Artificial intelligence-based recurrence prediction outperforms classical histopathological methods in pulmonary adenocarcinoma biopsies

INTRODUCTION

Between 10 and 50% of early-stage lung adenocarcinoma patients experience local or distant recurrence. Histological parameters such as a solid or micropapillary growth pattern are well-described risk factors for recurrence. However, not every patient presenting with such a pattern will develop recurrence. Designing a model which can more accurately predict recurrence on small biopsy samples can aid the stratification of patients for surgery, (neo-)adjuvant therapy, and follow-up.

MATERIAL AND METHODS

In this study, a statistical model on biopsies fed with histological data from early and advanced-stage lung adenocarcinomas was developed to predict recurrence after surgical resection. Additionally, a convolutional neural network (CNN)-based artificial intelligence (AI) classification model, named AI-based Lung Adenocarcinoma Recurrence Predictor (AILARP), was trained to predict recurrence, with an ImageNet pre-trained EfficientNet that was fine-tuned on lung adenocarcinoma biopsies using transfer learning. Both models were validated using the same biopsy dataset to ensure that an accurate comparison was demonstrated.

RESULTS

The statistical model had an accuracy of 0.49 for all patients when using histology data only. The AI classification model yielded a test accuracy of 0.70 and 0.82 and an area under the curve (AUC) of 0.74 and 0.87 on patch-wise and patient-wise hematoxylin and eosin (H&E) stained whole slide images (WSIs), respectively.

CONCLUSION

AI classification outperformed the traditional clinical approach for recurrence prediction on biopsies by a fair margin. The AI classifier may stratify patients according to their recurrence risk, based only on small biopsies. This model warrants validation in a larger lung biopsy cohort.

The value of prognostic and predictive parameters in early-stage lung adenocarcinomas: A comparison between biopsies and resections

INTRODUCTION

Since lung adenocarcinoma (LUAD) biopsies are usually small, it is questionable if their prognostic and predictive information is comparable to what is offered by large resection specimens. This study compares LUAD biopsies and resection specimens for their ability to provide prognostic and predictive parameters.

METHODS

We selected 187 biopsy specimens with stage I and II LUAD. In 123 cases, subsequent resection specimens were also available. All specimens were evaluated for growth pattern, nuclear grade, fibrosis, inflammation, and genomic alterations. Findings were compared using non-parametric testing for categorical variables. Model performance was assessed using the area under the curve for both biopsies and resection specimens, and overall (OS) and disease-free survival (DFS) was calculated.

RESULTS

The overall growth pattern concordance between biopsies and resections was 73.9%. The dominant growth pattern correlated with OS and DFS in resected adenocarcinomas and for high-grade growth pattern in biopsies. Multivariate analysis of biopsy specimens revealed that T2-tumors, N1-status, KRAS mutations and a lack of other driver mutations were associated with poorer survival. Model performance using clinical, histological and genetic data from biopsy specimens for predicting OS and DSF demonstrated an AUC of 0.72 and 0.69, respectively.

CONCLUSIONS

Our data demonstrated the prognostic relevance of a high-grade growth pattern in biopsy specimens of LUAD. Combining clinical, histological and genetic information in one model demonstrated a suboptimal performance for DFS prediction and good performance for OS prediction. However, for daily practice, more robust (bio)markers are required to predict prognosis and stratify patients for therapy and follow-up.

Delayed hematopoietic recovery after auto-SCT in patients receiving arsenic trioxide-based therapy for acute promyelocytic leukemia: a multi-center analysis

A potential link between arsenic (ATO)-based therapy and delayed hematopoietic recovery after autologous hematopoietic SCT (HSCT) for acute promyelocytic leukemia (APL) has previously been reported. We retrospectively reviewed the clinical histories of 58 patients undergoing autologous HSCT for APL at 21 institutions in the United States and Japan. Thirty-three (56%) of the patients received ATO-based therapy prior to stem cell collection. Delayed neutrophil engraftment occurred in 10 patients (17%): 9 of the 10 patients (90%) received prior ATO (representing 27% of all ATO-treated patients), compared with 1 of the 10 patients (10%) not previously treated with ATO (representing 4% of all ATO-naïve patients; P<0.001). Compared with ATO-naïve patients, ATO-treated patients experienced significantly longer times to ANC recovery (median 12 days vs 9 days, P<0.001). In multivariate analysis, the only significant independent predictor of delayed neutrophil engraftment was prior treatment with ATO (hazard ratio 4.87; P<0.001). Of the available stem cell aliquots from APL patients, the median viable post-thaw CD34+ cell recovery was significantly lower than that of cryopreserved autologous stem cell products from patients with non-APL AML. Our findings suggest that ATO exposure prior to CD34+ cell harvest has deleterious effects on hematopoietic recovery after autologous HSCT.

