G. W. Santos
Johns Hopkins University
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Featured researches published by G. W. Santos.
The Lancet | 1989
RichardJ. Jones; AllanD. Hess; RisaB. Mann; Steven Piantadosi; G. B. Vogelsang; EvanR. Farmer; RobertB. Geller; G. W. Santos
To induce graft-versus-host disease (GvHD) in patients undergoing autologous bone marrow transplantation (BMT), five consecutive patients with non-Hodgkin lymphoma or Hodgkins disease in resistant relapse were treated with cyclophosphamide and total body irradiation or busulphan and cyclophosphamide, followed by autologous BMT. The patients received cyclosporin 1 mg/kg per day intravenously for 28 days after BMT. Histologically proven grade II acute GvHD of the skin developed in all the patients at a median of 11 days (range 9-13) after BMT. One patient died and the GvHD resolved in 1-3 weeks in the four remaining patients--spontaneously in two and with corticosteroid treatment in two. Lymphocytes from one patient obtained at the time of GvHD were cytotoxic for the patients own pretransplant lymphocytes. Cytotoxicity was blocked by antibodies directed against class II histocompatibility (HLA-DR or Ia) antigens. Cyclosporin-induced GvHD after autologous BMT resembles mild GvHD after allogeneic grafting. This syndrome appears to be mediated by autoreactive Ia-specific lymphocytes.
Journal of Clinical Oncology | 1990
John R. Wingard; S Piantadosi; G. W. Santos; Rein Saral; Huibert M. Vriesendorp; Andrew M. Yeager; W. H. Burns; Richard F. Ambinder; Hayden G. Braine; Gerald J. Elfenbein
Seventy-four consecutive patients with high-risk acute lymphoblastic leukemia (ALL) were given cyclophosphamide (CY; 50 mg/kg on each of 4 days) plus total body irradiation (TBI; 300 rad on each of 4 days) followed by a human leukocyte antigen (HLA)-identical allogeneic bone marrow transplant (BMT). Eighteen patients in first complete remission (CR1), 36 in CR2, 16 in CR3, and four in CR4 were transplanted. Patients in CR1 were transplanted 1 to 8 months (median, 3 months) after attaining CR. All 18 patients in CR1 had one or more poor risk factors: age more than 18 (N = 17), initial leukocyte count greater than or equal to 20,000 (N = 11), Ph 1 chromosome (N = 2), delay in attaining CR more than 6 weeks (N = 8), or extramedullary disease (N = 1). Of those transplanted in CR2, 72% had relapsed on therapy. The 5-year event-free survival (EFS) rates for patients transplanted in CR1, CR2, and CR3 are 42%, 43%, and 25%, respectively, at median follow-up times of 57, 54, and 72 months, respectively. Children aged less than 18 years transplanted in CR2 have a 5-year EFS rate of 54%. All CR4 patients died early after transplant. The actuarial probability of relapse is 20%, 26%, and 48% for those transplanted in CR1, CR2, and CR3, respectively. Although there was substantial transplant-associated mortality, it decreased over the decade of the study (P = .01). This study indicates that BMT offers an attractive alternative to postremission chemotherapy in patients in CR1 with poor prognostic factors and in patients in second remission.
Transplantation | 1988
John R. Wingard; M. B. Sostrin; Huibert M. Vriesendorp; E. D. Mellits; G. W. Santos; Dj Fuller; Hayden G. Braine; Andrew M. Yeager; W. H. Burns; Rein Saral
Interstitial pneumonitis (IP) occurred in 20 of 143 14%) patients who received cytoreductive therapy followed by autologous bone marrow transplantation BMT) as treatment for malignancy. IP occurred at a median onset time of 41 days (5 to 624 days). All but three of the episodes were fatal. Of the thirteen cases in which tissue was examined, half were idiopathic; the remainder were due to various infectious agents. The lectuarial incidences of idiopathic (7%) and CMV IP (2%) these marrow autograft recipients were lower than he incidences of idiopathic (19%) and CMV IP (17%) in comparably treated recipients of allogeneic BMT p≤0.001 for both comparisons).
The Lancet | 1982
TimothyR. Townsend; Robert H. Yolken; CatherineA. Bishop; G. W. Santos; ElizabethA. Bolyard; WilliamE. Beschorner; W. H. Burns; Rein Saral
In a three-week period 7 of 14 transplant recipients were infected with coxsackie A1 virus. Diarrhoea and mortality were significantly associated with infection (7 of 7 infected compared with 0 of 7 non-infected, and 6 of 7 infected compared with 1 of 7 non-infected, respectively). Early in the outbreak, the diarrhoea was presumed to be due to acute graft-versus-host disease (AGVHD). However, the distribution of AGVHD among infected and non-infected patients was nearly equal, and at necropsy 3 of 6 infected patients who had had diarrhoea showed no evidence of gastrointestinal involvement with AGVHD. Infection with viral enteric pathogens may be an important factor in the clinical course of transplant recipients.
