Safety and Tolerability of the Adeno-Associated Virus Vector, AAV6.2FF, Expressing a Monoclonal Antibody in Murine and Ovine Animal Models

Adeno-associated virus (AAV) vector mediated expression of therapeutic monoclonal antibodies is an alternative strategy to traditional vaccination to generate immunity in immunosuppressed or immunosenescent individuals. In this study, we vectorized a human monoclonal antibody (31C2) directed against the spike protein of SARS-CoV-2 and determined the safety profile of this AAV vector in mice and sheep as a large animal model. In both studies, plasma biochemical parameters and hematology were comparable to untreated controls. Except for mild myositis at the site of injection, none of the major organs revealed any signs of toxicity. AAV-mediated human IgG expression increased steadily throughout the 28-day study in sheep, resulting in peak concentrations of 21.4–46.7 µg/ mL, demonstrating practical scale up from rodent to large animal models. This alternative approach to immunity is worth further exploration after this demonstration of safety, tolerability, and scalability in a large animal model.

Assessment of the incidence of accessory hepatic arteries: literature review

Modern medicine is developing towards application of endovascular techniques such as trans-arterial hepatic chemoembolization. They displace classic open procedures. However, their correct planning and performance depend on the knowledge pre-operative detection of hepatic arterial anatomical variations. The main abnormality that may generate complications during radiological and surgical procedures is occurrence of an accessory hepatic artery. In the present study we propose our own classification of the variability observed in the vessels based on cases reported in the literature. It analyzes more types of variations as compared to previous trials. A great advantage of this study is also a description of different pathological and frequently life-threatening conditions associated with hepatic arteries. This study is of value to medical practitioners, e.g. surgeons.

Six-headed coracobrachialis muscle

The coracobrachialis muscle is the smallest muscle of the anterior compartment of the arm. It is responsible for flexion and abduction in the glenohumeral joint. The coracobrachialis muscle is morphologically variable both, in its insertion and origin. Moreover, some additional heads or structures may also occur. The present report describes a six-headed coracobrachialis muscle originated as a common junction with the the short head of the biceps brachii muscle from the coracoid process. All of these heads insert into the medial surface of the humeral shaft. It is important to note that the musculocutaneous nerve was piercing the fourth belly. Other heads were innervated by branches from the musculocutaneous nerve. Knowledge of the morphological variability of this muscle is essential not only for anatomists but for clinicians as well.

Five-headed superior omohyoid

The omohyoid is an infrahyoid muscle with two bellies. It is responsible for lowering and positioning of the hyoid bone. It is morphologically variable in the origin, insertion and morphology of its bellies. Quantitative variations of the superior belly of the omohyoid muscle are not common. We present a case of a five-headed superior omohyoid, and a short clinical review related to this muscle. All the bellies had their origin in an intermediate tendon and were attached to the hyoid bone. The volume of its superior part was greater than usual. Knowledge of the anatomy of this muscle is important, especially for surgeons operating in the anterolateral neck region.

Case report of the double headed extensor hallucis longus

BACKGROUND

We present a case report of double-headed extensor hallucis longus (EHL) with potential clinical significance.

MATERIALS AND METHODS

Cadaveric dissection of the right lower limb of a 70-year-old female at death was performed for research and teaching purposes at the Department of Anatomical Dissection and Donation, Medical University of Lodz. The limb was dissected using standard techniques according to a strictly specified protocol. Each head and tendon of the muscle was photographed and subjected to further measurements.

RESULTS

During dissection, an unusual type of EHL muscle was observed. It consisted of two muscle bellies, a main tendon and an accessory tendon. Both muscle bellies were located on anterior surface of the fibula and the interosseous membrane. The main tendon insertion was located on the dorsal aspect of the base of the distal phalanx of the big toe, while the accessory tendon insertion was located medially.

CONCLUSIONS

The EHL muscle is highly morphologically variable at both the point of origin and the insertion. Knowledge of its variationsis connected to several pathologies such as foot drop, tendonitis, tendon rupture, and anterior compartment syndrome.

