1 Chapter 8 Pregnancy Test Bence-Jones Proteins 17-Keto-Sterods Professor A. S. Alhomida Disclaimer The texts, tables, figures and images contained in this course presentation (BCH 376) are not my own, they can be found on: References supplied Atlases or The web King Saud University College of Science Department of Biochemistry

2 Relative Size of Human Conceptus

3 Maternal Fetal System Placenta 1.Connects Fetus and Mother 2.Transports:  Nutrients & O 2  Waste products & CO 2 away from fetus. 3.Early Nutrition of Fetus Due to:  Trophoblastic digestion  Absorption of nutrients from endometrial deciduas

4 Gestational Hormones 1.Human chorionicgonadotr opin (hCG) 2.Human chorionicsomatom ammotropin (hCS; hPL) 3.Estrogens 4.Progesterone Ovulation Parturition

5 Gestational Hormones, Cont’d

6 Human Chorionic Gonadotrophin (hCG) SecretionSecretion 1.It is a glycoprotein hormone produced by the developing placenta shortly after fertilization and the embryo attaches to the uterine lining and 2.It builds up rapidly in pregnant body in the first few days of pregnancy FunctionFunction 1.Prevent involution 2.Stimulate progesterone and estrogen secretion 3.Prevent menstruation 4.Promote endometrium growth 5.Stimulate testosterone Production  development of fetus male sex organs

7 Placental Estrogen SecretionSecretion 1.Secreted by placental trophoblast 2.Androgen precursors from maternal and fetal adrenal glands FunctionFunction 1.Uterus enlargement 2.Relaxation of pelvic ligaments – more limber for passage of fetus through birth canal 3.Breast enlargement 4.Growth of breast ductal tissue

8 Progesterone SecretionSecretion 1.Secreted by corpus luteum and placenta 2.Essential for pregnancy FunctionFunction 1.Development of decidual cells in endometrium for fetal nutrition 2.Decrease contractility of uterus 3.Prevent spontaneous abortions 4.Ovum development prior to implantation 5.Breast preparation for lactation

9 FunctionFunction 1.It is a general metabolic hormone 2.Partial development of maternal breasts 3.Effect on metabolism Decreases maternal glucose usage  for fetal usage Promotes FFA release from maternal stores  energy for fetus Weak action on protein deposition; similar to GH 4.It is important for the nutrition of mother and fetus Human Chorionic Somatomammotropin (hCS)

10 Clinical and Biochemical Significance of hCG 1.Increased urinary excretion of hCG which occurs in early pregnancy (early as 10 th day of gestation) 2.There are two different pregnancy tests: Biological Test (Aschein-Zondek test) has been replaced completely by: Immunological Test (home pregnancy test)

11 Home Pregnancy Test 1.It is a colloidal gold/antibody complex based rapid chromatographic immunoassay for the detection of hCG in urine 2.hCG can be detected in urine as early as 7 days after conception 3.hCG concentrations peak at about 9-12 weeks into pregnancy 4.The amount of hCG will vary greatly with gestational age and between individuals 5. It detects the presences of hCG in urine specimen at the sensitivity of low concentration

12 1.The hCG Urine dipstick Test consists of a chromatographic absorbent device and an unique combination of monoclonal antibodies that selectively detect hCG in test samples with a high degree of sensitivity 2.Urine migrates through the absorbent area and along the test membrane 3.hCG present in the specimen is bound by antibody-gold conjugate forming an antibody-antigen complex 4.The complex is captured by anti-hCG antibody immobilized in the test zone (T) of the membrane forming a pink-rose band Principle of Home Pregnancy Test

13 5.In the absence of hCG, no line will form in the test zone (T) 6.While the test line indicates the level of hCG present in the sample 7.Another gold conjugate is captured by the antibody immobilized in the control zone (C) of the membrane producing pink-rose color band, regardless of the presence or absence of hCG in the sample Principle of Home Pregnancy Test, Cont’d

14 Principle of Home Pregnancy Test CC: Control zone containing anti- hCG antibody to give pick-rose band TT: Test zone containing antibody-gold conjugate forming an antibody-antigen complex with urine hCG to form pick-rose band Negative ResultNegative Result: only one pick- rose band in C zone will appear Positive result: two pick-rose bands will form, one on C and other is on T zone

15 Home Pregnancy Tests, Cont’d

16 Home Pregnancy Tests, Cont’d

17 Bence-Jones Proteins 1.They represent either the kappa or lambda immunoglobulin light chains 2.They are most often associated with multiple myeloma (plasma cell cancer) 3.L chains are over produced by proliferating plasma cells and released into the blood without combining with H chains

18 Bence-Jones Proteins, Cont’d 4.They excreted in urine because of their relatively small size 5.They are precipitated at 60 C and used for diagnosing multiple myeloma 6.Excretion of BJ proteins in large amounts causes the tubular cells to become degenerated because of high levels of BJ reabsorbed

19 They comprise a group of steroid compounds which have a ketone at position Ketosteroids

20 17-Ketosteroids, Cont’d Assay for detection of 17-ketosteroid compounds

21 17-Ketosteroids, Cont’d

22 THE END Any questions?