Bortezomib, dexamethasone, cyclophosphamide and lenalidomide combination for newly diagnosed multiple myeloma: phase 1 results from the multicenter EVOLUTION study

This phase 1 study (Clinicaltrials.gov: NCT00507442) was conducted to determine the maximum tolerated dose (MTD) of cyclophosphamide in combination with bortezomib, dexamethasone and lenalidomide (VDCR) and to assess the safety and efficacy of this combination in untreated multiple myeloma patients. Cohorts of three to six patients received a cyclophosphamide dosage of 100, 200, 300, 400 or 500 mg/m(2) (on days 1 and 8) plus bortezomib 1.3 mg/m(2) (on days 1, 4, 8 and 11), dexamethasone 40 mg (on days 1, 8 and 15) and lenalidomide 15 mg (on days 1-14), for eight 21-day induction cycles, followed by four 42-day maintenance cycles (bortezomib 1.3 mg/m(2), on days 1, 8, 15 and 22). The MTD was the cyclophosphamide dose below which more than one of six patients experienced a dose-limiting toxicity (DLT). Twenty-five patients were treated. Two DLTs were seen, of grade 4 febrile neutropenia (cyclophosphamide 400 mg/m(2)) and grade 4 herpes zoster despite anti-viral prophylaxis (cyclophosphamide 500 mg/m(2)). No cumulative hematological toxicity or thromboembolic episodes were reported. The overall response rate was 96%, including 20% stringent complete response (CR), 40% CR/near-complete response and 68% >or=very good partial response. VDCR is well tolerated and highly active in this population. No MTD was reached; the recommended phase 2 cyclophosphamide dose in VDCR is 500 mg/m(2), which was the highest dose tested.

Utility of bortezomib retreatment among patients with refractory multiple myeloma

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Background: Bortezomib (VELCADE; Vc) has emerged as the standard of care for patients with relapsed or refractory multiple myeloma (MM). However, following initial Vc therapy, its utility in recurrent disease is unclear. This retrospective case series provides preliminary evidence of the safety and efficacy of Vc in the retreatment of patients with recurrent MM. Methods: An observational case series was developed based on a medical records review of all patients (N = 10) who completed Vc retreatment following completion of initial Vc therapy. Best response was measured as the greatest mean % reduction in the treatment response measure: serum/urine M-protein or plasma cells. Differences between initial treatment and retreatment efficacy and Vc-related hospitalizations were assessed using descriptive statistics. Results: During initial treatment 44% of patients responded to Vc (≥50% M-protein (3/9) or plasme cell reduction (1/9, 1 pt NA). At retreatment 50% of patients responded (5/10). Following initial Vc therapy, the median treatment-free interval was just over 13 months (56.6 weeks). One patient experienced a dose reduction due to peripheral neuropathy (grade 2) during retreatment, compared to two patients with neuropathy (grade 3) during initial treatment. Termination of therapy due to any unmanageable toxicity was much lower during retreatment (14.3% vs 62.5%). Finally, none of the patients were hospitalized for Vc-related events during retreatment, compared with two patients during initial treatment. Conclusions: Vc retreatment appears to be as effective as initial treatment in terms of response, and may actually yield less toxicity and hospitalizations. Even though this small sample size precluded statistical testing, the observed patterns are instructive and additional prospective trials are currently ongoing. However, based on these preliminary data, prolonged disease control may be achieved with repeated use.

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Autologous stem cell transplantation for advanced acute myeloid leukemia

We studied the efficacy of a two-step approach to autologous stem cell transplantation for patients with advanced acute myeloid leukemia. Step 1 consisted of consolidation chemotherapy using cytarabine 2000 mg/m(2) twice daily for 4 days plus etoposide 40 mg/kg by continuous infusion over the same 4 days. Peripheral blood stem cells were collected under granulocyte colony-stimulating factor (G-CSF) stimulation during recovery from this chemotherapy. Step 2, autologous stem cell transplantation, utilized the preparative regimen of oral busulfan 16 mg/kg followed by etoposide 60 mg/kg i.v. During step 1, there were no treatment-related deaths among 28 patients, but two patients did not proceed to transplantation because of failure of mobilization. A median CD34+ dose (x10(6)/kg) of 13.6 was collected. Of 26 patients undergoing autologous transplant, there was one treatment-related death and 12 relapses. With a median follow-up of 5.4 years, 5 year event-free survival (EFS) of all patients entered is 54%. The most important prognostic factor was cytogenetic changes. All seven patients with t(15,17) remained in long-term remission whereas EFS for other patients was 38%. We conclude that this two-step approach to autologous transplantation produces excellent stem cell yields, allows a high percentage of patients to receive the intended therapy, and provides effective treatment.

Management issues in women with inflammatory bowel disease

Medical practitioners caring for women with inflammatory bowel disease should recognize that gender may have a profound influence on patient perception of disease, body image, and clinical symptoms. These gender-related concerns as well as issues such as fertility and pregnancy increase the complexity of medical and surgical management of women with inflammatory bowel disease. This article reviews the important issues for practitioners to consider in taking care of women with ulcerative colitis and Crohn's disease, focusing especially on body image, fertility, management of disease during pregnancy, and osteoporosis.

High-dose chemotherapy and hematopoietic stem cell rescue for breast cancer: experience in California

The role of high-dose chemotherapy (HDCT) and autologous hematopoietic stem cell rescue in breast cancer is still controversial. We analyzed the outcomes of 1111 consecutive patients with histologically proven breast cancer who underwent HDCT at 5 major California medical centers. The overall treatment-related mortality (TRM) was 2.3%. TRM was not influenced by disease stage or the HDCT regimen delivered, but it was influenced by hematopoietic graft source. The TRM was 6.1% when bone marrow with or without blood stem cells was used, but only 1.4% when blood stem cells alone were used (P < .001). With a median follow-up of 2.8 years (range, 0.1-8.2 years) after HDCT and autologous hematopoietic stem cell rescue, the estimated 5-year event-free survival (EFS) and overall survival (OS) for stage II/IIIA patients with > or =10 involved axillary lymph nodes were 67% and 76%, respectively. Patients with metastatic breast cancer (MBC) (median follow-up, 1.9 years [range, 0.03-8.3 years]) achieving a complete response (CR) to conventional-dose chemotherapy or rendered to a "no evidence of disease" status before HDCT had significantly better estimated 5-year EFS and OS (28% and 57%, respectively) than those achieving a partial response before HDCT (19% and 27%, respectively; P < or = .0001). Our data suggest that HDCT with hematopoietic stem cell rescue is safe and can be beneficial to patients with high-risk primary breast cancer and for those with MBC achieving CR/no evidence of disease.

