Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Recombination”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 685 records · Page 38Linked to original sources
PubMed1992

In vivo synergism of recombinant human interleukin-3 and recombinant human interleukin-6 on thrombopoiesis in primates.

Using a primate model, we examined the effect of recombinant human interleukin-3 (rhIL-3) and rhIL-6 on thrombopoiesis in vivo. Administration of 33 micrograms/kg/d of rhIL-3 for 11 to 14 days increased levels of circulating colony-forming units megakaryocyte (CFU-Mk) by approximately 15-fold in five rhesus monkeys without raising their platelet counts. In contrast, administration of 30 micrograms/kg/d of rhIL-6 for 10 days in four animals did not increase CFU-Mk levels but significantly raised platelet counts from a mean pretreatment value of 460 x 10(3)/microL (range 360 to 610) to a mean maximum of 746 x 10(3)/microL (665 to 790) on day 8. If monkeys were pretreated with rhIL-3 (33 or 100 micrograms/kg/d for 11 days) to expand their CFU-Mk compartment, the thrombopoietic effect of rhIL-6 was synergistically enhanced leading to platelet counts above 1,000 x 10(3)/microL (mean maximum value 1,247) in all three primates studied. The sequential administration of rhIL-3 and rhIL-6 might represent a powerful strategy to stimulate thrombopoiesis in vivo.

Animals↗
PubMed1990

Phase I trial of continuous infusion recombinant interleukin-2 and intermittent recombinant interferon-alpha 2a: clinical effects.

A phase I trial of high-dose continuous infusion rIL-2 over 5 days and i.m. recombinant human interferon-alpha (rHuIFN-alpha 2a) three times weekly in 23 patients with advanced malignancy has been completed. Cohorts of patients were treated at three different dose levels: rIL-2 3.0 x 10(6) u/m2 plus rHuIFN-alpha 2a either 5.0 or 10.0 x 10(6) u/m2, and rIL-2 4.5 x 10(6) u/m2 plus rHuIFN-alpha 2a 5.0 x 10(6) u/m2 over 4 weeks. Dose-limiting toxicity consisted of pulmonary and neurologic side effects, and the maximal tolerated dose was 3.0 x 10(6) u/m2 on days 1-5 or rIL-2, and 10.0 x 10(6) u/m2 three times weekly of rHuIFN-alpha 2a. Four partial responses (renal carcinoma, three; endometrial carcinoma, one) were seen. In conclusion, toxicity of this schedule of rIL-2 and rHuIFN-alpha 2a was significant, but manageable. Further investigation is needed to define the antitumor activity of this combination.

Adult↗
PubMed1988

Recombinant gibbon interleukin-3 acts synergistically with recombinant human G-CSF and GM-CSF in vitro.

Recombinant gibbon interleukin-3 (IL-3) is a multilineage hematopoietic colony-stimulating factor (CSF) that recently was cloned and found to be highly homologous with human IL-3. Gibbon IL-3, as well as human granulocyte-CSF (G-CSF) and human granulocyte-macrophage CSF (GM-CSF), stimulated normal human bone marrow cells to form myeloid colonies in soft agar in a sigmoidal dose-response manner. When IL-3 was added to increasing concentrations of G-CSF or GM-CSF, synergistic colony formation occurred as compared with the effects of each CSF alone. Synergism was also noted when G-CSF was added with GM-CSF and when all the CSFs were added simultaneously. The combination of IL-3 and GM-CSF was less stimulatory than all the other CSF combinations. At day 11 of culture, IL-3 induced granulocyte-macrophage (38%), eosinophil (30%), granulocyte (18%), and macrophage (14%) colony formation. In summary, gibbon IL-3 is a growth factor that can synergize with other CSFs to enhance proliferation of myeloid-committed progenitors, suggesting that combinations of CSFs may have clinical utility in patients with neutropenia of various etiologies.

Animals↗
PubMed1989

Distinct antitumor mechanisms of recombinant interleukin-2 on recombinant interleukin-2-activated killer-sensitive and -resistant murine tumors.

