Sture Falkmer

Immunohistochemical evidence of gastro-entero-pancreatic neurohormonal peptides of vertebrate type in the nervous system of the larva of a dipteran insect, the hoverfly, Eristalis aeneus

Using rabbit and guinea-pig antisera, raised against GEP neurohormonal peptides of mammalian origin, cells were observed in the brain and/or in the fused ventral ganglia of the last (fifth) larval instar of the hoverfly, Eristalis aeneus, being immunoreactive with antisera against insulin, somatostatin, glucagon, PP, secretin, gastrin/CCK/caerulein; substance P, enkephalin and endorphin. Most of these GEP neurohormonal peptides also occurred in nerve fibers. No immunoreactive cells or nerve fibers could be detected with antisera against GIP, VIP, (the central fragments of) CCK, bombesin or neurotensin. The antisera tested failed to reveal any immunoreactive cells or nerves in Weismanns ring (fused corpus allatum/corpus cardiacum and thoracic gland) or in different parts of the alimentary tract. The observations support the hypothesis that neuronal GEP hormonal peptide production in the brain is a genuinely original mechanism and the appearance of endocrine cells in the gut a later feature in evolution.

Immunohistochemical evidence of peptide hormones in endocrine tumors of the rectum

Twenty‐five endocrine tumors of the rectum (rectal carcinoids) were examined immunohistochemically for various pancreatic and gut neurohormonal polypeptides. Twenty‐one of the tumors were found to contain cells displaying pancreatic polypeptide (PP), glucagon, somatostatin, insulin, substance P, enkephalin or β‐endorphin immunoreactivity. At least 11 of the tumors contained more than one peptide hormone. In some of the tumors PP cells made up the major cell population, in others the glucagon cells constituted the majority. Only four of the tumors contained 5‐hydroxytryptamine. Rectal endocrine tumors seem unique among gut endocrine tumors in that they may store immunoreactive enkephalin, β‐endorphin and even insulin. None of the patients displayed the carcinoid syndrome; symptoms were usually vague and uncharacteristic. In many cases the tumor was found at routine examination.

Neurohormonal Peptides in Endocrine Tumors of the Pancreas, Stomach, and Upper Small Intestine: I. An Immunohistochemical Study of 27 Cases

Preliminary observations have indicated the existence of characteristic spectra of gastroenteropancreatic (GEP) neurohormonal peptides in endocrine tumors arising in foregut, midgut, and hindgut derivatives. In order to further explore this feature of GEP endocrine neoplasms, islet cell tumors from 14 patients were studied, as were endocrine tumors of the stomach, duodenum, and upper jejunum from 6, 5, and 2 patients, respectively. All tumors were examined immunohistochemically with antisera raised against islet hormones [insulin, somatostatin, glucagon, pancreatic polypeptide (PP)], peptides of the gastrin family [gastrin, cholecystokinin (CCK)], peptides of the secretin family [secretin, vasoactive intestinal peptide (VIP)], and substance P, neurotensin, leu-enkephalin, beta-endorphin, motilin, calcitonin, and ACTH. In addition, an ultrastructural investigation was made. Whenever possible, the immunohistochemical observations were correlated with the clinical manifestations and with the results of radioimmunochemical determination of GEP neurohormones in the blood. The pattern of immunoreactive neurohormonal peptides and the clinical picture were those to be expected in endocrine tumors arising in foregut derivatives. Some principles are proposed for the classification of GEP endocrine tumors on the basis of their histopathologic growth pattern, their spectrum of neurohormonal peptides, and their clinical manifestations.

Neurohormonal peptide immunoreactive cells in mucinous cystadenomas and cystadenocarcinomas of the ovary

