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Background: The AABB-ISCT Joint Working Group Stability Project Team (SPT) was assigned to roadmap a path toward standardization of cryopreserved hematopoietic stem/progenitor cell (HSPC) stability programs. HSPC stability encompasses a broad scope of conditions including non-frozen ("fresh") and cryopreserved cell products, and varying methods for storage, thaw, and administration. This report assessed current practices and focused solely on cryopreserved HSPC cell therapy products to establish preliminary recommendations for a stability program roadmap., Methods: A survey was prepared by the SPT and distributed to ISCT and AABB members. Survey results were summarized and recommendations were outlined based on the responses from the survey. This report highlights current practices for cryopreserved HSPC stability programs, including additional considerations and recommendations., Results and Discussion: Eighty-two (82) centers worldwide participated in the survey. Survey results indicate variability across programs. HSPC stability depends on multiple factors within the processing facility (e.g., cryopreservation techniques, reagents used, and storage temperature) and independent variables (e.g., donor-related factors and starting material variability). While retention of hematopoietic engraftment potential is the primary goal for cryopreserved HSPC stability, engraftment results should not be used as the sole metric for stability programs. Based on the survey results, the SPT provides recommendations for consideration., Conclusions: The SPT recommendations for best practices are not intended to replace existing standards. The survey results emphasize the need for the community to optimize best practices and consider initiating collaborative projects to improve the standardization of cryopreserved HSPC stability programs for cell therapy products., Competing Interests: Conflicts of interest This is a joint cooperation between the two organizations, ISCT and AABB, who have agreed to share the output of this work and to co-publish in both Transfusion (https://www.aabb.org/news-resources/news/transfusion-journal) and Cytotherapy (https://www.isct-cytotherapy.org/). This manuscript has not been published or is not under consideration by another journal. The authors of this manuscript have read and understood this journal's polices, and believe that the studies presented here do not violate any of these. The authors have disclosed no conflicts of interest., (Copyright © 2022. Published by Elsevier Inc.)

Background and Objectives: Cytokine release syndrome in COVID-19 is due to a pathological inflammatory response of raised cytokines. Removal of these cytokines by therapeutic plasma exchange (TPE) prior to end-organ damage may improve clinical outcomes. This manuscript is intended to serve as a preliminary guidance document for application of TPE in patients with severe COVID-19., Material and Methods: The available literature pertaining to the role of TPE for treatment of COVID-19 patients was reviewed to guide optimal management. It included indication, contraindication, optimal timing of initiation and termination of TPE, vascular access and anticoagulants, numbers and mode of procedures, outcome measures and adverse events., Results: Out of a total of 78 articles, only 65 were directly related to the topic. From these 65, only 32 were acceptable as primary source, while 33 were used as supporting references. TPE in critically ill COVID-19 patients may be classified under ASFA category III grade 2B. The early initiation of TPE for 1-1·5 patient's plasma volume with fresh frozen plasma, or 4-5% albumin or COVID-19 convalescent plasma as replacement fluids before multiorgan failure, has better chances of recovery. The number of procedures can vary from three to nine depending on patient response., Conclusion: TPE in COVID-19 patients may help by removing toxic cytokines, viral particles and/or by correcting coagulopathy or restoring endothelial membrane. Severity score (SOFA & APACHE II) and cytokine levels (IL-6, C-reactive protein) can be used to execute TPE therapy and to monitor response in COVID-19 patients., (© 2021 International Society of Blood Transfusion.)

Background and Objectives: The International Haemovigilance Network collects aggregate data on complications of blood donation from member haemovigilance systems (HVS). We analysed the data collected in 2006-2016 in order to learn from it and consider future improvements., Materials and Methods: National HVS entered annual data on donation complications and on annual whole blood and apheresis donations in the 'ISTARE' (International Surveillance of Transfusion Adverse Reactions and Events) online database. We calculated national and aggregate donation complication rates., Results: Twenty-four HVS provided data for 138 country years (CY; median 7 CY, IQR 2-8), covering 155 M donations. The overall complication rate was 6·3/1000 donations and the median country rate 3·2/1000 (IQR 1·1-10·1). Overall and severe complication rates varied considerably between HVS. Vasovagal reactions (VVR) were most commonly reported: 4·6/1000 donations, median country rate 3·1/1000 donations (IQR 0·6-7·7). Rare complications included generalized allergic reaction (0·10/100 000) and major blood vessel injury (category available since 2015; 0·12/100 000). Eighteen HVS reported complications of whole blood donation (WBD) and apheresis separately (89 CY, 101·6 M WBD and 26·3 M apheresis donations). The median country VVR rate was 3·4/1000 WBD (IQR 1·0-9·1) and 1·5/1000 apheresis donations (1·0-4·2). Rates of venepuncture-related complications tended to be higher for apheresis: the median country rate of reported haematomas was 0·39/1000 WBD (IQR 0·31-1·2) vs. 4·2/1000 apheresis donations (0·69-5·6)., Conclusion: International reporting allows HVS to study rates of blood donation complications and capture information about very rare events. The present variability of reporting and severity assessment hampers comparisons between HVS and requires further work., (© 2020 International Society of Blood Transfusion.)