Transplantation | 1994
Wojno Kj; Georgia B. Vogelsang; William E. Beschorner; G. W. Santos
Acute graft-versus-host disease (GVHD) has recently been associated with endothelial cell injury. The potential clinical significance was explored here in an autopsy review. Thirty-seven allogeneic bone marrow recipients were identified in the autopsy files at The Johns Hopkins Hospital with no evidence of systemic infection. Forty-one percent (15/37) of these patients were found to have extensive recent pulmonary hemorrhage at autopsy which was thought to have led to terminal respiratory failure and death. The 37 patients were divided into 2 groups: those with significant acute GVHD (stage 2 or greater) and those without GVHD (stage 0 or 1). Fifty-nine percent (10/17) of the patients with significant acute GVHD died of acute respiratory failure due to recent pulmonary hemorrhage as opposed to 25% (5/20) of those without acute GVHD (P = 0.032, Fishers exact test). Terminal pulmonary hemorrhage was also associated with preparation for BMT, with 67% (12/18) of those prepared with total body irradiation (TBI) having pulmonary hemorrhage as opposed to 15% (3/19) of those prepared with chemotherapy using Busulphan (P = 0.002). There was no significant difference in posttransplant survival, engraftment, or final platelet count between the patients stratified by GVHD or preparative protocol. The data support a strong association between significant acute GVHD and terminal hemorrhage, as well a possible association between TBI and pulmonary hemorrhage. Analysis of variance demonstrates that GVHD and TBI are independently associated with increased pulmonary hemorrhage (P < 0.01 for GVHD, P < 0.001 for TBI). We propose that GVHD contributes to terminal pulmonary hemorrhage by injuring the endothelium. However, this association could also be a secondary effect, i.e., toxicity from therapy for GVHD, or an abnormality in cytokines or growth factors. The pathogenic relationship between significant GVHD and terminal hemorrhage is discussed briefly.
Journal of Cutaneous Pathology | 1985
S. R. Hymes; S. C. Simonton; Evan R. Farmer; W. B. Beschorner; Peter J. Tutschka; G. W. Santos
Epidermal keratinocytes with abnormally large nuclei were found in 12 of 13 patients who received high‐dose busulfan and cyclophosphamide prior to receiving bone‐marrow transplantation for treatment of hematological malignancies. These cells were similar to those previously described in the lungs, cervix and bladder of patients on long‐term busulfan therapy. Marked keratinoeyte nuclear abnormalities were not observed in bone‐marrow transplant recipients who received a preparatory regimen of cyclophosphumide and total‐body irradiation. This histologic cutaneous busulfan effect was transient and was unrelated to the development of graft ‐versus‐host reaction.
Journal of Clinical Oncology | 1988
Robert B. Geller; G. B. Vogelsang; John R. Wingard; Andrew M. Yeager; W. H. Burns; G. W. Santos; Rein Saral
Five patients with acute myelocytic leukemia (AML) after combined modality therapy for Hodgkins disease (HD) were treated with cyclophosphamide and busulfan followed by bone marrow transplantation (BMT). Four patients received allogeneic transplants from histocompatibility locus antigen (HLA)-compatible siblings and the fifth patient received an autologous marrow treated with 4-hydroperoxycyclophosphamide. Two patients died of complications of acute graft-v-host disease (GVHD) despite prophylaxis with either low-dose cyclophosphamide or cyclosporine. The remaining three patients were alive and disease-free 382, 617, and 620 days after transplant. These initial results are encouraging and more patients with treatment-related AML need to be evaluated with both allogeneic and autologous BMT to fully elucidate the potentially curative role of this intensive therapy in an otherwise fatal hematologic malignancy.
