The IFM 90 trial was designed to compare conventional chemotherapy (CC) and high-dose therapy (HDT). This trial demonstrated a significant superiority of HDT over CC regarding response rate, event-free-survival, and overall survival. Further improvements of HDT can be expected both in terms of feasibility (with the combined use of hematopoietic growth factors and peripheral blood stem cells) and in terms of response rate (using tandem transplants). A substantial improvement in long-term survival, however, will require the development of effective maintenance therapy to control the minimal residual disease present after transplant.

To evaluate the impact of granulocyte-macrophage colony-stimulating factor (GM-CSF) or placebo on the durations of intravenous (IV) antibiotic use, hospitalization, neutropenia, and fever, as well as remission rates, after high-dose melphalan (HDM) without stem-cell transplantation (SCT) in patients with multiple myeloma (MM).

To assess the clinical and economic benefit of low-dose (50 microg/m2) filgrastim after peripheral blood stem-cell transplantation (PBSCT) in a randomized, placebo-controlled double-blinded study.

Thirty patients diagnosed with breast cancer were included in a prospective randomized study comparing the in vivo priming effect of bioequivalent doses of glycosylated (lenograstim) and nonglycosylated (filgrastim) rG-CSF administration. Analysis of the efficacy of equivalent biological doses of both rG-CSFs showed no significant differences either in the mobilization of the subpopulations of PBPC considered (CD34+, CD34+/38-, CD34+/DR-), the content of such CD34+ cell subsets in the leukapheresis product, or the cost of the mobilization and collection procedures between both recombinant molecules. These results suggest that priming with bioequivalent doses of the two commercially available forms of glycosylated or nonglycosylated rG-CSF has a similar in vivo effect on PBPC mobilization.

G-CSF is routinely administered after autologous bone marrow or peripheral blood progenitor cell transplantation to enhance neutrophil engraftment. However, many different doses of G-CSF have been described with no clear consensus on the most cost-effective dose. We performed a prospective randomized trial examining the efficacy of three different doses of G-CSF post-autologous transplant (5, 10, or 16 micrograms/kg/day). Fifty-seven consecutive patients with breast cancer (n = 30), non-Hodgkin's lymphoma (n = 16), Hodgkin's disease (n = 6), multiple myeloma (n = 2), acute leukemia (n = 2), and testicular cancer (n = 1) were randomized, with 19 patients enrolled in each of the three treatment groups. All patients underwent a high-dose chemotherapy preparative regimen and received an autologous peripheral blood progenitor cell (PBPC) transplant (without bone marrow), with G-CSF beginning on day 0. There was no difference in time to neutrophil engraftment among the three treatment groups (mean 10.2 to 10.8 days). There is a trend towards earlier platelet engraftment in the patient group receiving 5 microgram/kg/day of G-CSF. The total cost of G-CSF by dose group was $2900, $4400, and $6500 per patient. We conclude that there was no advantage to the use of higher doses of G-CSF after autologous transplantation, and that lower doses are associated with lower costs.

In this placebo-controlled randomized trial we evaluated the hematological and clinical effects of r-Hu GM-CSF after high-dose chemotherapy (HDC) followed by GM-CSF-mobilized PBPC transplantation. Fifty patients with poor prognosis malignancies were randomized in a double-blind study to receive either GM-CSF or placebo after HDC followed by PBPC rescue. For all patients, PBPCs were recruited using a combination of VP-16 (300 mg/m2 on days 1 and 2), cytoxan (3 g/m2 on days 3 and 4) and GM-CSF (5 micrograms/kg from day 5). No differences were demonstrated between the two groups in median time to neutrophil or platelet recoveries. There was no significant difference between the GM-CSF group and the placebo group in the median duration of post-transplant hospitalization, in the number of days of antibiotic treatment, in the number of infections and in red blood cell or platelet transfusion requirements. There was a significant difference with an advantage for the placebo group in the mean duration of febrile days (P = 0.01). We conclude that the administration of GM-CSF in patients transplanted with GM-CSF-mobilized PBPC is not associated with a clinical benefit in term of tempo of engraftment, numbers of documented infections, transfusion requirements and mucositis grading.

