Guide for antibody selection and antibody application in cancers (part six)

Posted by beauty33 on May 22nd, 2019

An overview of several commonly used antibodies for neurological and neuroendocrine tumors

1. Neuron-specific enolase (NSE)

It has been found that there are three kinds of the same enzymes in the brain tissue, namely dd.dr and rr. NSE belongs to the rr shape. It exists not only in nerve cells and their axons, but also in various endocrine cells and their associated tumor cells. Previous experiments detected 69 cases of APUD system tumors by NSE, and all of the results were positive; while only 2 of the 16 cases of secretory glands such as pancreatic cancer were positive. It can be seen that NSE is a very useful antibody for detecting tumors in the APUD system. It is suitable for a variety of tissue sections, with monoclonal and polyclonal antibodies, and better results can be obtained with antigen retrieval.

2. Chromogranin A

Chromogranin A antibody detects neuronal and neuroendocrine cells and its related tumors, such as pheochromocytoma, medullary thyroid carcinoma, islet cell tumor, pituitary tumor, carcinoid and so on. Monoclonal antibodies and polyclonal antibodies are available, which are suitable for various types of slices and antigen retrieval is required.

3. Glial fibrilary acidic protein (GFAP), clone 6F2

GFAP is one of the intermediate filament proteins and is an effective marker for astrocytes and ependymal cells and their derived tumors. According to the immunohistochemistry of 60 astrocytomas cases, the results were all positive. Therefore, it is the prior antibody choice for astrocytoma and ependymoma. Polyclonal antibodies have been used in the early stage, and monoclonal antibodies have been recently used, which do not require any treatment and are suitable for various sections.

4.S-100

S-100 is a protein isolated from bovine brain. Three sub-shapes of S-100 have been discovered through extensive research, i.e. S-100ao, S-100a and S-100b. It can be detected in human Schwann cells, ependymal cells, astrocytes, nerve fibers, nerve sheaths, skin melanocytes, and the like. Therefore, it can be used to detect tumors of the above tissues and their sources.

The antibody is suitable for various sections and does not require any treatment. The dilution should be 1:200 and the background should be controlled as much as possible.

Other antibodies for cancers

1. Thyroglobulin (TG), clone 2H11

TG is a glycoprotein synthesized by thyroid follicular cells. It is an antibody with high specificity among many antibodies. It is only used to detect thyroid tissue and tumors derived from it, without any treatment and good results can be obtained. It adapts to a variety of slices, but background control should be noted.

2. Bovine Dapiuomavirus (BPV)

The antibody is mainly used for detecting infectious diseases of the reproductive system such as condyloma acuminata. The virus is present in the hollowed cells of the epithelium. According to experiments, not all the hollow cells contain virus after color development detecting, which may be due to loss of cells on slices in the process of production. In the markers of 50 cases, viruses of varying contents were found. The antibody is a polyclonal antibody, and the dilution can be 1:400 when vacuum negative pressure detection is used. The background control should be noted, and good results can be obtained without any treatment, and are suitable for various slices.

3. Proliferation cell nuclear antigen (PCNA)

PCNA is an acidic protein with a molecular weight of 36 kD, which is an aid to DNA polymerase when DNA is replicated. This protein appears when the cell enters the proliferative cycle. It is a marker of the cell proliferation cycle, especially the "S" phase. Suitable for all kinds of slices.

4. Cow calf alkaline phosphatase (CAP)

The antibody detects normal osteoblasts, small intestinal cells, prostate epithelial cells, and cells containing CAP throughout the body. However, it is commonly used in clinical tests to detect the content of CAP in bone tumors and prostate tumors. The antibody does not require any treatment and is suitable for various sections.

5.Estrogen receptor (ER)

ER is an acidic protein with a specific function. It transmits hormone information. The study found that this substance is present in the nucleus of cancer cells, such as breast cancer, endometrial adenocarcinoma, cervical cancer and other cancer. At present, in the treatment of these cancer patients, it is first necessary to detect whether the ER is positive. If positive, anti-hormone therapy will be taken, if negative, hormone therapy will be taken. In conclusion, the positive or negative result of ER test is directly related to the choice of treatment plan, and is a hard indicator to judge the prognosis of patients. At present, when detecting ER, it is necessary to perform thorough and complete antigen retrieval. According to experiments, in order to obtain satisfactory results, it is necessary to perform long-time bath-type antigen retrieval, that is, immersing the slices in the container of the antigen repair solution, and then put it together in the pot and boil for forty minutes. If the antigen retrieval time is not enough, the slice can also be negative. In addition, high pressure retrieval, vacuum negative pressure and microwave retrieval can also be used.

6. Progesterone receptor (PR)

PR, like ER, is listed as a mandatory test in the treatment of breast cancer, cervical cancer, endometrial adenocarcinoma, etc. In order to develop a medical plan and judge the prognosis hard indicator, the general test is performed simultaneously with ER and PR.