Pharmacokinetics and safety of an anti-vascular endothelial growth factor aptamer (NX1838) following injection into the vitreous humor of rhesus monkeys

PURPOSE

The objective of this study was to determine the pharmacokinetics and safety for NX1838 following injection into the vitreous humor of rhesus monkeys.

METHODS

Plasma and vitreous humor pharmacokinetics were determined following a single bilateral 0.25, 0.50, 1.0, 1.5, or 2.0 mg/eye dose. In addition, the pharmacokinetics and toxicological properties of NX1838 were determined following six biweekly bilateral injections of 0.25 or 0.50 mg/eye or following four biweekly bilateral injections of 0.10 mg per eye followed by two biweekly bilateral injections of 1.0 mg per eye.

RESULTS

Plasma and vitreous humor NX1838 concentrations were linearly related to the dose administered. NX1838 was cleared intact from the vitreous humor into the plasma with a half-life of approximately 94 h, which was in agreement with the plasma terminal half-life. Vascular endothelial growth factor (VEGF)-binding assays demonstrated that the NX1838 remaining in the vitreous humor after 28 days was fully active. No toxicological effects or antibody responses were evident.

CONCLUSIONS

The no observable effect level was greater than six biweekly bilateral 0.50 mg/eye doses or two biweekly bilateral 1.0 mg/eye doses. These pharmacokinetic and safety data support monthly 1 or 2 mg/eye dose regimens in human clinical trials.

Trisomy 4 and double minutes in acute myeloid leukemia: further evidence that double minutes can occur as the primary cytogenetic abnormality

The specific association of trisomy 4 and double minutes (dmin) is rare and is usually reported in patients with acute myeloid leukemia (AML), primarily M2 and M4 subtypes. Several previous reports describing this combination suggested that trisomy 4 was the primary cytogenetic abnormality, and that the presence of the dmin was secondary. We describe a 79-year-old male who presented with myelodysplasia, transforming to AML-M2. Cytogenetic analysis of bone marrow aspirate cultures showed a 46,XY,dmin[12]/47,XY,+4,dmin[7]/46, XY[6] karyotype. The number of dmin ranged from 1 to 150. Fluorescence in situ hybridization (FISH) analysis showed that the dmin were derived from amplification of the MYC oncogene. Dual-color interphase FISH analysis was performed with D4Z1 and MYC probes and showed no evidence of a clone containing trisomy 4 without dmin. These data suggest that dmin may also occur as the primary cytogenetic abnormality in patients with trisomy 4 and dmin.

High-dose chemotherapy (CTM) for breast cancer

We designed and implemented a new mitoxantrone-based high-dose chemotherapy regimen to minimize pulmonary injury (seen in carmustine-based regimens) in patients with breast cancer. One hundred and ninety-one breast cancer patients (99 stage II/IIIA; 27 stage IIIB; 65 stage IV responsive to conventional-dose chemotherapy) were treated with high-dose chemotherapy (CTM) delivered over 4 days (cyclophosphamide (6 g/m2), thiotepa (600 mg/m2), and mitoxantrone (24-60 mg/m2)) followed by autologous hematopoietic stem cell rescue. Stage II/III patients received chest wall radiation and tamoxifen (if hormone-receptor positive) after CTM. The 5-year event-free survival (EFS) for stage II/IIIA patients with 10 or more involved axillary lymph nodes (n = 80) was 62 +/- 12%. Hormone receptor-positive patients with 10 or more nodes did significantly better than negative patients. The EFS for stage IIIB patients at 5 years was 44 +/- 19%; for stage IV patients at 5 years was 17 +/- 10%. Stage IV patients achieving complete response in viscera and/or soft tissue prior to CTM did significantly better than those achieving a partial response. There were six (3%) treatment-related deaths including two due to diffuse alveolar hemorrhage. There were no episodes of delayed interstitial pneumonitis. There were six severe cardiac events in 91 patients (6.6%) but none after instituting mitoxantrone dose-adjustment in the final 100 patients. We conclude that CTM is associated with a low treatment-related mortality and little pulmonary toxicity. CTM produces excellent outcomes in stage II/IIIA patients with 10 or more involved axillary lymph nodes.

Monosomy 16 as the sole abnormality in myeloid malignancies

The majority of acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) patients reported with chromosome 16 abnormalities had the inv(16)(p13q22) or t(16;16)(p13;q22) rearrangements, which were associated with a favorable prognosis. In contrast, del(16)(q22) was reported less commonly but was associated with a less favorable prognosis. We describe an 80-year-old woman who presented with MDS (refractory anemia). Chromosome analysis from bone marrow aspirate cultures showed monosomy 16 as the sole cytogenetic abnormality. Comparison of this patient with previously reported cases of monosomy 16 showed that this uncommon abnormality was associated with myeloid disorders. Monosomy 16 patients, similar to del(16)(q22) patients, tended to be elderly, presented with MDS or AML, and had a poor prognosis. The similarity in clinical course for del(16)(q22) and monosomy 16 patients suggests that the phenotype in both groups resulted from loss of important gene(s) on 16q, as distinct from the fusion gene product identified in the inv(16) and t(16;16) rearrangements.