A majority of patients with intermediate or high-grade non-Hodgkin's lymphoma (NHL) who are treated with high-dose chemotherapy (HDT) and hematopoietic stem cell transplantation subsequently relapse. Until recently, transplantation was associated with high morbidity and mortality and the focus was on improving the safety of this procedure. However, the use of growth factors and other supportive measures has successfully reduced treatment mortality to less than 5%. Therefore, new strategies need to be developed to eliminate the growth of any occult tumor cells reinfused with the stem cell products and the tumor cells remaining in the patient. One approach is to improve the immune function of the patients by a more rapid immune reconstitution and augmentation of effector cell function. We report studies comparing immune recovery following HDT and autologous peripheral stem cell transplantation (PSCT) as compared to autologous bone marrow transplantation (ABMT). These studies examined patients with intermediate and high-grade non-Hodgkin's lymphoma (NHL) who were treated with HDT and PSCT (n = 56) or ABMT (n = 60). The PSCT patients had a significantly faster recovery of circulating monocytes (CD14+ cells), natural killer ((NK) CD56+) cells, T helper (CD4+) cells, TCR gamma/delta cells, and naive T lymphocytes (CD45RA+). Following ABMT there was a significantly more rapid increase in the frequency of T suppressor/effector (CD8+) cells, B (CD19+) cells, CD34+ cells, polymorphonuclear leukocytes (PMN) and memory T lymphocytes (CD45RO+). The CD4:CD8 and CD45RA:CD45RO ratios were consistently higher in the PSCT group as compared to ABMT suggesting an improved ratio of T helper to T effector/suppressor cells and naive T cells. The differences in cellular phenotype translated into improved T cell function (PHA mitogenesis) and T cell help (pokeweed mitogenesis). In addition, there as an accelerated reconstitution of NK cell activity following PSCT as compared to ABMT. The more rapid reconstitution of NK and T cells in patients rescued with PSCT as compared to ABMT may contribute to an improved clinical outcome. Further, patients receiving a PSCT may be more responsive to adjuvant immunotherapy following transplantation.

In vitro and animal studies suggest that high concentrations of recombinant human erythropoietin (rHuEPO) might divert multipotent progenitors into erythroid maturation at the expense of granulocyte production. We determined whether changes of number and lineage commitment of peripheral blood progenitor cells occur in premature infants during therapy with rHuEPO. Thirty preterm infants were randomly assigned either to receive 300 IU of eopoetin alpha s.c. per kilogram body weight three times a week for four weeks or to a control group. At study entry and after two weeks of treatment the numbers of circulating BFU-E, granulocyte-macrophage colony-forming units (CFU-GM) and granulocyte-erythrocyte-macrophage-megakaryocyte CFU (CFU-GEMM) were analyzed by semisolid culture technique, CD34+ cells and early myeloid CD34+CD45RA- progenitors by flow cytometry. As compared with the control group, rHuEPO treatment did not exert any significant modulatory effect on numbers of CFU-GM, nor was there a significant change in numbers of BFU-E, CFU-GEMM, total-CFU, percentage of CD34+ or CD34+CD45RA- cells. Mean neutrophil count was not significantly reduced at any period during the study. Compared with the control group, the infants receiving rHuEPO had higher hematocrit values (p = 0.003) and absolute reticulocyte counts (p < 0.001). The median cumulative volume of blood transfused per kilogram per day was 0.86 ml (first quartile 0.5 ml; third quartile 1.1 ml) in the control group and 0 ml (first quartile 0 ml; third quartile 0.47 ml) in the rHuEPO group (p = 0.038). We conclude using a relatively high dose of rHuEPO in premature infants, no significant in vivo effect on circulating peripheral blood progenitor or neutrophil count could be detected.

Therapy for aggressive non-Hodgkin's lymphomas has undergone significant evolution in the past 25 years. First-generation combination chemotherapy studies produced complete response (CR) rates of 45-53% together with 30-37% rates of long-term survival. New treatment programs aimed at increasing CR rates were then developed on the assumption that the additional patients who achieved a CR would become long-term disease-free survivors. Initial reports of single-institution pilot studies with third-generation regimens suggested CR and survival rates of 68-86% and 58-69%, respectively; however, after longer follow-up-periods, survival rates decreased. Furthermore, confirmatory national phase II trials using these newer regimens produced CR rates of only 49-65% and survival rates of 50-61%. Thus, ultimate conclusions concerning the efficacy of these new regimens awaited the results of prospective randomized trials. The Southwest Oncology Group (SWOG) conducted a randomized trial comparing standard therapy. CHOP, to the third-generation chemotherapy regimens m-BACOD, ProMACE-CytaBOM, and MACOP-B. After 6 years, on difference in the response rate, progression-free survival, or overall survival has been found between CHOP and third-generation regimens. For example, the 6-year estimates of progression-free survival are CHOP 33%, m-BACOD 36%, ProMACE-CytaBOM 34%, and MACOP-B 32% (P = 0.41). The 6-year overall survival estimates are CHOP 42%, m-BACOD 40%, ProMACE-CytaBOM 46%, and MACOP-B 41% (P = 0.89). Furthermore, we have not identified any subset of patients who survive longer on treatment with the third-generation regimens, and the cost and toxicity of the new regimens are higher. On the basis that < 50% of these patients are cured, the best approach for any patient is an experimental one designed to improve our ability to cure the disease. Examples of this include (1) increasing the dose intensity of drugs used in standard regimens and (2) autologous bone marrow transplantation and/or peripheral stem-cell support as rescue from marrow-ablative chemotherapy. If a patient is not eligible or does not wish to participate in a clinical trial, CHOP, as inadequate as it is, remains the gold standard.

