Subfractionation of human peripheral blood lymphocytes by partitioning in two-polymer aqueous phase systems. Characteristics of a small subpopulation of cells with high partition coefficient

Mixtures of aqueous solutions of dextran and poly(ethylene glycol) form immiscible 2-phase systems that are suitable for the separation of viable, functionally-competent cells on the basis of their surface properties. With the appropriate choice of ionic composition, these systems will separate cells on the basis of charge-related surface characteristics. We have previously shown that in charge-sensitive phase systems, human B lymphocytes have a low partition coefficient (K) and T cells have an intermediate K. The cell subpopulation with the highest K values contains large null lymphocytes that have most of the antibody-dependent and natural killer activities. The present study further characterizes this latter cell subpopulation. 8-33% of peripheral blood lymphocytes in normal persons had high K values. About 50% of these cells had typical Giemsa-staining granules characteristic of killer cells and one third had Fc receptors, but lacked complement receptors. Although 15-30% of the cells with high K values formed rosettes with sheep erythrocytes, there was virtually no response to T-cell mitogens such as PHA and Con A. Mixing cells having high K values with mitogen-responsive T cells from intermediate cell fractions revealed no evidence of suppressor-cell activity to explain the poor mitogen response. The studies indicate that a heterogeneous population of cells share charge-related surface properties resulting in a high partition coefficient. These cells comprise a significant proportion of human peripheral blood lymphocytes and include virtually all of the large granular lymphocytes as well as a large population without this morphology that shares the feature of unresponsiveness to T-cell mitogens.     

Use of a symblepharon ring for treatment of over-filtration and leaking blebs after glaucoma filtration surgery

We report the use of a symblepharon ring in the treatment of seven cases of flat anterior chamber (six cases of total iridocorneal touch, and one of corneallens touch) secondary to overfiltration or to bleb leak. In all cases, the anterior chamber reformed within 24 hours after the symblepharon ring was used. Advantages of using the ring are: (a) it permits testing of visual acuity, tonometry, and intraocular examination without removing it; (b) it does not require suturing to the conjunctiva; (c) it does not disturb the corneal epithelium; (d) it may be available at institutions lacking other shells; and (e) it is cost-effective.     

Antibodies to beta 2-microglobulin, the light-chain component of class I histocompatibility molecules, provide an activation signal to human lymphocytes

Antibodies to beta 2-microglobulin (beta 2m), the light-chain component of class I histocompatibility antigens, provide a strong co-stimulatory signal to human lymphocytes in the presence of phorbol ester. This activation signal requires a high concentration of antibody, whereas the effect on responses to a mitogenic lectin is exclusively inhibitory over a broad dose range. A rabbit polyclonal and a mouse monoclonal antibody to beta 2m were similarly co-stimulatory. Antibody to beta 2m was co-stimulatory with phorbol ester, but not calcium ionophore, suggesting that class I antigens play a role in the initiation of the 'first' signal of a recently described two-signal model of lymphocyte activation.     

Results of the tension-free vaginal tape procedure for stress incontinence: Patient''s perspective

BACKGROUND: To evaluate the results of the tension-free vaginal tape procedure (TVT) from a patient's perspective. METHODS: Between May 1999 and January 2002, 90 patients underwent a TVT for genuine stress incontinence (GSI) and mixed incontinence. Prior to the procedure, GSI was confirmed by clinical examination and urodynamic studies. Results were then audited from patient notes and the same patients were sent questionnaires to examine results from a patient perspective. RESULTS: Overall response rate to the questionnaire was 70 (77%). The mean age of the patients was 50.4 years (range 31-83 years). Sixty-one patients had spinal anesthesia, seven had general anesthesia and two had local anesthesia. Mean hospital stay was 3.36 days (range 2-14 days) and mean period from the operation to the time of the survey and audit was 16.34 months (range 3-28; SD 6.92). Thirty-nine (56%) of the 70 patients who answered said that the operation had cured their incontinence, 16 (23%) had an improvement in their symptoms, 7 (10%) had worsening of their symptoms and 8 (11%) felt that the operation did not make any difference. The overall success rate according to the patients' perspective was 79%, whereas our audit showed an overall success rate of 86% (77% and 82%, respectively, when we compared only the 66 patients who had both notes and replies available for analysis). CONCLUSION: Although a patient's perception regarding the success of TVT tends to differ from that of a clinician, it was not found to be statistically significant (P = 0.22, McNemar test). The TVT is a very successful operation, but realistic cure rates should be offered to patients.     

