Immunomodulatory effect of thymopentin on lymphocytes from supramammary lymph nodes of dairy cows

Previous study showed that injection of thymopentin (TP 5) in the area of supramammary lymph nodes (SMLN) had therapeutic effect on the intramammary infection (IMI) in cows. This study was to explore the underlying mechanisms by investigating the immunomodulatory effect of TP 5 on SMLN lymphocytes. Lymphocyte proliferation, cell cycle distribution and cytokine mRNA expression were determined by MTT, FCM and RT-qPCR, respectively. Laser scanning confocal microscope (LSCM) was used to observe the binding between TP 5 and SMLN lymphocytes. Moreover, RNA-sequencing (RNA-seq) was performed to observe the difference between the lymphocytes with and without TP 5 treatment. The results showed that TP 5 significantly promoted lymphocyte proliferation, accelerated cell cycle progression, and enhanced mRNA expression of IL-17A and IL-17F. Laser scanning confocal microscopic analysis revealed the binding of TP 5 to the surface of SMLN lymphocytes. A total of 1094 genes were identified as differentially expressed genes (DEGs) using RNA-seq with 692 up- and 402 down-regulated genes. 48 significantly enriched GO terms were identified by RNA-seq. In KEGG analysis, 1/3 of DEGs were enriched in the immune system pathway, including IL-17 signaling pathway, cytokine-cytokine receptor interaction, Th1 and Th2 cell differentiation, T cell receptor signaling pathway, Th17 cell differentiation. Among them, IL-17 signaling pathway was the most prominent. This study suggested that the therapeutic benefit of TP 5 in the treatment of bovine mastitis might be attributed to its immunomodulatory activity in SMLN lymphocytes.

Sequential Subcutaneous Thymopentin, Interferon Alpha-2A and Interleukin-2 in Metastatic Renal Cell Cancer

To determine the activity of sequential administration of thymopentin (TP-5), interferon alpha-2a (IFN) and interleukin-2 (IL-2) in metastatic renal cell cancer (RCC), 17 patients with RCC were treated with TP-5 50 mg/d on days 1 to 14, IFN 3 MIU/d on days 14, 15, 21, 22 and IL-2 18 MIU/d on days 16 to 20, and 23 to 27. Treatment was given subcutaneously and cycles were repeated every 6 weeks. All patients were assessed for toxicity and response. No objective responses were observed. Two patients had a short-lived disease stabilization. Median survival was 9 months. Toxicity was generally moderate. The most important side-effects were related to IL-2 administration. In view of the lack of antitumor activity, the combination of TP-5 + IFN + IL-2 in the doses and schedule used in this trial cannot be recommended. The investigation of chemotherapeutic and immunological agents that can effectively synergize with IFN or IL-2 is essential.

Vesicular phospholipid gels using low concentrations of phospholipids for the sustained release of thymopentin: pharmacokinetics and pharmacodynamics

Vesicular phospholipid gels (VPGs) with high concentrations of phospholipids are used as implantable depots for sustained release of drugs due to high viscosity. This study aimed to investigate VPGs with low concentrations of phospholipids for subcutaneous injection and sustained release in vivo. A small peptide, thymopentin, was selected and incorporated into various VPG formulations. The VPG viscosity was greatly increased with higher concentrations of phospholipids (E80) and thus VPGs based on low lipid contents are more suitable for injection. Additionally, VPGs loaded with 5-hydroxy-fluorescein-thymopetin (5-FAM-TP5-VPGs) were developed and their pharmacokinetic profile was investigated in vivo. After subcutaneous injection, the release time of 5-FAM-TP5 was 216 h for 5-FAM-TP5-VPGs (containing 300 mg/g lipid), which was much longer than that of 5-FAM-TP5 solution. The therapeutic efficacy of TP5-VPGs (containing 300 mg/g lipid) after subcutaneous administration once a week was demonstrated to be comparable to that of TP5 solution injected subcutaneously once daily for 7 days. In conclusion, TP5-VPGs with low lipid content (300 mg/g) displayed sustained release properties in vivo that may serve as a sustained delivery system for subcutaneous injection.

