0.07 per 15 min (p-value < 0.001). WHOQOL-BREF scores improved notably in the mental domain from 66.7 ± 6.1 to 70.8 ± 5.2 at 12 months (p-value < 0.001), with physical and social domains also showing significant improvements. Correlation analysis revealed strong negative correlations between DLQI total score and HDSS (rho = -0.72, p-value < 0.001) and sweat production (rho = -0.68, p-value < 0.001). Regression analysis indicated significant predictors for DLQI total score, including HDSS (B Coefficient = -3.8, p-value < 0.001) and sweat production (B Coefficient = -2.2, p-value < 0.001). BTA therapy significantly improved the quality of life in facial hyperhidrosis patients, with lasting effects on symptom severity, sweat production, and quality of life domains. The correlation and regression analyses further substantiated the treatment's impact on both physical and psychological aspects. These findings advocate Botulinum toxin as a viable long-term treatment for facial hyperhidrosis.

Preclinical safety assessment of the suction-assisted intradermal injection of the SARS-CoV-2 DNA vaccine candidate pGO-1002 in white rabbit.

pGO-1002, a non-viral DNA vaccine that expresses both spike and ORF3a antigens of SARS-CoV-2, is undergoing phase 1 and phase 2a clinical trials in Korea and the US. A preclinical repeated-dose toxicity study in New Zealand white rabbits in compliance with Good Laboratory Practice (GLP) was conducted to assess the potential toxicity, local tolerance, and immunogenicity of the vaccine and GeneDerm suction device. The dose rate was 1.2 mg/head pGO-1002, and this was administered intradermally to a group of animals (eight animals/sex/group) three times at 2-week intervals, followed by a 4-week recovery period. After each administration, suction was applied to the injection site using the GeneDerm device. Mortality, clinical signs, body weight, food consumption, skin irritation, ophthalmology, body temperature, urinalysis, and clinical pathology were also monitored. Gross observations and histopathological evaluation were performed. Overall, pGO-1002 administration-related changes were confined to minor damage or changes at the injection site, increased spleen weight and minimal increased cellularity in white pulp. All changes of injection site were considered local inflammatory changes or pharmacological actions due to the vaccine with the changes in spleen considered consistent with vaccine-induced immune activation. All findings showed reversibility during the 4-week recovery period. Animals vaccinated with pGO-1002, administered by intradermal injection and followed by application of suction with GeneDerm, developed humoral and cellular responses against the SARS-CoV-2 antigens consistent with prior studies in rats. Collectively, it was concluded that the pGO-1002 vaccine was safe and effective under these experimental conditions and these data supported future human study of the vaccine, now known as GLS-5310, for clinical trial use.

A Call to Action by the Italian Mesotherapy Society on Scientific Research.

Mesotherapy (local intradermal therapy, LIT) is a technique used to slowly spread drugs in tissues underlying the site of injection to prolong the pharmacological effect with respect to intramuscular injection. Recommendations for proper medical use of this technique have been made for pain medicine and rehabilitation, chronic venous disease, sport medicine, musculoskeletal disorders, several dermatological conditions, skin ageing, and immune-prophylaxis. Although mesotherapy is considered a valid technique, unresolved questions remain, which should be answered to standardize methodology and dosing regimen as well as to define the right indications in clinical practice. New randomized controlled trials are needed to test single products (dose, frequency of administration, efficacy and safety). Even infiltration of substances for dermo-cosmetic purposes must be guided by safety and efficacy tests before being proposed by mesotherapy. In this article, we put forth a preclinical and clinical research plan and a health technology assessment as a call to action by doctors, researchers and scientific societies to aid national health authorities in considering mesotherapy for prevention, treatment and rehabilitation paths.

Assessment of cytotoxicity and sensitization potential of intradermally injected tattoo inks in reconstructed human skin.