Lack of access to quality diagnostics remains a major contributor to health burden in resource-limited settings. It has been more than 10 years since ASSURED (affordable, sensitive, specific, user-friendly, rapid, equipment-free, delivered) was coined to describe the ideal test to meet the needs of the developing world. Since its initial publication, technological innovations have led to the development of diagnostics that address the ASSURED criteria, but challenges remain. From this perspective, we assess factors contributing to the success and failure of ASSURED diagnostics, lessons learnt in the implementation of ASSURED tests over the past decade, and highlight additional conditions that should be considered in addressing point-of-care needs. With rapid advances in digital technology and mobile health (m-health), future diagnostics should incorporate these elements to give us REASSURED diagnostic systems that can inform disease control strategies in real-time, strengthen the efficiency of health care systems and improve patient outcomes.

Background: In December 2014, a multinational collaboration of hemovigilance experts from the International Society of Blood Transfusion (ISBT), the International Hemovigilance Network, and AABB published harmonized definitions of complications related to blood donation titled "Standard for Surveillance of Complications Related to Blood Donation." Both mandatory and optional terms were included. The definitions are endorsed by the Alliance of Blood Operators and the European Blood Alliance., Study Design and Methods: The objective of this study was to validate harmonized donor hemovigilance definitions with potential users. In June 2016, 30 real-world cases were sent to potential users around the world along with the definitions, an answer sheet, and instructions on how to complete the validation exercise., Results: Overall, 54 responses from 25 countries were received, including over 400 comments. The results were presented for feedback at both ISBT and AABB meetings. Case diagnoses were consistent across most responders. Exceptions were rare adverse events, nonstandard presentations, or incomplete information. In general, the application of optional definitions, including severity grading and imputability, had the most variability., Conclusion: The use of standardized terms in the donor setting serves to increase focus on donor safety, facilitate conversation, foster exchange of information, and frame questions for future research. Overall, the definitions provide adequate coverage of donor reactions; however, some terms require clarification. Severity grading and imputability and other optional terms need clear and objective definitions and instructions on when and how to use them. Additional feedback and final recommendations are summarized in this report., (© 2018 AABB.)

We present a simple microfluidic system for rapid screening of Escherichia coli (E. coli) O157:H7 employing the specificity of immunomagnetic separation (IMS) via immiscible filtration assisted by surface tension (IFAST), and the sensitivity of the subsequent adenosine triphosphate (ATP) assay by the bioluminescence luciferin/luciferase reaction. The developed device was capable of detecting E. coli O157:H7 from just 6 colony forming units (CFU) in 1 mL spiked buffer within 20 min. When tested with wastewater discharged effluent samples, without pre-concentration, the device demonstrated the ability to detect 10 4  CFU per mL seeded; suggesting great potential for point-of-need microbiological water quality monitoring., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The presented work demonstrates novel functionalities of hybrid paper-polymer centrifugal devices for assay performance enhancement that leverage the advantages of both paper-based and centrifugal microfluidic platforms. The fluid flow is manipulated by balancing the capillary force of paper inserts with the centrifugal force generated by disc rotation to enhance the signal of a colorimetric lateral flow immunoassay for pathogenic E. coli . Low-cost centrifugation for pre-concentration of bacteria was demonstrated by sample sedimentation at high rotational speeds before supernatant removal by a paper insert via capillary force after deceleration. The live bacteria capture efficiency of the device was similar to a commercial centrifuge. This pre-concentrated sample when combined with gold nanoparticle immunoconjugate probes resulted in a detection limit that is 10× lower than a non-concentrated sample for a lateral flow immunoassay. Signal enhancement was also demonstrated through rotational speed variation to prevent the flow for on-device incubation and to reduce the flow rate, thus increasing the sample residence time for the improved capture of gold nanoparticle-bacteria complexes in an integrated paper microfluidic assay. Finally, multiple sequential steps including sample pre-concentration, filtration, incubation, target capture by an integrated paper microfluidic assay, silver enhancement and quenching, and index matching were completed within a single device. The detection limit was 10 5 colony forming units per ml, a 100× improvement over a similar paper-based lateral flow assay. The techniques utilize the advantages of paper-based microfluidic devices, while facilitating additional functionalities with a centrifugal microfluidic platform for detection performance enhancement in a low-cost, automated platform amenable to point-of-care environments.

