Cell-free scaffold from jellyfish Cassiopea andromeda (Cnidaria; Scyphozoa) for skin tissue engineering.

Disruption of the continuous cutaneous membrane in the integumentary system is considered a health problem of high cost for any nation. Several attempts have been made for developing skin substitutes in order to restore injured tissue including autologous implants and the use of scaffolds based on synthetic and natural materials. Current biomaterials used for skin tissue repair include several scaffold matrices types, synthetic or natural, absorbable, degradable or non-degradable polymers, porous or dense scaffolds, and cells capsulated in hydrogels or spheroids systems so forth. These materials have advantages and disadvantages and its use will depend on the desired application. Recently, marine organisms such as jellyfish have attracted renewed interest, because both its composition and structure resemble the architecture of human dermic tissue. In this context, the present study aims to generate scaffolds from Cassiopea andromeda (C. andromeda), with application in skin tissue engineering, using a decellularization process. The obtained scaffold was studied by infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), differential scanning calorimetry analysis (DSC), and scanning electron microscopy (SEM). Crystal violet staining and DNA quantification assessed decellularization effectiveness while the biocompatibility of scaffold was determined with human dermic fibroblasts. Results indicated that the decellularization process reduce native cell population leading to 70% reduction in DNA content. In addition, SEM showed that the macro and microstructure of the collagen I-based scaffold were preserved allowing good adhesion and proliferation of human dermic fibroblasts. The C. andromeda scaffold mimics human skin and therefore represents great potential for skin tissue engineering.

Human papillomavirus 13 in a Mexican Mayan community with multifocal epithelial hyperplasia: could saliva be involved in household transmission?

Multifocal epithelial hyperplasia (MEH) is a disease of the oral mucosa. Human papillomaviruses 13 and 32 have been detected in these lesions. We describe the epidemiology and clinical characteristics of patients with MEH in a rural community in the Mayan area of Mexico with 53 cases and 54 controls. Clinical and epidemiological data were collected through a direct interview. Oral cell samples were collected with a cytobrush. Subjects collected their own saliva sample in a sterile bottle. All samples were tested for HPV 13 and 32 by polymerase chain reaction using specific primers. Of the 53 patients and 54 healthy subjects, 56% were < 12 years old, 25% were males and 75% females. Evolution of the lesions was between two months and 17 years. The lesions affected lips, jugal mucosa, and tongue, 96% had multiple lesions. From 53 patients, fifty samples of oral cells and 31 samples of saliva were analyzed. HPV 13 was detected in 100% oral cell and 100% saliva samples studied. 16 healthy subjects were HVP 13 positive. A highly significant association of HPV 13 infection and MEH was found, as determined by chi square test (p = 0.00) Household transmission of HPV 13 may happen through saliva and the shared use of contaminated objects.