An evaluation of the toxicities of 2'-fluorouridine and 2'-fluorocytidine-HCl in F344 rats and woodchucks (Marmota monax)

The toxicities of 2'-fluorouridine (2'-FU) and 2'-fluorocytidine-HCl (2'-FC) were separately evaluated in 2 species, male Fischer 344 (F334) rats and woodchucks. Particular attention was focused on the ability of these nucleosides to induce toxicities similar to those induced by the antiviral drug fialuridine (FIAU). 2'-FU or 2'-FC was administered to F344 male rats by intravenous injection at doses of 5, 50, and 500 mg/kg/day for 90 consecutive days and to male and female woodchucks at doses of 0.75 and 7.5 mg/kg/day for 90 consecutive days. Clinical chemistry, hematology, and urinalysis (woodchuck only) profiles were assessed during and at the termination of the study. At necropsy, organs were weighed and tissues collected for routine histologic analysis. Cytochrome c oxidase activity, citrate synthase activity, and mitochondrial DNA content were measured, and micronucleus formation in the bone marrow (rats only) was evaluated. No adverse clinical effects were observed in either species. Rats treated with high doses of either 2'-FU or 2'-FC had body weights that were 90% of those of controls. 2'-FU and 2'-FC both induced a moderate decrease in the median lymphocyte count, and 2'-FC and 2'-FU induced a mild increase in mean corpuscular hemoglobin and mean corpuscular volume. Both compounds caused slight to moderate, reversible, histologic changes in the spleen and thymus. In the woodchuck, 2'-FC caused a slight increase in mean absolute lymphocytes, and 2'-FC and 2'-FU slightly increased hepatic periportal vacuolation and/or mononuclear cell infiltration. In summary, neither compound showed evidence of the toxicity induced by fialuridine in either species. Although compound effects were observed, none of these effects were considered to be adverse, and the no-observed adverse effect level was determined to be 500 mg/kg/day for both compounds in the male F344 rat and 7.5 mg/kg/day in the woodchuck.

Autologous bone marrow transplantation for acute myeloid leukemia using 4-hydroperoxycyclophosphamide-purged bone marrow and the busulfan/etoposide preparative regimen: a follow-up report

We studied the use of autologous bone marrow transplantation (ABMT) as treatment for acute myeloid leukemia (AML) in adults up to age 60. We used a preparative regimen of busulfan 16 mg/kg plus etoposide 60 mg/kg and bone marrow purged with 100 microg/ml of 4-hydroperoxycyclophosphamide (4HC). We treated 50 first remission patients; there were two treatment-related deaths and 13 relapses. With median follow-up of 6.8 years (minimum 4.5) disease-free survival (DFS) is 70%, relapse rate 27% and overall survival 72%. Patients with favorable cytogenetics had DFS 78% and relapse 18% whereas unfavorable patients had DFS 63% and relapse rate 35%. For 25 patients in second or third remission there were five treatment-related deaths and seven relapses. DFS is 52% and relapse rate 35%. None of six patients with primary refractory AML had long-term disease control. These data support the use of ABMT with an intensive preparative regimen and purged bone marrow as a highly effective treatment for adults with AML.

Mismatches for two major and one minor histocompatibility antigen correlate with a patient's rejection of a bone marrow graft from a serologically HLA-identical sibling

We describe the case of a patient with chronic myeloid leukemia who rejected a bone marrow (BM) graft from a sibling donor believed to be HLA identical. Sequencing of the HLA genes showed the mother to be heterozygous for two closely related HLA haplotypes that could not be resolved by serological typing. The donor and the recipient had each inherited a different maternal haplotype resulting in allelic mismatches for the HLA-B35 and the HLA-DR11 genes. T cell cytotoxicity directed towards the donor's B35 allele was detected in the patient, in addition to CTL specificity for an HLA-B7-restricted minor histocompatibility antigen carried by the donor, resulting in three histocompatibility mismatches between the BM donor and the recipient.

Liver disease in pregnancy

The liver is one of the many organs affected by the physiologic and hormonal changes that occur during pregnancy. Hepatic disorders diagnosed before pregnancy may be unaffected or exacerbated by the pregnant state. Liver disorders that are specific to pregnancy, including hyperemesis gravidarum, intrahepatic cholestasis of pregnancy, acute fatty liver of pregnancy, preeclampsia/ eclampsia, HELLP, and hepatic rupture, may have a profound impact on the morbidity and mortality rates of mother and fetus. Although an unequivocal diagnosis is often difficult to make, it should be attempted in a timely manner so that optimal treatment can be determined. After the diagnosis is made, maximizing the health of the mother and fetus determines future management.

Gastroesophageal reflux in pregnancy

Gastroesophageal reflux symptoms are common in pregnancy, occurring in approximately 45% to 80% of gravid women. Although the symptoms associated with reflux in pregnancy are similar to those described in the nongravid state, some of the etiologies are distinct due to hormonal fluctuations and other physiologic changes often associated with pregnancy. Diagnostic tools and therapeutic regimens that might be used without hesitation in the nonpregnant patient must be given cautious consideration in the gravid patient due to potential fetal risks. This article addresses the epidemiology, pathophysiology, diagnosis, and treatment of gastroesophageal reflux in pregnancy.