Multivesicular liposomes for the sustained release of thymopentin: stability, pharmacokinetics and pharmacodynamics

The objective of the present study was to investigate the storage stability of thymopentin multivesicular liposomes (TP5-MVLs) prepared with different emulsifiers, and to study the pharmacokinetics and pharmacodynamics of the produced TP5-MVLs in vivo. The stability studies of TP5-MVLs indicated that MVLs particles prepared with mixed emulsifiers (Myrj52:solutolHS15 = 2:3) were stable at the storage temperature of 4 +/- 2 degrees C within 3 months. In addition, FITC-TP5-loaded MVLs was prepared for pharmacokinetic studies that after subcutaneous administration, the fluorescence signal lasted for about 5 days in plasma demonstrating that the rate of drug release from MVLs was very slow. The pharmacodynamic studies indicated that the therapeutic efficacy of TP5-MVLs after subcutaneous administration once every four days was the same as free TP5 solution after intravenous or subcutaneous administration once daily. In conclusion, MVLs, which possessed great storage stability, can be utilized to reduce the administration frequency of TP5, and therefore, served as a promising sustained release delivery system for polypeptide.

Box-Behnken optimization design and enhanced oral bioavailability of thymopentin-loaded poly (butyl cyanoacrylate) nanoparticles

This study was done to prepare thymopentin (TP5)-loaded poly (butyl cyanoacrylate) nanoparticles (TP5-PBCA-NPs) and evaluate thier efficacy for oral delivery. TP5-PBCA-NPs were prepared by emulsion polymerization, and the formulation was optimized based on Box-Behnken experimental design. The physico-chemical characteristics of TP5-PBCA-NPs were evaluated using transmission electron microscopy (TEM), malvern zetasizer, Fourier transform infra-red spectroscopy (FT-IR) and differential scanning calorimetry (DSC). The encapsulation efficiency, enzymatic degradation and release behavior of TP5-PBCA-NPs in various media were evaluated using a high-performance liquid chromatography (HPLC) method. The pharmacodynamic studies on oral administration of TP5-PBCA-NPs were performed in FACScan flow cytometry. An optimum formulation consisted of 0.7% poloxamer 188 (Pol), 0.6% dextran-70 (Dex), 0.1% sodium metabisulfite (Sm), 0.1% TP5 and 1% (v/v) n-butyl cyanoacrylate. The particle size and zeta potential of optimized TP5-PBCA-NPs was 212 nm and -22.6 mV respectively with 82.45% encapsulation efficiency. TP5 was entrapped inside the nanoparticles in molecular dispersion form. The release of TP5 from PBCA-NPs was pH dependent; the cumulative release percentage in 0.1 M HCI for 4 hours was less than 16% while it was more than 80% in pH6.8 PBS. The PBCA-NPs could efficiently protect TP5 from enzymatic degradation; the remained percentage of TP5 encapsulated in PBCA-NPs was 58.40% after incubated with trypsin in pH6.8 PBS for 4 h while it was only 32.29% for free drug. In the oral administration study in vivo, the lowered T-lymphocyte subsets values were significantly increased and the raised CD4+/CD8+ ratio was evidently reduced compared with that of TP5 solution (p < 0.05), and the improvement of bioavailability was dose-dependent. These results indicated that the PBCA nanoparticles may be a promising carrier for oral delivery of TP5.

Preparation and evaluation of poly-butylcyanoacrylate nanoparticles for oral delivery of thymopentin

Thymopentin (Tp5) was loaded in poly-butylcyanoacrylate (PBCA) nanoparticles (NP) in order to enhance the oral bioavailability of Tp5. PBCA-Tp5-NP was prepared by nanoprecipitation methods. Dialyzing membrane method was employed to examine the in vitro release of PBCA-Tp5-NP in PBS, and Tp5 samples in the release medium were detected by HPLC. The cell proliferation test (³H-thymidine) was conducted to verify the PBCA-Tp5-NP bioactivity in vitro. The pharmacodynamical studies were performed on preimmunoinhibited rats and in flow cytometer. The size and the entrapment efficiency of PBCA-Tp5-NP were 178 ± 39 nm and 92.21 ± 1.08%, respectively. In vitro release data show that less than 60% Tp5 was released from lyophilized PBCA-Tp5-NP while 80% Tp5 was released from the colloidal PBCA-Tp5-NPs in 48 h. The proliferation test showed that PBCA-Tp5-NP had the similar effect as Tp5. The in vivo data showed that oral PBCA-Tp5-NPs had similar function as what intravenous Tp5 did. The oral bioavailability of Tp5 could be enhanced by PBCA nanoparticles. PBCA-Tp5-NP had the property of sustained-release and the efficacy of Tp5 was not changed after formulation.

