ZNF295-AS1 inhibits autophagy via the ZNF295-AS1/miR-508-5p/ATG7 axis in AS.

OBJECTIVE: As a result of gene-environment interactions, the incidence of atherosclerosis (AS) is rapidly increasing worldwide. Autophagy in endothelial cells is a key process of AS and is difficult to control when it becomes excessive in the end stage of AS. MATERIALS AND METHODS: In this study, we found increased expression levels of ZNF295-AS1 in the serum of AS patients, as well as in ox-LDL-treated HUVECs. The autophagy level was also upregulated in both samples. We demonstrated that ZNF295-AS1 may interact directly with miR-508-5p to act as a miR-508-5p sponge. The negative relationship between ZNF295-AS1 and miR-508-5p indicated that ZNF295-AS1 may be an upstream suppressor of miR-508-5p. RESULTS: ATG7 plays a critical role in autophagy and was predicted to be a target of miR-508-5p. Therefore, we overexpressed miR-508-5p, which reduced the expression level of ATG7, enhanced cell proliferation and prevented autophagy. These data indicated that the ZNF295-AS1/miR-508-5p/ATG7 axis may participate in autophagy regulation in ox-LDL-treated HUVECs. The subsequent rescue experiments revealed the specificity of the ZNF295-AS1/miR-508-5p/ATG7 axis in the contribution of ZNF295-AS1 to autophagy. CONCLUSIONS: Overall, our findings demonstrate a novel mechanism by which ZNF295-AS1 silencing regulates ATG7 reduction and inhibits autophagy, which may delay the progression of AS. The ZNF295-AS1/miR-508-5p/ATG7 axis may be of therapeutic significance in AS.

[Effects of Prrx2 gene silencing on the proliferation of breast cancer and its molecular mechanisms].

Objective: The aim of this study was to investigate the effects of silencing Paired related homoeobox 2 (Prrx2) expression on the proliferation of breast cancer and its molecular mechanisms. Methods: Short hairpin RNA knockdown of Prrx2 was used to examine cellular effects of Prrx2. The level of Prrx2 was verified by Western blot. MTT assay was used to analyze the proliferation of breast cancer cells in vitro. To investigate the effect of Prrx2 depletion on tumor growth in vivo, a nude mouse xenograft model was performed. Results: The expression of Prrx2 decreased 91.2% in MDA-MB-231 cells and 88.7% in MCF-7 cells after transfection with interfering vectors (P<0.05). MTT assay showed that the proliferation of cells in silenced Prrx2 expression group was significantly inhibited compared with the control group (P<0.05). Nude mice transplanted tumors showed that the growth of transplanted tumors was slow after silencing Prrx2 expression, and the weight of the tumors of silenced Prrx2 expression group were smaller than those of the control group ((160.2±26.3)mg vs (365.4±19.7)mg, P<0.05). Western blot showed that silencing Prrx2 expression inhibited the expression of ß-catenin in breast cancer cell nucleus and down-regulated the activity of Wnt/ß-catenin signaling pathway. Conclusions: Silencing Prrx2 expression can effectively inhibit the proliferation and growth of breast cancer, suggesting that Prrx2 may become a new target for the treatment of breast cancer.

[The influence factors of pathologic complete response of the ipsilateral supraclavicular lymph node of breast cancer after neoadjuvant chemotherapy].

Objective: To investigate the factors affecting the pathologic complete response (PCR) of the ipsilateral supraclavicular lymph node (ISLN) of breast cancer after neoadjuvant chemotherapy (NAC). Methods: A total of 178 patients with breast cancer who had primary ipsilateral supraclavicular lymph node metastasis (ISLNM), receiving NAC and subsequent ISLN dissection, were retrospectively reviewed. The single factor and multi factor analysis were carried out by the chi square test and the Logistic regression model. Results: The enrolled patients were all female, 28 to 74 years old. The rate of PCR on the ISLN was 52.2%. Single factor analysis showed that KI67 expression level (χ(2)=7.717,P=0.005), breast PCR (bPCR) (χ(2)=33.564,P<0.001), and axillary PCR (aPCR) (χ(2)=31.750, P<0.001) were associated with the ISLN PCR. Multifactor analysis showed that KI67 expression level (OR=4.096, 95%CI: 1.176-14.263, P=0.027), bPCR (OR=4.452, 95%CI: 1.894-10.461, P<0.001) and aPCR (OR=5.183, 95%CI: 1.974-13.605, P<0.001) were independent predictors of ISLN PCR. The rate of PCR on the ISLN was 90.9% in the patients with KI67>30% and simultaneous breast and axilla PCR. Conclusions: The PCR rate of the ISLN after neoadjuvant chemotherapy is higher than that of the breast and axillary PCR. The expression level of KI67, the bPCR and the aPCR are independent predictors of the PCR on the ISLN.