The antitumor mechanism of recombinant human interleukin-2 (rIL-2) was studied using two murine tumor systems. Meth 8 tumor cells were easily lysed in vitro by rIL-2-activated killer (AK) cells, which mainly consisted of Thy1.2+, Lyt2.2+, L3T4- T cells, and asialo GM1+ natural killer (NK) cells; on the other hand, X5563 tumor cells were only slightly lysed in vitro by AK cells under the same conditions. One of these two tumors was inoculated i.d. into C3H/HeN mice and then rIL-2 (5 X 10(4) J.U./mouse/day) was repeatedly injected s.c. For AK-sensitive Meth 8-bearing mice, rIL-2 therapy starting 1 day after tumor inoculation was more effective for the growth than the therapy starting 7 days later and the therapeutic effect was abrogated by in vivo treatment with anti-asialo-GM1 serum. In contrast, for mice bearing AK-resistant X5563 tumor cells, delayed administration starting on day 7 or later was more beneficial than earlier administration on day 1 or 4. This treatment schedule resulted in complete tumor regression in a dose-dependent manner including significant inhibition of metastases in the spleen and/or lymph nodes. These therapeutic effects of rIL-2 on X5563 were not seen in T-depleted mice with anti-mouse thymocyte serum but were found in NK-depleted mice upon treatment with anti-asialo-GM1 serum. The results of these studies showed that the growth of AK-sensitive Meth 8 tumor was inhibited by AK cells, while the growth and metastases of AK-resistant X5563 tumor was inhibited by tumor-specific T cells, which were generated after tumor development and activated by rIL-2 therapy, rather than AK cells.

Animals↗
PubMed1989

Humoral response to recombinant interferon-alpha 2b in patients receiving recombinant interferon-alpha 2b therapy.

Twenty-seven patients in the chronic phase of a Philadelphia chromosome-positive chronic myelogenic leukemia (CML) underwent a monotherapy with recombinant interferon-alpha 2b (rIFN-alpha 2b), receiving a mean dose of 3 x 5 Mio. IU per week. Eight of the 27 patients developed both rIFN-alpha 2b-binding and -neutralizing antibodies during therapy. Sera of these patients abrogated both antiviral and antiproliferative activities of rIFN-alpha 2b, but not of nIFN-beta or rIFN gamma. Only one serum neutralized nIFN-alpha. The IFN binding and neutralizing titers rose during therapy, while a decrease occurred over months after cessation of therapy. The IgG fraction obtained by DEAE chromatography contained more than 90% of the IFN-neutralizing capacity of the purified sera. This result strongly suggested that IgG antibodies are responsible for the IFN-alpha-neutralizing activity.

Antibodies↗
PubMed1987

Synergistic antiproliferative effect of recombinant alpha-interferons with recombinant gamma-interferon.

Two human tumor cell lines were studied for their response to the antiproliferative effect of recombinant human interferons (IFNs) alpha 2, alpha 4, a hybrid alpha (delta 4 alpha 2 Bgl II alpha 1), and gamma, individually and in combination. Natural human alpha-IFN was used as a reference point for all experiments. RT4 (bladder carcinoma) cells were overall more sensitive to the antiproliferative effects of the IFNs than A2182 (lung adenocarcinoma) cells. Three-way analysis of variance indicated that the relative effectiveness of the alpha-IFNs was alpha 2 less than alpha 4 less than hybrid alpha less than natural alpha-IFN. On an international reference unit per milliliter basis, gamma-IFN was 50- and 75-fold more effective than natural alpha-IFN and hybrid alpha-IFN in RT4 cells and 5.6-, 12.1-, and 14.9-fold more effective than alpha 4-, hybrid alpha-, and natural alpha-IFN in A2182 cells. In contrast, when recalculated on a nanogram per milliliter basis, gamma-IFN was only threefold more effective than the hybrid alpha-IFN in RT4 and approximately twofold less effective than alpha 4 and the hybrid alpha in A2182. Combinations of alpha-IFNs gave additive or antagonistic effects. When any of the alpha-IFNs were combined with the gamma-IFN, however, a synergistic antiproliferative effect was seen. The magnitude of the synergy was dependent upon the concentration of gamma-IFN used and the type of alpha-IFN in the combination. Antagonistic effects were seen at the lowest gamma-IFN concentration studied (0.2 IRU/ml). Synergy also varied according to the potency of the alpha-IFN used.

