IN VITRO ASSAYS
In Vitro Assays provides a fast and reliable measure of efficacy
and safety. By screening rapidly your formulation you can reach
a faster turnaround for your development program.
BioVolutions uses in vitro tissue equivalent models to
evaluate the permeability and toxicity of our final product formulations.
In vitro human tissue models have become increasingly important
as replacements for or as complements to traditional animal-based
toxicity testing. BioVolutions protocols, in collaboration with Apredica can
determine the permeability and toxicity potential of your API or
final product formulation.
Service |
Description |
Comments |
Skin Absorption OECD428 |
In Vitro permeability and toxicity
across human skin is measured to estimate the absorption
of a test substance into human skin. |
Human skin equivalents are placed
in Franz Diffusion chambers The permeant solution is
then pipetted onto the stratum corneum and receiver
samples are then assayed for permeant concentration, the
flux (moles/cm2/hr) is determined for each time interval,
and a plot of flux versus time is constructed. The permeability
coefficient, kp, is then calculated. |
Caco-2 Cell Intestinal
Absorption |
In vitro permeability
and toxicity of a test substance across differentiated monolayers
of CaCO-2 cells is measured to estimate human intestinal
permeability. |
The CaCO-2 permeability assay
is considered to be the industry gold standard for in
vitro prediction of in vivo human intestinal
permeability and bioavailability of orally administered drugs. |
Ocular Absorption |
This human tissue model is useful
in determining permeability and irritation/inflammation of
a test substance. |
Human-derived epidermal keratinocytes
which have been cultured to form a stratified, squamous epithelium
similar to that found in the cornea serve as a tissue equivalent
to evaluate the ophthalmic product formulations. |
Skin Permeability and Toxicity |
|
Epidermal tissue or full-thickness samples (EpiDerm™, MatTek
Corporation) are placed in Franz Diffusion chambers.
The permeant solution is then pipetted onto the stratum corneum
(top layer of EpiDerm™) and readings are taken following
the established permeation protocol for that permeation device.
At each time point, the entire receiver solution is typically removed,
stored, and replaced with fresh receiver solution. All receiver
samples are then assayed for permeant concentration, the flux (moles/cm2/hr)
is determined for each time interval, and a plot of flux versus
time is constructed. The permeability coefficient, kp, is then
calculated.
Receiver solution samples can also be assayed for metabolism-related
components. It is also advisable to check the potential cytotoxicity
of the permeant solution by performing the MTT ET-50 Tissue Viability
Assay on the tissue after completing the permeability
test.
EpiDerm™ is a normal (non-transformed), human cell-derived,
metabolically active, 3-dimensional organotypic in vitro skin model.
It closely mimics human epidermis, both structurally and biochemically,
and does so in a very reproducible manner. Proven EpiDerm™ percutaneous
absorption protocols allow researchers to quantitatively measure
the permeability characteristics of their experimental materials.
A growing body of data indicates that EpiDermFT™ (full thickness
skin including Epidermis and Dermis layers) effectively provides
a non-animal means to assess dermal toxicology and skin research
issues.
The protocols for using the EpiDermFT™ System (Full thickness
skin equivalent including dermis and epidermis) are clear and straightforward.
EpiDermFT has been utilized with several common tests of cytotoxicity
and irritancy, including MTT, IL-la, PGE2,
MMP-1 often in conjunction with assay determination by ELISA.
Technicians find EpiDermFT's rigid substrate design easier to handle
in routine repetitive testing environments and scientists find
that they are able to perform discriminating tests due to low background
interference.
