Effects of recombinant follicle-stimulating hormone on bone turnover markers in infertile women undergoing in vitro fertilization procedure

CONTEXT

There is experimental but limited clinical evidence that FSH may have direct effects on bone.

OBJECTIVE

The aim of the study was to evaluate the effects of acute FSH stimulation on bone turnover in premenopausal women.

DESIGN AND SETTING

We conducted a prospective study at a referral center.

PATIENTS

Twenty-nine infertile women (age range, 30-40 yr) undergoing an in vitro fertilization procedure were included in the study.

INTERVENTIONS

Pharmacological suppression of endogenous gonadotropin and estradiol (E2) production by GnRH analog (leuprolide 1 mg/d s.c.) was followed by stimulation with recombinant FSH (rFSH; starting dose, 375 IU/d s.c.).

MAIN OUTCOME MEASURES

We measured serum osteocalcin, C-telopeptides of type-1 collagen (β-CTX), FSH, and E2 at the beginning of leuprolide administration (T0), at the beginning of rFSH administration (T1), and 3 d (T2) and 10 d (T3) after the first dose of rFSH.

RESULTS

At T1, the suppression of FSH and E2 secretion, as an effect of leuprolide administration, led to a significant increase in serum β-CTX values vs. T0 (P < 0.001). After the administration of rFSH, a rapid increase in serum FSH was observed, whereas serum E2 values increased more slowly. At T2, the increase in serum FSH values above our reference range for early follicular phase (with E2 in the reference range) did not induce any significant change in median serum β-CTX values as compared to T1. At T3 (when both FSH and E2 were high), serum β-CTX values decreased significantly vs. T1 (P < 0.001). Osteocalcin did not change significantly throughout the study period.

CONCLUSIONS

Our model suggests that FSH does not acutely exert relevant direct effects on bone metabolism in premenopausal women.

Serum leptin levels are higher in females affected by frontotemporal lobar degeneration than Alzheimer's disease

Frontotemporal lobar degeneration (FTLD) includes different heterogeneous conditions, mainly characterised by personality changes, along with cognitive deficits in language and executive functions. Movement disorders are variably represented. Behavioural disturbances constitute the core feature of FTLD, and eating disorders represent one of the most distinguishing symptoms between FTLD and Alzheimer's disease (AD). The biochemical correlates of such dysfunctions remain to be defined. The adipocyte derived hormone leptin is known to play a foundamental role in food intake and energy balance. To understand whether leptin could be involved in FTLD eating abnormalities, we measured serum leptin levels in 59 patients with FTLD compared with 25 with AD. Serum leptin levels in patients with FTLD were comparable with those in patients with AD. Nevertheless, females with FTLD showed significantly higher leptin levels compared with females with AD. No difference was found between FTDL and AD males or within the spectrum of patients with FTLD. Hyperphagic FTLD females showed higher circulating leptin levels in comparison with those without eating abnormalities; no differences were found between males with FTLD with respect to serum leptin and food intake disturbances. The present study showed a selective gender difference in leptin levels between females with FTLD and AD, which may suggest specific cognitive and behavioural networks need to be investigated.

Target-specific action of organochlorine compounds in reproductive and nonreproductive tissues of estrogen-reporter male mice

Organochlorines are lipophylic molecules that accumulate in the fat where they remain for years. During weight loss, they are mobilized and their concentration increases in blood. The present work tests, in transgenic estrogen-reporter mice (ERE-tK-LUC), whether this increase is sufficient to modulate the estrogen receptors (ERs) in the whole body. Three weak estrogens were studied: p,p'DDT [1,1,1-trichloro2,2-bis(p-chlorophenyl) ethane], p,p'DDE [1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene], and betaBHC [beta-benzene-hexachloride]. Dose-dependent analysis of reporter expression (luciferase) were performed in tissues of acutely treated mice. A body map of ER activation was obtained. All these chemicals modulated the reporter, although with a different efficiency and depending upon the tissue analyzed. Induction was confirmed in the liver by determining the expression of the endogenous progesterone receptor (PR) gene, at the dose and time point at which the luciferase gene was maximally induced. After experimental accumulation in the fat tissue, followed by a 48-h period of fasting, we tested whether these compounds could be mobilized to reach sufficient levels to activate the ERs in selected reproductive and nonreproductive tissues (testicle, prostate, liver, and lung). This experimental setting produced results that were different than those obtained following acute treatments. In loaded mice, fasting induced betaBHC mobilization resulted in strong ER activation in the liver and the lung, which was blocked by ICI-182780. p,p'DDT mobilization had no effect in these tissues, but it acted efficiently in the prostate and testis. betaBHC inhibited the ERE-mediated reporter in the testicle and induced the reporter in the prostate. In this tissue, betaBHC action was not inhibited by the anti-estrogen ICI-182780. During fasting, betaBHC, p,p'DDT, and metabolite p,p'DDE increased in blood concentration, from 2.25 +/- 0.25, 0.51 +/- 0.09, and 0.38 +/- 0.06 microg/ml to 8.24 +/- 0.95, 4.52 +/- 0.68, and 5.06 +/- 0.57 microg/ml, respectively. The effect produced by these organochlorines in the liver correlates with the modulation of the ERalpha protein. We conclude that these organochlorines modulate differently the expression of estrogen-regulated genes in male mice. Their effect is tissue- and compound-specific and is dependent on the energetic balance.

