K. Gopalkrishnan et al., Use of acridine orange to evaluate chromatin integrity of human spermatozoa in different groups of infertile men, ANDROLOGIA, 31(5), 1999, pp. 277-282
To study the sperm chromatin compactness various methods, such as acidic an
iline blue or acridine orange staining, have been applied. Due to its metac
hromatic properties, acridine orange dye fluoresces green with double- and
red with single-stranded DNA. Samples (n=181) were evaluated and grouped as
follows: group I, normal recently fertile; group II, male having female pa
rtner with repeated early pregnancy loss; group III, male with varicocele;
and group TV in-vitro fertilization and intrauterine insemination failures.
Routine semen analyses were carried out in all the cases. Amorphous partic
ulate matter as observed under phase contrast microscope was graded on the
scale of nil to ++++. Fixed smears were stained with an aqueous solution of
acridine orange and viewed under a fluorescence microscope. Two hundred ce
lls were counted and the percentage of fluorescence calculated. Groups II,
III and IV exhibited significantly low green fluorescence compared with the
control group. The study also indicates that increased amorphous particula
te matter (indicating infection) might be one of the contributing factors t
o lower acridine orange stainability. Thus acridine orange staining can be
used to evaluate the integrity of the nucleus, disorders of which can cause
unexplained infertility or lower fertilization potential that may go undet
ected by routine analysis.