We present a novel use for channel structures in microfluidic devices, whereby two two-phase emulsions, one created on-chip, the other off-chip, are rapidly mixed with each other in order to allow for the coalescence of one emulsion with the other. This approach has been motivated by the difficulty in introducing aqueous cross linking agents into droplets by utilising conventional approaches. These conventional approaches include continuous introduction of the different aqueous reagents before droplet formation or alternatively formation of individual droplets of each reagent and subsequent droplet merging later in the microfluidic device. We show that our approach can decrease the mixing time for these fluidic systems by a factor greater than 10 times when compared to a standard microfluidic channel without structures, thereby also allowing for additional reaction time within the microfluidic device. This method shows an application for microfluidic channel structures not before demonstrated, also demonstrating an alternative method for introducing reagents such as cross linkers which link polymer chains to form particles, and provides an example where enzymes are immobilized in monodisperse particles.

Background: Transfusion-related acute lung injury (TRALI) is the most common cause of transfusion-related mortality and has been linked to the infusion of donor antibodies directed against recipient HLA class I antigens. We hypothesize that antibodies against HLA class I antigens bind to the antigens on the neutrophil (PMN) surface and induce priming and PMN cytotoxicity as the second event in a two-event in vitro model of PMN-mediated cytotoxicity., Methods: Isolated PMNs from HLA-A2 homozygotes, heterozygotes and null donors were incubated with a monoclonal antibody to HLA-A2 and a human polyclonal IgG to HLA-A2 and priming of the oxidase was measured. The monoclonal antibodies and PMNs from these three groups were then used in a two-event model of PMN cytotoxicity., Results: The antibodies to HLA-A2 both primed PMNs from HLA-A2 homozygotes but not from heterozygotes or nulls. Antibodies to HLA-A2 also served as the second event in a two-event model to induce PMN cytotoxicity of HLA-A2 homozygous PMNs., Conclusion: Antibodies to HLA class I antigens may directly prime/activate PMNs through the ligation of the antigen on the cell surface, and the antigen density appears to be important for these changes in PMN physiology., (© 2013 International Society of Blood Transfusion.)

Transfusion-related acute lung injury (TRALI) remains a significant cause of transfusion-related mortality with red cell transfusion. We hypothesize that prestorage filtration may reduce proinflammatory activity in the red blood cell (RBC) supernatant and prevent TRALI. Filters were manufactured for both small volumes and RBC units. Plasma containing antibodies to human lymphocyte antigen (HLA)-A2 or human neutrophil antigen (HNA)-3a was filtered, and immunoglobulins and specific HNA-3a and HLA-2a neutrophil (PMN) priming activity were measured. Antibodies to OX27 were added to plasma, and filtration was evaluated in a 2-event animal model of TRALI. RBC units from 31 donors known to have antibodies against HLA antigens and from 16 antibody-negative controls were filtered. Furthermore, 4 RBC units were drawn and underwent standard leukoreduction. Immunoglobulins, HLA antibodies, PMN priming activity, and the ability to induce TRALI in an animal model were measured. Small-volume filtration of plasma removed >96% of IgG, antibodies to HLA-A2 and HNA-3a, and their respective priming activity, as well as mitigating antibody-mediated in vivo TRALI. In RBC units, experimental filtration removed antibodies to HLA antigens and inhibited the accumulation of lipid priming activity and lipid-mediated TRALI. We conclude that filtration removes proinflammatory activity and the ability to induce TRALI from RBCs and may represent a TRALI mitigation step., (© 2014 by The American Society of Hematology.)