Anatomical variations of the calcaneofibular ligament in human foetuses

Ligaments anatomy often show a huge anatomy variations between species and individuals. For example calcaneofibular ligaments (CFL) characterize the great variability of morphological shape or presence of additional bands. The aim of this study was to propose first anatomical classification of CFL concerning on human fetuses. We investigated thirty spontaneously-aborted human fetuses aged 18-38 weeks of gestation at death. Sixty lower limbs (30 left and 30 right) fixed in 10% formalin solution were examined. The morphological variability of CFL was assessed. Four types of CFL morphology were observed. Type I was characterized by a band shape. This was the most common type, occurring in 53% of all cases. Based on our study we are proposing a classification based on four morphological types of CFL. Types 2 and 4 are further divided into subtypes. Present classification may be useful to better understand the anatomical development of ankle joint.

The ulnar head of the pronator teres muscle originating from the third head of the biceps brachii: a very rare case

The biceps brachii is located in the anterior compartment of the arm, which can show numerous morphological variations. During anatomical dissection, an interesting additional muscle was found: the third head of the biceps brachii originated from the short head of the same muscle. The 97.77 mm long muscle belly was directed medially over the arm and then passed into the common tendon (15.97 mm), which thereafter split into aponeurosis and tendon. The 26.33 mm aponeurosis passed and joined the fascia of the forearm. The tendon of the third head of the biceps brachii then gave rise to the ulnar head of the pronator teres muscle. Such an accessory structure could cause neurovascular compression involving the brachial artery and median nerve. Knowledge of the morphological variability of this region is essential not only for anatomists but also for clinicians.

Anatomical variation of co-existing bilaminar tensor of the vastus intermedius muscle and new type of sixth head of the quadriceps femoris

BACKGROUND

We present a case report of quadriceps femoris (QF) with co-existing bilaminar tensor of the vastus intermedius (TVI) muscle and new type of sixth head.

MATERIALS AND METHODS

Cadaveric dissection of left thigh of a 72-year-old man was performed for research and teaching purposes at the Department of Anatomical Dissection and Donation, Medical University of Lodz. The left lower limb was dissected using standard techniques according to a strictly specified protocol. Each head of the muscle was photographed and subjected to further measurement.

RESULTS

During dissection, an unusual type of TVI muscle was observed. It consisted of two surfaces, superficial and deep. In addition, sixth head of QF muscle grew out from the vastus medialis muscle.

CONCLUSIONS

The knowledge of the existence and possible variations of additional heads of QF muscle is necessary during diagnostic process of muscle strains. Moreover, according to course of tendons that heads may take part in patella stabilisation.

A morphological study on the sphenoid bone ligaments' ossification pattern

PURPOSE

The sphenoid bone (SB) extracranial ligaments (ECRLs) are the pterygoalar and pterygospinous ligaments (PTAL and PTSL) that are located at the SB lateral pterygoid plate, and inferior to the foramen ovale (FO). Their ossification may affect the mandibular nerve's distribution. The intracranial ligaments' (ICRLs) ossification (the caroticoclinoid ligament-CCLL, the anterior and posterior interclinoid ligaments-AICLL and PICLL) may impede the approaches to the sella. This study highlights the incidence of the ossified ECRLs and ICRLs location, their type (partial, or complete), considering laterality, gender, age, and ligaments' simultaneous presence.

METHODS

The sample consisted of 156 Greek adult dried skulls of both genders and variable age.

RESULTS

Ossified ligaments were identified in 57.05%, predominantly extracranially (42.31%, P = 0.003). ECRLs were predominantly identified unilaterally (30.13%, P < 0.001). The majority of the ossified ICRLs were predominantly identified in male skulls (31.1%, P = 0.048) and the majority of the ECRLs (52.8%, P = 0.028) were predominantly identified at the age of 60 years and above. The PTAL was the most ossified (32.69%), followed by the CCLL (24.36%), the PTSL (16.03%), the PICLL (6.41%), and the AICLL (4.49%).

CONCLUSIONS

Detailed knowledge of the SB morphology and ligaments' ossification extent is essential to improve the technique of the FO percutaneous approach, and sellar approaches, to minimize complications.

