Contact-allergy time

The most commonly used techniques for the in vivo evaluation of the
cellular immune response include intracutaneous testing with
microbial recall antigens or sensitization with neoantigens. The
reliability of these tests for the individual patient usually is
low due to the lack of standardization and quantification. Moreover
only the efferent branch of the immune response can be judged. The
dinitrochlorobenzene-contact allergy time (DNCB-CAT) is a
quantitative approach for the assessment of the cellular immune
response. 2% DNCBointment is applied on the upper arm in a 1 cm2
area. On the following days patch-testing with 0.05% DNCB-ointment
is done on the homolateral forearm in alternating localizations
till an allergic contact dermatitis reaction appears. As assessed
in patients with malignant melanoma (MM, n=\\5) and with
lymphoproliferative disorders (LD, η = 25), the DNCB-CAT correlates
with the age of the patients and can be expressed by a formula
given by the age (years) χ factor (MM = 0.16; LD = 0.17) + constant
figure (MM = 5.5; LD = 4.3). There was no significant difference
between the two groups or subgroups investigated. By DNCB-CAT
quantitative analysis of the cellular immune response in vivo is
possible. It is an appropriate model for further investigations of
the cellular immunity under different clinical, histological,
prognostic, and therapeutic aspects.