Busulfan plus etoposide as a preparative regimen for autologous bone marrow transplantation for acute myelogenous leukemia: an update

We have used a new preparative regimen prior to autologous bone marrow transplantation in patients in remission of acute myelogenous leukemia (AML). Sixty-two patients were treated with preparative chemotherapy consisting of 1 mg/kg of busulfan every 6 hours for 4 days (total dose 16 mg/kg) on days -7 to -4 followed by an intravenous infusion of 60 mg/kg of etoposide on day -3. Autologous bone marrow that had been purged with 4-hydroperoxycyclophosphamide was infused on day 0. Thirty-five of the treated patients were in first remission, 21 were in second or third remission, and six had primary refractory AML and required aggressive salvage regimens to achieve remission. Among patients in first remission, one treatment-related death and five relapses have occurred. With a median follow-up of 25 months, the actuarial relapse rate is 19% +/- 8% and the disease-free survival rate is 79% +/- 8% at 3 years. The 16 patients with favorable FAB subtypes (M3 or M4E0) showed an excellent response to this treatment protocol, with no relapses after median follow-up of 35 months. Among patients in second or third remission, there were five treatment-related deaths and five relapses. With a median follow-up of 41 months, the actuarial relapse rate is 30% +/- 11% and the disease-free survival rate is 52% +/- 11% at 3 years. Four of six primary refractory patients died during treatment and one remains in remission with short follow-up. These preliminary data indicate that aggressive preparative regimens followed by the infusion of purged autologous bone marrow may be a promising approach to improving the clinical outcome of adult patients with AML.

Autologous bone marrow transplantation for acute myeloid leukemia using busulfan plus etoposide as a preparative regimen

We have studied the use of a new preparative regimen for the treatment of patients in remission of acute myeloid leukemia (AML) with autologous bone marrow transplantation. Chemotherapy consisted of busulfan 1 mg/kg every 6 hours for 4 days (total dose, 16 mg/kg) on days -7 through -4 followed by an intravenous infusion over 6 to 10 hours of etoposide 60 mg/kg on day -3. Autologous bone marrow, treated in vitro with 100 micrograms/mL of 4-hydroperoxycyclophosphamide, was infused on day 0. We have treated 58 patients up to the age of 60 years, 32 in first remission, 21 in second or third remission, and 5 with primary refractory AML unresponsive to high-dose Ara-C, but achieving remission with aggressive salvage regimens. Of the first remission patients, there has been 1 treatment related death and 5 relapses. With median follow-up of 22 months, the actuarial relapse rate is 22% +/- 9% and disease-free survival is 76% +/- 9% at 3 years. Patients with favorable French-American-British (FAB) subtypes (M3 or M4 EO) did especially well, with no relapses seen in 15 patients observed for a median of 30 months. Actuarial relapse rate at 3 years was 48% for first remission patients with less favorable FAB subtypes. Of patients in second or third remission, there were 5 treatment related deaths and 4 relapses. With median follow-up of 22 months, the actuarial relapse rate is 25% +/- 11% and disease-free survival is 56% +/- 11% at 3 years. Four of five primary refractory patients died during treatment and 1 remains in remission with short follow-up. These preliminary data are very encouraging and, if confirmed, support the use of autologous purged bone marrow transplantation using aggressive preparative regimens as one approach to improve the outcome of adults with AML.

Pharmacologic characterization of the rabbit neutrophil receptor for platelet-activating factor

The characteristics of receptors for platelet-activating factor (PAF) on rabbit neutrophils are investigated in this report. The presence of PAF-specific binding to rabbit neutrophils was confirmed using radiolabeled ligand binding assays and a rabbit peritoneal neutrophil membrane preparation. Binding of PAF to the neutrophil membranes was reversible and reached equilibrium within 30 min. Scatchard analysis of PAF-specific binding to the rabbit neutrophil membranes revealed a dissociation constant (Kd) for PAF of 0.41 +/- 0.045 nM and a Bmax of 0.32 +/- 0.11 pmol of PAF receptor/mg of protein. The order of potencies of PAF receptor antagonists to inhibit the binding of 3H-PAF to rabbit peritoneal neutrophil membranes was determined. For the competition assays, 100 micrograms of neutrophil or platelet membrane protein, 0.18 nM 3H-PAF, and varying amounts of PAF antagonist were incubated at room temperature for 1 hr. PAF receptor antagonists tested were ONO-6240, brotizolam, kadsurenone, WEB-2086, L-652-731, BN-52021, CV-3988, triazolam, alprazolam, and verapamil. The orders of potencies of these PAF receptor antagonists were similar for inhibition of 3H-PAF binding to rabbit peritoneal neutrophil and platelet membranes (correlation coefficient, r = 0.97). PAF had a significantly higher affinity for rabbit neutrophil membranes (Kd = 0.41 +/- 0.045 nM), as compared with its affinity for rabbit platelet membranes (Kd = 0.87 +/- 0.092 nM). In addition, sodium was found to inhibit 3H-PAF specific binding to rabbit platelet membranes and not to affect 3H-PAF binding to neutrophil membranes. These data indicate that, although PAF receptors on rabbit platelets and neutrophils exhibit similar orders of potencies of PAF receptor antagonists to inhibit the binding of 3H-PAF, the disparity in Kd of PAF for the receptors and the effect of NaCl on the binding of 3H-PAF reveal subtle differences between the cell types.