Carcinoma↗
PubMed1988

[Comparative randomized study of the effectiveness of intravenous recombinant tissue-type plasminogen activator and intravenous streptokinase in patients with acute myocardial infarct. Report of the European Cooperative Study Group for Recombinant Tissue-Type Plasminogen Activator].

In a single-blind randomised trial in patients with acute myocardial infarction of less than 6 h duration, the frequency of coronary patency was found to be higher after intravenous administration of recombinant human tissue-type plasminogen activator (rt-PA) than after intravenous streptokinase. 64 patients were allocated to 0.75 mg rt-PA/kg over 90 min, and the infarct-related coronary artery was patent in 70% of 61 assessable coronary angiograms taken 75-90 min after the start of infusion; 65 patients were allocated to 1,500,000 IU streptokinase over 60 min, and the infarct-related vessel was patent in 55% of 62 assessable angiograms. The 95% confidence interval of the difference ranges from +30 to -2% (p = 0.054). Bleeding episodes and other complications were less common in the rt-PA patients than in the streptokinase group. Hospital mortality was identical in the 2 treatment groups. At the end of the rt-PA infusion the circulating fibrinogen level was 61 +/- 35% of the starting value, as measured by a coagulation-rate assay, and 69 +/- 25% as measured by sodium sulphite precipitation. After streptokinase infusion, corresponding fibrinogen levels were 12 +/- 18% and 20 +/- 11%. In the rt-PA group only 4.5% of the fibrinogen was measured as incoagulable fibrinogen degradation products, compared with 30% in the streptokinase group. Activation of the systemic fibrinolytic system was far less pronounced with rt-PA than with streptokinase.

Adult↗
PubMed1988

Synergistic antiproliferative effect of recombinant interferon-gamma with recombinant interferon-alpha on chronic myelogenous leukemia hematopoietic progenitor cells (CFU-GEMM, CFU-Mk, BFU-E, and CFU-GM).

Recombinant interferons, alpha (rIFN-alpha) and gamma (rIFN-gamma), have been demonstrated to have significant antitumor activity as single agents in the treatment of chronic myelogenous leukemia (CML). Due to their possible synergistic efficacy, a combination rIFN therapy in CML has been proposed. To establish a biologic basis for this, we have studied the suppressive effects of rIFN-alpha and rIFN-gamma on the in vitro growth of CML-derived progenitor cells (CFU-GEMM, CFU-Mk, BFU-E, CFU-GM), the optimal conditions for rIFN synergism, and the possible role of hematopoietic accessory cells (T-lymphocytes and monocytes-macrophages) in mediating rIFN-induced growth inhibition. When added to unseparated bone marrow cells, rIFN-alpha and rIFN-gamma significantly reduced colony formation, with 50% inhibition occurring at 71 and 186 U/mL for CFU-GEMM, 40 and 152 U/mL for CFU-Mk, 222 and 1,458 U/mL for BFU-E, and 119 and 442 U/mL for CFU-GM, respectively. A small amount of rIFN-gamma (5 U/mL) acted synergistically with increasing doses of rIFN-alpha, and the values of 50% inhibitory concentrations fell outside the lower limit (10 U/mL) used in our experiments. This synergy was evident even when rIFN-gamma was added 72 hours after the initiation of cultures; however, it was completely lost when the target cells were depleted of accessory cells. When a low dose of rIFN-alpha (5 U/mL) was added to rIFN-gamma, the 50% inhibitory concentration values were decreased up to tenfold. These studies (1) confirm that CML-derived hematopoietic progenitors are responsive to the suppressive activity of both rIFN-alpha and rIFN-gamma in vitro, (2) demonstrate that different mechanisms are responsible for the suppressive activity of the two rIFNs, and (3) characterize their synergistic interaction, providing a basis for future clinical trials aimed at investigating combination rIFN therapy in CML.

