Localization of T-lymphocyte areas in human lymphoid tissues by fluorochrome-labelled Helix pomatia A haemagglutinin

Immunofluorescent assessment of tumour infiltrating cells in laryngeal carcinoma. Application of monoclonal antibodies

In order to gain some insight into host cell accumulations within primary tumour, frozen sections from surgical specimens of laryngeal carcinoma were subjected to indirect immunofluorescence using a panel of monoclonal antibodies against various human lymphocyte subsets as well as macrophages. In addition, polyclonal antibodies against Ig were used in order to trace B cells. Numerous host cell infiltrates seen at the tumour periphery were composed of T4 (helper) lymphocytes and macrophages. Lymphocytes of OKT8 (suppressor/cytotoxic) and Leu-7 (NK cells) series were intermingled with tumour cells in the case of scanty infiltrates. Infiltrating cells were also linked to the presence of metastases in regional lymph nodes. OKT4-positive abundant infiltrates were usually accompanied by uninvolved nodes, while scanty ones with OKT8 specificity were relatively frequently seen in the patients with evidence of nodal metastases. These differences were not statistically significant, however, B cells as well as plasma cells were infrequently observed and were encountered both in tumour samples with intensive cellular infiltrates as well as in those with scanty ones.

Lectin-binding spectra in the hyperplastic human tonsil. Effect of formalin fixation and paraffin embedding on lectin affinity of tissue components

In order to determine the effect of routine fixation on the lectin affinity of tissue structures, we used unconjugated lectins and an indirect immunoalkaline-phosphatase method for frozen sections, and the peroxidase-anti-peroxidase method for paraffin-embedded, formalin-fixed tissue sections. Fourteen hyperplastic human tonsils were used, and the results of the binding spectra of each lectin were compared. In general, the binding spectrum detected in the paraffin sections was part of the broader range of affinity obtained in the frozen sections. The lectin receptors on the cell surface were especially affected by formalin fixation. On the other hand, the paraffin sections, because of their superior morphology, showed a better localization of the cytoplasmic reaction product and discriminated the cell types more accurately. Thus, the two tissue preparations are rather complementary. In the tonsil peanut agglutinin (PNA) and periodic acid/Concanavalin A (PA/Con A) proved to be suitable tools for distinguishing exactly between the crypt and the surface epithelium. Ulex europaeus agglutinin I (UEA) is a reliable endothelial marker with a strong affinity to the crypt epithelium. In the frozen sections, PNA regularly stained follicular-centre cells on their cell surface. PNA, Helix pomatia agglutinin (HPA), soybean agglutinin (SBA) and Con A stained the histiocytic population, especially PNA which additionally stained an "asteroid" histiocyte. This cell probably corresponds to the antigen-presenting histiocyte of the T-system.