| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
From the * Division of Urology and Department of
Surgery, St John's Mercy Medical Center, St Louis, Missouri; the
Division of Urology, St Louis University, St
Louis, Missouri; the Division of Urology,
Oregon Health Sciences University, Portland, Oregon; and the
St Louis University, St Louis, Missouri.
| Correspondence to: Dr Micheal J. Chehval, Division of Urology, St John's Mercy Medical Center, 615 S New Ballas Rd, St Louis, Mo 63141-8277 (e-mail: chehmj{at}stlo.smhs.com). |
| Received for publication October 10, 2001; accepted for publication April 12, 2002. |
 |
Abstract |
|---|
 Top Abstract Materials and MethodsResultsDiscussionReferences |
|---|
Key words: Autoimmune response, vasectomy, testicular damage, immunologic infertility
The effect of contralateral testicular damage after unilateral vas ligation has been demonstrated to be mediated through antisperm autoantibodies in several studies (Haas, 1987; Pedersen et al, 1987; Flickinger et al, 1988; Chehval et al, 1995). It has been reported that early repair of the severed vas, before the development of antisperm autoantibodies, will avoid potential damage to the contralateral testicle (Flickinger et al, 2000). In the present study, we have addressed the timing of antisperm antibody production, and we attempt to determine whether the onset of antibody production precedes histologic testicular damage.
|
Materials and Methods |
|---|
|
TopAbstractMaterials and MethodsResultsDiscussionReferences |
|---|
Group I— Five rats were used as the control group. On day 0, they were given halothane anesthesia, but no operative procedure was performed. On day 30, the animals were euthanized, blood was drawn, and testicles were harvested for histologic examination.
Group II— Five rats served as a sham control. On day 0, under halothane anesthesia, the left vas deferens was exposed but not divided. On day 30, they were euthanized, blood was drawn for antibody studies, and testicles were harvested for histologic examination.
Group III— Ten rats, on day 0, under halothane anesthetic, underwent a left vasectomy. On day 1, the animals were euthanized, blood was drawn, and testicles were harvested for histologic examination.
Group IV— Ten rats, on day 0, under halothane anesthetic, had a left vasectomy accomplished. On day 7, the animals were euthanized, blood was drawn, and testicles were harvested for histologic examination.
Group V— Ten rats, on day 0, under halothane anesthetic, had a left vasectomy performed, as above. On day 15, the animals were euthanized, blood was drawn, and testicles were harvested for histologic examination.
Group VI— Ten rats, on day 0, under halothane anesthetic, underwent a left vasectomy. On day 30, the animals were euthanized, blood was drawn, and testicles were harvested for histologic examination.
Histologic Examination
Testicles were fixed in Bouin solution and embedded in paraffin. Tissue
sections were stained with hematoxylin and eosin and examined by a single
examiner, blinded to the coding of the specimens' origin. The testicles were
evaluated histologically with respect to the following characteristics: 1)
seminiferous tubular diameter (measured with a calibrated ocular micrometer);
2) morphology and progression of maturation of the germinal epithelium; and 3)
morphology of the tunica propria and interstitial components, specifically to
determine whether fibrosis, hyalinization, or an inflammatory infiltrate could
be identified. When abnormalities were recognized, they were graded
"rare" (confined only to isolated tubules), "focal"
(confined to a discrete field and in more than 1 tubule), or
"diffuse" (present in all tubules uniformly).
Immunologic Assays
Serum was withdrawn from the blood samples and immediately frozen at
-70°C. The specimens, labeled with a random 2-letter code, were shipped in
dry ice overnight to Oregon Health Sciences University, in Portland, Ore, and
antisperm antibody levels were determined by an immunobead assay. This test
was accomplished by adding 1 mL of test serum to a test tube with 0.3 mL of
medium 199. To this suspension, 0.5 mL of purified rat sperm was added. The
mixture was incubated at 37°C for 30 minutes. After incubation, 10 µL
of serum/sperm suspension was mixed with 10 µL of goat anti-rat IgG-coated
Sepharose beads (Zymed Laboratories, South San Francisco, Calif). The density
of bound antibodies was approximated by counting the number of motile sperm
bound per bead under the microscope at high power. This test was repeated for
each specimen, and the 2 results were averaged.
Statistical analyses were performed by the Division of Biostatistics, Washington University School of Medicine, and are shown in Tables 1 and 2.
|
|
|
Results |
|---|
|
TopAbstractMaterials and MethodsResultsDiscussionReferences |
|---|
|
|
Immunologic Evaluation
There was no statistically significant difference comparing groups I and II
(the control animals) to the following: group III (animals euthanized at 1
day), P equals .21; group IV (animals euthanized at 7 days),
P equals .50; or group V (animals euthanized at 15 days), P
equals .44. There was, however, a statistically significant increase in
immunobead antibody binding in group VI (animals euthanized at 30 days),
P equals .02. These results are depicted in
Table 1 (mean percentage
binding) and Table 2 (percentage binding categorized as either a normal or positive result).