Variant origin of three main coronary ostia from the right sinus of Valsalva: report of a rare case

Observing anomalies in the origin of the coronary arteries is a rare but recognised scenario during coronarography. All the major coronary arteries originating from the right sinus of Valsalva is an extremely rare anomaly, its reported incidence being 0.008% in angiographic studies. Most coronary artery variations are benign and are therefore found accidentally or postmortem. However, some anomalies in the origin of the coronary arteries are associated with myocardial ischaemia and a higher risk of sudden cardiac death. Herein, we report a sporadic case of anomalous origin of the coronary arteries, in which the right coronary artery, anterior interventricular artery and left circumflex artery arise separately from the right sinus of Valsalva, each originating from a separate ostium. Regardless of their low incidence rate, coronary artery anomalies can cause serious technical challenges during coronary angiography and percutaneous interventions because of the unusual location and course of the artery. Echocardiography, computed tomography, and magnetic resonance imaging can be useful in such cases.

Clinical significance of morphological variations of the inferior phrenic arteries

The rapid development of sciences such as genetics and molecular biology offers hope that better therapeutic methods can be developed and diagnosis and treatment made more effective. However, we must not forget that the basis for understanding the complex mechanisms of diseases and associated symptoms is knowledge of the relevant location and correlation among organs. In the present study, we focus on the clinical significance of the inferior phrenic artery. The diaphragm is a muscular structure that separates the abdominal and chest cavities. Thanks to this position, the inferior phrenic artery is much more significant than formerly assumed. A rich network of collaterals makes this vessel important in the development of neoplasms and metastases. Knowledge of anatomical variants of the inferior phrenic artery is also crucial for radiological procedures such as embolisation. The main aim of this study is to review the involvement of the inferior phrenic artery in physiological and pathophysiological processes. This work has value for all practicing doctors, especially radiologists and surgeons.

Analysis of the impact of pluronic acid on the thermal stability and infectivity of AAV6.2FF

BACKGROUND

The advancement of AAV vectors into clinical testing has accelerated rapidly over the past two decades. While many of the AAV vectors being utilized in clinical trials are derived from natural serotypes, engineered serotypes are progressing toward clinical translation due to their enhanced tissue tropism and immune evasive properties. However, novel AAV vectors require formulation and stability testing to determine optimal storage conditions prior to their use in a clinical setting.

RESULTS

Here, we evaluated the thermal stability of AAV6.2FF, a rationally engineered capsid with strong tropism for lung and muscle, in two different buffer formulations; phosphate buffered saline (PBS), or PBS supplemented with 0.001% non-ionic surfactant Pluronic F68 (PF-68). Aliquots of AAV6.2FF vector encoding the firefly luciferase reporter gene (AAV6.2FF-ffLuc) were incubated at temperatures ranging from -20°C to 55°C for varying periods of time and the impact on infectivity and particle integrity evaluated. Additionally, the impact of several rounds of freeze-thaw treatments on the infectivity of AAV6.2FF was investigated. Vector infectivity was measured by quantifying firefly luciferase expression in HEK 293 cells and AAV particle integrity was measured by qPCR quantification of encapsidated viral DNA.

CONCLUSIONS

Our data demonstrate that formulating AAV6.2FF in PBS containing 0.001% PF-68 leads to increased stability and particle integrity at temperatures between -20℃ to 21℃ and protection against the destructive effects of freeze-thaw. Finally, AAV6.2FF-GFP formulated in PBS supplemented with 0.001% PF-68 displayed higher transduction efficiency in vivo in murine lung epithelial cells following intranasal administration than vector buffered in PBS alone further demonstrating the beneficial properties of PF-68.

AAV-Vectored Expression of Marburg Virus-Neutralizing Antibody MR191 Provides Complete Protection From Challenge in a Guinea Pig Model

Although there are no approved countermeasures available to prevent or treat disease caused by Marburg virus (MARV), potently neutralizing monoclonal antibodies (mAbs) derived from B cells of human survivors have been identified. One such mAb, MR191, has been shown to provide complete protection against MARV in nonhuman primates. We previously demonstrated that prophylactic administration of an adeno-associated virus (AAV) expressing MR191 protected mice from MARV. Here, we modified the AAV-MR191 coding sequence to enhance efficacy and reevaluated protection in a guinea pig model. Remarkably, 4 different variants of AAV-MR191 provided complete protection against MARV, despite administration 90 days prior to challenge. Based on superior expression kinetics, AAV-MR191-io2, was selected for evaluation in a dose-reduction experiment. The highest dose provided 100% protection, while a lower dose provided ∼88% protection. These data confirm the efficacy of AAV-mediated expression of MR191 and support the further development of this promising MARV countermeasure.