BACKGROUND: The number of people within the European population having at least one tattoo has increased notably, and with it the number of tattoo-associated clinical complications. Despite this, safety information and testing regarding tattoo inks remain limited. OBJECTIVE: To assess cytotoxicity and sensitization potential of 16 tattoo inks after intradermal injection into reconstructed human skin (RHS). METHODS: Commercially available tattoo inks were injected intradermally into RHS (reconstructed epidermis on a fibroblast-populated collagen hydrogel) using a permanent makeup device. RHS biopsies, tissue sections, and culture medium were assessed for cytotoxicity (thiazolyl blue tetrazolium bromide assay [MTT assay]), detrimental histological changes (haematoxylin and eosin staining), and the presence of inflammatory and sensitization cytokines (interleukin [IL]-1α, IL-8, IL-18; enzyme-linked immunosorbent assay). RESULTS: Varying degrees of reduced metabolic activity and histopathological cytotoxic effects were observed in RHS after ink injection. Five inks showed significantly reduced metabolic activity and enhanced sensitization potential compared with negative controls. DISCUSSION: Using the RHS model system, four tattoo inks were identified as highly cytotoxic and classified as potential sensitizers, suggesting that allergic contact dermatitis could emerge in individuals carrying these inks. These results indicate that an RHS-based assessment of cytotoxicity and sensitization potential by intradermal tattoo ink injection is a useful analytical tool to determine ink-induced deleterious effects.

Aqueous intradermal low-dose house dust mite immunotherapy in tropical settings: a valid cost-effective approach for developing nations?

INTRODUCTION: Aqueous allergen injections, an effective and century-old technique, is considered a second-line approach in daily clinical practice. Inconveniences still surround conventional subcutaneous immunotherapy (SCIT) administration, such as a need for frequent injections, prolonged up-dosing schedules, elevated costs, and the unlikely possibility of a systemic reaction. The intradermal immunotherapy route (IDR) might favorably impact many of the aforementioned issues (Table 1). House dust mite (HDM) allergens are the main perennial sensitizers in the tropics, and as such, are solely employed in immunotherapy treatments. METHODS: We carried out a year-long real-life study in 25 perennial allergic rhinitis children, symptomatic on exposure to house dust, employing an intradermal low-dose allergen mix consisting of 50 ng of Dermatophagoides pteronyssinus/Dermatophagoides farinae and 120 ng of Blomia tropicalis, under a unique cost-wise protocol. Basal symptoms/signs and face Visual Analog Scale (fVAS) scores were recorded for 2 weeks and later compared with those registered throughout the 1-year treatment. Serum-specific IgG4 and IL-10 levels were employed in the assessment of the immune responses. RESULTS: Symptoms/signs and fVAS scores were significantly reduced from days 42 and 49, respectively, and remained so until treatment completion. Increases in specific IgG4's and IL-10 levels reflected significant immune responses. Injections were well tolerated and families reported improved health status (quality of life, QoL). CONCLUSIONS: A unique cost-effective immunotherapy alternative for deprived allergic communities in tropical settings is depicted; further research is needed.

The suitability of reconstructed human epidermis models for medical device irritation assessment: A comparison of In Vitro and In Vivo testing results.

The ISO 10993 standards on biocompatibility assessment of medical devices discourage the use of animal tests when reliable and validated in vitro methods are available. A round robin validation study of in vitro reconstructed human epidermis (RhE) assays was performed as potential replacements for rabbit skin irritation testing. The RhE assays were able to accurately identify strong irritants in dilute medical device extracts. However, there was some uncertainty about whether RhE tissues accurately predicted the results of the rabbit skin patch or intracutaneous irritation test. To address that question, this paper presents in vivo data from the round robin and subsequent follow-up studies. The follow-up studies included simultaneous in vitro RhE model and in vivo testing of round robin polymer samples and the results of dual in vitro/in vivo testing of currently marketed medical device components/materials. Our results show for the first time that for both pure chemicals and medical device extracts the intracutaneous rabbit test is more sensitive to detect irritant activity than the rabbit skin patch test. The studies showed that the RhE models produced results that were essentially equivalent to those from the intracutaneous rabbit skin irritation test. Therefore, it is concluded that RhE in vitro models are acceptable replacements for the in vivo rabbit intracutaneous irritation test for evaluating the irritant potential of medical devices.

Immune response and Raman scattering assessment in rats skin after contact with Fusarium oxysporum metabolites.