Antibody binding was assessed by a single investigator at the Oregon Health Sciences University who was blinded as to the coding of the specimens' origin. In that laboratory, greater than 40% binding is considered a positive result. When comparing the groups as to the number of animals with greater than 40% binding as a positive result and less than 40% as normal, the evaluation was as follows: comparing groups I and II, the controls, there was no difference compared to group III (animals euthanized at 1 day) P equals .35; group IV (animals euthanized at 7 days) P equals 1.00; or group V (animals euthanized at 15 days), P equals 1.00. There was a statistically significant difference between the control group and group VI (animals euthanized at 30 days), P equals .03.
No correlation, either positive or negative, between the presence of testicular abnormalities and immunobead binding assays was evident in individual animals.
|
Discussion |
|---|
|
TopAbstractMaterials and MethodsResultsDiscussionReferences |
|---|
In this study, the immunobead assay we used did not detect significant levels of antisperm antibodies until after 15 days. Other studies have shown a response as early as 1 week after bilateral vasectomy in the Lewis rat model using the enzyme-linked immunosorbent assay method (Herr et al, 1987). It is unclear whether the cause for these differing results can be attributed to the experimental design (ie, unilateral vs bilateral vasectomy) or to the sensitivity of the assay method itself. When the immunologic results are examined in conjunction with the histologic data, they appear to indicate that the onset of the antibody response precedes any demonstrable histologic damage to the testicle. There was no statistically significant histologic difference between any of the groups, while at the same time, there was a significant difference in immunobead antibody binding in the 30-day group (P = .02).
The relationship between immunologic response, specific sperm antigens, and infertility has yet to be clarified in humans, but experiments in the rat model may help us better understand immunologic infertility in men. It may be possible to infer that human antisperm antibody production will also precede histologic testicular damage, and further, that the development of human antisperm antibodies may take weeks. In cases of suspected or known ductal injury, the monitoring of antisperm antibody levels could possibly enable testicular damage to be predicted prior to its development and thus be avoided.
|
References |
|---|
|
TopAbstractMaterials and MethodsResultsDiscussionReferences |
|---|
Chehval MJ, Martin SA, Alexander NJ, Winkelmann T. The effect of unilateral injury to the vas deferens on the contralateral testis in immature and adult rats. J Urol.1995; 153:1313 -1315.[Medline]
Flickinger CJ, Howards SS, Carey PO, Spell DR, Kendrick SJ, Caloras D, Gallien TN, Herr JC. Testicular alterations are linked to the presence of elevated antisperm antibodies in Sprague-Dawley rats after vasectomy and vasovasostomy. J Urol.1988; 140:627 .[Medline]
Flickinger CJ, Vagnetti M, Howards SS, Herr JC. Antisperm autoantibody response is reduced by early repair of a severed vas deferens in the juvenile rat. Fertil Steril.2000; 73:229 -237.[Medline]
Haas GG. Antibody-mediated causes of male infertility. Urol Clin North Am.1987; 14:539 .[Medline]
Herr JC, Flickinger CJ, Howards SS, Yarbro ES, Spell DR, Caloras D,
Gallien TN. Temporal appearance of antisperm autoantibodies in Lewis rats
following vasectomy. J Androl.1987; 8:253
-258.
Lynn HB, Johnson WW. Inguinal herniorrhaphy in children. A critical analysis of 1,000 cases. Arch Surg.1961; 83:573 -579.
Matsuda T, Horii Y, Yoshida O. Unilateral obstruction of the vas deferens caused by childhood inguinal herniorrhaphy in male infertility patients. Fertil Steril.1992; 58:609 -613.[Medline]
Pedersen T, Rubenson A, Nilsson LA. Occurrence of sperm antibodies in adult rats after pre-fertile traumatic vas lesions. Scand J Urol Nephrol. 1987;21:1 -4.[Medline]
Shandling B, Janik TS. The vulnerability of the vas deferens. J Pediatr Surg.1981; 16:461 .[Medline]
Sparkman RS. Bilateral exploration in inguinal hernia in juvenile patients. Pediatr Surg.1962; 51:393 .
West D, Chehval MJ, Winkelmann T, Martin SA. Effect of vasovasostomy on contralateral testicular damage associated with unilateral vasectomy in mature and immature Lewis rats. Fertil Steril. 2000;73:238 -241.[Medline]
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
