Graft-versus-host disease as adoptive immunotherapy in patients with advanced hematologic neoplasms

The occurrence of graft-versus-host disease (GVHD) after allogeneic bone marrow transplantation for leukemia is thought to decrease the probability of recurrence. To study this effect (called adoptive immunotherapy) we modified the prophylaxis of GVHD in patients with advanced hematologic neoplasms (mostly leukemia) who received bone marrow transplants. Patients under 30 years of age were randomly assigned to one of three regimens of post-transplantation immunosuppression: Group I (n = 44) received a standard course of methotrexate for 102 days after transplantation, Group II (n = 40) received an abbreviated (11-day) course of methotrexate, and Group III (n = 25) received the standard course of methotrexate plus viable buffy-coat cells from the marrow donors. All 109 patients received cyclophosphamide (60 mg per kilogram of body weight on each of two days), total-body irradiation (2.25 Gy daily for seven days), and unmodified marrow from HLA-identical sibling donors. The frequency of GVHD of Grades II through IV was 25 percent in Group I, 59 percent in Group II, and 82 percent in Group III (P = 0.0001). The incidence of chronic GVHD, however, did not differ significantly among the groups (33, 51, and 44 percent, respectively), nor did the five-year probability of recurrence of disease (38, 45, and 33 percent, respectively). However, mortality from causes other than cancer was 34 percent in Group I, 45 percent in Group II, and 64 percent in Group III (I vs. III, P = 0.024); the deaths were due primarily to infections complicating the course of GVHD. With a median follow-up of 5.1 years (range, 3.9 to 7.4), disease-free survival was 41 percent in Group I, 30 percent in Group II, and 24 percent in Group III (the differences were not statistically significant). We conclude that abbreviating methotrexate prophylaxis or infusing donor buffy-coat cells increased the incidence of acute GVHD and related mortality without altering the incidence of chronic GVHD or the recurrence of malignant disease.     

Medication adherence in patients with HIV infection: a comparison of two measurement methods

Two measurements of adherence, patient self-report and electronic measurement by the Medication Event Monitoring System (MEMS), were compared in a 3-month adherence study of 44 HIV-infected patients who had been placed on regimens that included protease inhibitors (PIs). The dose percentage and degree of clinically significant dosing time fluctuation were calculated monthly. The mean dose percentage by self-report versus MEMS was 97.5% versus 90.3% during month 1 of adherence monitoring, 96.5 versus 90.1% during month 2, and 98.4% versus 92.8% during month 3. Thirty-two percent of patients taking PIs and 21% of patients taking nucleoside analogues demonstrated clinically significant dosing time fluctuation. Our data confirm that self-reports of adherence overestimate true adherence behavior, and patients' self-reports of dosing times may not accurately reflect their deviation from those times.     

Transmission of human cytomegalovirus from infected uterine microvascular endothelial cells to differentiating/invasive placental cytotrophoblasts

Analysis of placentas infected with human cytomegalovirus (CMV) suggested that viral transmission could involve differentiating/invasive cytotrophoblasts in villi that attach the placenta to the uterine wall. To parse the cellular components in this process, we developed a coculture system of polarized uterine microvascular endothelial cell (UtMVEC) infection with an endothelial cell-tropic pathogenic strain of CMV. Then we evaluated the potential role of neutrophils and endothelial cells in the spread of infection to differentiating cytotrophoblasts. As shown by immunocytochemistry and analysis of viral replication, CMV preferentially infected endothelial cells via apical membranes and disrupted cell junction proteins, thereby altering paracellular permeability and cell polarity. Neutralizing antibodies to CMV glycoprotein B, an envelope component that facilitates virion penetration, blocked plaque formation in polarized UtMVEC. Neutrophils transmitted CMV infection to UtMVEC, which in turn infected cytotrophoblasts. However, neutrophils did not directly infect cytotrophoblasts. These findings implicate endothelial cells from the uterine microvasculature as a potential source for CMV infection of endovascular cytotrophoblasts of the anchoring villi. Possibly the cytokine/chemokine milieu in the pregnant uterus could attract immune cells that infect endothelial cells in hybrid fetal-maternal vessels. In turn, these cells could infect endovascular cytotrophoblasts, one possible initiation point of a cascade that results in retrograde placental CMV infection.     

Immunoprophylaxis of Chlamydia trachomatis lymphogranuloma venereum pneumonitis in mice by oral immunization.