Intraluminal proteolytic activation plays an important role in replication of type 1 reovirus in the intestines of neonatal mice

Oral inoculation of suckling mice with reovirus serotype 1 (strain Lang) results in the conversion of intact virions to intermediate subviral particles (ISVPs) in the intestinal lumen. Digestion of virus in vitro with chymotrypsin or trypsin reveals two distinct forms of ISVPs, while the predominant species of ISVPs found in the small intestinal lumen appears to be identical to the chymotrypsin product. The in vivo conversion of virions to ISVPs was blocked by pretreatment of mice with protease inhibitors, resulting in inefficient replication of reovirus in intestinal tissue. The early inhibition of viral replication in suckling mice pretreated with protease inhibitors was not observed when suckling mice were inoculated with ISVPs generated by in vitro digestion with either chymotrypsin or trypsin. However, replication was decreased during secondary rounds of replication in mice receiving repeated doses of protease inhibitors, suggesting that luminal proteolytic digestion is important in rendering progeny virions infectious in the gut.

Deficiency of protein 4.2 in erythrocytes from a patient with a Coombs negative hemolytic anemia. Evidence for a role of protein 4.2 in stabilizing ankyrin on the membrane

A patient with a mild hemolytic anemia and osmotically fragile, spherocytic erythrocytes was studied. Analysis of the erythrocyte membrane proteins by SDS-PAGE revealed a deficiency of protein 4.2 (less than 0.10% of normal). The protein 4.2-deficient erythrocytes contained normal amounts of all other membrane proteins, although the amount of band 3 was slightly reduced and the amount of band 6 (G3PD) was slightly elevated. The spectrin content of these cells was normal, as measured by both SDS-PAGE and radioimmunoassay. Erythrocytes from the patient's biologic parents were hematologically normal and contained normal amounts of protein 4.2. Immunological analysis using affinity purified antibodies revealed that the patient's protein 4.2 was composed of equal amounts of a 74-kD and 72-kD protein doublet, whereas the normal protein was composed primarily of a 72-kD monomer. Proteolytic digestion studies using trypsin, alpha-chymotrypsin and papain demonstrated that the patient's protein 4.2 was similar but not identical to the normal protein. Binding studies showed that the protein 4.2-deficient membranes bound purified protein 4.2 to the same extent as normal membranes, suggesting that the membrane binding site(s) for the protein were normal. Depleting the protein 4.2-deficient membranes of spectrin and actin resulted in a loss of nearly two-thirds of the membrane ankyrin, whereas similar depletion of normal membranes resulted in no loss of ankyrin. Repletion of the protein 4.2-deficient membranes with purified protein 4.2 before spectrin-actin extraction partially prevented the loss of ankyrin. These results suggest that protein 4.2 may function to stabilize ankyrin on the erythrocyte membrane.

Reovirus type I infection of small intestinal epithelium in suckling mice and its effect on M cells

In 10-day-old mice, reovirus serotype I (reo I) selectively adheres to the apical surface of M cells and penetrates the intestinal epithelium via M cells overlying Peyer's patches before causing disseminated infection. Recently, reo I enteritis has been described in adult mice. We wished to determine if reo I enteritis also occurs in suckling mice and, if so, to determine which major epithelial cell types become infected and where the virus enters epithelial cells other than M cells. Transmission electron microscopy revealed that after oral inoculation of 10-day-old mice, peak infection of M cells preceded that of absorptive and undifferentiated crypt cells. The percentage of M cells in the dome epithelial cell population was reduced more than 4-fold between 4 and 72 hours after reo I inoculation compared with saline-inoculated mice. By 6 days after inoculation, reo I replication was no longer observed and there was a more than 2-fold increase in M cells overlying Peyer's patches domes of reo I-inoculated mice compared with saline controls. By 13 days, control and infected mice had similar percentages of M cells. When incubated with isolated intestinal epithelial sheets, reo I adhered selectively to and was endocytosed via the basal plasma membrane of absorptive cells. Thus, reo I initially penetrates the intestinal epithelium via the apical surface of M cells which become infected. Virions subsequently enter absorptive and crypt cells via their basal surfaces. During the first 3 days of enteritis, the M cell population becomes markedly depleted which may affect the permeability of the mucosal barrier to microorganisms and other antigens as well as influence the host immune response.

Adherence to and penetration of the intestinal epithelium by reovirus type 1 in neonatal mice

In 10-day-old suckling and adult mice, reovirus type 1 adheres selectively to and penetrates membranous epithelial (M) cells. To determine when M cells first appear, when they first transport reovirus, and if reovirus adheres to and is endocytosed by other epithelial cells in the first postnatal week, we examined neonatal mouse intestine by transmission electron microscopy after reovirus type 1 exposure. At 2 days M cells accounted for 0.9% of dome epithelial cells. By 9 days M cells had increased to 7.4%. Reovirus type 1 adherence to the surface of villus and dome epithelial cells showed marked variation in 2-6-day-old animals, but by 7 days only a few absorptive cell profiles had adherent reovirus. Adherence to greater than 50% of M-cell profiles occurred in all but 2 animals, but adherence to the majority of Peyer's patch absorptive cell profiles was present only in some 4- and 5-day-old animals. Adherence to a majority of undifferentiated cell profiles occurred in some animals at all ages. Membranous epithelial cells endocytosed reovirus at all ages but only at 2 days did rare villus and dome absorptive cells endocytose reovirus into the apical cytoplasm. Thus, adherence of reovirus to the apical surface of mucosal epithelial cells is nonselective in newborn mice but becomes more selective within the first postnatal week with adherence by day 7 to most M-cell profiles, to a substantial but variable number of undifferentiated cell profiles, but to few absorptive cell profiles.