[Analysis of factors influencing the axillary lymph node metastasis and breast cancer-specific survival in patients with T1 breast cancer].

Objective: To investigate the predictors of axillary lymph node metastasis and the breast cancer-specific survival (BCSS) in patients with T1 breast cancer. Methods: A retrospective analysis of clinical and pathological data of 840 T1 invasive breast cancer cases between January 2009 and January 2014 in Henan Cancer Hospital was conducted.Chi square test and Logistic regression analysis were carried out to identify relevant factors of lymph node metastasis. Analysis of prognostic factors were analyzed by Log-rank test and Cox regression. Results: Among the 840 T1 breast cancer cases, positive axillary lymph nodes were found in 150 (17.9%) cases. Univariate analysis showed that tumor size, histological grade, tumor location, and HER2 status were associated with axillary lymph node status (P<0.05). Multivariate analysis showed that tumor size, histological grade, tumor location, and HER2 status were independent predictive factors of axillary lymph node metastasis (P<0.05). Log-rank test showed that tumor size, histological grade, HER2 status, partial response (PR) status and number of positive lymph nodes were important factors influencing BCSS of the patients with positive axillary lymph nodes (P<0.05). Cox analysis showed that the size of the primary tumors and the number of positive lymph nodes were independent factors affecting the BCSS of the patients(P<0.05). Conclusions: Tumor size, histological grade, tumor location and HER2 status correlated with axillary lymph nodes status of T1 breast cancer. For T1 breast cancer patients with positive axillary lymph node, more positive lymph nodes involved and smaller primary tumor correlated with worse prognosis.

[The influence of lumpectomy on the axillary lymph node status of breast cancer patients].

Objective: To investigate the influence of lumpectomy on axillary lymph node status of breast cancer patients. Methods: The clinical data of 738 invasive breast cancer patients with non-palpable axillary lymph node and sentinel lymph node (SLN) biopsy from November 2011 to August 2013 in Henan Provincial Cancer Hospital were collected and retrospectively analyzed. Among them, 136 patients underwent preoperative lumpectomy (lumpectomy group) and 602 patients underwent puncture biopsy only (biopsy group). The difference of axillary lymph node status and positive ratio of SLN detected by color Doppler ultrasound were compared between these two groups. Results: Among the 738 breast cancer patients, the axillary lymph nodes of 444 (60.2%) cases could be detected by ultrasound. Among them, 92 cases belonged to lumpectomy group, significantly less than 352 cases of biopsy group (P=0.048). Among the patients with ultrasound-visible lymph nodes, the proportion of the biggest diameter of axillary lymph node >1 cm of lumpectomy group or biopsy group was 58.7% (54/92) or 52.8% (186/352), respectively, without significant difference (P=0.316). The proportion of patients with the ratio of long diameter to short diameter <2 of lumpectomy group or biopsy group was 37.0% (34/92) or 38.6% (136/352), respectively, with marginal difference (P=0.768). The positive rate of SLN of lumpectomy group or biopsy group was 23.5% (32/136) or 26.9% (162/602), respectively, without significant difference (P=0.419). The incidence rate of the ultrasound visible axillary lymph nodes of patients whose postoperative time ≤ 7 days or > 7days was 71.1% (64/90) or 60.9% (8/46), respectively, without significant difference (P=0.227). However, the positive rate of SLN of these two groups was 28.9% (26/90) and 13.0% (6/46), respectively, with significant difference (P=0.039). The number of ultrasound visible axillary lymph nodes, the biggest diameter of axillary lymph nodes and the ratio of the long diameter to short diameter <2 were substantially correlated with the positive rate of SLN (P<0.05). Conclusions: The incidence rate of ultrasound visible axillary lymph node in the patients with lumpectomy is higher than that of patients with puncture biopsy only. The positive rate of SLN of the patients with a long postoperative time is lower than that of patients with a short postoperative time, even though the axillary lymph nodes are ultrasound visible.