The secondary metabolites produced by Fusarium can cause disease and death when consumed and produce biological responses even in the absence of the microorganism. The IL-6, TNF-α and TGF-ß1 cytokines immune reactivity was associated with histopathological and physico-chemical changes in skin of immune competent rats after administration of Fusarium oxysporum crude extract. Rats were intradermally injected with 50 µl of 0.5 mg/ml crude extract and were euthanized at 3, 6, 12 and 24 h after injection. The inflammatory response was quantified by enzyme myeloperoxidase activity and by immunohistochemical method to detect the IL-6, TNF-α and TGF-ß1. Physico-chemical analysis was performed using FT-Raman Spectroscopy. The inflammatory response was most intense at 6 and 12 h after crude extract administration and the most significant histopathological changes were observed in the dermis. Myeloperoxidase activity was intense from 3 to 24 h after injection. The immunostaining of pro-inflammatory cytokines IL-6 and TNF-α peaked at 6 h. Immunostaining for TGF-ß1 was highest at 12 and 24 h. FT-Raman spectral analysis showed both, the most intense Fusarium interaction with the skin at 6 h, as revealed by the changes in the stretching of -CH bands (3100-2800 cm-1) in the dermis, and skin recovery trending after 12 h after crude extract injection. The results showed that secondary metabolites stimulated histopathologic changes and inflammatory responses even in the absence of the fungus, increasing myeloperoxidase activity and pro-inflammatory cytokine expression besides promoting physico-chemical changes.

Sequential Scalp Assessment in Hair Regeneration Therapy Using an Adipose-Derived Stem Cell-Conditioned Medium.

BACKGROUND: An adipose-derived stem cell-conditioned medium (ADSC-CM) reportedly exerts skin-rejuvenating and hair growth-promoting effects. In the therapeutic application of ADSC-CM for alopecia, changes to the interfollicular scalp remain unclear although some evidence has indicated hair growth-promoting effects. OBJECTIVE: To evaluate the effects of ADSC-CM not only on hair follicles, but also on the interfollicular scalp. METHODS: Forty patients (21 men, 19 women; age range, 23-74 years) with alopecia were treated by intradermal injection of ADSC-CM every month for 6 months. Eighty fixed sites on patients were investigated by trichograms, physiological examinations, and ultrasonographic examinations at 4 time points (before treatment and 2, 4, and 6 months after the initial treatment). RESULTS: Hair density and anagen hair rate increased significantly. As physiological parameters, transepidermal water loss value gradually increased, with significant differences at 4 and 6 months after the initial treatment, but hydration state of the stratum corneum and skin surface lipid level showed no obvious changes. As ultrasonographic parameters, dermal thickness and dermal echogenicity were increased significantly. CONCLUSION: Intradermal administration of ADSC-CM on the scalp has strong potential to provide regenerative effects for hair follicles and the interfollicular scalp. An adipose-derived stem cell-conditioned medium offers a promising prospect as an alternative treatment for alopecia.

Hyaluronic Acid Filler Injections for Nasolabial Folds in Asian Patients: A Treatment Plan Based on a Practical Nasolabial Assessment Method.

BACKGROUND: There are multiple techniques used to inject hyaluronic acid to minimize the appearance of nasolabial folds. These techniques vary in accordance with the etiology of the nasolabial folds. Based on our understanding of nasolabial anatomy and our experience with the injection of hyaluronic acid fillers, we herein summarize a systemic treatment plan based on a practical nasolabial fold assessment method. METHODS: From November 2015 to December 2017, 180 patients received hyaluronic acid injections in our clinic to improve the appearance of nasolabial folds. All patients were followed up for at least 1 month. All patients underwent our nasolabial fold assessment and were then treated with an appropriate plan. The therapeutic effect was assessed via the photonumeric wrinkle assessment scale. Patients with complications were monitored for up to 1 year. A follow-up survey was performed 1 month postoperatively, with the outcome rated as excellent, satisfactory, moderate, or unsatisfactory. RESULTS: Patients demonstrated a significant improvement in the appearance of the nasolabial folds. No infection or vascular complications occurred. The 1-month follow-up survey revealed that the patient satisfaction rate was 96.7% (excellent or satisfactory outcome). CONCLUSION: This systemic treatment method for nasolabial folds is effective, safe, and practical.

El costo de la belleza: Comunicación de seis casos clínicos con infección por micobacterias atípicas secundario a inyecciones intradérmicas y reacción a un dermoimplante de origen desconocido / The cost of beauty: six cosmetological clinical cases due to atypical mycobacterial infection secondary to intradermal injections plus reaction to foreign dermal implant

Resumen Comunicamos seis casos de mujeres quienes, tras la aplicación mediante mesoterapia con plasma rico en plaquetas, así como de un material de relleno intradérmico de origen desconocido, desarrollaron una infección en los sitios de inyección asociada a Mycobacterium massiliense, así como granulomas con reacción a cuerpo extraño. Aunque los cultivos fueron negativos, se logró la identificación del microorganismo por extracción de ADN de tejidos blandos obtenido por biopsia y posterior secuenciación del producto obtenido. Debido a la gran similitud en los cultivos de M. massiliense con la especie relacionada Mycobacterium abscessus, y a que tienen diferente respuesta terapéutica, las técnicas moleculares de diagnóstico son una opción real a considerar para administrar en forma precoz el tratamiento específico contra el patógeno y evitar la progresión de la infección.

