Bc. Elliot et al., IN-VITRO INHIBITION OF CRYPTOSPORIDIUM-PARVUM INFECTION BY HUMAN MONOCLONAL-ANTIBODIES, Infection and immunity, 65(9), 1997, pp. 3933-3935
Cryptosporidium parvum infection of the small epithelial intestine cau
ses unremitting diarrhea and malabsorption that can lead to chronic an
d sometimes fatal illness in patients with AIDS, The illness may be am
eliorated by passive oral immunoglobulin therapy, The objective of thi
s study was to produce anti-Cryptosporidium human monoclonal antibodie
s for evaluation as potential therapy, All human monoclonal cell lines
that produced C. parvum antibodies were originally generated from the
peripheral blood lymphocytes of a human immunodeficiency virus-serone
gative woman, She had recovered from C. parvum infection and had a hig
h specific antibody titer, Hybridization of these lymphocytes with a t
umor cell line was accomplished by hypo-osmolar electrofusion, Twelve
clones were identified by enzyme-linked immunosorbent assay (ELISA) as
secreting anti-Cryptosporidium antibodies after the initial hybridiza
tion. From the 12 positive clones, two high antibody-secreting clones,
17A and 17B, were maintained in long-term culture, A second hybridiza
tion produced two other human monoclonal cell lines, EC5 and BB2, Huma
n monoclonal antibody from the first two cell lines bound to C. parvum
sporozoites and oocysts by immunofluorescence, The ability of human m
onoclonal antibodies to inhibit C. parvum infection in vitro was asses
sed by using a human enterocyte cell line, HT29.74, The antibodies of
the four different human hybridomas inhibited infection by 35 to 68% (
P < 0.05) compared to a control irrelevant human monoclonal antibody d
erived in a similar fashion, Human monoclonal antibodies are candidate
molecules for immunotherapy of C. parvum infection.