[Hypoparathyroidism following total thyroidectomy: prognostic value of intraoperative parathyroid hormone assay]

Transient and definitive hypoparathyroidism represent a frequent complication after thyroid surgery. Recently some authors proposed the use of intraoperative parathyroid hormone assay for the rapid detection of this complication. In this paper the authors describe the data obtained from 42 total thyroidectomies with intraoperative measurements of parathyroid hormone. When parathormone decrement was over 75% during thyroidectomy, the hypocalcemic symptomatology was found in all cases during postoperative observation. The authors emphasize intraoperative PTH dosage for immediate identification of patients at risk for postoperative hypoparathyroidism. In this cases parathyroid autotransplantation is suggested to prevent postoperative hypoparathyroidism.

Cardiovascular effects of a single slow release lanreotide injection in patients with acromegaly and left ventricular hypertrophy

In our study we assessed the effects of a single i.m. injection of slow-release Lanreotide (30 mg) (SR-L), a new long-acting somatostain analog, on circulating GH levels, baseline cardiac function (M-mode, 2D guided, doppler-echocardiographic study) and cardiopulmonary response to exercise (cycloergometric test, performed using a computer drived, electrically braked cycle ergometer), tested at baseline, after 7 and 14 days from the injection in 10 acromegalic patients (5 M, 5 F, mean age 57.7 +/- 3.1 yrs, body mass index (BMI) 27 +/- 0.8 kg/m2, blood pressure 141 +/- 6.5/82 +/- 3 mmHg). SR-L administration decreased GH levels in acromegalic patients (mean +/- SEM) from 16.1 +/- 6.9 to 10.8 +/- 5.1 micrograms/L (p = 0.045) after 7 days and to 11.9 +/- 5 micrograms/L (p = 0.078) after 14 days from the injection. Moreover, we observed a significant (p < 0.05) decrease in systolic blood pressure and heart rate at the 7th (135 +/- 6.1 vs 141 +/- 6.5 mmHg, and 68 +/- 2.1 vs 74 +/- 2.1 bpm) and 14th (137 +/- 6.2 vs 141 +/- 6.5 mmHg, and 72 +/- 2 vs 74 +/- 2.1 bpm) day of the study with respect to the baseline values. After SR-L administration we also found an increase in ejection fraction (69 +/- 2 vs 63 +/- 2.3% at 7th day, p = 0.006; 65 +/- 2.3 vs 63 +/- 2.3% at the 14th day, p = 0.027) and shortening fraction (40.8 +/- 1.8 vs 36.6 +/- 1.9% at 7th day, p = 0.005; 38.7 +/- 1.8 vs 36.6 +/- 1.9% at the 14th day, p = 0.045). The positive acute cardiac response to SR-L injection was also demonstrated by the increase in A/E velocity ratios at 7th (1.14 +/- 0.1 vs 0.98 +/- 0.07, p = 0.016) and 14th (1.04 +/- 0.08 vs 0.98 +/- 0.07, p = 0.008) day of the study. After SR-L injection, exercise capacity and VO2 at anaerobic threshold were also increased with respect to the baseline test: 61.1 +/- 8.2 vs 38.9 +/- 6.8 watts (p = 0.002) and 1012.4 +/- 71.5 vs 915.3 +/- 77.8 mL/min (p = 0.033) after 7 days, and 61.4 +/- 7.2 vs 38.9 +/- 6.8 watts (p = 0.002) and 1010.1 +/- 62.5 vs 915.3 +/- 77.8 mL/min (p = 0.010) after 14 days from the injection. In conclusion, these results suggest that in acromegalic patients: (1) SR-L causes a rapid improvement in baseline cardiac function and in cardiopulmonary performance during exercise in acromegaly; (2) the endocrine (decrease in GH levels) and echocardiographic responses to SR-L are maximal after 7 days from the injection, whereas the effect of SR-L on the exercise performance are longer lasting.

