Langerhans cells in squamous exocervical carcinoma: a quantitative and ultrastructural study

Immunohistochemical and ultrastructural study of Langerhans's cells in squamous cell carcinoma of the cervix

OBJECTIVE

To study Langerhans's cells (LCs) in cervical squamous cell carcinoma.

STUDY DESIGN

The study was carried out in the Shatby University Hospital, Alexandria, Egypt. Thirty cases with squamous cell carcinoma, 10 cases with cervical intra-epithelial neoplasia (CIN) and 10 cases with normal exocervix were recruited. Sections from the exocervix were stained with gold chloride, immunostaining with S-100 protein antiserum, adenosine triphosphatase ATPase and electron microscopy. Statistical evaluation was done using the t-test.

RESULTS

Gold chloride staining revealed significantly increased number of LCs in all cases of CIN compared to normal controls and with increasing grade of CIN (p < 0.001). No relationship between LCs number and the grade of carcinoma. Least branched LCs were predominant in the normal tissue while in neoplasia, these cells were of the most branched type, indicating a hyperactivity. S-100 protein positive LCs were almost absent in normal controls while their number were almost lower than the corresponding cases of CIN and invasive carcinoma after gold chloride or ATPase stainings. Signs of hyperactivity were evident in LCs of neoplastic cases after electron microscopy.

CONCLUSIONS

Proliferation and increased number of LCs in CIN is an immune response, while such reaction is suppressed by invasive carcinoma.

Lymphoepithelioma-like carcinoma of the skin

Lymphoepithelioma-like carcinoma of the skin is a rare tumor with a microscopic resemblance to lymphoepitheliomatous tumors of the nasopharynx. A 62-year-old woman exhibited such a tumor on the nose together with regional lymph node metastases. Histologically, irregular islands of atypical epithelial cells unconnected to the overlying epidermis were surrounded by or mixed with numerous lymphocytes in the primary tumor. No squamous or glandular differentiation was present. Metastases to the submandibular lymph nodes appeared as glassy squamous cells that resembled trichilemmal keratinization. Staining of the tumor tissues with S-100 protein antibody revealed the presence of numerous short dendritic cells in clusters of epithelial cells. Total resection and adjunctive radiotherapy have led to a 6-year period free of recurrence. This is the second case report of this condition in Japan.

Decreased immunologic responsiveness following intensified vaginal immunization against urinary tract infection

In an attempt to further increase the protective effect of vaginal immunization against urinary tract infections in Cynomolgus monkeys, the immunogen of killed E. coli was given more times, in larger amounts, and with the adjuvant MDP. Instead of increasing the protective effect, no protective effect on induced cystitis was observed. In addition, rises in urinary and serum immunoglobulins previously observed after vaginal immunization and induced cystitis were lessened. These observations appear to correspond with the classical concepts of immunologic unresponsiveness.

Langerhans cells of human mucosa

The ontogeny of human LC and their presence in all Malpighian epithelia underline their important role in immunoregulation of the skin and mucous membranes. LC are also found in buccal and esophageal mucosa, in cornea and conjunctiva, in pulmonary, vesical, vaginal and cervical epithelia as well as in placenta villi. In all these Malpighian epithelia, the presence of DR + LC is necessary and essential for the surveillance function against allergo-antigens and the emergence of neo-antigens associated with malignant transformations.

Ultrastructural characteristics of the contact zones between Langerhans cells and lymphocytes

The present work was carried out to look for the ultrastructural substrate of the contact zones between Langerhans cells and lymphocytes. A high resolution electron microscopic analysis of the contact zones between Langerhans cells and lymphocytes was performed. The material used for this study was obtained from experimental contact dermatitis in mice, and human cervical squamous carcinoma and mycosis fungoides. Three types of cell-cell binding were found. Type I is a junction-like structure characterized by the presence of intercellular bridges. It is suggested that this contact might represent a fixation mechanism between the two cells. Type II is characterized by a glycocalyx-glycocalyx continuity. An immunological function--recognition and antigen presentation--is proposed for this type of contact. Type III is a septilaminar tight contact area which seems to be a gap junction. It is suggested that all these types of physical contact might be the morphological expression of interaction between antigen presenting cells and lymphocytes.