Bone Marrow↗
PubMed1977

[Formation of recombinants of F' plasmids in recombination-defective E. coli cells and their properties].

As a result of mating of cells carrying plasmid F' lac with cells carrying plasmid F'his merodiploids carrying plasmid complex F'lacF'his were isolated. The plasmid genes of the isolated merodiploids are donated together into the recipient cells and are eliminated jointly from host-cells both spontaneously and by acridine orange. As the formation of the plasmid complex took place in E. coli cells carrying mutation in rec A gene the recombination of plasmids F' is supposed to take place in the absence of the product of gene rec. A.

Escherichia coli↗
PubMed1994

The effect of recombinant human interleukin-3 and recombinant human granulocyte-macrophage colony-stimulating factor on Fc gamma receptor expression and antibody-dependent cellular cytotoxicity of hematopoietic progenitor cells during in vitro myeloid maturation.

Enriched progenitor cell fractions from human bone marrow were induced to undergo myeloid maturation in culture using recombinant human interleukin-3 (rhIL-3) and granulocyte-macrophage colony stimulating factor (rhGM-CSF). A negative selection method using the murine monoclonal antibodies (MABs) PM81 (anti-CD15), AML-2-23 (anti-CD14), PC251 (anti-CD33), OKT11 (anti-CD2), and SCCL-1 (anti-CD71) and immunomagnetic beads coated with sheep anti-mouse IgG (Dynal A.S., Oslo, Norway) was used to remove the more mature cellular components of mononuclear cells from normal donor bone marrow samples. The resulting fraction of cells contained 35 to 40% CD34-positive cells, and less than 1% of cells expressed the receptors for the constant portion of immunoglobulin G Fc gamma RI or Fc gamma RII. A small population (3-5%) expressed Fc gamma RIII on day 0, and these cells were found by two-color flow cytometry to be primarily natural killer (NK) cells. The level of Fc gamma R expression was determined every 2 to 3 days on aliquots of the differentiating cells. Thirteen percent of the cultured bone marrow cells expressed Fc gamma RII after 48 hours in liquid culture with rhIL-3 and rhGM-CSF. The percent of cells expressing Fc gamma RII increased to a peak of 78% of the gated population on day 10. The mean fluorescence intensity (MFI) remained low for the first 8 to 10 days of culture, but at that time the MFI more than doubled. Fc gamma RI and Fc gamma RIII expression remained low throughout the culture period. The ability of the differentiating cells to perform antibody-dependent cellular cytotoxicity (ADCC) was determined at a single-cell level in a modified plaque assay using monolayers of ox erythrocyte (oxE) target cells. The purified progenitor cells, when placed in oxE monolayers sensitized with polyclonal rabbit anti-oxE antibody (AB), showed no plaque formation over control oxE layers. No increase in ability to generate cytolytic plaques in antibody-sensitized oxE layers was seen compared with unsensitized oxE layers until after 10 days of incubation in liquid culture. At that time, the percent of cells forming plaques in the AB-sensitized oxE layers was 34.4 +/- 10.7% (average +/- standard error of the mean [SEM]; n = 4) compared with 10.0 +/- 0.7% on the control oxE layers. The peak plaque formation appeared to coincide with the increase in MFI of a large population of the cultured cells.(ABSTRACT TRUNCATED AT 400 WORDS)

Antibodies, Monoclonal↗
PubMed1995

A synergistic increase in transplantable peripheral blood stem cells in mice by co-administration of recombinant human interleukin 6 and recombinant human granulocyte colony-stimulating factor.

