Aims-To analyse the distribution of OV-TL 3 and MOv18 in normal ovaria
n tissue to determine which antibody is most suitable for (radio)immun
otherapy of ovarian carcinoma. Methods-The distribution of OV-TL 3 and
MOv18 was determined using immunohistochemistry and flow cytometry. R
esults-Epithelial and other cells in many tissues, and leucocytes in p
eripheral blood, bone marrow and spleen stained positively with OV-TL
3. The staining pattern of MOv18 in normal tissues was more restricted
and was confined to epithelial cells in the lung, kidney, pancreas, s
alivary gland, ovary, Fallopian tubes, and cervix. Reactivity was also
observed with pneumocytes in the lung, tubuli in the kidney, acinar c
ells in the salivary gland and pancreas, in the placenta, and with Kup
ffer cells in the liver. The staining pattern of chimeric MOv18 was id
entical with the murine form. OV-TL 3 and MOv18 reacted with 100% and
98% (45/46) of the 46 tested epithelial ovarian cancers, respectively.
In ovarian carcinoma tissue homogeneous staining of epithelial cells
was observed with OV-TL 3 and more heterogeneous staining with MOv18.
In 12 and nine patients, respectively, a difference in staining intens
ity for OV-TL 3 and MOv18 was observed between various tumour samples
from the same patient. Conclusion-MOv18 has greater therapeutic potent
ial because of its restricted reactivity with normal tissues and espec
ially, in contrast to OV-TL 3, its lack of reactivity with haematopoie
tic cells.