In 144 benign mucinous cystadenomas of the ovary, 33 mucinous cystadenomas of borderline malignancy and 64 mucinous cystadenocarcinomas, the incidence of tumours containing argyrophil (and probably endocrine) cells was 18%, 33%, and 53%, respectively. The results of a semiquantitative assessment of the number of argyrophil cells in each individual tumour indicates that the greatest numbers occurred in the cystadenocarcinomas. As, however, the tumour cell density was larger in the cystadenocarcinomas than in the cystadenomas, and as the argyrophil cells often had a patchy distribution in the tumour epithelium, the incidence figures are unreliable. In addition, visualization of the argyrophil cells depends on an adequate fixation which is difficult to achieve in the routine processing of large tumour specimens. Many argyrophil cells in the cystadenocarcinomas displayed immunoreactivity with antisera raised against gastro-entero-pancreatic (GEP) neurohormonal peptides. In ten such tumours immunohistochemical evidence was obtained for the presence of the following neurohormonal peptides in the tumour cells: somatostatin, glucagon, gastrin/CCK, neurotensin, and enkephalin. Four of these ten cystadenocarcinomas were multihormonal, in that three contained two cell populations storing GEP neurohormonal peptides, and one tumour even three such populations. In the benign cystadenomas, however, no immunoreactive tumour cells were found. In those of borderline type, only two harboured immunoreactive cells. In both cases the tumour cells stored gastrin/CCK. The general appearance of the epithelium in the mucinous tumours — a continuous single-cell layer of mucin-producing cells intermingled with argyrophil cells of open type — and the spectrum of neurohormonal peptides observed, indicate an origin from the foregut endoderm.

Endocrine tumors of the ileum. Cytochemical and clinical aspects.

Sixteen patients with endocrine ileal tumors and liver metastases were analyzed with regard to the size, multicentricity, and growth pattern of the primary tumor, the occurrence of carcinoid syndrome, as well as the concentrations of serotonin and substance P (SP) in blood, 5-hydroxy-indole-acetic acid (5-HIAA) in urine, and the course of the disease. Excised specimens from the tumors were immediately processed for immunocytochemical investigations of the presence of neurohormonal peptides, using a broad spectrum of antisera and optimal histoprocessing techniques. In all patients the serotonin levels in blood and/or the 5-HIAA in urine were high. The SP concentration in plasma was markedly elevated in all but two of the ten patients investigated in this respect. A mixed growth pattern prevailed in the tumors of 7 patients with fatal disease. Serotonin cells were found in all tumors and SP-immunoreactive tumor cells in all but one; one of the carcinoids also contained a few tumor cells displaying enkephalin immunoreactivity. In conventionally fixed and paraffin embedded specimens of the same tumors usually no immunoreactive tumor cells at all could be demonstrated, showing that SP is among the peptides vulnerable to poor histotechniques. Nevertheless, SP, together with serotonin, constitute reliable clinical tumor markers for ileal carcinoids.

Surface infrastructure of the Small Intestine Mucosa in Healthy Children and Adults: A Scanning Electron Microscopic Study with Some Methodological Aspects

Biopsy specimens of light microscopically (LM) normal small intestine mucosa from eight healthy, constitutionally short-statured children without signs of gastrointestinal disease and six healthy adults were studied by scanning electron microscopy (SEM) supplemented by transmission electron microscopy (TEM). The effects on surface morphology of various preparative procedures were also investigated, using small intestine mucosa from cats and rats. Fixation with OsO4--either alone, or following glutaraldehyde fixation--markedly changed the surface ultrastructure compared to that after glutaraldehyde fixation only. By low power SEM, some differences were observed in the appearance of the small gut mucosa between adults and young children. In adults and in children above 3 years of age, the villi were usually shaped like fingers or leaves, but in infants, ridge-shaped villi predominated. The villi showed, however, a smooth surface in both infants and adults, and medium and high power SEM displayed similar pictures, irrespective of age; here the typical structural features of the normal small gut mucosa in humans were (1) distinct extrusion zones at the crests of the villi and almost no signs of enterocyte extrusion along the sides of the villi, and (2) regular enterocytes with polygonal, flat, apical surfaces covered by a thick glycocalyx that obscured the underlying microvilli.

Stereological studies on the rat small intestinal epithelium. III. Effects of short-term alloxan diabetes.

SummaryShort-term experimental diabetes was used to explore the effect of hyperplastic adaption of the small intestine mucosa on the structure of its absorptive cells. Diabetes was induced in adult female rats by intravenous alloxan administration under kidney protection; similar rats, injected with physiological saline, served as controls. Quantitative light microscopy, performed after 1 month of diabetes, revealed structural changes in the jejunal mucosa consistent with hyperplasia. These changes comprised increased height of the villi (31%) and increased depth of the crypts (34%) in comparison with the control rats. At the electron microscopical level, stereological measurements of the jejunal absorptive cells revealed a decrease in their apical surface area, both for the apical surface density (24%) and for the enlargement factor due to the microvilli (12%). In the duodenal mucosa, this kind of experimental diabetes did not induce any significant light microscopical or electron microscopical changes of the villi, the crypts, or the absorptive cells.It was concluded that the adaptive capacity of the structure of the small intestine mucosa to short-term experimental diabetes is more pronounced in the jejunum than in the duodenum, and that the adaptive response also includes alterations in the structure of the absorptive cells.

