L. Borradori et al., IGM AUTOANTIBODIES TO 180-KD AND 230-KD TO 240-KD HUMAN EPIDERMAL PROTEINS IN PREGNANCY, Archives of dermatology, 131(1), 1995, pp. 43-47
Background and Design: A previous study has suggested that there is a
novel entity among the polymorphous eruptions of pregnancy (PEP) assoc
iated with circulating anti-basement membrane zone IgM autoantibodies.
To determine if the presence of antibasement membrane zone IgM autoan
tibodies is a feature of PEP, serum samples from 52 patients with a PE
P, 69 healthy pregnant women, and 42 nonpregnant women were prospectiv
ely evaluated by indirect immunofluorescence using salt-split human sk
in as substrate. Serum samples were also tested by immunoblotting usin
g keratinocyte extracts and anti-human IgM antibodies. The reactivity
of some serum samples was examined using two recombinant bullous pemph
igoid antigen proteins. Results: The percentage of women with a PEP, h
ealthy pregnant women, and nonpregnant women who had antibasement memb
rane zone IgM antibodies by indirect immunofluorescence was similar: 1
2%, 10%, and 14% of cases, respectively. By immunoblotting, 14% of the
serum samples from the patients with a PEP, 12% of the serum samples
from the healthy pregnant women, but only 2% of the serum samples from
the nonpregnant women contained IgM antibodies that reacted with epid
ermal proteins of 180 and/or 230 to 240 kd. The recombinant bullous pe
mphigoid antigen proteins were not recognized by any of the serum samp
les that showed a reactivity by immunoblotting using keratinocyte extr
acts. Conclusion: There is no evidence for the existence of a novel en
tity of pregnancy defined by circulating antibasement membrane zone Ig
M autoantibodies. Immunoblotting detects IgM autoantibodies that react
with epidermal proteins of 180 and/or 230 to 240 kd. These autoantibo
dies appear to be more frequent in pregnant than in nonpregnant women.
Although the nature of the target antigen(s) remains to be establishe
d, pregnancy may be associated with low levels of IgM autoreactivity a
gainst epidermal proteins.