The morphological variability of fibularis tertius origin in human foetuses

BACKGROUND

The purpose of this study was to characterize the morphology of the fibularis tertius (FT) in human fetuses, and to provide a classification based on its modes of origin in human fetuses.

METHODS

The material comprised 100extremities from 50 spontaneously aborted human fetuses (19 male, 31 female, 100 lowerlimbs in total), aged 18- 38 weeks of gestation. These were dissected and the presence or absence of the FT muscle as well as the type of its proximal attachment were determined, and the FT was measured morphometrically.

RESULTS

The FT was present in 50% of fetuses. Four types of FT muscle origin were identified. The most common was Type 2, characterized by an origin on the middle third of the fibula and the intermuscular septum. Three other types were observed: Type 1 with an origin located on proximal third of the fibula and to the intermuscular septum, Type 3 characterized by an absent muscle belly, and an independent tendon originating from the that of the extensor digitorum longus, and Type 4 with an origin located on the distal third of the fibula and the intermuscular septum.

CONCLUSIONS

The fibularis tertius demonstrates high morphological variability, with the most common origin located on third of the fibula and to the intermuscular septum.

Anatomical variations of the biceps brachii insertion: a proposal for a new classification

BACKGROUND

The biceps brachii (BB) muscle is one of the three muscles located in the anterior compartment of the of the arm. It insertion consists of two parts. The first part - main tendon - attached in the radial tuberosity and the second part - lacertus fibrosus (LF) - in the fascia of the forearm flexors.The intention of research was to reveal the morphological diversity of the insertion of this muscle. Thanks to the results of this work, have been created a classification of the distal attachment of BB. The results of that research can be used to further develop surgical procedures in the given region.

MATERIALS AND METHODS

Eighty (40 left, and 40 right, 42 female, 38 male) upper limbs fixed in 10 % formalin solution were examined.

RESULTS

Was observed three types of the insertion of the BB. Type I was characterized by a single tendon and occurred most frequently in 78.75% of the examined limbs. The second most common type was Type II which was characterized by a double tendon and was observed in 13.75% of all the limbs. The last and least common was Type III which was characterized by three tendons and occurred in 7.5% of the examined limbs. Additionally, the type of lacertus fibrosus (LF) was analyzed. In eight (10%) specimens it was absent, i.e. in two specimens with type II insertion and six specimens with type III, p = 0.0001. Therefore, it may be deduced that Type III BB insertion tendon predisposes to LF deficiency.

CONCLUSIONS

The biceps brachii tendon is characterized by high morphological variability. The new classification proposes three types of distal attachment: type I - one tendon; type II - two separated band-shaped tendons; type III - three separated band-shaped tendons. The presence of Type III BB tendon predisposes to a lack of LF.

Embryological approach to the morphology of the ligamentum mucosum of the human knee joint

PURPOSE

The ligamentum mucosum is a ligamentous structure within the synovial layer of the knee joint capsule. It usually arises from the infrapatellar fat pad and is inserted into the intercondylar notch of the femur. In recent years, more attention has been paid to this structure because of its clinical significance. Despite the growing attention, the complex morphology of the ligamentum mucosum has led to many misunderstandings among the scientists and clinicians. Therefore, the main objective of this study was to characterize the morphology of the ligamentum mucosum and its attachment points, classify it, and evaluate its prevalence.

METHODS

Classical anatomical dissection was performed on 70 lower limbs of human fetuses fixed in 10% formalin solution. Morphology was carefully assessed, and morphometric measurements were performed. The types revealed were classified.

RESULTS

The ligamentum mucosum was present in 100% of all 70 specimens examined. Two types were detected. Type I (65.71%) - "cord-like". This type was the most common and is characterized by a single longitudinal ligament. The proximal attachment of the ligamentum mucosum was located in the middle of the infrapatellar fat, and the distal attachment was at the tip of the intercondylar notch. Type II (34.29%) - "vertical septum". This type is less common, but its morphology is much more complex compared to type I. It is wider and thicker than type I. Proximally, it is attached to the infrapatellar fat pad and distally through the entire intercondylar notch down to the anterior surface of the anterior cruciate ligament. It divides the joint cavity into medial and lateral sides.