Comparison of finasteride versus flutamide in the treatment of hirsutism

OBJECTIVE

To compare the effectiveness of finasteride and flutamide in the treatment of hirsutism in patients with polycystic ovary syndrome (PCOS) and with idiopathic hirsutism.

DESIGN

Randomized study.

PATIENTS

One hundred and ten hirsute patients were selected: 64 women with PCOS and 46 with idiopathic hirsutism.

METHODS

Patients were assigned randomly to receive 5mg finasteride once daily or 250mg of flutamide twice daily, for 12 consecutive months. Hirsutism was evaluated at 12 months of therapy, with the Ferriman-Gallwey score and with measurement of the terminal hair diameters (microm) taken from four different body areas. Blood samples were taken for assessment of endocrine and hematochemical parameters. Side effects were monitored during the treatment.

RESULTS

Both finasteride and flutamide induced a significant decrease in the hirsutism scores and hair diameters at the end of 12 months. Finasteride reduced the Ferriman-Gallwey score by 31.4% in the PCOS cases and by 34.2% in the idiopathic hirsutism cases, and hair diameter by 27.0-34.1% in PCOS and by 29.6-37.9% in idiopathic hirsutism. Flutamide reduced the Ferriman-Gallwey score by 56.7% in PCOS and by 50.9% in idiopathic hirsutism, and hair diameter by 50. 3-60.0% in PCOS and by 47.7-56.5% in idiopathic hirsutism. Flutamide did not induce hormone variations, while finasteride increased testosterone levels by 40% in PCOS and by 60% in idiopathic hirsutism and decreased 3alpha-androstanediol glucuronide (3alpha-diolG) by 66.7% in PCOS and by 69.5% in idiopathic hirsutism. No important side effects or changes in the hematochemical parameters were observed with finasteride, while two patients (3.6%) in the flutamide group expressed abnormal transaminase levels after 6 months of treatment. Dry skin also appeared significantly more with flutamide (67.3%) than with finasteride (23.6%).

CONCLUSIONS

Both drugs are effective in the treatment of hirsutism but flutamide is more effective than finasteride.

Premature ovarian failure

Forty women with premature ovarian failure (POF) arising post-puberty (PPOF) during the reproductive lifespan, underwent karyotyping, pelvic ultrasonography, hormonal assays, hematochemical and immunological examinations. In 52.5%, PPOF was idiopathic, while in 45% the cause was immunological and in 2.5% chromosomal. The hormonal parameters were characterized by elevated plasma levels of gonadotropins (especially follicle-stimulating hormone, FSH), insulin and thyroid-stimulating hormone (TSH) and low levels of 17 beta-estradiol, prolactin, androstenedione, testosterone and dehydroepiandrosterone sulfate. One or more autoantibodies were present in 18 subjects (45%). Among the antibodies, the most representative were: antithyroid microsomal (27.5%), antinuclear antibody (20%) and antithyroid globulin (12.5%). Ultrasound showed that the ovaries were of normal volume (3.1 +/- 0.3 cm3) in 14 women (35%) and significantly smaller (1.4 +/- 0.4 cm3) in 26 (65%). Follicles were present in 10 women (25%). In patients with autoantibodies, ovaries were of small volume (n = 15, 83.3%) and had follicles (n = 6, 33.3%) in a significantly greater percentage compared to those without autoimmune etiology (n = 11, 50%; n = 4, 18.2%, respectively). Women with PPOF, all having secondary amenorrhea, presented significantly higher levels of total cholesterol, and low-density lipoproteins and lower levels of high-density lipoproteins.