The clinical application of gene transfer is hindered by the availability of the multipotential stem cells and the difficulty in obtaining efficient retroviral transduction. To assess potential means by which gene transfer into human hemopoietic stem cells might be enhanced, the retroviral transduction efficiency of human bone marrow cells (BM) or peripheral blood progenitor cells (PBPC) was compared at multiple time points after in vivo administration of granulocyte colony-stimulating factor (G-CSF). This was further compared with the transduction efficiency of cells mobilized with G-CSF plus stem cell factor (SCF) in a cohort of patients randomized to receive either one or two growth factors and with normal BM function. Using the LNL6 retrovirus, retroviral transduction efficiencies of up to 19% were observed for both PBPC and BM (n = 26 patients). There was at least a 100-fold increase in PBPC with G-CSF alone and a further 30-fold increase in the total number of progenitor cells available for retroviral transduction using the combination of SCF plus G-CSF. However, pretreatment of patients with G-CSF with or without SCF did not enhance the retroviral infectability of growth factor-mobilized progenitor cells. The effect of the growth factor, Flk-2/Flt3 ligand (FL), was also examined with respect to retroviral transduction efficiency of human progenitor cells. FL plus IL-3 in vitro increased the retroviral transduction efficiency up to eightfold compared with results observed using other combinations of cytokines tested (P < .001). These findings have clinical implications both for increasing the number of target cells for in vivo gene-marking/gene-therapy studies and improving the efficiency of gene transfer.

It has been reported that hypophysectomized rats exhibit normochromic, normocytic anaemia. Pancytopenia with impaired DNA synthesis in the bone marrow can be restored in these hypophysectomized rats by syngeneic pituitary grafts placed under the kidney capsule or treatment with growth hormone (GH). Until now, adults with hypopituitarism have received adequate replacement therapy with thyroxine, cortisol and sex steroids, but not with GH. We therefore investigated the effects of GH replacement therapy on the proliferation and differentiation of erythroid and myeloid progenitor and peripheral blood cells in 11 adult patients with growth hormone deficiency in a double-blind, placebo-controlled study for the first 6 months of therapy. The placebo group showed no changes during the first 6 months without therapy in either insulin-like growth factor I (IGF-I) levels, erythroid and myeloid progenitor precursor cells or peripheral blood cells. After commencement of GH therapy, IGF-I levels rose significantly during 24 months of therapy from 75.3 +/- 13.5 to 225 +/- 34.7 ng mL-1 (P < 0.001). Erythroid and myeloid progenitor precursor cells showed a steep and significant increase after 18 and 24 months of therapy (erythroid: from 10.7 +/- 3.5 to 261.4 +/- 79.8, P < 0.02, after 18 months and to 276.8 +/- 149.8 x 10(5) mononuclear cell colonies, P < 0.03, after 24 months; granulocyte-macrophage colony-forming units: from 39.7 +/- 9.8 to 316.9 +/- 124.6, P < 0.002, after 18 months and to 366 +/- 188.7 x 10(5) mononuclear cell colonies, P < 0.03, after 24 months), whereas the peripheral red and white blood cells exhibited only minimal non-significant changes. The principal regulators of erythropoiesis, such as erythropoietin, and parameters reflecting erythropoiesis in the peripheral blood, such as reticulocytes, remained almost unchanged throughout the whole study period. We therefore conclude that patients with GH deficiency do not have anaemia, but have haematopoietic precursor cells in the lower normal range, and that GH substitution therapy over a period of 24 months has a marked effect on erythroid and myeloid progenitor precursor cells but only negligible effects on peripheral blood cells in GH-deficient adults.