The membranous epithelial (M) cell and the mucosal immune system

Membranous epithelial (M) cells are specialized epithelial cells overlying the subepithelial lymphoid follicles in the gastrointestinal and respiratory tracts. Antigens, including some viruses and bacteria, penetrate the mucosal barrier via the M cell, which endocytoses and transports antigens and microorganisms into the Peyer's patch or bronchial-associated lymphoid tissue. Here antigens may initiate an immune response and/or disseminate and induce disease. This review discusses the structure and function of the M cell, its role in macromolecular uptake, and its interaction with the immune system.

Outcome of bone marrow transplantation in patients with extramedullary involvement of acute leukemia

Infiltration of extrahemopoietic tissue with leukemic cells was evaluated as a prognostic indicator in 18 patients with acute leukemia undergoing bone marrow transplantation. When compared to 107 patients who did not have extramedullary leukemia at any time prior to marrow grafting, the patients with leukemic invasion into organs outside the hemopoietic system had a significant increase of leukemic recurrence and a significant decrease in survival after marrow transplantation. Extramedullary leukemia may be a negative prognostic indicator for bone marrow transplantation candidates.

Determinants of reovirus interaction with the intestinal M cells and absorptive cells of murine intestine

Reovirus type 1 penetrates the gastrointestinal tract in suckling mice via specialized epithelial cells, designated membranous cells, or M cells, located in the epithelium overlying Peyer's patches. We have examined whether the interaction of reovirus with murine mucosa of in situ closed ileal loops is influenced by mouse age or strain or reovirus serotype. Neither mouse age (suckling or adult), strain (C3H/HeJ or Balb/cJ), nor reovirus serotype (types 1 and 3) affected reovirus adherence to and transport through M cells. In all conditions, reovirions adhered to the M-cell surface and were transported across M cells in endocytic vesicles. The adherence to and endocytosis by M cells of type 1 reovirus and reassortants with the viral hemagglutinin of type 1 were selective in suckling mice; type 1 virus was not adherent to nor endocytosed by absorptive cells. In adult mice, type 1 reovirions adhered to the surface of a minority of absorptive cells but were never seen within absorptive cell cytoplasm. In contrast, type 3 reovirus and reassortants with the viral hemagglutinin of type 3 adhered to and were endocytosed not only by M cells but also by absorptive cells of suckling mice. Virions accumulated within lysosomelike bodies in absorptive cells but transport of virions across absorptive cells was not observed. These studies indicate that (a) adherence of reovirus to the apical surface of and transcellular transport by M cells is independent of viral serotype or viral surface proteins, (b) adherence of reovirus to and transcellular transport by M cells is independent of mouse age after 9 days and comparable in two mouse strains, and (c) adherence of reovirus to and their endocytosis by absorptive cells of suckling mice is determined by the viral hemagglutinin (sigma 1 protein).

Bone marrow ablation followed by allogeneic marrow grafting during first complete remission of acute nonlymphocytic leukemia

Of 33 patients who had undergone allogeneic bone marrow transplantation during first complete remission of acute nonlymphocytic leukemia, 21 patients have now been followed in continued complete remission for 6-64 mo (median greater than 18 mo) without maintenance chemotherapy. The median age of the surviving patients is 27 yr. Transplant-related complications occurring throughout the first year after marrow grafting were fatal in 7 patients, and leukemic recurrence led to the death of 5 patients. The actuarial long-term disease-free survival is 60% and the actuarial remission rate is 79%.

The sigma 1 protein determines the extent of spread of reovirus from the gastrointestinal tract of mice

After intragastric inoculation of adult mice, type 1 reovirus was initially concentrated in Peyer's patches over the first 4 hr after inoculation, then spread sequentially to the mesenteric lymph nodes and spleen. For type 3 reovirus, however, initial entry into Peyer's patches in adult mice was followed by loss of viral infectivity so that by 4 hr after inoculation virtually no infectious virus was detected in the intestine, and spread to extraintestinal tissues did not occur. In 10-day-old mice, type 3 was capable of spread to the mesenteric lymph nodes but not the spleen. Thus, as animals aged there was a greater restriction of the spread of type 3 from the intestine. Studies using a field isolate of type 3 reovirus that is resistant to intestinal proteases, and genetic studies utilizing type 1 x type 3 viral reassortants, revealed that the viral sigma 1 protein determined the capacity of reovirus to spread from the intestine in both adult and 10-day-old mice. Thus, the interaction of reovirus with host defense mechanisms, and the age-dependent restriction of spread of type 3 reovirus from the intestine are mediated by the viral sigma 1 protein.

Successful second bone marrow transplantation in a patient with myositis ossificans progressiva and aplastic anemia

Bone marrow transplantation has become the treatment of choice for patients with severe aplastic anemia who are fortunate enough to have allogeneic sibling donors. As patients have been transplanted earlier in the course of their disease, significant improvements have been obtained in long-term survival. However, in patients who have been sensitized by previous blood product transfusions, graft rejection continues to be a significant problem and second transplants when performed are frequently unsuccessful. This case report deals with a patient with myositis ossificans progressiva (MOP) who developed severe idiopathic aplastic anemia. He rejected his first graft after 160 days. However, he was successfully reingrafted with marrow from the same donor using a different conditioning regimen.