Hypothalamic control of growth hormone (GH) secretion in type I diabetic men: effect of the combined administration of GH-releasing hormone and hexarelin, a novel GHRP-6 analog

Insulin dependent (type I) diabetic patients show abnormal growth hormone (GH) secretion. Hexarelin is an analog of GHRP-6 which releases GH in part via somatostatin inhibition. The aim of our study was to evaluate the effects of hexarelin and GHRH, administered either alone or in combination, on GH secretion in 10 type I diabetic and 7 normal men. All the subjects were administered: 1) human GHRH (1-29) NH2 100 micrograms i.v. bolus at 0 min; 2) hexarelin 100 micrograms i.v. bolus at 0 min; 3) hexarelin 100 micrograms + hGHRH 100 micrograms i.v. bolus at 0 min. In type I diabetic patients significantly greater GH responses to GHRH and hexarelin have been observed with normal subjects. Hexarelin caused a significantly (p < 0.05) greater GH response as compared to GHRH in both diabetic and control subjects. After the administration of hexarelin+GHRH, a significant increase in both GH absolute and peak levels as compared to hexarelin or GHRH alone was found in all the subjects. However, the GH responses to the combined stimuli were not significantly different in diabetics as compared to normals; moreover, the interaction of GHRH and hexarelin was synergistic in controls and additive in diabetics. We hypothesize that a reduction in the hypothalamic somatostatin inhibitory tone combined with increased pituitary GH production may be responsible for the pattern of the GH responses to hexarelin and GHRH observed in our type I diabetic patients.

Role of galanin in the regulation of somatotrope and gonadotrope function in young ovulatory women

The aim of the study was to elucidate the role of the neuropeptide galanin in the regulation of somatotropic and gonadotropic function in normal women. Thirteen normally ovulating (aged 28 to 40 years), non-obese (body mass index, 18.4 to 27.1 kg/m2) women with infertility due to a tubal or male factor were studied. Each woman underwent three tests: (1) bolus intravenous (IV) injection of growth hormone (GH)-releasing hormone (GHRH) (1-29)NH2 1 microgram/kg plus gonadotropin-releasing hormone (GnRH) 100 micrograms at time 0; (2) IV infusion of porcine galanin 500 micrograms in 100 mL saline from -10 minutes; and (3) bolus IV injection of GHRH(1-29)NH2 1 microgram/kg plus GnRH 100 micrograms at time 0 plus IV infusion of porcine galanin 500 micrograms in 100 mL saline from -10 to +30 minutes. All results are expressed as the mean +/- SEM. GH peak after GHRH was 14 +/- 5 micrograms/L; porcine galanin significantly increased serum GH (GH peak, 7.3 +/- 1.2) with respect to baseline levels. No significant differences were observed between either GH peak or GH absolute values after galanin as compared with GHRH alone. Porcine galanin significantly enhanced GH response to GHRH (peak, 31.4 +/- 4.4 micrograms/L) with respect to either GHRH or galanin alone. Luteinizing hormone (LH)/follicle-stimulating hormone (FSH) peaks after GnRH were 16.5 +/- 5.3 and 17.4 +/- 4 IU/L, respectively. Porcine galanin did not cause significant increases in serum LH and FSH levels with respect to baseline.(ABSTRACT TRUNCATED AT 250 WORDS)

Hexarelin, a novel GHRP-6 analog, counteracts the inhibitory effect of hydrocortisone on growth hormone secretion in acromegaly

Hexarelin (His-D-2-Methyl-Trp-Ala-Trp-D-Phe-Lys-NH2) is a GHRP-6 analog with the substitution of D-tryptophan with its 2-methyl derivative. The aim of our study was to ascertain whether hexarelin was able to counteract the glucocorticoid-mediated increase in hypothalamic somatostatin tone and consequent inhibition on serum GH levels in acromegalic patients. Ten patients (5 males, 5 females; age range 27-71 years; BMI range 23.3-35 kg/m2) with active acromegaly underwent: 1) hydrocortisone alone: a bolus iv injection of 100 mg hydrocortisone succinate in 2 mL saline, at time -60 followed by a 120 min iv infusion of 250 mg hydrocortisone succinate in 250 mL saline, from -60 to 60 min; 2) hexarelin+hydrocortisone: a bolus iv injection of hexarelin 100 micrograms, 60 min after initiation of a 2-hour hydrocortisone infusion; 3) hexarelin alone: a bolus iv injection of hexarelin at time 0, 60 min after initiation of a 2-hour saline infusion. The mean GH peak, expressed as percent change with respect to baseline level (mean of -75 and -60 minute samples), after hexarelin (1750 +/- 1157%) did not differ significantly with respect to that observed after hexarelin+hydrocortisone (1120 +/- 770%). After hydrocortisone alone the patients showed a mean decrease in GH levels as compared to baseline levels, of 47 +/- 7%. Our data show that the GH response to hexarelin in acromegaly is resistant to the inhibitor action of an acute and sustained elevation of serum cortisol levels. That hexarelin counteracts the glucocorticoid-mediated inhibition of GH secretion supports the hypothesis of an hexarelin-induced decrease in endogenous somatostatin tone.