Nuclear DNA patterns and survival in metastasizing ileal carcinoids

AbstractThe prognostic value of assessing the tumor cell nuclear DNA pattern in metastasizing ileal carcinoids was evaluated in 22 patients. Eleven patients survived for 5 years or more after the diagnosis of the liver metastases, whereas 11 died within 3–4 years. Clinical data as well as histopathological and immunohistochemical tumor characteristics were studied. DNA measurements in single tumor cells were performed on histologic sections with a photographic cytophotometric method.nThe number of aneuploid tumor cells was almost negligible in all tumor specimens. When the number of nondiploid cells was evaluated, however, a tendency was observed for more frequent nondiploidy in tumor cells from patients surviving less than 3–4 years. Histopathologically and immunohistochemically, there were no clear-cut differences between the tumors of the 2 patient categories. Consequently, an assessment of the DNA pattern may help in determining the malignant potential of individual ileal carcinoids.RésuméLa valeur pronostique de lADN dans le noyau cellulaire tumoral en cas de tumeurs carcinoÏdes iléales métastasiantes a été étudiée chez 22 malades. Parmi ce groupe, 11 malades moururent 5 ans ou plus après le diagnostic de métastases hépatiques cependant que 11 moururent en 3–4 ans. Les données cliniques, les caractères histopathologiques et immunohistochimiques ont été étudiés. La mesure de lADN dans la cellule tumorale fut pratiquée sur les coupes histologiques par la méthode cyto-photométrique photographique.Le nombre de cellules tumorales aneuploÏdes fut négligeable au niveau de tous les spécimens étudiés. Quand le nombre des cellules non diploÏdes fut étudié, une tendance à une plus grande fréquence de ces éléments fut observée chez les malades dont la survie ne dépassa pas 3–4 ans. Histologiquement et lors de létude immunohistochimique, il ne fut pas constaté de différence nette entre les tumeurs des 2 catégories de malades. En conclusion, lévaluation de lADN peut permettre de déterminer le potentiel malin des carcinoÏdes iléaux.ResumenEl valor pronóstico de la determinación del patron nuclear de DNA de la célula tumoral en carcinoides ileales fue valorado en 22 pacientes. Once pacientes sobrevivieron por 5 años o más después del diagnóstico de metástasis hepáticas, en tanto que 11 murieron en 3–4 años. Se analizaron los datos clínicos, así como las características histopathológicas e inmunoquímicas del tumor. Las determinaciones de DNA en células tumorales individuales fueron realizadas sobre cortes histológicos por el método citofotométrico fotográfico.El nÚmero de celulas tumorales aneuploides fue casi insignificante en todos los especimenes tumorales. Sin embargo, cuando el nÚmero de células no diploides fue analizado, se observó una tendencia hacia la no diploidad en las tumorales de los pacientes que sobrevivieron menos de 3–4 anos. No se encontraron claras diferencias histopatológicas o inmunohistoquímicas entre los tumores de estas 2 categorías de pacientes. Por consiguiente, la valoración del patrón de DNA puede ser Útil en la determinación del potencial de malignidad de los carcinomas ileales.

Surface infrastructure of the Small Intestine Mucosa in Children with Celiac Disease. I. Untreated Disease and Effects of Long-Term Gluten Elimination and Challenge

Forty-eight gut mucosa specimens from 27 children with celiac disease, diagnosed by means of conventional serial biopsies taken at different dietary conditions, were studied by means of scanning electron microscopy (SEM). The observations were correlated with those made by concomitant dissection microscope (DM), light microscope (LM), and transmission electron microscope (TEM) examinations. Five children with constitutional short stature served as controls. The results of the SEM analyses were in good conformity with the observations made by DM, LM, and TEM. In addition, SEM was found to offer further structural variables to be analyzed. In active celiac disease and after challenge with dietary gluten, which is necessary to establish the diagnosis of children, the lesions specifically observed by SEM were (1) a strikingly uniform destruction of the villi and a distortion of the enterocytes but with preserved extrusion zones, and (2) a decrease and disruption of the glycocalyx of the enterocytes with marked irregularity of the microvilli. After successful dietary treatment and despite a normalization of the gut mucosa by routine LM, SEM often disclosed persisting lesions of the enterocytes. It was concluded that by inclusion of SEM in the routine assessments of gut biopsy specimens in children with celiac disease, the diagnostic precision becomes increased.