Ex vivo expansion with stem cell factor and interleukin-11 augments both short-term recovery posttransplant and the ability to serially transplant marrow

The characterization of many cytokines involved in the control of hematopoiesis has led to intense investigation into their potential use in ex vivo culture to expand progenitor numbers. We have established the optimum ex vivo culture conditions that allow substantial amplification of transient engrafting murine stem cells and which, simultaneously, augment the ability to sustain serial bone marrow transplantation (BMT). Short-term incubation of unfractionated BM cells in liquid culture with stem cell factor (SCF) and interleukin-11 (IL- 11) produced a 50-fold amplification of clonogenic multipotential progenitors (CFU-A). Following such ex vivo expansion, substantially fewer cells were required to rescue lethally irradiated mice. When transplanted in cell doses above threshold for engraftment, BM cells expanded ex vivo resulted in significantly more rapid hematopoietic recovery. In a serial transplantation model, unmanipulated BM was only able to consistently sustain secondary BMT recipients, but BM expanded ex vivo has sustained quaternary BMT recipients that remain alive and well more than 140 days after 4th degree BMT. These results show augmentation of both short-term recovery posttransplant and the ability to serially transplant marrow by preincubation in culture with SCF and IL-11.     

Polymorphism in the LMP2 gene influences susceptibility to extraspinal disease in HLA-B27 positive individuals with ankylosing spondylitis.

OBJECTIVE--To investigate the potential influence of the HLA-linked LMP2 gene on disease susceptibility in HLA-B27 individuals with ankylosing spondylitis (AS). METHODS--A polymorphic CfoI restriction enzyme site in the coding region of the LMP2 gene was evaluated in genomic DNA samples from 193 white and 49 Chinese B27 individuals with well documented AS, 97 of whom had had acute anterior uveitis (AAU) and 97 peripheral arthritis; 42 samples from normal, white, B27 positive blood donors in whom AS was excluded were also evaluated. RESULTS--Analysis of B27 white AS individuals with AAU, peripheral arthritis, or both, revealed significant differences in genotypic distribution of this bi-allelic locus compared with B27 AS patients without extraspinal manifestations (p < 0.005) or B27 controls (p < 0.01). Furthermore, homozygosity for one LMP2 gene allele was significantly more prevalent in AS patients with AAU (71.3%) (p < 0.01) or peripheral arthritis (68.3%) (p < 0.02) than in B27 controls (45.2%). A similar genotypic distribution was noted in B27 Chinese AS individuals with extraspinal manifestations compared with those with axial disease alone. CONCLUSIONS--These findings support the involvement of the HLA linked LMP2 gene in the expression of disease in B27 individuals and represent a novel finding in rheumatic disease.     

Deficiency of platelet membrane glycoprotein Ia associated with a decreased platelet adhesion to subendothelium: a defect in platelet spreading

A bleeding disorder with absent collagen-induced platelet aggregation and adhesion has been described in a patient whose platelets failed to express surface glycoprotein Ia. We studied the interaction of her platelets with subendothelium in an annular perfusion chamber and the interaction with purified human collagen type III in a rectangular perfusion system under flow conditions. Platelet adherence was almost completely absent both at low and high shear rates. The few platelets which adhered remained in the contact stage without subsequent spreading and aggregate formation. Addition of a monoclonal antibody, which was directed against the von Willebrand moiety of FVIII-VWF, to the blood, completely abolished platelet adherence at high shear rates and had a partial effect at low shear rates. These data indicate that von Willebrand factor plays a role in the initial attachment (contact stage) of platelets to subendothelium. We conclude that the bleeding disorder and excessively prolonged bleeding time in our patient are caused by a new specific defect of the platelet-vessel wall interaction.     