Characterization of the paradoxical growth hormone inhibitory effect of galanin in acromegaly

Galanin is a 29-amino acid straight-chain biologically active peptide which has been found to decrease circulating GH levels in some acromegalic patients, whereas is able to increase GH secretion in normal subjects. The aim of our study was to ascertain the incidence, entity and mechanism of the paradoxical GH inhibitory effect of galanin in acromegaly also looking at possible correlations between the GH responses to galanin and the main clinical and biochemical features of the patients. Finally, the effects of either successful or unsuccessful neurosurgical intervention on the GH inhibitory effect of galanin in acromegaly were investigated. A series of 23 consecutive patients with active acromegaly seen at the Endocrine Section of the Department of Internal Medicine of the University of Brescia (Italy) between 1991 and 1994 was examined. The acromegalic patients were subdivided in group 1 (i.e. patients who were 1) untreated, 2) evaluated before surgery, and 3) not cured after surgery and radiotherapy) and group 2 (i.e. surgically cured). All patients were submitted at least once to the following biochemical and radiological evaluations: 1) baseline serum insulin-like growth factor-I and PRL samples, 2) iv infusion of synthetic porcine galanin (500 micrograms in 100 mL saline) from -10 to 30 min, 3) iv bolus injection of TRH (200 micrograms) at time zero, 4) oral glucose tolerance test (75 g glucose, orally) at time zero, and 5) magnetic resonance of the pituitary sella. Adenomatous tissue obtained during neurosurgery in four patients was cultured in vitro, and the effect of the addition of galanin in the culture medium on GH secretion was tested. During galanin infusion in 19 of 21 group 1 patients, serum GH levels were lower with respect to baseline (range of GH decrease, -6.2 to -85.4% with respect to basal levels). During galanin infusion, no reductions in GH levels were observed in the acromegalic patients cured after neurosurgery (group 2); on the contrary, 6 of 7 patients displayed a normal stimulatory response to galanin (range of GH increase, +120-1533.3% of the basal level). A significant correlation between the percent decrease in GH levels after galanin treatment and the percent increase after TRH was found in group 1 patients (r = -0.783; P < 0.05). In three of the four adenomas examined, galanin determined a clear decrease in GH secretion (mean nadir, 63.3 +/- 12% of the baseline secretion rate). In conclusion, we demonstrated that the large majority of numerous patients with active acromegaly show a decrease in serum GH levels after galanin administration.(ABSTRACT TRUNCATED AT 400 WORDS)

Immune response to opiates: new findings in heroin addicts investigated by means of an original enzyme immunoassay and morphine determination in hair

In the early 1970's, some papers appeared reporting an immune response to opiates in animals treated with morphine and in heroin addicts, but further researches failed to confirm these results in humans. The aim of the present work is investigating with a newly developed enzyme immunoassay the existence of specific antibodies to morphine in a group of opiate chronic users, controlled by means of the toxicological analysis of hair. Twenty five opiate addicts inpatients for detoxication treatments were investigated for the presence of morphine specific antibodies and for the morphine content in hair, as a marker of addiction to opiates. Antibodies to morphine were investigated using an original ELISA method using a morphine-human serum albumin conjugate immobilized into the wells of polystyrene microtiter plates. Morphine determinations in hair were accomplished by a radioimmunologic screening followed by HPLC confirmation of positive results. The group of opiate users, in which all the subjects resulted positive for morphine content in hair, showed in the ELISA test an average D OD% value significantly higher than the control group (p < 0.001); in particular, 16 out of 25 addicts could be classified positive for anti-morphine antibodies, which were identified as IgM. Inhibition studies demonstrated Ka's for morphine ranging from 10(4) to 10(10) M-1 and a high cross reactivity for codeine. The presence of circulating antibodies specific to morphine in chronic users of opiates is strongly supported by the present findings.