[Analysis of predictive effect of Androgen receptor on the response to neoadjuvant chemotherapy in breast cancer patients].

Objective: To explore the expression of androgen receptor (AR) in the tissues as well as its association with the clinicopathological factors of primary breast cancer patients treated with neoadjuvant chemotherapy (NAC), and analyze the effect of AR in the prediction of pathologic complete response (PCR) rate. Method: A total of 668 breast cancer patients treated with NAC in Henan Cancer Hospital between March 2014 and June 2017 were retrospectively reviewed. The relationship of AR expression and clinicopathological characteristics was calculated using chi square test. Multivariate analysis using binary Logistic regression was used to analyze correlations of different factors with PCR. Result: All patients were female, with the age of 20-76 years old. AR was detected in 74.6% of tumors, and significantly correlated with hormone receptor (HR), human epidermalgrowth factor receptor-2 (HER-2), Ki-67, CK5/6, epidermal growth factor receptor (EGFR) and molecular subtypes (all P<0.05). Multivariate analysis showed that AR, HR and HER-2 were independent predictors for PCR (all P<0.05). Conclusions: The expressions of AR were more frequently in HR positive breast cancer tissues (86.7%), and lowest in triple-negative breast cancer (TNBC) group (23.2%). AR was independent predictor for PCR.

[DNA methylation modification of BRMS1 in triple-negative breast cancer and its correlation with tumor metastasis].

Objective: To investigate the effect of methylation status of breast cancer metastasis suppressor gene 1 (BRMS1) on the expression of breast cancer and the biological behavior of cancer cells in triple-negative breast cancer (TNBC). Methods: The expression of BRMS1 in TNBC tissues and corresponding non-malignant tissues and its relationship with clinicopathological parameters were detected by immunohistochemistry. The mRNA and protein expression of BRMS1 in normal breast epithelial cells and TNBC cells were detected by reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting. The methylation specific polymerase chain reaction (MSP) was used to detect the methylation status of BRMS1 in each cell. These cells were treated with demethylated preparations (5-Aza-dC) to re-activate BRMS1 expression. Using tumor cell invasion assay to detect influence of BRMS1 demethylation on the invasion capacity of cancer cells. The data were statistically analyzed. Results: The positive expression rate of BRMS1 protein in TNBC tissues was significantly lower than that in corresponding non-malignant tissues (χ(2)= 6.635, P<0.05). The mRNA expression level of BRMS1 in patients with lymph node metastasis was significantly lower than those with no lymph node metastasis (P=0.018). The down-regulation of BRMS1 expression was related to the methylation of DNA promoter, which was statistically significant (χ(2)=14.68, P<0.05). The mRNA and protein expression of BRMS1 was also correlated with tumor size and TNM staging (P=0.000-0.003). After using 5-Aza-dC, the number of cells with invasive capacity was significantly lower than those of the control group (t=3.262-10.72, P<0.05). Conclusions: The decrease of BRMS1 expression in TNBC cells is related to the methylation of DNA. Demethylation can inhibit the invasion of breast cancer cells.

Expression of CDCA8 correlates closely with FOXM1 in breast cancer: public microarray data analysis and immunohistochemical study.

Forkhead Box M1 (FOXM1) is an oncogenic transcription factor implicated in breast cancer progression and metastasis. However, the clinical significance of FOXM1 and its associated signaling genes in human breast cancer still needed to be clarified. In this study, we first analyzed the co-expression gene pattern of FOXM1 in three breast cancer gene expression microarray datasets from the Oncomine database. Cell division cycle associated 8 (CDCA8) gene was identified to correlate closely with FOXM1. In silico analysis further indicated that CDCA8 overexpressed in breast cancer tissues compared with the normal controls is significantly associated with the triple-negative phenotype. Experimentally, we performed a immunohistochemical study to detect the expression of CDCA8 in 112 breast cancer samples, and evaluated its clinicopathological and prognostic significance. We found that CDCA8 was frequently over-expressed in breast cancer tissues, and increased expression of CDCA8 was positively associated with FOXM1 expression, triple-negative phenotype and shorter overall survival. Moreover, we also found that combination of CDCA8 and FOXM1 showed a higher hazard ratio than the individual markers. Our results suggest that FOXM1-CDCA8 signature might be involved in breast cancer progression, and serves as a potential prognostic factor and a promising therapeutical target.