We examined the effects of co-administration of recombinant human (rh) IL-6 (10 micrograms/day) and rh granulocyte colony-stimulating factor (G-CSF) (0.35 micrograms/day) on the number of peripheral blood cells and peripheral progenitor cells in mice. Among blood cells counts, only white blood cells were synergistically enhanced by co-administration of rhIL-6 and rhG-CSF. Moreover, it was found that co-administration of rhIL-6 and rhG-CSF also caused a marked synergistic increase in the number of peripheral blood progenitor cells. Namely, in combination with rhG-CSF, which alone induced a 170-fold increase in peripheral granulocyte-macrophage colony-forming units (CFU-GM) on day 14, rhIL-6 synergistically increased the number of CFU-GM to more than 1600-fold higher than the number in control mice. Administration of rhIL-6 alone induced a 46-fold increase in CFU-GM. Similar synergistic increases of other hematopoietic progenitors, such as colony-forming units in spleen and megakaryocyte colony-forming units in blood, were also observed in mice co-administered rhIL-6 and rhG-CSF. The survival rate of lethally irradiated recipient mice transplanted with mononuclear cells from 100 microliters of blood from mice administered rhIL-6 and/or rhG-CSF was examined. When mononuclear cells from mice co-administered rhIL-6 and rhG-CSF were injected, survival rate at day 100 was 92%. In contrast, recipient mice transplanted with mononuclear cells from mice administered either rhIL-6 or rhG-CSF alone showed a survival rate of 31% or 46%, respectively, although transplantation of mononuclear cells from control mice failed to rescue any lethally irradiated recipient mice. These results suggest that co-administration of rhIL-6 and rhG-CSF may be useful for peripheral blood stem cell transplantation.

Animals↗
PubMed1993

Recombinant vaccine development: a novel approach to ectoparasite control. A review of development of a recombinant vaccine for hypodermosis based on hypodermin A.

Cattle grubs (Hypoderma lineatum and H. bovis) are obligate parasites of cattle for most of their one year life cycle. Previously exposed animals become resistant to productive reinfestation, presumably as a result of immune system involvement, suggesting potential control by vaccination. Research progress towards development and utilization of a recombinant subunit vaccine for hypodermosis is described.

Animals↗
PubMed1995

Murine T and B cell responses to natural and recombinant hornet venom allergen Dol m 5.02 and its recombinant fragments.

White-face hornet venom allergen, Dol m 5.02, is a protein of 204 amino acid residues. This protein and its overlapping fragments, of 53-114 residues in size, containing the N-terminal, middle, and C-terminal regions of the molecule, can be expressed in high yield in bacteria by using the plasmid vector pQE12. Natural (n) and recombinant (r) Dol m 5.02s and the r-fragments are about equally immunogenic for IgG Ab response in BALB/c mice. n-Dol m 5.02 induces mainly murine IgG Abs specific for its discontinuous B cell epitopes and, to a lesser extent, Abs specific for its continuous epitopes. r-Dol m 5.02 and the r-fragments induce only Abs specific for continuous B cell epitopes that are common with those of the n-protein. Abs specific for the discontinuous epitopes show higher affinity than those specific for the continuous epitopes. r-Dol m 5.02 and the r-fragments are as efficient as n-Dol m 5.02 in inducing murine T cell responses specific for the n-protein. The differences in the immunogenicity of n- and r-proteins or r-peptide fragments for B and T cell responses are related to their conformations, inasmuch as only the n-protein is cross-linked by four disulfide bonds. These findings are relevant to the potential use of r-fragments as immunotherapeutic reagents in humans.

Allergens↗
PubMed1994

Therapeutic efficacy of recombinant interleukin-6 (IL-6) alone and combined with recombinant human IL-3 in a nonhuman primate model of high-dose, sublethal radiation-induced marrow aplasia.

