Abstract

Beta-2-microglubulin(beta 2m), the invariable light chain of the histocompatibility antigen is present on the surfaces of most human nucleated cells. It has proved to be reduced or disappeared on the cell surfaces of variable skin cancers. Patterns of beta 2m stainability in normal uterus and of the loss in several cervical epithelial lesions were examined by immunohistochemical staining using rat monoclonal and rabbit polyclonal anti-beta 2m, repectively on fresh tissues of 13 cases and formalin-fixed paraffin-embedded tissues of 23 cases. To know patterns of loss of beta 2m stainability and measure its extent and degree, only fixed tissues were examined. Fresh uterine tissue showed beta 2m stainability present on the cell membranes of squamous epithelium, endocervical gland, and capillary endothelium. Of these, squamous epithelium of uterine cervix revealed most characteristic lace-like staining along the cell outlines. Paraffin-embedded 23 cases were classified as group I (6 normal conrol and metaplasia), II (5 mild and moderate dysplasia), III (6 severe dysplasia and carcinome in situ), and IV ( 6 microinvasive and invasive squamous cell carcinoma). Group 2-4 showed reduced beta 2m stainability when compared to group 1 that exhibited the similar stainability as fresh normal cervical epithelium. The reduction or less proved to be statistically significant(p-value<0.001) in group 3 and 4 except for group 2. In spite of being invasive cases, a few disclosed beta 2m positive cells mainly in well-differentiated areas. In sum, ABC immunohistochemical staining of beta 2m showed the tendency tend to decrease or disappear in uterine cervical epithelial lesions with premalignant or malignant change and rather to appear in some well-differentiated areas of malignant lesions.

• Keywords: Beta-2-microglobulin;Immunohistochemical stain;Uterine cervix;Epithelial lesion;