Effect of single-injection versus continuous local infiltration analgesia after total knee arthroplasty: a randomized, double-blind, placebo-controlled study.

In this randomized, double-blind, placebo-controlled, single-centre study, 80 patients (American Society of Anesthesiologists physical status I-III) received postoperative single-injection local infiltration analgesia (SLIA), continuous local infiltration analgesia (CLIA) or placebo (control group). Intravenous patient-controlled morphine was used as rescue analgesia. The CLIA group showed lower postoperative visual analogue scale (VAS) pain scores from 8 to 48 h at rest and from 16 to 48 h during activity compared with the SLIA group. The CLIA group also had significantly lower consumption of morphine from 24 to 48 h postoperatively versus the SLIA group. Patient satisfaction was higher, and maximum flexion of the knee on postoperative days 7 and 90 was greater, in the CLIA group compared with the SLIA group. CLIA provided prolonged superior analgesia and was associated with more favourable functional recovery and patient satisfaction compared with SLIA.

[Changes in cardiac contractility induced by stimulation of hypothalamic ventromedial nucleus].

Experiments were performed on anesthetized cats to observe the effect of electrical stimulation of the hypothalamic ventromedial nucleus (VMH) on cardiac contractility as judged by the change in LVSP, dp/dtmax, Vmax, P-dp/dt, P-lndp/dt. Electrical stimulation of VMH induced an augment response in cardiac force, while stimulation of an area between VMH and the third ventricle led only to a decrease in cardiac contractile force. All these changes were not accompanied by significant changes in heart rate and unaffected by bilateral vagotomy. The present experiment indicates that the inotropic and chronotropic regulation centers of cardiac function exist in different hypothalamic areas.

[Development of gentamicin sulfate sustained release tablet remaining-floating in stomach].

Gentamicin sulfate sustained-release tablet remaining-floating in stomach (G-HBS) was developed based on the hydrodynamically balanced system. The dissolution rate of G-HBS was determined by rotary basket method (100 r/min, 37 +/- 0.5 degrees C, 0.1 mol/L HCl). The release characteristics of G-HBS showed basically first order kinetics with the dissolution rate constant (Kr) of 0.3992 h-1. The mean dissolution time (MDT) of G-HBS was 2.53 h-1. The density of G-HBS was found to have no significant influence on dissolution of G-BHS. The gamma-scintiphoto technique was used to examine the gastric retention time of G-HBS and GCT (gentamicin sulfate conventional tablet). It was shown that the gastric retention time of all subjects taking G-HBS under fed and fasted conditions were all over 4 h, in contrast with GCT, only 1-2 h. The stability of G-HBS was investigated and a tentative two-year expiration date was established. Spectrophotometry for the determination of gentamicin was established. The effect of G-HBS on Campylobacter pyloridis-associated chronic gastritis was examined through clinical trials.

Adipose tissue islets: tissue culture of a potential source of fat cells in the adult rat.

Collagenase digests of adipose tissue of the 3 to 4-month-old rat contain groups of 20-100 tightly arranged cells (islets) that copurify with the free-floating fat cells. When cultured along with mature adipocytes the islets give rise to cells, initially fibroblast-like, which rapidly proliferate, acquire lipid droplets, and differentiate into small adipocytes within 4-6 days without the addition to the medium of the agents usually required to produce differentiation in stromal-vascular preadipocytes. Differentiation of these cells is independent of confluence and begins as early as day 2 of culture. The proportion of islet-derived cells that differentiate is directly correlated with the number of mature adipocytes simultaneously present in the culture (r = .709; P less than 0.001). Culture medium exposed to mature adipocytes demonstrated differentiation-promoting activity, suggesting a paracrine effect of these cells. Islets may in vivo constitute a source for newly formed adipocytes in the adult rat. The differentiation of these potential adipocytes may be regulated, at least in part, by the mature fat cells via a paracrine effect.

Preadipocyte stimulating factor in rat serum: evidence for a discrete 63 kDa protein that promotes cell differentiation of rat preadipocytes in primary cultures.