Background: Red blood cell (RBC) transfusion is a life-saving intervention for critically ill patients; however, it has been linked to increased morbidity and mortality. We hypothesize that a number of important proteins accumulate during routine storage of RBCs, which may explain some of the adverse effects seen in transfused patients., Study Design: Five RBC units were drawn and divided (half prestorage leucoreduced (LR-RBC) and half left as an unmodified control (RBC). The supernatant was separated on days 1 and 42 of storage and proteomic analyses completed with in-gel tryptic digestion and nano-liquid chromatography tandem mass spectrometry., Results: In RBC supernatants, 401 proteins were identified: 203 increased with storage, 114 decreased, and 84 were unchanged. In LR-RBC supernatant, 231 proteins were identified: 84 increased with storage, 30 decreased, and 117 were unchanged. Prestorage leucoreduction removed many platelet- and leucocyte-derived structural proteins; however, a number of intracellular proteins accumulated including peroxiredoxins (Prdx) 6 and latexin. The increases were confirmed by immunoblotting, including the T-phosphorylation of Prdx-6, indicating that it may be functioning as an active phospholipase. Active matrix metalloproteinase-9 also increased with a coinciding decrease in the metalloproteinase inhibitor 1 and cystatin C., Conclusion: We conclude that a number of proteins increase with RBC storage, which is partially ameliorated with leucoreduction, and transfusion of stored RBCs may introduce mediators that result in adverse events in the transfused host., (© 2013 International Society of Blood Transfusion.)

The growing use of group AB plasma in the United States in recent years poses unique challenges to blood centers and transfusion services. Blood centers must collect sufficient plasma components from a limited pool of group AB donors while taking steps to improve transfusion safety that further restricts the available supply. Transfusion services, on the other hand, must use the finite resource in the most conscientious and medically appropriate manner. Recently, many investigations have challenged long-held beliefs about transfusion practice and appropriate indications for blood components across a variety of specialties. Balancing supply and demand of group AB plasma requires collaboration between blood suppliers and transfusion services, and opportunities for improvement exist on both sides of the equation., (© 2013 American Association of Blood Banks.)

West Nile virus (WNV), an arbovirus maintained in a bird-mosquito enzootic cycle, can infect other vertebrates including humans. WNV was first reported in the US in 1999 where, to date, three genotypes belonging to WNV lineage I have been described (NY99, WN02, SW/WN03). We report here the WNV sequences obtained from two birds, one mosquito, and 29 selected human samples acquired during the US epidemics from 2006-2011 and our examination of the evolutionary dynamics in the open-reading frame of WNV isolates reported from 1999-2011. Maximum-likelihood and Bayesian methods were used to perform the phylogenetic analyses and selection pressure analyses were conducted with the HyPhy package. Phylogenetic analysis identified human WNV isolates within the main WNV genotypes that have circulated in the US. Within genotype SW/WN03, we have identified a cluster with strains derived from blood donors and birds from Idaho and North Dakota collected during 2006-2007, termed here MW/WN06. Using different codon-based and branch-site selection models, we detected a number of codons subjected to positive pressure in WNV genes. The mean nucleotide substitution rate for WNV isolates obtained from humans was calculated to be 5.06×10(-4) substitutions/site/year (s/s/y). The Bayesian skyline plot shows that after a period of high genetic variability following the introduction of WNV into the US, the WNV population appears to have reached genetic stability. The establishment of WNV in the US represents a unique opportunity to understand how an arbovirus adapts and evolves in a naïve environment. We describe a novel, well-supported cluster of WNV formed by strains collected from humans and birds from Idaho and North Dakota. Adequate genetic surveillance is essential to public health since new mutants could potentially affect viral pathogenesis, decrease performance of diagnostic assays, and negatively impact the efficacy of vaccines and the development of specific therapies.