Langerhans' cell density in the normal exocervical epithelium and in the cervical intraepithelial neoplasia

A morphometric analysis was performed of the Langerhans' cell density in epithelial sheets obtained from normal exocervices and from exocervices with squamous carcinoma. Laminae of exocervices with squamous carcinoma that showed cervical intraepithelial neoplasia (CIN) were classified according to its predominant degree of severity as CIN I, CIN II and CIN III or as normal when no neoplastic changes were found. Laminae with CIN showed a higher Langerhans' cell density than the laminae from normal exocervices and than the normal laminae of exocervices with carcinoma. The magnitude of the increase of Langerhans' cell density and the degree of severity of the neoplastic changes appear as closely related phenomena. An increase of the more ramified types of Langerhans' cell in the laminae containing CIN was found, with the most ramified being more frequent in the most severe lesions.

The widespread distribution of Langerhans cells in pathologic tissues: an ultrastructural and immunohistochemical study

Ultrastructural and/or immunohistochemical analysis of approximately 500 specimens revealed widespread distribution of Langerhans cells in pathologic specimens. More than half of the tissue specimens were from patients with a variety of pulmonary diseases. In all specimens in which Langerhans cells were identified ultrastructurally, they were also identified by an immunoperoxidase technique for the visualization of S-100 protein; the latter technique also revealed the dendritic nature of these cells. Langerhans cells were present in 80 to 93 per cent of 66 pulmonary adenocarcinomas and 17 per cent of squamous cell lung cancers; they were not observed in neuroendocrine lung carcinomas or mesotheliomas. They were also observed in benign inflammatory conditions of the lung of several types and in a variety of other malignant neoplasms and disease processes. The Langerhans cells in these tissues varied from few to many. They were most numerous in bronchioloalveolar cell carcinoma, sometimes appearing almost as frequently as tumor cells, and rare in some benign pulmonary conditions and other tumors. The function of Langerhans cells in these conditions is unknown, but they may have an immunologic function, such as antigen processing and presentation to T lymphocytes.

Quantitative assessment of Langerhans cells in actinic keratosis, Bowen's disease, keratoacanthoma, squamous cell carcinoma and basal cell carcinoma

The quantitative distribution of Langerhans cells (LC) was studied in a range of pre-neoplastic, in-situ and invasive neoplastic skin lesions using an antibody to S100 protein and the indirect immunoperoxidase technique. LC numbers were increased within the lesions of actinic keratosis, Bowen's disease, keratoacanthoma, squamous cell carcinoma and basal cell carcinoma. In all lesions except actinic keratosis the LC density was also significantly increased in the adjacent non-neoplastic epithelium. The increased LC density in neoplastic epithelium suggests either that LC are being retained within the abnormal epithelium for longer periods of time than normal or that increased numbers of LC are being actively attracted by factors produced by the neoplastic epithelium. While reduction of intraepithelial LC density may allow the initiation of neoplasia the increased density observed in this study suggests that at later stages of tumour growth LC may have a functional role in the host response to cutaneous neoplasia.

Quantitative assessment of Langerhans' cells in human cervical intraepithelial neoplasia and wart virus infection

Langerhans' cell density was assessed quantitatively in cervical wart virus infection (cervical condyloma), cervical intraepithelial neoplasia, and koilocytic dysplasia with use of an antibody to S100 protein and an indirect immunoperoxidase technique. When compared with normal ectocervix, Langerhans' cell density was significantly decreased in cervical wart virus infection and significantly increased in cervical intraepithelial neoplasia. In koilocytic dysplasia, intermediate Langerhans' cell densities were obtained. In addition to being increased within the lesions of cervical intraepithelial neoplasia, Langerhans' cell density was increased in the adjacent normal ectocervix. Human papillomavirus, by reducing intraepithelial Langerhans' cell density, may decrease local immune surveillance and thus have a promoter effect in the development of cervical cancer. Following the development of cervical intraepithelial neoplasia the increase in intraepithelial Langerhans' cell density suggests a specific immune response directed against neoantigens associated with malignant transformation. If a permissive wart virus infection persists after transformation to cervical intraepithelial neoplasia (koilocytic dysplasia), continued depletion of Langerhans' cells results in intermediate densities.