In primary cultures of rat preadipocytes (PA) isolated from epididymal or perirenal depots, rat serum is more effective than other animal sera (fetal calf, newborn calf, human, horse, rabbit, cat, sheep, goat, dog, pig) in promoting adipogenic conversion, biochemical differentiation, and mitogenesis. Only mouse serum is comparable to rat serum. This activity is attributable to a specific growth factor (preadipocyte stimulating factor, PSF). An assay for PSF in rat serum was devised using PA from perirenal fat of 3-month-old Fischer 344 rats grown first to confluence in FCS for 8 days and then for the next 3 days in test serum, followed by measurement of triglyceride (TG) and glycerol-3-phosphate dehydrogenase (GPDH). Rat serum induces dose-dependent rapid cell division, which coincides with accumulation of TG and increase of GPDH; for routine quantitation, TG is assayed. The biochemical characteristics of PSF in serum are as follows: stable at 4 degrees C for up to 1 year; inactivated at 100 degrees C (80% loss, 30 min) but stable at 56 degrees C for 1 hr; stable at pH 2-12; non-dialyzable; completely resistant to pepsin, trypsin, and chymotrypsin but destroyed by pronase and subtilisn; stable to DTT and periodate; and m.w. between 68 kDa (Sephacryl-300) and 58 kDa (Sephacryl-300 in 5 M urea). PSF activity is greater in serum from Wistar than from Fischer 344 rats, while activity of serum from Zucker obese (fa/fa) rats is at least as great as that from Wistar rats and, like serum of rats made obese by feeding a high-fat, high-carbohydrate diet, is not suppressed. PSF activity is not due to insulin, insulin-like growth factor-1 (IGF-1), growth hormone, glucocorticoids, or combinations of these hormones. PSF activity was not seen with a number of growth factors including colony-stimulating factor (CSF-1), GM-CSF, interleukins 1, 2, and 3, neuroleukin, tumor necrosis factor, and others. PSF is distinct from the low molecular weight (4-8 kDa) differentiation factor present in rat serum, FCS, and human serum that promotes the adipogenic conversion and cellular differentiation of 3T3-L1, 3T3-F442A, and Ob17 cells. PSF appears to be a new differentiation factor for rat preadipocytes, has properties suggestive of a highly glycosylated protein, and may be highly species specific.

[Age-dependent changes in the phosphorylation of nuclear phosphoproteins of rat salivary glands].

Development, growth, maturation and aging processes of secretory cells of rat salivary glands progress mainly after birth. Nuclear non-histone proteins, phosphorylated actively and reversively, have an important role as regulatory molecules of gene activity and have a possibility to bring about specific changes in these cellular processes. We examined in the present study the age-dependent changes in the phosphorylation of non-histone proteins of rat salivary glands. Nuclei purified from submandibular and parotid glands of 8-week-old rats rapidly incorporated 32P from gamma-32P-ATP into the nuclear phosphoproteins and reached equilibrium within 9 min. A preponderant amount of the 32P was present in non-histone proteins. The levels of phosphorylation of non-histone proteins in salivary gland nuclei increased rapidly after birth, reaching a maximum in both gland nuclei of 4-week-old rats and then decreasing to the levels observed in submandibular and parotid gland nuclei from 20 and 16-week-old rats, respectively. These levels were still maintained in nuclei from aged rats. Moreover, age-dependent changes in the protein kinase activity of submandibular and parotid gland nuclei were linked up with the changes in the phosphorylation of non-histone proteins. However, changes were not observed in the phosphorylation of histone proteins after birth. These results suggest that protein kinase activity in salivary gland nuclei may have an important role on age-dependent changes in cell function, mediated through the control of the phosphorylation of non-histone proteins.

Prostaglandin-sensitive adenylyl cyclase of cultured preadipocytes and mature adipocytes of the rat: probable role of Gi in determination of stimulatory or inhibitory action.

Preadipocytes of rats were obtained from the stromal-vascular fraction of collagenase-digested perirenal fat pads and grown in serum-containing medium. By day 8 of culture the cells reached confluence and by 12 days were lipid-laden. The adenylyl cyclase of the plasma membranes was compared to that of mature fat cells. Unlike the membranes from adipocytes, the preadipocytes showed adenylyl cyclase activity that was stimulated by GTP. Stimulation of preadipocyte membranes by Gpp(NH)p, NaF, and forskolin was comparable to that of membranes from adipocytes, but the response to epinephrine and isoproterenol was minimal (approximately 1.5-fold for preadipocytes vs. 4-5-fold for adipocytes). In contrast, GTP-dependent stimulation of adenylyl cyclase of preadipocytes by PGE1 was nearly 8-fold. Stimulation occurred even in the presence of both GTP and 140 mM NaCl, a condition that leads to inhibition by PGE1 of adenylyl cyclase in membranes of adipocytes. Other characteristics of the adenylyl cyclase of preadipocyte membranes that differ from those of adipocytes include lack of inhibition by GTP of forskolin-activated activity, and, following treatment with pertussis toxin, enhanced stimulation by PGE1. ADP-ribosylation of Gi and Gs with pertussis and cholera toxins, respectively, indicated that the membranes of preadipocytes contained only 5-11% of the Gi of adipocytes and a much lower ratio of Gi:Gs. These findings suggest that cultured preadipocytes have an incompletely developed Gi pathway that may account for the stimulatory effect of prostaglandins on the adenylyl cyclase of these cells as opposed to the inhibitory action of PG in mature fat cells.