We report six cases of female patients who, after the application by mesotherapy with platelet-rich plasma, as well as of an intradermal filler material of unknown origin, developed infection at the injection sites associated to Mycobacterium massiliense, as well as granuloma with reaction to foreign body. Although the cultures were negative, the identification of the microorganism was achieved by extraction of soft tissue DNA obtained by biopsy and sequencing the obtained product, with which the therapy was redirected against the particular species. Due to the great similarity in the culture between M. massiliense with the related species M. abscessus, to the required time for its growth, and to the different therapeutic response of each strain, molecular diagnostic techniques are a real option to consider to administer in an early way the appropriate treatment against the pathogen and prevent infection progression.

Wound-only injection of rabies immunoglobulin (RIG) saves lives and costs less than a dollar per patient by "pooling strategy".

Since 2008, we in Himachal Pradesh have used a "pooling strategy" to help patients save money by pooling vials of antirabies vaccine at a centralized hospital and sharing them using the intradermal technique. In 2014, there was an acute shortage of rabies immunoglobulins (RIG) and two patients died after four injections of rabies vaccine were administered without RIG, which was not commercially available. After an extensive literature review and technical and ethical committee clearances, in June 2014 we started to infiltrate equine RIG (eRIG) into wound/s only without the recommended systemic intramuscular (IM) injection. WHO recommended this technique in 2018. During the four-year period June 2014 to June 2018, 7506 of 10,830 patients exposed to suspected rabid animals were injected with eRIG in and around the wounds in a single clinic at DDU Hospital Shimla without any adverse outcomes. The average volume of eRIG used per patient was 0.75 mL and cost US$ 0.75. Of the 80% of patients who were followed up, all were healthy at the end of a year, including 26 patients bitten by laboratory-confirmed rabid dogs. The reaction rate after PEP administration also declined significantly. Since February 2018, Himachal has started following the new WHO recommendations on PEP regimens of three intradermal antirabies vaccines instead of four, thereby saving hundreds of vaccine vials that became useful during shortages of rabies vaccine in India. To date, more than 700 vaccine vials have been saved in a single clinic at DDU hospital during the past 6 months alone. Not giving PEP to patients who have consumed raw milk from a suspected rabid cow has also saved 62 vials. Currently, 90 "pooling centers" have been established for sharing of vaccine and eRIG vials in Himachal State, generating huge savings that have enabled the government to provide PEP free of charge to all. The new WHO guidelines are a positive step towards a rabies-free world by 2030.

Delayed-Onset Nodules to Differentially Crosslinked Hyaluronic Acids: Comparative Incidence and Risk Assessment.

BACKGROUND: Robust and long-term data on true incidence of delayed-onset nodules and immune tolerance of hyaluronic acid (HA) fillers are lacking. OBJECTIVE: To characterize the incidence of delayed nodules in Vycross (VYC) HA fillers compared with previously reported FDA and non-FDA data of all HA fillers. METHODS AND MATERIALS: The incidence of delayed nodules in all patients who had received VYC fillers in a 12-month period was assessed through a retrospective chart review. Nodule incidence for currently approved nonanimal-stabilized hyaluronic acid (NASHA) fillers was assessed using the FDA Summary of Safety and Effectiveness Data. RESULTS: Overall, 1,029 patients received 1,250 VYC filler treatments. Five patients developed delayed nodules to VOB, with an incidence of 1.0% per patient and 0.8% per syringe. No nodules were observed in patients who received VLR or VOL. All nodules were treated successfully using a combination of intralesional triamcinolone and hyaluronidase. Compared with other currently approved NASHA fillers, VOB is associated with a higher incidence of nodule formation. CONCLUSION: The introduction of VYC HAs has introduced a new variable that may be changing the immune tolerance of these substances, resulting in a higher incidence of delayed nodules than previously expected.

Assessment of Skin Physiology Change and Safety After Intradermal Injections With Botulinum Toxin: A Randomized, Double-Blind, Placebo-Controlled, Split-Face Pilot Study in Rosacea Patients With Facial Erythema.