Hodgkin disease: CT of the thymus

The computed tomography (CT) scans in two groups of patients with Hodgkin disease were reviewed to determine the frequency of thymic enlargement. In 50 CT scans from 50 patients with evidence of thoracic disease on CT scans who were examined for primary staging, the thymus was enlarged in 15 of 50 (30%). Fifty CT scans were obtained from 44 patients at the time of 50 separate episodes of known or suspected relapse. Relapse occurred in the mediastinum in 12 episodes, lung parenchyma in five, and both sites in one. Thymic enlargement thought to be due to involvement by disease was present in seven of 18 (38%). Mediastinal disease was associated with thymic enlargement in all but one patient in whom a thymic cyst developed after radiation therapy. Differentiation of thymic enlargement from enlarged superior mediastinal lymph nodes was easily made in all but two patients. Thymic enlargement in the absence of lymph node enlargement may indicate a different disease, since isolated Hodgkin disease of the thymus is uncommon. Primary thymic tumor should be considered initially, whereas after treatment, rebound hyperplasia of the thymus may be the cause of enlargement.     

Solid and papillary epithelial neoplasms of the pancreas: CT findings

Five female patients and one male patient with solid and papillary epithelial neoplasms of the pancreas were examined with computed tomography (CT). The mean age of the patients was 27 years (range, 13-46 years). All cases showed well-encapsulated, round or lobulated masses consisting of both cystic and solid areas. Cystic portions showed CT numbers that suggested hemorrhagic necrosis. There were no internal septations within the masses. In three tumors located in the head of the pancreas, dilatation of the biliary tree was absent or minimal, although the masses were large. Two tumors contained calcifications. One tumor demonstrated metastatic deposits in liver and lymph nodes. Metastatic masses appeared similar to the primary pancreatic mass. Solid and papillary neoplasm of the pancreas should be the primary diagnostic consideration when characteristic CT findings are detected in a young female patient.     

Subfractionation of human T lymphocyte subpopulations by partitioning: surface heterogeneity of the OKT8/Leu2+ T cell subset.

Human peripheral blood mononuclear cells (PBMC) were subjected to countercurrent distribution in a charge-sensitive dextran-poly (ethylene glycol) aqueous two-phase system. Cells are thereby subfractionated on the basis of their charge-associated surface properties. The helper/inducer T cell subset (OKT4/Leu3+) has a single distribution curve with a low partition ratio (P). In contrast, the suppressor/cytotoxic (OKT8/Leu2+) subset is clearly heterogeneous and gives two peaks, one with a lower and the other with a higher P value. The cells in the latter peak constitute part of a minor subpopulation of cells enriched with natural killer (Leu7+) cells. Double labelling studies indicate that a majority of Leu2+ cells with a high P value also have a marker of natural killer cells (HNK-1), whereas the Leu2+ cells with low partition ratio are depleted with respect to cells bearing both markers.     

HLA-DR, DQ genotypes of celiac disease patients and healthy subjects from the West of Ireland

Celiac disease (CD) has one of the strongest class II HLA associations of any human illness. We used DNA-RFLP typing to study the class II HLA genotypes of celiac disease patients from the West of Ireland, the geographic area with the highest rate of celiac disease in the world. We confirmed the high frequency of HLA-DR3 in this population, and we were also able to demonstrate the additional risk of developing celiac disease imparted by HLA-DR7. This was done by clearly distinguishing DR7, DQ2 haplotypes from DR7, DQ9 haplotypes, and by "subtraction analysis" of haplotype frequencies. As reported in other populations, most of the patients without DR3 were heterozygous for DR7 and DR11 or 12 (DR5), or had DR4. We used PCR-RFLP and direct sequencing of amplified DNA to examine HLA-DR4 subtypes. The frequency of HLA-DR4 was markedly decreased in patients compared with controls (p=0.000001) and there was a significant alteration of DR4 subtypes of the patients compared with controls (p=0.0227). Moreover, all of the CD patients (5 of 5) with DR4 had a haplotype associated with the DQB1*0302 allele compared with only 11 of 23 control subjects with DR4. Our results in this population with exceptionally high risk of CD strongly support the DQ heterodimer hypothesis and suggest that the recently described sequence difference between the DQB1*02 alleles of DR3 and DR7 may contribute to a synergistic increased risk when these haplotypes are inherited together. In addition, our findings suggest a role for HLA-DQ in DR4-associated CD.