Groups of BALB/c mice were orally immunized with chlamydiae and challenged intranasally to determine whether oral immunization offers protection against pulmonary disease and to characterize the nature and kinetics of the chlamydial antibody response in the lung and other mucosal sites. Protection by oral immunization from chlamydial lung disease was demonstrated by lack of replication of the organism and the lack of chlamydial antigen in lung tissue. The chlamydial immunoglobulin A (IgA) antibody response was present at all body sites, reaching peak levels in the lung as well as in the serum. Classical IgA booster effect kinetics was observed after intranasal challenge, especially in the lung. Specific IgG antibody was detected at all body sites but at lower levels. Furthermore, animals immunized orally had no pneumonic process, as determined by histopathology. These studies also suggest that passively acquired specific serum IgG antibody may not significantly influence the course of mucosal replication of the organism. These observations indicate that oral immunization activating the gut-associated lymphoid tissue system gave total protection against chlamydial lung disease, suggesting migration of immunologically competent cells from the intestine to the lung.     

Permeation of human ovarian tissue with cryoprotective agents in preparation for cryopreservation

The recent improvements in the treatment of cancer by chemo- and radiotherapy have led to a significant increase in the survival rates of patients with malignant disease, but at the expense of distressing side effects. One major problem, especially for younger patients, is that aggressive therapy destroys a significant proportion of the follicular population, which can result in either temporary or permanent infertility. Freeze-banking pieces of ovarian cortex prior to treatment is one strategy for preserving fecundity. When the patient is in remission, fertility could, theoretically, be restored by autografting the thawed tissue at the orthotopic site or by growing isolated follicles to maturity in vitro. Recent studies have found good follicular survival in frozen-thawed human ovarian tissue but to optimize the process an effective cryopreservation method needs to be developed. An essential part of such a technique is to permeate the tissue with a cryoprotectant to minimize ice formation and the extent of this equilibration is an important determinant of post-thaw cellular survival. In the current study, we have investigated the diffusion of four cryoprotective agents into human tissue at both 4 degrees C and 37 degrees C. We have also studied the effect of adding different concentrations of the non penetrating cryoprotective agent, sucrose, to the freezing media using the release of lactate dehydrogenase as a measure of its protective effect. At 4 degrees C propylene glycol and glycerol penetrated the tissue significantly slower than either ethylene glycol or dimethyl sulphoxide. At the higher temperature of 37 degrees C all four cryoprotectants penetrated at a faster rate, however concern about enhanced toxicity prevents the use of these conditions in practice. Thus, the results suggest that the best method of preparing tissue for freezing is exposure for 30 min to 1.5 M solutions of ethylene glycol or dimethyl sulphoxide at 4 degrees C; this achieved a mean tissue concentration that was almost 80% that of the bathing solution. We also report that the addition of low concentrations of sucrose to the freezing medium does not have a significant protective effect against freezing injury.      

Use of stereolithography to manufacture critical-sized 3D biodegradable scaffolds for bone ingrowth

A novel approach to the manufacture of biodegradable polymeric scaffolds for tissue-engineering utilizing stereolithography (SLA) is presented. SLA is a three-dimensional (3D) printing method that uses an ultraviolet laser to photo-crosslink a liquid polymer substrate. The current generation of SLA devices provide a 3D printing resolution of 0.1 mm. The experiments utilized a biodegradable resin mixture of diethyl fumarate (DEF), poly(propylene fumarate) (PPF), and a photoinitiator, bisacylphosphine oxide (BAPO). The PPF is crosslinked with the use of the SLA's UV laser (325-nm wavelength). An SLA device was retrofitted with a custom fixture build tank enclosing an elevator-driven build table. A 3D prototype model testing the manufacturing control this device provides was created in a computer-aided-design package. The resulting geometric data were used to drive the SLA process, and a DEF/PPF prototype part was successfully manufactured. These scaffolds have application in the tissue engineering of bony substrates.     

The role of the graft in the induction of tolerance by antilymphocyte serum and cellular antigen

Intravenous donor antigen in the form of spleen cells can significantly potentiate the effects of ALS in prolonging the survival of skin allografts exchanged across both weak and strong histocompatibility barriers. This effect depends on the proper timing of antigen administration and can result in immunologic unresponsiveness of sufficient strength to permit acceptance of second set grafts. The skin allograft itself apparently plays a role in the establishment of this unresponsive state since ALS and antigen alone followed by delayed allografts at 21 days resulted in normal graft rejection times.