Transplantation | 1988
William E. Beschorner; Charlotte Shinn; Anne C. Fischer; G. W. Santos; Allan D. Hess
Cyclosporine‐induced pseudo‐graft‐versus‐host disease (CIPGVHD) in syngeneic or autologous rat marrow chimeras has clinical and histologic features closely resembling classic graft‐versus‐host disease in the allogeneic chimera. We describe here the pathology and immunopathology of the usual target tissues in CIPGVHD developing in the first week following CsA (early group). The findings are contrasted to the CIPGVHD developing during the second week post‐CsA (later group). Six of 9 rats in the early group had acute‐type CIPGVHD in the tongue, skin, liver, intestines, and mainstem bronchi. In general, the lymphocytic infiltrates in these tissues were in intimate contact with injured epithelial cells. The intestines had multiple apoptotic lesions. Class II antigen was prominent in the tongue mucosa, but only patchy expression was evident in 2 skin biopsies. All of the lymphocytes infiltrating the mucosa were CD8+(OX‐8)/CD4‐(W3/25) T cells (OX‐19+). Most of the lymphocytes in the lamina propria expressed CD4 as well as CD8 markers, suggesting coexpression. In the later group, 6 of 7 rats had chronic‐type CIPGVHD (1 with acute and chronic) while 1 rat had no GVHD (P=.02, Fishers exact test compared with the early group). These animals had features characteristic of established chronic GVHD in the skin, tongue, liver, intestines, and salivary glands. Fibrosis of the dermis and lamina propria was prominent in the skin and tongue. Submucosal fibrosis was increased in the small intestine. The salivary glands had an interstitial infiltrate and fibrosis with loss of ducts and glands. Class II antigen was prominent in the epidermis of the tongue and skin of all rats. The number of lymphocytes infiltrating the mucosa of the tongue was considerably smaller than seen in the early group. More than 90% of these cells were T cells, as detected by OX‐19, and expressed both CD4 and CD8 markers. While most lamina propria lymphocytes expressed the CD4 antigen, there were significantly fewer CD8+ cells, consistent with increased numbers of CD8‐/CD4+ helper‐phenotype cells. The observations indicate that immediately post‐CsA, the CIPGVHD is primarily acute, with epithelial infiltrates of CD8+/CD4‐ T cells and lamina propria infiltrates that include double‐labeled cells consistent with immature thymocytes. There is a rapid transition to established chronic‐type CIPGVHD by the second week. The residual mucosal infiltrate is now dominated by double‐labeled T cells or thymocytes while the lamina propria infiltrate has more mature helper‐phenotype T cells. Induced RT1.B/D antigen could be important in the pathogenesis of the peripheral tissue manifestations.
Transplantation | 1987
William E. Beschorner; Farmer Er; Rein Saral; Stirling Wl; G. W. Santos
Induced class II histocompatibility antigens have been observed in the target tissues of rodents and humans with acute graft-versus-host disease (GVHD). Possibly this expression triggers the target tissue phase, through antigen presentation, lymphocyte recruitment, or additional antigenic stimulus. We have tested whether the induced expression is required for cutaneous GVHD in human marrow recipients. Ninety-two skin biopsies from 37 allogeneic marrow recipients at the Johns Hopkins Bone Marrow Transplant Unit were stained for HLA-DR, OKT6 (Langerhans cells), and for surface markers of lymphocyte and monocytes. Of 22 biopsies taken at the onset of GVHD, 12 did not have detectable HLA-DR antigen, and 10 had patchy-to-diffuse expression. The biopsies with HLA-DR−GVHD consisted primarily of epithelial infiltrates of cytotoxic/suppressor cells (CD8+), while those with HLA-DR+ GVHD had a mixed infiltrate with more helper/inducer/class-II-re-active cells (CD4+) in the epidermis and dermis and more monocytes in the dermis. Eight of 9 patients with HLA-DR−GVHD had follow-up biopsies that later expressed epithelial DR antigen, but the epidermal and dermal infiltrates showed no significant changes. Most of those receiving cyclosporine (CsA) prophylaxis (7/9) developed HLA-DR−GVHD, while those receiving cyclophosphamide were split between the two groups (8 of 13 were HLA-DR+). HLA-DR antigen expression was evident in some biopsies with no GVHD or minimal GVHD but did not appear to predict the development of GVHD or the type of GVHD. HLA-DR antigen expression was not evident in 2 of 3 initial biopsies of lichenoid-type chronic GVHD. Class II antigen induction is clearly not necessary for the target phase in most patients of this study.
Archive | 1985
Hayden G. Braine; H. Kaizer; Andrew M. Yeager; Robert K. Stuart; W. H. Burns; Rein Saral; Lyle L. Sensenbrenner; G. W. Santos
The observation that syngeneic marrow transplantation following supralethal cytoreductive therapy can produce relatively long-term disease-free survival in a significant fraction of patients with acute leukemia [1] and non-Hodgkin’s lymphoma [2, 3] suggests that cure of these diseases may be achieved with marrow transplantation without the hazards of graft-versus-host disease that accompany allogeneic marrow transplants.