Antibodies for denatured human H-ferritin stain only reticuloendothelial cells within the bone marrow

Human H-ferritin homopolymer was denatured in sodium dodecyl sulphate and injected in mice to obtain antibodies for dissociated H-subunit. The antisera and Moabs obtained were specific for the denatured H-chain with no cross-reactivity with assembled ferritins in immunoblotting experiments. In contrast the Moabs for native recombinant H-ferritin are specific for the assembled ferritin molecules with weak cross-reactivity with the denatured H-subunits. The epitope recognized by one of the anti-denatured H-chain Moabs was mapped on the C-terminal helix of ferritin. The antibodies were used to study H-ferritin conformation in cells. In immunocytochemistry experiments the antibodies for denatured H-ferritin stained HeLa and K562 cells weakly, with a different intensity and pattern to those obtained with anti-native H-ferritin antibody. In human bone marrow smears the anti-denatured ferritin antibodies stained only reticuloendothelial cells, and did not recognize the H-ferritin rich immature erythroblasts. It is concluded that assembled and denatured H-ferritins are immunogenically distinct, and that erythroid and reticuloendothelial cells within the bone marrow contain H-ferritin in different conformations.

Quantitative immunoenzymatic assay of human lutropin, with use of a bi-specific monoclonal antibody

In this immunoenzymatic assay for human lutropin (hLH) we used bi-specific antibodies (BiAbs) obtained from the fusion of two hybridomas producing antibodies to beta-D-galactosidase and hLh. The BiAb complexed with the enzyme beta-D-galactosidase was used as tracer in a double-determinant assay. We compared the assay involving the BiAb (Bi-EIA) with an immunoenzymatic assay (EIA) in which the same capture antibody was used but the tracer was an enzyme-conjugated hLH-specific monoclonal antibody produced by the same parental cell line used to produce the BiAb. The coefficient of correlation (r) between the two assays was 0.979 but the Bi-EIA was more sensitive (detection limits: 0.8 int. units/L for the Bi-EIA, 2.0 int. units/L for the EIA) and more specific (less than 0.04% vs less than 1.2% cross-reactions with human choriogonadotropin). Mean intra- and interassay CVs for the Bi-EIA were 2.9% and 5.9%, respectively. Correlation (r) with an immunoradiometric assay (IRMA, Serono kit) was 0.960, with radioimmunoassay (RIA, Biodata kit) 0.909, and with an enzyme-linked immunosorbent assay (ELISA kit, Specialty Medical Industries Inc.) 0.888, (n = 25). Evidently, bi-specific antibodies can be used successfully in immunoenzymatic assays, and with potentially greater sensitivity and specificity than assay with a traditional antibody-enzyme conjugate.

Quantitative immunoenzymatic assay of human lutropin, with use of a bi-specific monoclonal antibody

In this immunoenzymatic assay for human lutropin (hLH) we used bi-specific antibodies (BiAbs) obtained from the fusion of two hybridomas producing antibodies to beta-D-galactosidase and hLh. The BiAb complexed with the enzyme beta-D-galactosidase was used as tracer in a double-determinant assay. We compared the assay involving the BiAb (Bi-EIA) with an immunoenzymatic assay (EIA) in which the same capture antibody was used but the tracer was an enzyme-conjugated hLH-specific monoclonal antibody produced by the same parental cell line used to produce the BiAb. The coefficient of correlation (r) between the two assays was 0.979 but the Bi-EIA was more sensitive (detection limits: 0.8 int. units/L for the Bi-EIA, 2.0 int. units/L for the EIA) and more specific (less than 0.04% vs less than 1.2% cross-reactions with human choriogonadotropin). Mean intra- and interassay CVs for the Bi-EIA were 2.9% and 5.9%, respectively. Correlation (r) with an immunoradiometric assay (IRMA, Serono kit) was 0.960, with radioimmunoassay (RIA, Biodata kit) 0.909, and with an enzyme-linked immunosorbent assay (ELISA kit, Specialty Medical Industries Inc.) 0.888, (n = 25). Evidently, bi-specific antibodies can be used successfully in immunoenzymatic assays, and with potentially greater sensitivity and specificity than assay with a traditional antibody-enzyme conjugate.