Platelet transfusion therapy in an alloimmunized patient. The value of crossmatch procedures for donor selection

A 51-year-old patient with acute myelogenous leukemia, who was alloimmunized to platelets, failed to show adequate platelet increments after receiving transfusions of HLA grade A-identical platelets. Only platelets from an HLA grade B-matching donor gave high increments. Several crossmatching procedures were used to select platelet donors. A correlation was seen between in vitro tests and in vivo response. HLA typing has limitations in the selection of platelet-compatible donors.

Structural features of the rat small intestinal microvillus membrane in acute experimental diabetes

Experimentally induced diabetes enhances the specific activity of several microvillus membrane proteins in the rat small intestine. The increase in the specific activity of sucrase-isomaltase has been shown by others to be due to an increase in enzyme protein, raising the possibility that diabetes induces a generalized increase in microvillus membrane proteins. Since intramembrane particles (IMPs) seen on freeze-fracture replicas of microvillus membranes are thought to represent integral membrane proteins, we compared microvillus IMP densities in diabetic rats with those in control rats. In addition, mucosal sucrase, maltase, and alkaline phosphatase specific activities were measured in all animals. Diabetic rats had significantly increased sucrase and maltase but not alkaline phosphatase specific activities compared with control rats. The density of microvillus IMPs on both the protoplasmic and extracellular fracture faces of undifferentiated crypt cells and villus absorptive cells was not increased in experimental diabetes. These data indicate that diabetes does not result in a generalized increase in microvillus membrane proteins. Thus the enhanced activity of microvillus membrane proteins in diabetes appears to be highly selective.

Reversal of acute ("malignant") myelosclerosis by allogeneic bone marrow transplantation

A 28-yr-old woman with acute malignant myelosclerosis received, as primary treatment, ablative chemotherapy and total body radiation therapy followed by bone marrow transplantation from her histocompatible brother. The patient is now well more than 15 mo after bone marrow transplantation, with normal peripheral blood counts, a normal bone marrow, no evidence of graft-versus-host disease, and is on no therapy. In light of the poor results obtained with conventional chemotherapy in this disease, bone marrow transplantation may represent the treatment of choice for patients who have an appropriate donor.

Susceptibility of mice to rotavirus infection: effects of age and administration of corticosteroids

We examined susceptibility to the murine rotavirus, epizootic diarrhea of infant mice virus (EDIM), in normal suckling and weaned mice and in suckling mice treated with glucocorticoids. Normal mice 1 to 40 days old were inoculated by gastrin intubation with high doses of EDIM and subsequently evaluated for rotavirus infection by solid-phase radioimmunoassay, by electron microscopy of intestinal tissue sections or by both. Radioimmunoassay and electron microscopy showed a concordance of 89.5% in the detection of rotavirus infection. After a period of low susceptibility to EDIM infection during the first 3 days after birth (23%), susceptibility was high for the next 11 days (95%), but decreased abruptly as mice approached weaning (41% on days 15 through 17). Mice 34 days or older did not develop EDIM infection after inoculation, but rotavirus antigen was detected in 12% of uninoculated mothers nursing inoculated litters. Administration of cortisone acetate to 8-day-old mice induced partial intestinal maturation prematurely. At 3 to 6 days after cortisone acetate treatment, susceptibility to EDIM infection decreased to 60% compared with 94% in age-matched controls. Our data suggest (i) that susceptibility of mice to EDIM infection is age dependent, decreasing in concert with intestinal maturation, and (ii) that glucocorticoids, which induce premature partial intestinal maturation, modulate susceptibility of mice to EDIM.

Intestinal M cells: a pathway for entry of reovirus into the host

Thirty minutes after inoculation of reovirus type 1 into the intestinal lumen of the mouse, viruses were found adhering to the surface of intestinal M cells but not other epithelial cells. Within 1 hour, viruses were seen in the M cell cytoplasm and were associated with mononuclear cells in the intercellular space adjacent to the M cell. These findings suggest that M cells are the site where reovirus penetrates the intestinal epithelium.

Terminal deoxynucleotidyl transferase-positive lymphadenopathy in acute-phase chronic granulocytic leukemia

A patient who had Philadelphia chromosome-positive chronic granulocytic leukemia had generalized lymphadenopathy. The lymph node biopsy revealed blast cells with small numbers of eosinophilic myelocytes indicative of granulocytic differentiation. In addition, the blast cells were found to have Philadelphia (Ph1) chromosome and extremely high levels of terminal deoxynucleotidyl transferase (TdT). The patient's peripheral blood and bone marrow reverted to the chronic phase, and the lymphadenopathy disappeared on two occasions with vincristine and prednisone therapy. The extramedullary proliferation of blastic chronic granulocytic leukemia, therefore, seems to share the histologic, cytogenetic biochemical, and chemotherapeutic sensitivity features of the basic disease process. TdT assay of enlarged lymph nodes in acute-phase chronic granulocytic leukemia might be used to identify the patients responsive to vincristine and prednisone despite the granulocytic histologic features of their lymph nodes.

Combined idiopathic neutropenia and thrombocytopenia: evidence for an immune basis for the syndrome

We report a case of combined idiopathic immune neutropenia and immune thrombocytopenia (thromboneutropenia). Therapy with prednisone was ineffective. Treatment with vincristine raised the patient's platelet count but did not increase the neutrophil count. Splenectomy led to a prompt complete remission. Using radioimmunologic techniques, we have shown both antiplatelet and antineutrophil antibodies and have shown the disappearance of these antibodies after successful treatment.