BACKGROUND: Botulinum toxin (BTX) has been used cosmetically with good clinical efficacy and tolerable safety. OBJECTIVE: This randomized, double-blind, split-face clinical study aimed to investigate the efficacy and safety of intradermal BTX in patients with rosacea. MATERIALS AND METHODS: Twenty-four participants were enrolled and randomly given intradermal injections of BTX and normal saline in both cheeks. Clinician Erythema Assessment (CEA) score, Global Aesthetic Improvement Scale (GAIS) score, skin hydration, transepidermal water loss (TEWL), melanin content, erythema index, elasticity, and sebum secretions were evaluated at baseline and 2, 4, 8, and 12 weeks. RESULTS: On the BTX-treated side, the CEA score significantly decreased and the GAIS score significantly increased. The erythema index decreased at Weeks 4 and 8. Skin elasticity was improved at Weeks 2 and 4 and skin hydration, at Weeks 2, 4, and 8. However, TEWL and sebum secretion did not show significant differences. CONCLUSION: Intradermal BTX injections reduced erythema and rejuvenated the skin effectively and safely in patients with rosacea.

Healthcare utilization, provisioning of post-exposure prophylaxis, and estimation of human rabies burden in Madagascar.

In Madagascar, dog-mediated rabies has been endemic for over a century, however there is little data on its incidence or impact. We collected data over a 16-month period on provisioning of post-exposure prophylaxis (PEP) at a focal clinic in the Moramanga District and determined the rabies status of biting animals using clinical and laboratory diagnosis. We find that animal rabies cases are widespread, and clinic-based triage and investigation are effective ways to increase detection of rabies exposures and to rule out non-cases. A high proportion of rabies-exposed persons from Moramanga sought (84%) and completed PEP (90% of those that initiated PEP), likely reflecting the access and free provisioning of PEP in the district. Current clinic vial sharing practices demonstrate the potential for intradermal administration of PEP in endemic African settings, reducing vaccine use by 50% in comparison to intramuscular administration. A high proportion of PEP demand was attributed to rabies cases, with approximately 20% of PEP administered to probable rabies exposures and an additional 20% to low-to-no risk contacts with confirmed/probable animal or human cases. Using a simplified decision tree and our data on rabies exposure status and health-seeking behavior, we estimated an annual incidence of 42-110 rabies exposures and 1-3 deaths per 100,000 persons annually. Extrapolating to Madagascar, we estimate an annual burden of 282-745 human rabies deaths with current PEP provisioning averting 1499-3958 deaths each year. Data from other clinics and districts are needed to improve these estimates, particularly given that PEP availability is currently limited to only 31 clinics in the country. A combined strategy of mass dog vaccination, enhanced surveillance, and expanded access to PEP along with more judicious guidelines for administration could effectively reduce and eventually eliminate the burden of rabies in Madagascar.

Evaluating new rabies post-exposure prophylaxis (PEP) regimens or vaccines.

The development of human rabies vaccines has evolved dramatically from the first crude nerve tissue vaccine produced then administered in the presence of Louis Pasteur in 1885. New cell culture technology has enabled highly potent and well-tolerated rabies vaccines to be produced that have reduced the volume and number of doses required to save human lives after exposure. However, these highly potent vaccines are still unaffordable to many patients living at risk of exposure on a daily basis. The cost of post-exposure prophylaxis (PEP) is not only related to the direct cost of rabies biologicals and equipment but is also associated with indirect costs that patients incur as a result of travel, loss of work time (income loss), and accommodation over the period of time that a PEP regimen requires to be completed. This paper summarizes the particular criteria that the SAGE Working Group and WHO personnel reviewed as part of the evaluation process for recommending the new one-week intradermal vaccination regimen (2-2-2-0-0) for rabies post-exposure prophylaxis. These criteria included: Cost-effectiveness; evaluation of number of doses; seroconversion after vaccination; efficacy; safety; and patient follow-up.

Hyaluronan-based dissolving microneedles with high antigen content for intradermal vaccination: Formulation, physicochemical characterization and immunogenicity assessment.