Background and Objectives: Plasma and platelet concentrates are disproportionately implicated in transfusion-related acute lung injury (TRALI). Platelet-derived pro-inflammatory mediators, including soluble CD40 ligand (sCD40L), accumulate during storage. We hypothesized that platelet contamination induces sCD40L generation that causes neutrophil [polymorphonuclear leucocyte (PMN)] priming and PMN-mediated cytotoxicity., Materials and Methods: Plasma was untreated, centrifuged (12,500 g) or separated from leucoreduced whole blood (WBLR) prior to freezing. Platelet counts and sCD40L concentrations were measured 1-5 days post-thaw. The plasma was assayed for PMN priming activity and was used in a two-event in vitro model of PMN-mediated human pulmonary microvascular endothelial cell (HMVEC) cytotoxicity., Results: Untreated plasma contained 42±4·2×10(3)/μl platelets, which generated sCD40L accumulation (1·6-eight-fold vs. controls). Priming activity and HMVEC cytotoxicity were directly proportional to sCD40L concentration. WBLR and centrifugation reduced platelet and sCD40L contamination, abrogating the pro-inflammatory potential., Conclusion: Platelet contamination causes sCD40L accumulation in stored plasma that may contribute to TRALI. Platelet reduction is potentially the first TRALI mitigation effort in plasma manufacturing., (© 2011 The Author(s). Vox Sanguinis © 2011 International Society of Blood Transfusion.)

Background: Plasma is vital for the resuscitation of injured patients and to restore necessary procoagulants, especially Factors (F)II, FV, FVII, FX, and FXIII; however, female plasma has been implicated in the majority of transfusion-related acute lung injury (TRALI) cases and male-only plasma transfusion regimens have significantly decreased the incidence of TRALI. Little is known about the human plasma proteome, and no comparisons have been made between male and female plasma; therefore, we hypothesize that there are significant differences between plasma from male and female donors., Study Design and Methods: Five units of fresh-frozen plasma each were collected from nulliparous female donors and male donors, and the proteome was analyzed by depleting the 14 most common proteins by immunoaffinity columns followed by protein separation by one dimension gel electrophoresis, tryptic digestion of the proteins, analysis of the peptides by liquid chromatography-tandem mass spectrometry, and identification employing human protein sequence databases., Results: Female plasma versus male plasma contained pregnancy zone protein (419- to 580-fold), FV (twofold), α(1)-antitrypsin (twofold), β(2) -microglobulin (twofold), and Complement Factors H and C4B (1.5- to 2-fold) at significantly higher concentrations than males and males contained significant increases in Fc-binding protein (twofold), protein Z-dependent protease inhibitor (twofold), phosphatidylinositol glycan-specific phospholipase (fourfold), protein S-100 (threefold), and transgelin-2 (14-fold) versus females (p < 0.005). The increases in FV, α(1)-antitrypsin, and β(2)-microglobulin were confirmed by an activity assay or immunoblots., Conclusion: We conclude that there are proteomic differences between male and female plasma, which could be exploited to improve clinical outcomes in transfused patients., (© 2012 American Association of Blood Banks.)

A method to easily manufacture and assemble a polydimethylsiloxane (PDMS) based microfluidic device is described. The method uses low cost materials and re-usable laser cut polymethyl methacrylate (PMMA) parts. In addition, the thickness of PDMS layers can be controlled and both PDMS layer surfaces are flat, which allows for multi-layer PDMS structures to be assembled. The use of mechanical clamping to seal the structure allows for easy cleaning and re-use of the manufactured part as it can be taken apart at any time. In this way, selected layers can be re-used or replaced. The process described can be easily adopted and utilised without the need for any costly clean room facilities or equipment such as oxygen bonders, making it ideal for laboratories, universities, and classrooms exploring microfluidics applications.

The following abstracts are compiled from Check Sample exercises published in 2008. These peer-reviewed case studies assist laboratory professionals with continuing medical education and are developed in the areas of clinical chemistry, cytopathology, forensic pathology, hematology, microbiology, surgical pathology, and transfusion medicine. Abstracts for all exercises published in the program will appear annually in AJCP.

