Sodium chloride

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vitro

Type of information:

other: publication

Adequacy of study:

weight of evidence

Study period:

1999

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The publication contains sufficient information to permit a meaningful evaluation of study results

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

publication

Title:

Contact sensitizers decrease 33D1 expression on mature Langerhans cells

Author:

Herouet et al

Year:

1999

Bibliographic source:

European Journal of Dermatology. Volume 9, Number 3, 185-90, April- May 1999, Revues

Materials and methods

Test guideline

Qualifier:

no guideline available

Principles of method if other than guideline:

Langerhans cells play a critical role in allergic contact hypersensitivity. In vivo, these cells capture xenobiotics that penetrate the skin and transport them through the lymphatic vessels into regional lymph nodes for presentation to T cells. During this migration step, Langerhans cells become mature dendritic cells according to their phenotype and their high immunostimulatory capacity. In vitro, when isolated from the skin and cultured for 3 days, Langerhans cells undergo similar phenotypic and functional maturation. In this study, the capacity of sensitizers, irritants and neutral chemicals to modulate the surface marker expression and morphology of pure mature murine Langerhans cells in vitro was examined

GLP compliance:

not specified

Type of study:

other: In this study, the capacity of sensitizers, irritants and neutral chemicals to modulate the surface marker expression and morphology of pure mature murine Langerhans cells in vitro was examined.

Test material

Test material information

Constituent 1

Reference substance name:

Sodium chloride

EC Number:

231-598-3

EC Name:

Sodium chloride

Cas Number:

7647-14-5

Molecular formula:

ClNa

IUPAC Name:

sodium chloride

Constituent 2

Reference substance name:

23-598-3

IUPAC Name:

23-598-3

Details on test material:

- Name of test material: Sodium chloride
- Sourced from: Sigma-Aldrich, St. Louis, MO, USA
- Other: Highly pure sensitizers [2,4-dinitrobenzenesulfate (DNBS), p-phenylenediamine (pPD), 4-ethoxymethylene-2-phenyl-2-oxazolin-5-one (Oxa) and mercaptobenzothiazole (MBT)], irritants [sodium lauryl sulfate (SLS), dimethyl sulfoxide (DMSO) and benzalkonium chloride (BC)] and other chemicals [sodium chloride (NaCl) and methyl nicotinate (Nico)] were purchased from Sigma-Aldrich, Saint Louis, MO, USA.

In vivo test system

Test animals

Species:

mouse

Strain:

Balb/c

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Janvier, Le Genest-Saint-Isle, France
- Age at study initiation: 10-12 weeks
- Weight at study initiation: not specified in the publication
- Housing: not specified in the publication
- Diet: not specified in the publication
- Water: not specified in the publication
- Acclimation period: not specified in the publication

ENVIRONMENTAL CONDITIONS
- Temperature (°C): not specified in the publication
- Humidity (%): not specified in the publication
- Air changes (per hr): not specified in the publication
- Photoperiod (hrs dark / hrs light): not specified in the publication

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

other:

Vehicle:

no data

Induction 2

Concentration / amount:

not specified in the publication

Challenge

Challenge 1

Route:

other:

Vehicle:

no data

Challenge 2

Concentration / amount:

not specified in the publication

No. of animals per dose:

not specified in the publication

Details on study design:

not applicable

Challenge controls:

not applicable

Positive control substance(s):

not specified

Remarks:

not applicable

Study design: in vivo (LLNA)

Concentration:

not applicable

No. of animals per dose:

not applicable

Details on study design:

not applicable

Statistics:

The means ± SEM were calculated for all values. Differences between treated groups and controls were tested using Dunnett's two-sided pairwise multiple comparison t-test

Results and discussion

Positive control results:

not applicable

In vivo (LLNA)

Results

Results 1

Parameter:

SI

Remarks on result:

other: not applicable

Results 2

Parameter:

other: disintegrations per minute (DPM)

Remarks on result:

other: not applicable

Any other information on results incl. tables

As shown by their high forward and side scatter FACScan parameters, as well as by microscopic observation, gated cells recovered after a 3-day-migration period were homogeneous, large sized and viable. The cells expressed high levels of MHC class I and class II molecules, costimulatory molecules (CD86, CD80) and adhesion molecules (CD11c, CD54), as well as the dendritic cell-specific marker DEC-205. They also expressed two dendritic cell-specific markers, 33D1 and 4F7. CD105. All these characteristics confirmed that the migratory cells were mature LC. These cells were used to study the effects of sensitizing and irritating chemicals.

