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To understand better the relationships between blood-group antigens and bacterial constituents, examples of 23 gram-negative bacteria (representing the 10 genera Citrobacter, Edwardsiella, Enterobacter, Escherichia, Klebsiella, Proteus, Pseudomonas, Salmonella, Serratia, and Shigella) were tested for the presence of Kl-like antigens by hemagglutination-inhibition (HAI) assays against both IgG and IgM anti-Kl. Saline-suspended whole organisms, cell-free culture media, and disrupted organisms were used to test for such antigens in, on, and secreted by the microorganisms examined. Disrupted organisms of an isolate of Shigella sonnei nonspecifically inhibited IgG anti-Kl as well as IgG antibodies of the specificities Kpb, Fya, S, and c. However, only Escherichia coli 0125:B15, subtype 12808, had specific K1-like activity (no activity with other IgG [(k, Kpb, Jka, Fya, S, c] and IgM [A, B, M, P1] antibodies). Disrupted organisms inhibited IgM but not IgG anti-K1 in the HAI assay. A second subtype, E. coli 0125:B15, subtype 12809, exhibited no K1-like activity. These findings support the report of K1 activity in cell-free broth cultures of E. coli 0125:B15 (subtype unspecified). Thus, although not all E. coli 0125:B15 possesses K1-like activity, the finding of such activity in at least one E. coli subtype confirms the idea that bacterial components may play a role in the production of naturally occurring antibodies directed against non-ABO red cell antigens.

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In vivo patterns of lymphocytes sensitized against autologous tumor (in vitro) were studied in seven patients with metastatic cancer as a potential candidate for an alternative method of radioimmunodetection and adoptive immunocytotherapy. Peripheral blood lymphocytes (PBL) were either activated in Interleukin-2 (IL-2) [lymphokine activated killer (LAK) cells] or sensitized against autologous tumor cells by in vitro co-culture (IVC) and expanded in IL-2 (educated cells); both were then labelled with 111In. Labelled autologous cells (1 x 10(7)-5 x 10(8)) were administered to patients and biodistribution studied by imaging under a gamma camera at various time intervals. In 4/7 cases, imaging with the educated cells showed concentrations of radioactivity at sites that correlated positively with clinically detectable metastatic tumor. By contrast, only one instance of positive uptake was seen with the LAK cells. Other than slight fever in three cases, infusions of labelled PBL were well tolerated. Educated lymphocytes were cytotoxic against autologous tumor cells and the cytotoxic reactivities of the educated cells were maintained in continuous culture in IL-2 for 4-6 weeks. Evidence of accumulation of radiolabelled educated autologous cells at a significantly higher frequency than that of the LAK cells suggests that in vitro expanded educated PBL might be better candidates for radioimmunodetection of human cancer, and continuous cultures of such educated autologous PBL might be sources for repeated administration of these effector cells.

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To estimate the number of adults medically eligible to donate blood, the percent of the general population over the age of 16 deferrable by 13 current American Red Cross donor guidelines was calculated using the best available United States data. Categories examined included age, weight, hematocrit, pregnancy, blood pressure, heart disease, diabetes requiring insulin, male homosexual activity since 1977, intravenous drug use, sexual partner of high-risk group member, recent transfusion, history of cancer, and other (medical, surgical, travel history). Sex-specific total eligibility rates were estimated by serial multiplication of individual eligibility rates (1.0 minus deferral rates) to account for the proportionate overlap of independent categories, with corrections for expected associations between categories. The resultant eligibility rates for women (57%) and men (70%) indicate fewer eligible donors than commonly stated. Surrogate testing (ALT, anti-HBc) for non-A, non-B hepatitis would further reduce the percent of eligible donors to 55 and 67%, respectively. Based on the actual numbers of women and men in the population, these calculations indicate that an equal number of women and men are medically eligible to donate.

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Pentoxifylline, a hemorrheologic agent that lowers whole blood viscosity by increasing red cell membrane deformability, recently was approved by the Food and Drug Administration for the treatment of intermittent claudication. The effect of this drug on the phenotypic expression of red cell blood group antigens was studied with cells collected from six patients with intermittent claudication. After in vivo treatment with pentoxifylline, the serologic expression of the Wrb antigen increased. Comparative studies, using hemagglutination titration techniques, with red cells collected before treatment and 1 month after treatment, showed an increase in titer of at least two tubes and an increase in score of greater than 10 in all six patient samples drawn after treatment. No in vivo serologic changes were observed in any of the other antigens studied (A, B, D, C, E, c, e, M, N, S, s, U, P1, Leb, K, k, Fya, Fyb, Jka, Jkb, Yta). Protein analysis (sodium-dodecylsulfate polyacrylamide gel electrophoresis, silver stain) of red cell membranes prepared from blood collected before treatment and 1 month after treatment showed an increase in band density in the 24,000 and 14,000 dalton regions in the samples drawn after treatment. In vitro treatment of red cells with pentoxifylline and one of its major metabolites did not affect the phenotypic expression of any of the antigens studied, including Wrb.