Using a nonhuman-primate model of radiation-induced bone marrow aplasia, we examined whether the single, concomitant, or sequential administration of recombinant human interleukin-3 (IL-3) and IL-6 would promote bone marrow regeneration measured by an increase in circulating platelets (PLT) and neutrophils (PMN). Rhesus monkeys were irradiated at 450 cGy and were randomly assigned to one of five treatment protocols, receiving IL-6; IL-3; combined IL-6 and IL-3; sequential IL-3 and IL-6; or human serum albumin (HSA) as a control. Cytokines or HSA were administered at total dosages of 15 micrograms/kg/day. Complete blood counts and white blood cell differentials were monitored for 60 days postirradiation. Both IL-3 and IL-6 significantly enhanced the regeneration of PLTs and decreased the duration of thrombocytopenia (P = .005) without affecting PMN recovery. The radiation-induced anemia that was observed in the HSA-treated controls was less severe and resolved more quickly in the IL-6 treated animals. Sequential IL-3/IL-6 significantly increased the production of PLTs when compared with the HSA-treated controls (P = .003) and monkeys receiving concomitant IL-3/IL-6 (P = .041) but did not alter PMN levels significantly (P = .80). Coadministration of IL-6 and IL-3 did not enhance PLT but improved PMN recovery over IL-6 alone. In this primate model of marrow aplasia, IL-6 significantly enhanced the regeneration of PLTs but had no significant effect on PMN production, and did not exacerbate radiation-induced anemia. Furthermore, the use of sequentially administered IL-3 and IL-6 may improve PLT recovery as compared with concurrent IL-3/IL-6 administration, although this protocol is not significantly different in effect than either cytokine alone.

Anemia↗
PubMed1976

[Mechanism of genetic recombination during bacterial recombination. VI. Single-stranded conjugation].

The mutation BT43 in the dnaB gene inhibits conjugational DNA synthesis in the recipient cell at 42 degrees C. Since only one DNA strand is transferred from the donor to the recipient in these conditions, this single strand is integrated into the recipient chromosone. This is characterized by a high increase of recombination frequency per length unit, an effect well known in the case of transformation. This peculiar genetic process is proposed to be called "single stranded conjugation". It is more efficient in recipient cells recB-recC-sbcB-lacking two main degrading enzymes, exonucleases I and V. The proof of single strandedness was given by means of clonal analysis in a special experiment. The transfer of the selected marker into the thermosensitive recipient took place at 37 degrees C and the transfer of the non-selected marker -- at 42 degrees C. Thhe progeny of one merozygote must be mixed i.e. consist of cells with both alleles of the non-selected marker. This was confirmed by experimental data.

Conjugation, Genetic↗
PubMed1993

Tests for the fractional active-site model in Flp site-specific recombination. Assembly of a functional recombination complex in half-site and full-site strand transfer.

The Arg191-His305-Arg308 (the RHR triad) and Tyr343 of Flp site-specific recombinase correspond to the invariant tetrad residues of the integrase family of proteins. Flp mutants altered at these positions are blocked at the strand cleavage or the strand exchange step of recombination. Hybrid half-site-recombinase complexes formed by step-arrest mutants of Flp have revealed that an Flp monomer occupying a half-site does not cleave that half-site but rather cleaves a half-site occupied by a second Flp monomer. This trans-DNA cleavage is neatly accommodated by a model in which an Flp active site is assembled by contribution of amino acid residues from at least two protein monomers. Using a combination of wild type Flp, single, double, and triple step-arrest Flp mutants, critical predictions of the fractional active-site model have been verified. First, a wild type monomer paired with an RHR triad-Tyr343 double mutant is a catalytically inactive combination. Second, each pairwise combination of a single, double, or triple RHR mutant with Flp (Y343F) yields approximately equivalent levels of catalytic complementation. Half-site to half-site and half-site to full-site crosses suggest that execution of a strand transfer event within a half-site and between a half-site and a full site requires dimeric and tetrameric Flp configurations, respectively.

Amino Acid Sequence↗
PubMed1996

The loss of recombinant human granulocyte colony-stimulating factor and recombinant human TNF-alpha priming effects on the superoxide-generating response in exudated neutrophils is associated with a decrease in their receptor affinities.