Background: Bacterial contamination of platelet (PLT) components is a leading cause of transfusion-related fatality. AABB and The College of American Pathologists require that blood centers and transfusion services have a process for detecting bacterial contamination in PLT products., Case Report: Leclercia adecarboxylata was isolated from the donated blood of a healthy, asymptomatic 61-year-old man. The PLT donation was collected by apheresis method and was separated into three daughter or split products. Samples from all three products tested positive for the presence of bacterial contamination. L. adecarboxylata was subsequently identified in two of three products. The blood donor's records were reviewed and the donor was interviewed by telephone. The only possible risk identified during the interview was a questionable contact dermatitis, away from the antecubital fossa, thought to be due to poison ivy exposure before the donation. All subsequent donations have tested negative for the presence of bacterial contamination. The organism is a Gram-negative bacillus variant of the Enterobacteriaceae family and known nosocomial isolate. It has been previously reported as a rarely isolated opportunistic pathogen mostly associated with patients having compromised immunity, chronic or inflammatory illness, catheter-related bacteremia, or mixed-bacterial wounds. L. adecarboxylata was originally identified in water, foods, and environment., Conclusion: This is the first known report of isolation of L. adecarboxylata from the blood donation of an apparently healthy individual and could represent transient asymptomatic bacteremia or more likely contamination by epidermal flora. The organism may be underrecognized due to its close resemblance to Escherichia coli.

BALB/c mice are susceptible to the induction of Graves' hyperthyroidism. To investigate the susceptibility of BALB/c substrains of mice to the induction of hyperthyroidism, we immunized BALB/cJ and BALB/cByJ mice with an adenovirus expressing amino acid residues 1-289 of thyrotropin receptor (TSHR). The data presented in this article showed that 17 of 26 (65%) BALB/c and only 4 of 30 (13%) BALB/cBy mice developed hyperthyroidism. Hyperthyroid mice displayed characteristics of Graves' disease, such as thyroid-stimulating antibodies and enlarged thyroid glands. To explore the differences in the susceptibility of these substrains for hyperthyroidism, we examined the TSHR antibodies in three different assays. The TSHR antibodies determined in a radioreceptor assay (TSH binding inhibitory immunoglobulins) were similar in both of these BALB/c substrains. The TSHR antibody titers of total IgG, IgG1, and IgG2a were measured by an enzyme-linked immunosorbent assay and were found to be similar in these mice. There were no significant differences between these two groups of mice in the thyroid-stimulating antibody activity. However, BALB/cBy mice had significantly higher TSH-blocking antibody activity compared to BALB/c mice. TSHR-specific proliferation of splenocytes and secretion of cytokines interferon-gamma and interleukin-4 by spleen cells were comparable in both the groups. BALB/cJ and BALB/cByJ mice both belong to same MHC haplotype, H-2(d), but differ in the Qa-2 region of class Ib molecule. This report shows the importance of other genes, such as Qa-2 region of class Ib molecule in addition to MHC class II, in the susceptibility of Graves' hyperthyroidism.

T helper type 1 (Th1) and Th2 cells have critical roles in the development of cell-mediated and humoral immune responses, respectively. This division of function predicts that Th1 cells mediate inflammatory diseases and Th2 cells promote antibody (Ab)-mediated autoimmunity. Our previous studies using HEK-293 cells expressing the extracellular domain of the TSH receptor (TSHR) showed that Stat4-/- mice, which lack Th1 cells, are susceptible, whereas Stat6-/- mice, which lack Th2 cells, are resistant to the induction of Graves' hyperthyroidism. To investigate the role of Stat4 and Stat6 genes in other murine models of hyperthyroidism, we injected wild-type BALB/c, Stat4-/-, and Stat6-/- mice with an adenovirus expressing amino acid residues 1-289 of TSHR (TSHR-289-ad or 289-ad). The viral system induces a much stronger immune response with much more rapid onset of disease. Our results showed that 56% of wild-type, 75% of Stat4-/-, and 39% of Stat6-/- mice developed hyperthyroidism. Hyperthyroid mice exhibited thyroid stimulatory Abs. The Stat4-/- mice developed a higher incidence and greater severity of hyperthyroidism compared with wild-type and Stat6-/- mice. BALB/c and Stat4-/- mice showed significantly higher TSHR Abs of the IgG1 subclass and IL-4 compared with Stat6-/- mice. In contrast, Stat6-/- mice had predominantly the IgG2a subclass of TSHR Ab and produced significantly higher amounts of IFN-gamma than BALB/c and Stat4-/- mice. All hyperthyroid mice showed enlarged thyroid glands with hyperactivity. These results suggest that in the TSHR-289-ad model, the Th2 cells are more efficient in mediating disease, but in the absence of Th2 cells, Th1 cells may still initiate a reduced incidence of Graves' hyperthyroidism.