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To evaluate the risk of significant plateletpheresis-induced thrombocytopenia in normal volunteer donors undergoing plateletpheresis less frequently than every 56 days and to help understand factors influencing platelet yield in these donors, pre- and postapheresis platelet counts (X 10(3)/microliter) and platelet yields were analyzed from 916 plateletpheresis procedures (Fenwal CS-3000) on 607 donors (405 men, 202 women). The mean preapheresis platelet count was 265 +/- 59 (SD) (range 155-650) (men 256 +/- 55 [170-444]; women 284 +/- 65 [155-650]; P less than .001, t-test). After an average platelet yield of 4.08 X 10(11), the mean postplatelet count was 185 +/- 46 (range 72-420) (men 184 +/- 42 [80-345]; women 194 +/- 52 [72-500]; P less than 0.1). The percent decrease in platelet count (mean 29.4 +/- 13, range -28.1-65.5) had positive correlations with platelet yield (P less than .01, r = 0.10), predonation platelet count (P less than .001, r = 0.29), and age (P less than .01, r = .10) and a negative correlation with weight (P less than .001, r = 0.18) Both the percent decrease and platelet yield were significantly higher in women than in men (P less than .001, t-test), and platelet yield was best predicted by preapheresis platelet count in both sexes (r = 0.65). The effects of plateletpheresis on donor platelet count thus vary widely among donors. Although a decrease of greater than 50% was not a rare event (5.9% of all procedures), in only three instances (0.3%) was the actual postapheresis platelet count below 100 (72, 94, 95). Thus, plateletpheresis in normal donors appears unlikely to produce clinically significant thrombocytopenia immediately after apheresis.

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To assess the functional viability of platelets collected by standard apheresis techniques using the Fenwal CS-3000 "closed system" and stored in Fenwal PL 732 plastic bags for 5 days at room temperature with agitation, a number of in vitro parameters (pH, morphology, platelet volume distribution, osmotic recovery, aggregation, and platelet-associated IgG) were examined as a function of storage time. During the first 24 hours of storage, minimal changes were observed in the test parameters with the exception of ADP-induced aggregation (75% decrease [10 uM], 84% decrease [5 microM]). Significant differences were observed between fresh (day 0) and 5-day-old platelet concentrates in all parameters except median platelet volume. These observed changes in in vitro test parameters with storage time are similar to those previously observed for comparably stored random single-donor platelet concentrates. Thus, the "closed-system" PL 732 apheresis platelet concentrates would be expected to be as effective in vivo as random single-donor platelet concentrates, while minimizing recipient exposure to transmissible agents of infectious disease.

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A paired prospective study was performed to compare the in vitro storage characteristics and in vivo kinetics of platelets stored in granulocyte-platelet concentrates prepared by apheresis with platelets prepared from whole blood. Platelet and granulocyte-platelet concentrates were collected from five healthy volunteer autologous donors and stored for 16 to 18 hours at 20 to 24 degrees C with and without agitation, respectively. After storage, pH, platelet count, percent release of beta-thromboglobulin, morphologic score, and percent osmotic recovery were measured. In addition, the granulocyte-platelet concentrates were assayed for total leukocyte count, release of lysozyme, and by several in vitro tests of granulocyte function. The platelets in both products were labeled with 111In oxine and infused into the donors. The pH of both products was above 6.0 at the end of storage. The units stored as platelet concentrates compared with those stored as granulocyte-platelet concentrates showed a higher percent release of beta-thromboglobulin, 18.4 +/- 4.0 percent versus 5.9 +/- 3.2 percent (mean +/- SD), but significantly better morphologic scores, 676 +/- 21 versus 525 +/- 56, and better osmotic recovery scores, 72 +/- 10 percent versus 40 +/- 7 percent, respectively (all p less than 0.05). The platelet concentrates (compared with the granulocyte-platelet product) had significantly better in vivo recovery, 49.5 +/- 15.8 percent versus 38.9 +/- 11.5 percent, and survival, 6.1 +/- 1.3 days versus 2.4 +/- 0.4 days, respectively (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

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An elderly, multiparous, multiply transfused woman developed post-transfusion purpura (PTP) after the transfusion of 2 units of leukocyte-poor red cells and was successfully treated by plasmapheresis and corticosteroids. Her pre-PTP transfusion history was characterized by frequent, multiple transfusions of platelet antigen-containing blood products 12 to 5.5 years prior to the onset of disease and, apart from the initiating transfusion, only frozen red cells in the 5.5 years immediately preceding the onset of thrombocytopenia. Leukocyte-poor red cells thus appear capable of initiating PTP. Use of a few units of frozen red cells may result in a shorter than normal refractory period, after which time PTP may occur upon exposure to sufficient platelet antigen.

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Management of hemophiliac patients with inhibitors can be a difficult problem. We report here a patient with severe hemophilia A, a high titer inhibitor, and an abdominal abscess requiring surgery. Despite significant cross reactivity of the inhibitor with porcine FVIII, he was successfully managed with plasmapheresis and porcine FVIII infusions. Other approaches to the management of such patients are briefly reviewed.

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Analogues of bromazepam [7-bromo-1,3-dihydro-5(2-pyridyl)-2H-1,4-benzodiazepin-2-one, A], which is a clinically useful minor tranquilizer, have been prepared by replacing the 2-pyridyl group at position 5 with 4-pyrimidyl (5), 2-pyrazinyl (8), 2,5-dimethylpyrazin-3-yl (10), and 2-pyrimidyl (12) groups. Low to moderate CNS activities in both mice and cat were found for all the new compounds. For the screening procedures used, the 2-pyrimidyl-substituted derivatives were found to be the most active new analogues although none of the activities exceeded those observed for bromazepam.

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