Liposomal propranolol for treatment of infantile hemangioma at compounding pharmacies

Infantile hemangiomas (IH) are common benign soft tissue tumors, frequently affecting infants. While Propranolol Hydrochloride (Pro HCl) has emerged as a promising treatment for IH, its topical application remains challenging due to the need for stable and efficacious carriers. This study investigates the potential of preformulated liposomes as carriers for topical delivery of Pro HCl for the treatment of IH in compounding pharmacies. Liposomes loaded with Pro HCl were prepared using active pharmaceutical ingredient or commercially available propranolol tablets and various dilution media, including Water for Injection (WFI), Dextrose 5%, and NaCl 0.9%. The physicochemical properties of the liposomal formulations (Pro HCl content, encapsulation efficiency, loading capacity, and colloidal stability) were assessed over a 90-day storage at 4 °C. In vitro release kinetics and transdermal permeation of Pro HCl from liposomes were also evaluated. Liposome properties were influenced by the dilution medium. Pro HCl content remained stable in liposomes encapsulating API (Lipo-Pro), regardless of the dilution medium. Lipo-Pro showed sustained drug release over time, suggesting its potential for maintaining therapeutic levels. Pro HCl exhibited enhanced transdermal permeability from Lipo-Pro compared to aqueous solution, indicating its potential for topical IH treatment. Preformulated liposomes offer a stable and effective carrier for Pro HCl, potentially suitable for extemporaneous preparations in compounding pharmacies. Their enhanced transdermal permeability presents a promising alternative for topical IH treatment. This study provides valuable insights into the development of innovative and effective drug delivery strategies for managing IH, with future research focusing on in vivo applications and therapeutic potential.

Effects of in utero exposure to cyclophosphamide in mice. II. Assessment of immunocompetence of offspring from 5 to 10 weeks of age

Offspring of mice treated with cyclophosphamide (Cy; 1, 2.5 or 5 mg/kg) during pregnancy (6-18 days of gestation) and tested for immunocompetence from 5 to 10 weeks of age were found to have defective reticuloendothelial clearance. The main effects were: a) increased elimination half time (T 1/2) of 51Cr-labeled SRBC from circulation, b) decreased liver uptake of 51Cr and c) impaired ability of the spleen, mostly affecting the female pups, to compensate for decreased liver uptake. The highest dose group suffered the most pronounced effects. This group was also found to have increased IgG immunoglobulin levels at 7 weeks of age. IgG antibody production in response to specific antigenic stimulation and delayed hypersensitivity reactions to oxazolone did not appear to be affected by Cy treatment.

Effects of rifampin treatment on contact sensitivity reactions to oxazolone in Balb/C mice

Treatment of mice with rifampin (Ri, 100-200 mg/kg) affected the course of contact sensitivity (CS) reactions to oxazolone. The effects which were seen as either partial inhibition or enhancement of the response, under one set of conditions, could be abrogated or even reversed if conditions of either induction, elicitation and time of measuring reactions were altered. In addition, amount of Ri used for treatment and time of treatment in relation to the induction of CS reactions also influenced the effects observed.

Preparation and immunological properties of procaine-protein conjugates

Procaine was conjugated to BSA and rat and rabbit Gf using the carbodiimide method and 14C-procaine as a tracer. The composition of the conjugates could be varied depending on the time of incubation and the concentration of procaine in the reaction mixture. Procaine-BSA conjugates were soluble in water or saline. However, procaine conjugates to rat or rabbit Gf were not readily soluble in saline. These conjugates were good for immunization purposes, but it was cumbersome to work with them when clear solutions were needed, as in the immunochemical procedures used in this study. The immunological properties of the conjugates were studied in rats and rabbits. Rats responded with production of IgGa and precipitating antibodies to the procaine group, but IgE antibodies to the immunogen could not be detected. Furthermore, precipitating antibodies towards the procaine group were raised in rabbits. When BSA was the protein carrier, antibodies to the carrier molecule were also detected in both rats and rabbits. The conjugates of procaine to rat or rabbit Gf did not elicit antibody response to the carrier molecular when used in the homologous species. Hapten inhibition studies suggested that, in the rabbit, antibodies were also produced with specificity directed towards the molecular configuration of the hapten-carrier bond.

Immunological properties of dialysis retentates from penicillin

Retentates from benzylpenicillin preparations marketed in Canada were used in immunological studies in order to determine if they were immunogenic in experimental animals with respect to anaphylactic antibody production. The retentates obtained consisted mainly of penicillin polymers. Impurities of protein nature were either insignificant or absent. The penicillin polymers were found to be non-immunogenic in Albino Wistar rats, Wistar Furth rats and Hartley guinea pigs. Furthermore, they were unable to effect positive PCA tests in rats passively sensitized to the penicilloyl determinant.

Production of rat homocytotropic antibodies using low dose, long term oral exposure to penicillin G

Sera from 15 patients with immediate hypersensitivity reactions to penicillin G gave positive responses in the rat mast cell test (RMCT) indicating the presence of IgE-type antibodies in the sera. Five sera were from patients who had had reactions to penicillin 15 to 22 years previously without known re-exposure to this antigen. To explore the possibility that non-therapeutic exposure to penicillin may have produced continued sensitization in these patients, an animal model system was developed to explore the efficacy of low dose, long term oral exposure to penicillin G in rats for producing homocytotropic antibodies in these animals. It was found that when rats were given penicillin G in their drinking water at concentrations of 0.1 to 1 U/ml over a period of 1 to 3 months they produced serum IgE and IgGa antibodies. In addition, IgE antibodies were actively bound to the peritoneal mast cells of these animals. The presence of circulating or cell bound antibodies was detected using the rat mast cell test. It was also shown that rats given penicillin G orally for 1 month were more prone to antibody production after a single intramuscular injection of penicillin G compared to a control group receiving only the intramuscular injection of this antigen. The results of this study are discussed in terms of possible non-therapeutic sensitization towards penicillin G in the human population.

Production of anaphylactic antibodies to drugs in experimental animals. I. Benzylpenicillin

Studies were undertaken to determine if animals exposed to benzylpenicillin could produce anaphylactic antibodies to the drug moiety. For this purpose, Albino Wistar rats were divided into four groups. Two groups of animals were immunized with benzylpenicillin using either the intraperitoneal or the subcutaneous route. The remaining two groups were used for feeding experiments. The animals were bled upon termination of the experiments; their sera were collected and pooled per group. The pooled sera were tested for the presence of anaphylactic antibodies. Histamine release from rat mast cells under the appropriate conditions was used as an indicator of antibody production. Penicilloylpolylysine and benzylpenicillin were both employed to determine antibody specificity. It was found that sera from all groups of animals contained anaphylactic antibodies with specificity towards the penicilloyl group and "benzylpenicillin".

Interrelationship of human IgE antibody and allergen in the rat mast cell technique

The present study was undertaken to determine the dose-response relationship between human IgE-type antibodies and a specific allergen using the rat mast cell technique. Using sera from ragweed-sensitive individuals, it was found that the higher the IgE antibody levels (as measured by the P-K test) the lower the concentration of ragweed antigen needed to elicit a response. Antigen titration was useful in (a) distinguishing 14 individuals allergic to ragweed from 8 non-allergic volunteers, (b) in determining relative levels of IgE antibody in these sera, and (c) in following relative changes of IgE antibody levels in untreated patients during and after the ragweed season.