The role of T helper (Th) cells in experimental models of Graves' hyperthyroidism is still somewhat controversial. To further investigate the role of Th1- and Th2-dependent immunity during the development of Graves' hyperthyroidism, we tested mice with targeted deletion of signal transducer and activator of transcription-4 (Stat4) or Stat6 genes that, respectively, have impaired Th1 and Th2 immunity. We immunized wild-type BALB/c, Stat4(-/-), or Stat6(-/-) mice with human embryonic kidney cells (293 cells) expressing the extracellular domain of human TSH receptor (293-TBP cells). Fifty percent of wild-type BALB/c and Stat4(-/-) mice developed Graves' hyperthyroidism with elevated serum T(4) levels and thyroid stimulatory antibodies. In contrast, Stat6(-/-) mice resisted development of the disease. Stat4(-/-) mice exhibited a dominant Th2 immune response characterized by the production of IL-4 and IgG1 anti-TSH receptor antibodies. However, Stat6(-/-) mice displayed a strong Th1 immune response characterized by the production of interferon-gamma and IgG2a antibodies. Hyperthyroid mice showed enlargement of thyroid glands with hypertrophy and decreased amounts of colloid material, all characteristics of Graves' disease. These data demonstrate that in this model, Stat6-dependent Th2 immunity is critical for the development of Graves' hyperthyroidism.

Gliomas were induced in adult male Sprague-Dawley rats by continuous exposure to 100 ppm of N-nitrosmethylurea (MNU) in drinking water. Latency periods for such tumors were 20 and 50 weeks following completion of exposure intervals of 20, 15, and 10 weeks, respectively. Based on histomorphology and the pattern of GFAP immunoreactivity, a large percentage of MNU-induced tumors (>40%) were anaplastic mixed gliomas, having both neoplastic astrocytic and oligodendroglial components. Typical oligodendrogliomas and astrocytomas also occurred less frequently. Unlike the majority of tumors induced by ethylnitrosourea (ENU), MNU yielded glial tumors that did not express synaptophysin. Anaplastic mixed gliomas and glioblastoma multiforme (GBMs) had no missense p53 mutations in the commonly mutated exons 4 through 8 and did not overexpress wild-type p53, suggesting that MNU-induced oncogenesis in rat brain tumors may not require inactivation/alteration of the p53 tumor suppressor gene. The K-ras gene was also analyzed and found to have no activating mutations in brain tumors. This model is suitable for studying genetic events leading to the majority of gliomas that apparently express functional p53.

Background: The purpose of this study was to assess the occurrence of various morphologic types of leukemia and myeloma within patient demographic groups and to correlate findings with data-reporting periods and other variables, such as 5-year relative survival., Methods: Data from 31,850 cases of multiple subgroups of acute and chronic leukemia, 12,237 cases of myeloma, and 321 cases of "other" lymphoreticular neoplasms were collected by the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) program. The data were examined by age, sex, race, age-specific and age-adjusted incidence rate, and patient 5-year relative survival during three reporting periods: 1973-1977, 1978-1982, and 1983-1987., Results: The age-adjusted incidence rate for all categories of leukemia combined has been constant, but there has been an increase in the relative frequency (percentage) of acute lymphoid leukemia (ALL) in the general population and a rising incidence rate of myeloid leukemia in the black population. The increase of ALL is offset by a decline of acute myeloid leukemias (AMLs) and acute leukemia, not otherwise specified. The age-adjusted rate of ALL in whites, 1.5 per 100,000 per year, is twice that of blacks, 0.8. The rates for each of the major categories of leukemia are considerably higher in males than in females. Five-year survival rates changed very little for leukemias over the 15 years of the study except for ALL, in which there was a marked improvement between the first (1973-1977) (39.1%) and second (1978-1982) (51.3%) reporting period. The SEER data confirm that multiple myeloma is predominantly a disease of late adulthood and occurs more frequently in blacks and males. The incidence rate of multiple myeloma has not changed during the 15 years surveyed. The 5-year relative survival rate has remained nearly constant for multiple myeloma. There is a marked difference in 5-year relative survival rates for patients with plasmacytoma of bone marrow (45.7%), multiple myeloma (25.9%), and plasma cell leukemia (13.0%)., Conclusions: Shifts in the relative frequencies of leukemia types may have been affected by changes in classification criteria, changes in the use of histologic terms over time, and the expanded use of immunophenotyping and other technology to characterize acute leukemias. Incidence rates and 5-year relative survival rates for myeloma have remained stable.