High prevalence of symptomatic enthesopathy of the shoulder in ankylosing spondylitis: deltoid origin involvement constitutes a hallmark of disease

OBJECTIVE: To examine the prevalence and characteristics of shoulder involvement in ankylosing spondylitis (AS). To analyze the sensitivity and specificity of shoulder lesions defined by magnetic resonance imaging (MRI) in patients with AS. METHODS: Prevalence of shoulder involvement was ascertained by chart review of 400 AS patients. One hundred of these patients and 285 controls were selected for clinical evaluation. AS patients with a clinically defined shoulder disorder (n = 15) and a control group of 91 patients (94 shoulders) with nonspecific shoulder pain were studied with MRI. Fifty-four MRI-defined variables per shoulder were analyzed by 2 observers. A third cohort of patients with AS (n = 76) was prospectively evaluated by clinical exam for AS-specific shoulder lesions identified on MRI. RESULTS: Shoulder pain was recorded in 3.5% of patients by chart review. Shoulder involvement by clinical evaluation was noted in 24.7% of patients versus 14.2% of controls (odds ratio [OR] 8.17, 95% confidence interval [95% CI] 3.14-21.28, P < 0.001). Rotator cuff tendinitis was significantly more prevalent in patients (15.1%) than controls (3.5%; OR 8.17, 95% CI 2.66-25.14, P < 0.001). Acromioclavicular joint arthrosis was the most common lesion observed in AS shoulders (94%), although specificity was low (32%). Bone marrow edema at any entheseal site was noted in significantly more AS shoulders (70.6%) than in control (19.1%) shoulders (P < 0.001, corrected P = 0.02). Erosion of the greater tuberosity with or without adjacent bone edema had the best combination of sensitivity (58-65%) and specificity (86-92%). Intense acromial entheseal edema at the deltoid origin was observed only in AS shoulders (41.2%; P < 0.001). Evaluation of a prospective cohort of patients with AS showed that 22.4% had rotator cuff enthesopathy. CONCLUSION: Shoulder lesions in AS are common and characterized clinically by rotator cuff tendinitis and on MRI by intense bone edema localized to the supraspinatus/greater tuberosity and deltoid/acromial entheses. Intense acromial bone edema at the deltoid origin is a hitherto undescribed and highly specific feature of AS. Enthesopathy of the rotator cuff is underrecognized in AS and should be incorporated into instruments measuring enthesitis.     

When to image neurologically normal children with headaches: development of a decision rule

Aims: The aim of this study was to develop and refine a decision rule on when to undertake brain imaging (BI) in neurologically normal children with headaches. Methods: From the literature and a questionnaire study, a list of red flags (RFs) was drawn‐up. During the prospective 4‐year period, consecutive children with headache were classified according to RFs and the headache diagnosis. Result: Three of 709 (0.4%) neurologically normal children had significant brain abnormalities. BI was carried out in 389 of 498 (78%) children with RFs. Significant abnormalities were found in three of 389 children (0.8%), all had unclassified headache (UH). BI was not arranged for the 211 children with no RFs. None of these developed RFs or abnormal signs on follow‐up for a mean of 13 months. Conclusion: In addition to BI for those with neurological signs, we think BI should be considered for neurologically normal patients with UH and RFs. This would have saved imaging children needlessly: only 101 of 709 (14%) would have had scans arranged, instead of 389 of 709.     

Systemic hematologic effects of PEG-rHuMGDF-induced megakaryocyte hyperplasia in mice