Skin Pigmentation Studies
The MelanoDerm™ Skin Model exhibits in vivo-like
morphological and ultrastructural characteristics which are uniform
and highly reproducible. Normal Human Melanocytes (NHM) localized
in the basal cell layer of MelanoDerm™ are dendritic and
spontaneously produce melanin granules which progressively populate
the layers of tissue. When cultured for up to 3 weeks (post-shipment),
cultures become increasingly pigmented with retention of normal
epithelial morphology. Cultures containing NHM derived from black
donors show increased pigmentation versus those containing Caucasian-derived
or Asian-derived NHM; all three types of cultures are distinctly
darker than NHM-free cultures (EpiDerm™). The topical application
of known inhibitors of melanogenesis significantly reduce melanin
production and macroscopic darkening. Conversely, NHM within the
tissue will respond to known stimulants of melanogenesis, such
as -melanocyte stimulating hormone and -fibroblast growth factor,
to produce tissues which darken faster than untreated controls.
Various cosmetic and pharmaceutical laboratories are actively seeking
alternatives to expensive and time consuming clinical and whole
animal testing. Many companies have initiated MelanoDerm™ testing
to assess the ability of their raw materials and final product
formulations to modulate skin pigmentation. A growing body of data
demonstrates that MelanoDerm provides an inexpensive, effective
means of assessing various skin pigmentation issues while avoiding
species extrapolation and the use of laboratory animals.
Oral and Intestinal Permeability and Toxicity |
|
BioVolutions is using an in vitro tissue equivalent (Caco-2 and
EpiOral™ to evaluate our final oral product formulations.
Oral Permeability and Toxicity
BioVolutions uses the human equivalent tissues developed by MatTek (EpiOral™ and
EpiGengival™) which consist of normal, human-derived epithelial
cells to determine oral permeability and irritancy. Morphologically,
oral tissue models closely parallel native human tissues. The cells
have been cultured to form multilayered, highly differentiated
models of the human buccal (EpiOral) and gingival (EpiGingival)
phenotypes MatTek.
Intestinal Permeability and Toxicity
In vitro permeability and toxicity across differentiated
monolayers of CaCO-2 cells is measured to estimate human intestinal
permeability. CaCO-2 cell monolayers spontaneously differentiate
to express morphological and functional characteristics of mature
small-intestinal enterocytes. CaCO-2 cells grown on permeable filter
supports form tight junctions. Permeability across CaCO-2
cell monolayers is used to predict human permeability of drug candidates,
to perform in-depth mechanistic and absorption studies, to study
the effects of transporters on permeability, and transporter-mediated
drug-drug interactions. The CaCO-2 permeability assay is considered
to be the industry gold standard for in vitro prediction
of in vivo human intestinal permeability and bioavailability
of orally administered drugs. The FDA recommends that drug-drug
interactions should be performed during drug development (FDA Guidance
for Industry. Drug interaction studies - study design, data analysis,
and implications for dosing and labeling.September, 2006)
Ocular Permeability and Toxicity |
|
BioVolutions is using an in vitro tissue equivalent (EpiOcular™ from MatTek)
to evaluate our final ophthalmic product formulations.
MatTek's EpiOcular™ corneal
model consists of normal, human-derived epidermal keratinocytes
which have been cultured to form a stratified, squamous epithelium
similar to that found in the cornea. The epidermal cells, which
are cultured on specially prepared cell culture inserts using serum
free medium, differentiate to form a multi-layered structure which
closely parallels the corneal epithelium.
This human tissue model is useful in determining permeability and
irritation/inflammation for actively seeking alteratives to whole
animal and clinical testing.
Vaginal Permeability and Toxicity |
|
BioVolutions is using an in vitro tissue equivalents (EpiVaginal™ from MatTek)
to evaluate our final product formulations.
The EpiVaginal™ tissue models exhibit in vivo-like morphological
and growth characteristics which are uniform and highly reproducible.
EpiVaginal™ is a multilayered tissue consisting of an organized
basal layer and multiple non-cornified layers analogous to native
human vaginal-ectocervical tissue. The tissue expresses cytokeratin
K14 in the basal and supra basal layers and cytokeratin K13 in
the suprabasal tissue layers.
This human tissue model is useful in determining permeability
and irritation data for actively seeking alternatives to animal
and clinical testing.
Please contact BioVolutions for
additional information.
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