Patients with non-myeloid hematologic malignancies (including Hodgkin's and non-Hodgkin's lymphomas, myeloma and acute lymphoid leukemia) or solid tumors underwent cytoreductive conditioning regimens followed by either autologous bone marrow transplantation (ABMT) (n = 343) or transplantation of peripheral blood stem cells (PBSC) with (n = 44) or without bone marrow (BM) (n = 16). In a randomized double-blind phase III multi-center trial, patients received either granulocyte-macrophage colony-stimulating factor (GM-CSF, 10 micrograms/kg/day) or placebo by daily i.v. infusion beginning 24 h after bone marrow infusion and continuing until the absolute neutrophil count (ANC) had recovered to > or = 1000/mm3, or for a maximum of 30 days. Median time to neutrophil recovery was significantly shorter in the GM-CSF group (18 vs 27 days, P < 0.001), and more GM-CSF patients had neutrophil recovery by day 30 (70 vs 48%). Median duration of hospitalization was significantly shorter in the GM-CSF group (29 vs 32 days, P = 0.02). GM-CSF significantly reduced the median time to neutrophil recovery in patients receiving bone marrow only (19 vs 27 days, P < 0.001) or PBSC with or without bone marrow (14 vs 21 days, P < 0.001). The overall incidence of adverse events was comparable in the two groups, although more patients in the GM-CSF group discontinued treatment due to adverse events (17 vs 9%, P < 0.001). No difference was noted in infection incidence or time to platelet independence. GM-CSF had no negative impact on time to relapse or long-term survival. These data indicate the positive influence of GM-CSF on neutrophil recovery and hospital stay in patients receiving ABMT for a variety of clinical indications.

We examined the prognostic impact of CD2 antigen expression for 651 patients with T-lineage acute lymphoblastic leukemia (ALL), who were enrolled in front-line Childrens Cancer Group treatment studies between 1983 and 1994. There was a statistically significant correlation between the CD2 antigen positive leukemic cell content of bone marrow and probability of remaining in bone marrow remission, as well as overall event-free survival (EFS) (P = .0003 and P = .002, log-rank tests for linear trend). When compared with patients with the highest CD2 expression level (> 75% positivity), the life table relative event rate (RER) was 1.22 for patients with intermediate range CD2 expression level (30% to 75% positivity) and 1.81 for "CD2-negative" patients (< 30% positivity). At 6 years postdiagnosis, the EFS estimates for the three CD2 expression groups (low positivity to high positivity) were 52.8%, 65.5%, and 71.9%, respectively. CD2 expression remained a significant predictor of EFS after adjustment for the effects of other covariates by multivariate regression, with a RER of 1.47 for CD2-negative patients (P = .04). Analysis of T-lineage ALL patients shows a significant separation in EFS after adjustment for the National Cancer Institute (NCI) age and white blood cell (WBC) criteria for standard and high-risk ALL (P = .002, RER = 1.67). The determination of CD2 expression on leukemic cells helped identify patients with the better and poorer prognoses in both of these risk group subsets. For standard risk T-lineage ALL, CD2-negative patients had a worse outcome (P = .0007, RER = 2.92) with an estimated 5-year EFS of 55.9% as compared with 78.3% for the CD2-positive patients. Thus, CD2 negativity in standard risk T-lineage ALL identified a group of patients who had a worse outcome than high-risk T-lineage ALL patients who were CD2 positive. The percentage of CD2 antigen positive leukemic cells from T-lineage ALL patients is a powerful predictor of EFS after chemotherapy. This prognostic relationship is the first instance in which a biological marker in T-lineage ALL has been unequivocally linked to treatment outcome.

Long-term culture-initiating cells (LTC-IC) are arguably the most primitive human hematopoietic cells detectable by in vitro functional assays. We have investigated the mobilization of these cells into the blood of patients with ovarian carcinoma randomized to receive granulocyte colony-stimulating factor (G-CSF; 5 micrograms/kg) plus different doses of stem cell factor (SCF; c-kit ligand) after chemotherapy or G-CSF alone after chemotherapy. We have shown a significant SCF dose response for the mobilization of LTC-IC, with a 5.8-fold increase in LTC-IC mobilization in those patients receiving chemotherapy, G-CSF, and 20 micrograms/kg of SCF, the highest dose used, compared with the patients receiving chemotherapy and G-CSF alone. We have shown a threefold increase in CD34+ cells and up to a 64-fold increase in CD34+/33- cells was seen in patients treated with chemotherapy, G-CSF, and 20 micrograms/kg of SCF compared with those patients treated with chemotherapy and G-CSF alone. However, significant numbers of CD34+/38- cells were only found in the patients receiving 20 micrograms/kg of SCF as part of their mobilization regimen. Patients receiving chemotherapy plus G-CSF and SCF have enhanced mobilization of primitive cells and of the more committed progenitor cells compared with those patients receiving chemotherapy followed by G-CSF alone.