The purpose of this study was to optimize the manufacturing of dissolving microneedles (dMNs) and to increase the antigen loading in dMNs to investigate the effect on their physicochemical properties. To achieve this, a novel single-array wells polydimethylsiloxane mold was designed, minimizing antigen wastage during fabrication and achieving homogeneous antigen distribution among the dMN arrays. Using this mold, hyaluronan (HA)-based dMNs were fabricated and tested for maximal ovalbumin (OVA) content. dMNs could be fabricated with an OVA:HA ratio as high as 1:1 (w/w), without compromising their properties such as shape and penetration into the ex vivo human skin, even after storage at high humidity and temperature. High antigen loading did not induce protein aggregation during dMN fabrication as demonstrated by complementary analytical methods. However, the dissolution rate in ex vivo human skin decreased with increasing antigen loading. About 2.7 µg OVA could be delivered in mice by using a single array with an OVA:HA ratio of 1:3 (w/w). Intradermal vaccination with dMNs induced an immune response similar as subcutaneous injection and faster than after hollow microneedle injection. In conclusion, results suggest that (i) the polydimethylsiloxane mold design has an impact on the manufacturing of dMNs, (ii) the increase in antigen loading in dMNs affects the microneedle dissolution and (iii) dMNs are a valid alternative for vaccine administration over conventional injection.

[The cost of beauty: six cosmetological clinical cases due to atypical mycobacterial infection secondary to intradermal injections plus reaction to foreign dermal implant]. / El costo de la belleza: Comunicación de seis casos clínicos con infección por micobacterias atípicas secundario a inyecciones intradérmicas y reacción a un dermoimplante de origen desconocido.

We report six cases of female patients who, after the application by mesotherapy with platelet-rich plasma, as well as of an intradermal filler material of unknown origin, developed infection at the injection sites associated to Mycobacterium massiliense, as well as granuloma with reaction to foreign body. Although the cultures were negative, the identification of the microorganism was achieved by extraction of soft tissue DNA obtained by biopsy and sequencing the obtained product, with which the therapy was redirected against the particular species. Due to the great similarity in the culture between M. massiliense with the related species M. abscessus, to the required time for its growth, and to the different therapeutic response of each strain, molecular diagnostic techniques are a real option to consider to administer in an early way the appropriate treatment against the pathogen and prevent infection progression.

Insertion-responsive microneedles for rapid intradermal delivery of canine influenza vaccine.

In this study, we present transcutaneous influenza vaccination using a novel tip-separable microneedle system called insertion-responsive microneedles (IRMNs). IRMNs are composed of dissolvable hyaluronic acid (HA) tips and biocompatible polycaprolactone (PCL) bases, the tip of which is instantly separated from the base during microneedle insertion and retraction. Vaccine antigens derived from canine influenza virus (A/canine/VC378/2012; H3N2) were successfully coated on HA tips by rapidly freezing the tips prior to coating. An ex vivo porcine skin insertion test showed that IRMNs were capable of penetrating the skin without tip breakage and releasing the coated materials within the skin. The thermal stability of the vaccine as determined by hemagglutination assay revealed that the coated vaccine partially maintained its activity when stored at 50 °C for 3 weeks, whereas the liquid form completely lost the activity. Immunization in guinea pigs showed that hemagglutination inhibition (HI) antibodies induced by IRMNs were two times higher than those induced by intramuscular (IM) injections. When challenged with influenza A/canine/Korea/01/2007 (H3N2) wild-type virus 2 weeks after the second vaccination, viral shedding was completely eliminated at 8 days post infection in both IRMNs and IM injection groups. Our results suggest that IRMNs have great potential for rapid and convenient vaccination, which will be particularly attractive for animal vaccinations.

Intravital imaging-based analysis tools for vessel identification and assessment of concurrent dynamic vascular events.

The vasculature undergoes changes in diameter, permeability and blood flow in response to specific stimuli. The dynamics and interdependence of these responses in different vessels are largely unknown. Here we report a non-invasive technique to study dynamic events in different vessel categories by multi-photon microscopy and an image analysis tool, RVDM (relative velocity, direction, and morphology) allowing the identification of vessel categories by their red blood cell (RBC) parameters. Moreover, Claudin5 promoter-driven green fluorescent protein (GFP) expression is used to distinguish capillary subtypes. Intradermal injection of vascular endothelial growth factor A (VEGFA) is shown to induce leakage of circulating dextran, with vessel-type-dependent kinetics, from capillaries and venules devoid of GFP expression. VEGFA-induced leakage in capillaries coincides with vessel dilation and reduced flow velocity. Thus, intravital imaging of non-invasive stimulation combined with RVDM analysis allows for recording and quantification of very rapid events in the vasculature.