Hormone-sensitive adenylyl cyclase in preadipocytes cultured from adipose tissue: comparison with 3T3-L1 cells and adipocytes.

The adenylyl cyclase system of preadipocytes derived from the stromal vascular fraction of perirenal rat fat pads was characterized. Unlike mature adipocytes, preadipocyte adenylyl cyclase was only weakly stimulated by catecholamines and adrenocorticotrophic hormone, but was stimulated by guanine nucleotides. Parathyroid hormone and 2-chloroadenosine also stimulated preadipocyte adenylyl cyclase. The adenylyl cyclase system of preadipocytes resembled that of undifferentiated 3T3-L1 cells. However, agents which induced the differentiation of the 3T3-L1 cell adenylyl cyclase system did not have a similar effect on preadipocytes. A medium (CDM6) which induced some differentiation of preadipocyte adenylyl cyclase was developed. The observations that the adenylyl cyclase system of preadipocytes and undifferentiated 3T3-L1 cells are similar, that preadipocyte adenylyl cyclase can be induced to develop along lines similar to early differentiation of 3T3-L1 cells, and that the adenylyl cyclase system of fully-differentiated 3T3-L1 cells has characteristics intermediate between preadipocytes and adipocytes, suggest that the differentiation of preadipocyte and 3T3-L1 adenyly cyclase in vitro mimics adipose adenylyl cyclase development in vivo. The increased catecholamine and ACTH stimulation, and reduced GTP and adenosine sensitivities of adipocytes compared to preadipocytes suggest that a number of genes affecting adenylyl cyclase-associated regulatory and receptor proteins are coordinately repressed and derepressed during development.

[Focal metastatic symptom as the initial presentation of lung cancer--report of two autopsied cases].

From 1956 to 1985, autopsy was done on 17 lung cancer patients in our hospital. There were two patients with focal metastasis as the presenting symptom without any primary cancer manifestations. One patient was admitted for severe right epigastric pain followed by severe pain in the left epigastrium. The chest film revealed nothing except some indefinite inflammatory lesions in the left upper lung. The patient died of uremia in 6 months. A primary carcinoma of 2 cm in diameter in the left lower lung was found on autopsy, which widely spread to the right lung, ovaries, upper segment of the left ureter, peribronchial and periaortic lymph nodes. Histological diagnosis was poorly differentiated adenocarcinoma. The other patient had destruction of the sphenoid bone with cranial nerve paralysis and hypothalamic syndrome at first. The primary cancer, a poorly differentiated adenocarcinoma of 2 X 3 X 1.5 cm in size, was found in the right upper lung on autopsy. Focal metastatic symptom as the initial presentation of lung cancer is rare. These tumors, as small lesions, frequently occur in the peripheral part of the lung. However, the site in which the presenting symptom develops may not necessarily be the place prone to metastasis. The presenting symptom, in turn, would depend upon the tendency of causing symptoms in the involved site. The author suggests that careful searching and identifying of the pulmonary lesion be routinely done for patients with metastatic carcinomatous symptoms only.

A highly sensitive assay method for human placental alkaline phosphatase involving a monoclonal antibody bound to a paper disk.

A monoclonal antibody which is specific for human placental alkaline phosphatase and does not cross-react at all with intestinal alkaline phosphatase was prepared, and a procedure for the determination of placental alkaline phosphatase activity in serum was developed involving this monoclonal antibody bound to a paper disk. The minimum amount of placental alkaline phosphatase detectable by this method is 0.0025 King-Armstrong unit. Good correlation with the heat-treatment method was obtained. Therefore this proposed method can be used as a routine clinical test for the determination of serum placental alkaline phosphatase.