Originally developed against the effects of ionizing radiations, amifostine is an organic thiophosphate compound shown able to selectively protect normal tissues against cytotoxic agents in cellular and animal models, without protecting tumor tissues. Amifostine is a prodrug which is dephosphorylated into its active metabolite, a free thiol derivative, by membrane alkaline phosphatase of the target issue. This unique metabolism supports its cellular selectivity and its preferential uptake by normal tissues. In phase II clinical trials, a decreased toxicity has been demonstrated in patients given alkylating agents; however, reduction of the response has not been observed. On the basis of these results, a prospective, randomized, phase III study has been conducted in patients with ovarian carcinoma receiving a combination of cisplatinum and cyclophosphamide. A significant decrease in hematologic, renal and neurologic toxicity was observed in the amifostine-treated patients compared with the control group, and response rates did not significantly differ between the two groups. Insufficient or emerging data are only available for other applications, including either in vitro manipulation of hematopoietic grafts or in vivo treatment of non-Hodgkin's lymphoma, head and neck carcinoma, non-small cell lung cancer and radioprotection. No data are yet available in regard to the potential protective effects of amifostine against mutagenicity and cancerogenicity of both chemo- and radiotherapy.

One of the main obstacles for the use of high-dose chemotherapy with autologous hematopoietic progenitor cell support in the treatment of malignancies is the possibility of reinfusing clonogenic tumor cells with the hematopoietic graft. Purging of the graft with chemicals can reduce the number of tumor cells but can also damage the normal hematopoietic progenitors. Preclinical studies showed that the phosphorylated sulfhydryl compound amifostine (WR-2721) can protect normal hematopoietic progenitors from damage from alkylating agents. We conducted a randomized clinical trial in patients with breast cancer, non-Hodgkin's lymphoma, and Hodgkin's disease undergoing autologous bone marrow transplant. In this study, patients were randomized to have their bone marrow purged with 4-hydroperoxycyclophosphamide (4-HC) with (arm A) or without (arm B) amifostine. The percentage of colony-forming unit granulocyte-macrophages recovered after purging was higher in the amifostine arm, both in patients with breast cancer and in those with lymphoma, although this difference was not statistically significant. In addition, the time to engraftment was significantly shorter in the amifostine arm in both cohorts. We showed that pretreatment of bone marrow with amifostine prior to purging with 4-HC can protect normal hematopoietic progenitors from damage by 4-HC. This resulted in shorter engraftment rates and less need for supportive care.

Consecutive patients with non-Hodgkin's lymphoma (NHL, n = 133) or Hodgkin's disease (HD, n = 20) were treated with 12.0 Gy of fractionated total body irradiation, etoposide 60 mg/kg, and CY 100 mg/kg followed by infusion of autologous hematopoietic stem cells. Seventy-nine patients received purged (n = 62) or unpurged BM (n = 17), and 74 received unpurged PBSCs alone (n = 56) or with BM (n = 18). The median day for achieving a sustained granulocyte count of 0.5 x 10(9)/I was 14 range (7-66) for BM recipients and 10 (7-30) for PBSC +/- BM recipients (P = 0.03). A platelet count of 20 x 10(9)/I was achieved at a median of day 24 (6-145) in BM recipients and day 11 (range, 7-56) in PBSC +/- BM recipients (P = 0.007). The median number of platelet units transfused was 86 (0-1432) for BM recipients and 30 (6-786) for PBSC +/- BM recipients (P = 0.001). The median number of hospital days was 36 (10-88) for BM recipients and 27 (14-76) for PBSC +/- BM recipients (P = 0.0001). The unadjusted Kaplan-Meier (KM) estimates of survival, event-free survival (EFS) and relapse at 2 years were 0.57, 0.45 and 0.43 for patients receiving BM and 0.55, 0.36 and 0.59 for patients receiving PBSC +/- BM. After adjusting for confounding variables, the estimated relative risk (RR) of death from any cause was 0.92 (P = 0.75), of relapse was 1.25 (P = 0.39), of non-relapse mortality was 0.71 (P = 0.42) and of mortality and/or relapse was 1.17 (P = 0.48) for patients receiving PBSC +/- BM as compared to BM. For 46 patients with NHL receiving unpurged PBSC alone, the unadjusted KM estimate of relapse was 0.61 compared with 0.48 for 52 comparable patients receiving purged BM, while the RR for relapse for patients receiving unpurged PBSCs was 1.37 (P = 0.33) after adjusting for other significant covariates. These data confirm previous observations that patients who receive PBSC +/- BM have faster engraftment, fewer transfusions and shorter hospital stays than patients who receive only BM. There were no statistically significant differences between the two groups in survival, relapse, death from causes other than relapse and event-free survival.