 

The immediate direct effects of DNBS on mature LC morphology and phenotype were assessed. No morphological changes nor cell size variations were observed in 5 out of 5 experiments. However a 3-fold increase in cell granularity (SSC determination) was observed with the highest non toxic DNBS concentration that has been determined by trypan blue exclusion test. Phenotypic analysis showed no immediate surface modulation of the molecules involved in cellular interactions (MHC class I and class II molecules, CD80 or CD86 and CD54). However, 33D1 expression was persistently, immediately and markedly reduced (40-80%) at the surface of DNBS-haptenized mature LC in 5 out of 5 experiments. Moreover, the DNBS-induced decrease in 33D1 expression was concentration-dependent and restricted to this surface molecule. Sensitizers induced a specific decrease in 33D1 expression on mature LC

 

To determine if the specific decrease in 33D1 expression was restricted to strong sensitizers such as DNBS, morphological changes and modulation of surface markers were studied with other chemicals. Chemicals used were strong (Oxa), moderate (pPD) or weak (MBT) sensitizers, irritants (SLS, DMSO, BC) and neutral chemicals (NaCl, Nico).

Cell size was generally unaffected by the chemicals. The only exception was SLS, a detergent,that reduced cell size and induced numerous membrane ruffles. LC granularity increased only in the presence of the sensitizers pPD and DNBS.

 

All the sensitizers reduced 33D1 expression at the surface of mature LC. This occurred within 30 min of contact, and again affected only 33D1 expression. In contrast to the effect of DNBS, that of pPD was not concentration-dependent, in the dose range studied. Neither the neutral agents nor irritants, DMSO and BC, had an effect on 33D1 expression. SLS affected not only 33D1 expression but also that of the other markers tested.

Applicant's summary and conclusion

Conclusions:

Contact with 4 sensitizers (2,4-dinitrobenzenesulfate, 4-ethoxymethylene-2-phenyl-2-oxazolin-5-one, p-phenylenediamine, mercaptobenzo-thiazole) resulted in a rapid, specific, marked fall in 33D1 expression, a murine specific dendritic cell marker. No effect was observed with 2 neutral chemicals (sodium chloride, methyl nicotinate) or 2 irritants (dimethyl sulfoxide, benzalkonium chloride). Nevertheless, sodium lauryl sulfate, a very irritant detergent, altered morphology and down-regulated all membrane markers

Executive summary:

Langerhans cells play a critical role in allergic contact hypersensitivity. In vivo, these cells capture xenobiotics that penetrate the skin and transport them through the lymphatic vessels into regional lymph nodes for presentation to T cells. During this migration step, Langerhans cells become mature dendritic cells according to their phenotype and their high immunostimulatory capacity. In vitro, when isolated from the skin and cultured for 3 days, Langerhans cells undergo similar phenotypic and functional maturation. In this study, the capacity of sensitizers, irritants and neutral chemicals to modulate the surface marker expression and morphology of pure mature murine Langerhans cells in vitro was examined.

Contact with 4 sensitizers (2,4-dinitrobenzenesulfate, 4-ethoxymethylene-2-phenyl-2-oxazolin-5-one, p-phenylenediamine, mercaptobenzo-thiazole) resulted in a rapid, specific, marked fall in 33D1 expression, a murine specific dendritic cell marker. No effect was observed with 2 neutral chemicals (sodium chloride, methyl nicotinate) or 2 irritants (dimethyl sulfoxide, benzalkonium chloride). Nevertheless, sodium lauryl sulfate, a very irritant detergent, altered morphology and down-regulated all membrane markers.