CONCLUSION

The ligamentum mucosum exhibits high morphologic variability, and the view that it is a vestigial remnant of the embryologic development of the knee should be reconsidered. We have proposed an anatomical classification of its types in human fetuses, which is a valuable addition to existing knowledge and will hopefully change the approach of clinicians and scientists.

Unusual sensory innervation of the dorsal hand and why we should bear this variation in mind

Detailed knowledge of the anatomy and different variations of the superficial branch of the radial nerve could be of great importance not only to anatomists but also to clinicians. A predominant radial nerve supply to the dorsum of the hand is rare. Herein, we present an unusual case of unilateral sensory innervation of the dorsal hand found during routine anatomical dissection of a 72-year-old at death male Caucasian cadaver. We also present a brief discussion of the reported variation and emphasize its potential clinical implications.

A new type of the coracobrachialis muscle

The coracobrachialis muscle belongs to the anterior group of the brachial region. Its main functions are flexion and adduction at the glenohumeral joint. It is highly morphologically variable, especially in the number of bellies, place of origin or insertion, and its relationship to the musculocutaneous nerve. Accessory structures associated with the coracobrachialis muscle include the coracobrachialis brevis or coracobrachialis longus muscle. The present case describes a three-headed coracobrachialis muscle with two such additional structures. One of these has a tendinous origin connected to the periosteum and located on the surgical neck of the humerus. Its insertion is fused with the third head of the coracobrachialis muscle. The other has a proximal attachment fused with the capsule of the shoulder joint, and its distal attachment is fused with the third head of the coracobrachialis muscle in place of its connection with the short head of the biceps brachii. This could result in better stabilization of the glenohumeral joint; on the other hand, it could limit operational access during treatment of subscapularis tears.

Branching pattern of the internal iliac artery accompanied by a venous anastomosis: rare vascular variations

The ability to navigate the complex and often deceptive branching patterns of the internal iliac artery can be decisive in planning and performing surgeries within the lesser pelvis. The following case report presents a peculiar quadruple division of the internal iliac artery, accompanied by a venous anastomotic structure. Apart from the posterior and anterior trunks, the superior vesicle and iliolumbar arteries arose independently from the internal iliac artery. The division was surrounded by a venous oval, compressing certain branches and potentially complicating surgical access. Due to the uncommon course of the internal iliac artery and the presence of the anastomosis, a possible nerve root compression has been identified. Both clinical significance and classification method of the case are discussed. Knowledge of this anatomical variation is valuable for both diagnosis and surgery, especially within the specialties of urology, gynaecology and general surgery.

Adeno-associated virus mediated expression of monoclonal antibody MR191 protects mice against Marburg virus and provides long-term expression in sheep

Vectored monoclonal antibody (mAb) expression mediated by adeno-associated virus (AAV) gene delivery leads to sustained therapeutic mAb expression and protection against a wide range of infectious diseases in both small and large animal models, including nonhuman primates. Using our rationally engineered AAV6 triple mutant capsid, termed AAV6.2FF, we demonstrate rapid and robust expression of two potent human antibodies against Marburg virus, MR78 and MR191, following intramuscular (IM) administration. IM injection of mice with 1 × 1011 vector genomes (vg) of AAV6.2FF-MR78 and AAV6.2FF-MR191 resulted in serum concentrations of approximately 141 μg/mL and 195 μg/mL of human IgG, respectively, within the first four weeks. Mice receiving 1 × 1011 vg (high) and 1 × 1010 vg (medium) doses of AAV6.2FF-MR191 were completely protected against lethal Marburg virus challenge. No sex-based differences in serum human IgG concentrations were observed; however, administering the AAV-mAb over multiple injection sites significantly increased serum human IgG concentrations. IM administration of three two-week-old lambs with 5 × 1012 vg/kg of AAV6.2FF-MR191 resulted in serum human IgG expression that was sustained for more than 460 days, concomitant with low levels of anti-capsid and anti-drug antibodies. AAV-mAb expression is a viable method for prolonging the therapeutic effect of recombinant mAbs and represents a potential alternative "vaccine" strategy for those with compromised immune systems or in possible outbreak response scenarios.