Fifteen consecutive patients with multiple myeloma (MM) scheduled for peripheral blood progenitor cell (PBPC) transplantation, were randomly selected to receive cyclophosphamide (CY) (4 g/m2) alone (group I) or associated with recombinant human granulocyte-macrophage colony stimulating factor (rhGM-CSF) (5 micrograms/kg/day) (group II). The mean time of neutropenia after CY administration was 9.8 +/- 4.3 days in group I and 6.4 +/- 1.2 days in group II (P = 0.0228). One hundred and eight aphereses were performed (7.1 +/- 1.8 aphereses per patient in group I and 6.4 +/- 2.8 aphereses per patient in group II). rhGM-CSF administration after CY allowed a higher collection of CD34+ cells in apheresis products (1.42 +/- 1.68 x 10(6) CD34+ cells/kg) in comparison to without factor administration (0.47 +/- 0.52 x 10(6) CD34+ cells/kg) (P = 0.0165). The mean number of cells infused per patient was 6.56 +/- 4.02 x 10(8) MNC/kg and 7.64 +/- 3.00 x 10(4) CFU-GM/kg in group I and 6.25 +/- 4.03 x 10(8) MNC/kg and 8.16 +/- 9.73 x 10(4) CFU-GM/kg in group II. The mean time to recover 0.5 x 10(9) granulocytes/I, 20 and 50 x 10(9) platelets/I in peripheral blood (PB) was 17.2 +/- 7.4, 13.4 +/- 3.7 and 16.5 +/- 6.9 days respectively, in group I and 13.3 +/- 1.7, 11.6 +/- 1.6 and 15 +/- 6.3 days, in group II. rhGM-CSF administration after CY treatment for PBPC mobilization in MM patients reduces the neutropenic period after CY and enhances apheresis CD34+ cell collection.

Retarded development and blastomere fragmentation of human preimplantation embryos represent a common phenomenon in in-vitro culture systems. Even though media composition is generally formulated to meet embryo nutritional requirements, the influence of antibiotic supplementation has not been investigated thoroughly. The present study was performed to evaluate the effects of antibiotics on embryo morphology and growth in modified culture media. A total of 196 zygotes from 18 couples was cultured in three different media: (i) conventional medium (n = 99, control group); (ii) medium modified with half the standard antibiotic concentration (n = 54; and (iii) antibiotic-free medium (n = 43); 49 embryos from the control group were selected at the zygote stage and transferred to the patients on day 2. The remaining 147 zygotes were cultured to the blastocyst stage for cryopreservation; their morphology and cell number were assessed daily at 40, 64, 88 and 112 h post-insemination. Overall cleavage rate was 95% and embryo scoring revealed 91% grade 1 embryos throughout the culture period in the three media. Significantly higher cleavage rates were obtained in the antibiotic-free medium at each observation, including the blastocyst stage, when compared to the other two groups. In addition, no notable improvement was observed in the embryos cultured in a reduced concentration of antibiotics. In conclusion, antibiotic supplementation of media has an adverse effect on the growth rate of preimplantation embryos, even in reduced concentrations, suggesting that antimicrobial drugs may interfere with the timing of cleavage events either by delaying or blocking embryo development.

The aim of this study was to examine the influence of endometrial cells on the fertilization rate and early embryonic morphology following routine in vitro fertilization (IVF). Cryopreservation with subsequent thawing allowed the use of autologous somatic cells, thus minimizing the risk of transmission of infective agents. Interpatient variability was eliminated by randomizing oocytes from each cycle into the control or coculture group.