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A Sanderson

Publications and source records attributed to A Sanderson.

36 records · Page 2Linked to original sources

Surface phenotype of T cells producing growth of mucosal mast cells in normal rat bone marrow culture.

We have previously shown that lymphocytes from Nippostrongylus brasiliensis infected rats, when stimulated with antigen or concanavalin A (Con A) release factors which are comparable with murine IL-3. On addition of these factors to rat bone marrow cultures, mast cells with the morphological and biochemical properties of mucosal mast cells (MMC) proliferate and mature. Here, we use this system, along with monoclonal antibodies against rat T cells and the fluorescence-activated cell sorter (FACS), to isolate the subset of T cells responsible for the production of this MMC growth factor. Lymphocytes from N. brasiliensis infected rats were separated on the FACs into populations with and without the antigens defined by OX19, W3/25 and OX8 monoclonal antibodies; these antibodies label all T cells, T-helper cells and T-cytotoxic/suppressor cells, respectively. The resultant subsets were cultured in vitro with Con A. The supernatants were tested for the ability to induce MMC growth and differentiation in liquid cultures of normal rat bone marrow. The phenotype of the T cells producing this factor was established as being OX19+, W3/25+ and OX8-.

Animals↗

Axonal transport: a quantitative study of retained and transported protein fraction in the cat.

The fast axonal transport of proteins was studied in the cat sciatic nerve after injection of [3H]leucine into the spinal ganglion or the ventral horn of the seventh lumbar segment. The amount of transported proteins after ganglion injection was linearly related to the amount of label present at the ganglion. At variable intervals after ganglion or spinal cord injection, the sciatic nerves were sectioned in some experiments. The transport of proteins continued in the peripheral nerve stump in a wavelike manner, but the advancing wave leaves a labeled trail behind. A fraction of this trail corresponds to proteins moving at slower velocities than the velocity of proteins in the wave front. Another fraction of the trail corresponds to molecules retained by the axons. Each nerve segment of 5 mm in length retains 1.5% of the transported proteins, and the profile of retained proteins along the sciatic nerves follows a single exponential function. From the proportion of retained proteins, the concentration of transported proteins at the terminals of branching axons as a function of the branching ratio was estimated. In the case of motor axons innervating the soleus muscle of the cat, the concentration of recently transported proteins at the nerve terminals would be approximately 0.83% of the proteins leaving the spinal cord. This low concentration of transported proteins at the nerve terminals may explain the lability of neuromuscular synapses when axonal transport is decreased or interrupted.

Animals↗

Enzyme typing of Plasmodium falciparum from African and some other Old World countries.

Freeze-dried and freshly cultured isolates of Plasmodium falciparum from different countries have been examined for variation in six enzymes, GPI, PGD, LDH, GDH, ADA and PEPE, using starch gel electrophoresis. Variant forms of each enzyme occur. For most enzymes, similar forms occur in isolates from different parts of the world, although differences in frequencies of each form are found. LDH-2 has been found only in African isolates. PEPE variants vary markedly in their frequency between East and West Africa, although further work is needed to confirm this finding.

Adenosine Deaminase↗

Isolation of plasma-membrane components from cultured human pancreatic cancer cells by immuno-affinity chromatography of anti-beta 2M sepharose 6MB.

Human pancreatic exocrine adenocarcinoma cells established in tissue culture expressed both HLA and beta 2-microglobulin (beta 2M). Plasma-membrane components of this pancreatic cancer cell line were purified from plasma membrane fractions enriched by sucrose density-gradient centrifugation, using immunoaffinity chromatography on immobilized anti-human beta 2M antibody. Both rabbit and mouse monoclonal anti-beta 2M IgG were used, with a 20--25-fold overall purification of 5'-nucleotidase. The method was applicable to 5 x 10(7) cells and permitted the solubilization of membranes retained on the column, with the selective desorption of components not associated with beta 2M before the subsequent elution at pH 3 of beta 2M-associated macromolecules. The acid eluate contained one major and two minor bands in the 40--45,000 mol.-wt range with two additional enriched components of 18,000 and 22,000 dalton. A major carbohydrate-containing component of high mol. wt was also found to be associated with the pancreatic cancer-cell plasma membrane.

Adenocarcinoma↗

A genetic investigation of virulence in a rodent malaria parasite.