PEG-rHuMGDF injected daily in normal mice causes a rapid dose-dependent increase in megakaryocytes and platelets. At the same time that platelet numbers are increased, the mean platelet volume (MPV) and platelet distribution width (PDW) can be either decreased, normal, or increased depending on the dose and time after administration. Thus, PEG-rHuMGDF at a low dose causes decreases in MPV and PDW, MGDF at an intermediate dose causes an initial increase followed by a decrease in MPV and PDW, and PEG-rHuMGDF at higher doses causes an increase in MPV and PDW followed by a gradual normalization of these platelet indices. In addition to the expected thrombocytosis after 7 to 10 days of daily injection of high doses of PEG-rHuMGDF, a transient decrease in peripheral red blood cell numbers and hemoglobin is noted accompanied in the bone marrow by megakaryocytic hyperplasia, myeloid hyperplasia, erythroid and lymphoid hypoplasia, and deposition of a fine network of reticulin fibers. Splenomegaly, an increase in splenic megakaryocytes, and extramedullary hematopoiesis accompany the hematologic changes in the peripheral blood and marrow to complete a spectrum of pathologic features similar to those reported in patients with myelofibrosis and megakaryocyte hyperplasia. However, all the PEG-rHuMGDF-initiated hematopathology including the increase in marrow reticulin is completely and rapidly reversible upon the cessation of administration of PEG-rHuMGDF. Thus, transient hyperplastic proliferation of megakaryocytes does not cause irreversible tissue injury. Furthermore, PEG-rHuMGDF completely ameliorates carboplatin-induced thrombocytopenia at a low-dose that does not cause the hematopathology associated with myelofibrosis.     

Aortopulmonary window lesions: detection with chest radiography

A retrospective morphologic study of 80 cases was undertaken to determine factors affecting detectability of computed tomographically (CT) proved aortopulmonary (AP) window lesions on conventional posteroanterior (PA) and lateral chest radiographs. Criteria used for determining abnormality were: solitary lymph node enlargement over 1.5 cm or three or more 1-cm nodes and obvious large masses or vascular anomalies. CT scans and corresponding PA and lateral radiographs were analyzed for lesion detectability, size, and location. In 49% of cases there was no detectable lesion in the AP window on radiographs; a definite AP window lesion was seen in 41%, and 10% were equivocal. Major contributing factors to low detectability of AP window lesions on radiographs include size and, more important, location of the lesion. An additional 45 cases of CT-proved normal AP windows were retrospectively reviewed to determine the false-positive rate of PA and lateral radiographs in detection of AP window lesions: 43 (96%) were classified as negative, the remaining two (4%) as equivocal. Although the AP window is a small space, it is the site of many pathologic conditions; the study results indicate that CT may be an essential procedure for its evaluation.     

Colorectal neoplasms: accuracy of US in demonstrating the depth of invasion

Six normal and 16 neoplastic colorectal specimens were examined with 8.5-MHz ultrasound (US). An articulated system facilitated precise spatial correlation between US and histologic sections. Images were blindly interpreted and then compared with histologic results. All six normal specimen showed five distinct echo layers and were distinguished from neoplastic specimens by all the observers. The central echogenic layer, corresponding to the submucosa, is useful in determining the depth of origin of a neoplasm and the presence of submucosal invasion. US had an accuracy of 92.5% in demonstrating invasion of the submucosa and 77% for invasion of the muscularis externa. For mucosal neoplasms with invasion through the muscularis externa and extension into the subserosal tissues, nearly 90% of US interpretations were correct. High-frequency US may be useful in determining the depth of invasion of mucosal tumors with respect to the submucosa and in differentiating mucosal from extramural masses.     

Allelic variation at the TAP 1 locus influences disease phenotype in HLA-B27 positive individuals with ankylosing spondylitis

Abstract: The objective was to determine the role of the TAP 1 gene in influencing the phenotype of disease in adult patients with ankylosing spondylitis (AS). The distribution of TAP 1 gene alleles was determined using the PCR RFLP method and restriction enzymes Bcl I and Ace I. The study population included 115 HLA-B27 positive patients with well-documented AS and 41 HLA-B27 positive normal controls. No significant difference in distribution of TAP 1 alleles was noted in comparisons of all AS patients with normal controls. However, AS patients with extraspinal disease were noted to have a significantly increased prevalence of the TAP 1B allele (17.0%) as compared to AS patients without extraspinal disease (2.9%) (P=0.005) or normal controls (1.9%) (P=0.005). Polymorphism at the TAP 1 locus may influence disease outcome in patients with AS.