Several cytokines are known to enhance FMLP-stimulated superoxide generation in human circulating blood neutrophils through binding to their specific receptors, a process referred to as the priming effect. The priming effects produced by recombinant human granulocyte CSF (rhGCSF) and TNF-alpha (rhTNF-alpha) on FMLP-stimulated superoxide production in human and rabbit blood neutrophils were compared with their effects in their respective tissue neutrophils, i.e., human salivary and rabbit peritoneal neutrophils. The receptor binding characteristics of rhGCSF and rhTNF-alpha were also compared between the two types of neutrophils. Both rhGCSF and rhTNF-alpha produced dose-dependent priming effects on FMLP-stimulated superoxide production in human blood neutrophils, whereas they failed to produce any priming effects in human salivary neutrophils. Similar results were obtained for the priming effects by rhGCSF in rabbit blood and peritoneal neutrophils. A decrease in receptor binding affinity, but not in receptor density, in tissue neutrophils was demonstrated by analyzing the binding of [125I]rhGCSF and [125I]rhTNF-alpha. These findings suggest that tissue neutrophils are less responsive to rhGCSF and rhTNF-alpha in the modulation of FMLP-stimulated superoxide generation. This is due at least in part to the lower affinities of GCSF and TNF-alpha to their receptors in tissue neutrophils. This marked difference in priming effects by cytokines between blood and tissue neutrophils may represent an early step in the defensive responses against invading microorganisms or Ags.

Animals↗
PubMed1997

Effects of recombinant human insulin-like growth factor-1 and recombinant human growth hormone on anabolism and immunity in calorie-restricted alcoholic rats.

UNLABELLED: Patients with severe alcoholic liver injury exhibit very low serum insulin-like growth factor-1 (IGF-1) concentrations, along with many of the symptoms that might occur with an IGF-1 deficiency state (including severe protein calorie malnutrition and immunosuppression). This study was performed to assess the effects of recombinant human (rh) IGF-1 and/or rh growth hormone (rhGH) on anabolism and immunity in the calorie-restricted, immunosuppressed alcoholic rat. METHODS: Undernutrition was induced by calorie restriction such that each animal consumed 40% of ad libitum-fed controls. Alcohol was administered orally in the diet such that the mean daily intake was 9.4 g/kg/day. rhIGF-1 was administered by continuous subcutaneous infusion (380 micrograms/day) using a 14-day miniosmotic pump; rhGH was given by subcutaneous injections (400 micrograms/day). Matching placebo groups were also studied. RESULTS: On this regimen, ad libitum-fed controls were well nourished and increased body weight 34%, whereas Restricted controls lost 7.7% and Restricted alcohol-fed rats lost 15.2%. Significant but incomplete reversal of undernutrition was achieved with hormone therapy. Best improvement was obtained with combined therapy: rhIGF-1 + rhGH (p < 0.005; placebo versus active treatments). Immunologic impairment was observed to be severe in both thymus and spleen. The most severe changes were seen in thymi of the calorie-restricted, alcohol-fed rats, wherein 98% of the T lymphocytes were lost. rhIGF-1 treatment, but not rhGH, produced significant improvements in thymus. This was most pronounced in control rats (p < 0.005). Splenic T lymphocytes were less impaired and were more responsive to rhIGF-1 treatment; there was a maximum loss of 71% of T cells in Restricted, alcohol-fed rats. rhIGF-1 treatment completely restored splenic cellularity, as well as each of the T lymphocytes studied: CD5, CD4, and CD8. Functional status of splenic T lymphocytes was assessed by blast transformation after concanavalin A stimulation. Calorie restriction did not impair significantly this function in controls [Lieber-DeCarli control diet (LCD)]. However, it was significantly impaired in the Restricted, alcohol-fed rats (p = 0.003). In the presence of continued calorie restriction and alcohol, this function was not restored with either hormone (rhIGF-1 and/or rhGH). Their role in facilitating functional recovery after calories is restored, and alcohol is discontinued is under investigation.

Alcoholism↗