The genetic basis of virulence in a line (YM) of Plasmodium yoelii yoelii was investigated in a cross with a mild line (A/C). The blood forms of the virulent line developed extensively in mature erythrocytes of mice, causing death of the host within 7 days; infections with the mild line were normally restricted to reticulocytes, infected animals recovering after three weeks. Lines YM and A/C differed additionally in enzyme and drug-sensitivity markers. Studies on infections established from each line alone from sporozoite mixtures of the two lines and from the cross between the lines showed that the appearance of virulence had been caused by a genetic change in the parasite, and not by other factors such as a concurrent infection with another organism. An analysis of the characters of 56 clones derived from the cross showed that the virulence character had undergone recombination with the other markers, and appeared to be inherited in Mendelian fashion. Three clones exhibited atypical virulence, although it was not clear whether this had been produced by genetic recombination.

Animals↗

Severe combined immunodeficiency and adenosine deaminase deficiency.

Because others had described a lack of the enzyme adenosine deaminase as associated with severe combined immunodeficiency, we surveyed kindreds with infants affected with such an immunodeficiency. Three infants in two families with severe combined immunodeficiency were found to have no detectable erythrocyte adenosine deaminase. Eleven family members heterozygous for adenosine deaminase deficiency were encountered among the first-degree relatives; adenosine deaminase deficiency and severe combined immunodeficiency were associated and inherited as autosomal recessive traits in both kindreds. Successful bone-marrow transplantation was carried out in two of these infants. Normal immunologic function was established in both children, but the deficiency of adenosine deaminase persisted in their erythrocytes. The enzyme deficiency did not impair the successful establishment of normal humoral and cellular immunity by transplants of bone-marrow cells from siblings who were either normal or heterozygous for adenosine deaminase deficiency.

Adenosine↗

Genetic studies on Plasmodium chabaudi: recombination between enzyme markers.

Two lines of Plasmodium chabaudi differing in three characters have been crossed, using a technique previously described for P. yoelii. One line, termed 47AS, was characterized by an electrophoretic form of 6-hosphogluconate dehydrogenase, denoted 6PGD-2, a form of lactate dehydrogenase, denoted LDH-3, and was pyrimethanime-resistant. The second line, termed 10AJ, possessed enzyme forms of 6PGD-3 and LDH-2 and was pyrimethamine-sensitive. The cross was made by permitting mosquitoes to feed on a mixture of the two lines and infecting rodents with the resulting sporozoites. The products of the cross were cloned by dilution and examined for enzyme-type and drug-response. Results showed that recombination had occurred between each of the three characters. Clones characterized by 6PGD-2/LDH-2 and 6PGD-3/LDH-3 demonstrated recombination between the enzyme markers. The drug-resistance character segregated independently of either enzyme marker.

Animals↗

Glassy cell carcinoma of the uterine cervix. Report of a case with cytohistologic and immunohistochemical study.

BACKGROUND: Glassy cell carcinomas of the uterine cervix are poorly differentiated carcinomas composed of cells with a large, round to oval nucleus containing one or multiple prominent nucleoli, finely vacuolated eosinophilic to amphophilic cytoplasm and distinct cell borders. These cells occur in sheets and chords, with fibrovascular septae presenting a mixed inflammatory infiltrate. This neoplasm has a poor response to radiotherapy and a worse prognosis than the usual types of adenocarcinoma and squamous cell carcinoma. There are few reports on the cytologic and histopathologic features of this neoplasm. CASE: A 56-year-old woman presented with a large, exophytic cervical tumor. Exfoliative cytology showed clusters of cells and single cells with large, round to oval nuclei, with one or multiple nucleoli and moderate to large, finely granulated cytoplasm with distinct cell borders. The background of the smears had a polymorphous inflammatory infiltrate, necrotic debris and proteinaceous material. A high mitotic rate was observed, as were rare bizarre and atypical multinucleated cells. There was no evidence of koilocytes. These findings were highly suggestive of glassy cell carcinoma and were confirmed by the histologic and immunocytochemical findings, with positivity for cytokeratin (MNF116), vimentin and carcinoembryonic antigen and negativity for HMB-45. CONCLUSION: Glassy cell carcinoma of the cervix presents a cytologic picture that can be highly suggestive of the diagnosis in typical cases; however, in difficult cases ancillary techniques, such as immunocytochemistry, as well as histologic findings might confirm the diagnosis.

Carcinoma, Adenosquamous↗