[Preparation of sustained release multivesicular liposome for thymopentin and preliminary study on its pharmacokinetics in rats]

To optimize the formulation and preparation method of multivesicular liposome of thymopentin and to investigate its pharmacokinetics in rats, the multivesicular liposome of thymopentin was prepared by double emulsification method and the formulation was optimized by orthogonal design. The release characteristics of thymopentin from multivesicular liposome in PBS (pH 7.4) and in plasma were investigated. The multivesicular liposome of thymopentin labeled with fluorescein isothiocyanate was prepared by double emulsification method. Its pharmacokinetics was evaluated following intramuscular injection in rats. The optimal formulation of multivesicular liposome of thymopentin were formulated with 7.5% glucose in aqueous phase and 2.25 mol x L(-1) triolein, 2.68 mol x L(-1) DPPG and 16.96 mol x L(-1) DOPC in organic phase. The entrapment efficiency of the multivesicular liposome of thymopentin was above 85% and the mean particle size was about 22 microm. The in vitro release of thymopentin from multivesicular liposome in PBS (pH 7.4) and in plasma was found to be in a sustained manner. The release curves were fitted to Higuchi equation. The pharmacokinetics following intramuscular injection of the multivesicular liposome of thymopentin labeled with fluorescein isothiocyanate in rats showed that the peak concentration of thymopentin was lower and elimination of it was slower significantly than that of thymopentin labeled with fluorescein isothiocyanate solution in the same dose. The plasma concentration of thymopentin maintained above quantitative limitation at 120 h after administration of multivesicular liposome of thymopentin. The optimized formulation and preparation technology of multivesicular liposome of thymopentin with higher entrapment efficiency are feasible with good reproducibility. Multivesicular liposome of thymopentin showed significant sustained-release property following intramuscular injection in rats.

[Study on the efficacy and safety of high dose thymopentin combined with trans-artery chemoembolization for primary liver cancer]

OBJECTIVE

To evaluate the efficacy and safety of high doses of thymopentin (10 mg/d) combined with transartery chemoembolization for primary liver cancer.

METHODS

Fifty primary liver cancer patients were randomly divided into two groups: therapeutic and control group, and all were treated with transfemoral artery chemoembolization (TACE) with oxaliplatin 150 mg, pharmorubicin 50 mg, 5-Fu 750 mg, CF 300 mg and lipiodol 20 ml. Therapeutic group (25) were added 10 mg thymopentin daily after TACE: i.v. on dl - d5, and im on D6 - D21.

RESULTS

There was a significant difference in adverse effect and toxicity such as naupathia,fever, swirl, asthenia observed between two groups (P < 0.05). No difference in either pre- or post-chemotherapy peripheral blood examination and biochemical assay was found between two groups (P > 0.05). In control group, CD4+ cell was 37.92% +/- 8.71% in pre-treatment, which decreased to 29.16% +/- 8.21% in post-treatment with a significant difference (P < 0.01), whereas there was no evident difference in CD4+ cell between pre-treatment and post-treatment in the treatment group.

CONCLUSION

Transartery chemoembolization combined with high dose of thymopentin in the treatment for primary liver cancer is effective and safe, and can significantly improve the immune function and the chemotherapy tolerance.

[Research on thymopentin-loaded N-trimethyl chitosan nanoparticles administered through mouth]

OBJECTIVE

To prepare a peroral thymopentin-loaded N-trimethyl chitosan chloride-nanoparticle (Tp5-TMC-NP) ,and observe the pharmacodynamic action when the Tp5-TMC-NP is taken by way of the mouth.

METHODS

N-trimethyl chitosan chloride was first synthesized, and then Tp5-TMC-NP was prepared with the formulation technology optimized by the Central Composite Design. The influence of Tp5-TMC-NP on the ratio of CD4+/CD8+ of T-lymphocytes were determined by flow cytometer.

RESULTS

The regular global Tp5-TMC-NP prepared with the optimized formulation craft had the mean diameter of 110.6 nm and got the entrapment efficiency of 78.8%. The ratio of lymphocyte CD4+/CD8+ of Wistar rat administered with Tp5-TMC-NP perfusing stomach had 2.59 times higher than that with Tp5.

CONCLUSION

Taken orally the Tp5-TMC-NP has much higher efficiency than Tp5.

Preparation and evaluation of lectin-conjugated PLGA nanoparticles for oral delivery of thymopentin

The purpose of this study was to design and evaluate lectin-conjugated PLGA nanoparticles for oral delivery of thymopentin. Thymopentin loaded PLGA nanoparticles (TP5-NPs) were prepared by a double emulsion-solvent evaporation technique. Novel WGA-PLGA conjugates were synthesized by coupling the amino groups of wheat germ agglutinin (WGA) to the carbodiimide-activated carboxylic groups of PLGA, and were incorporated into nanoparticles preparation to take mucoadhesive properties. Important characteristics such as particle size, zeta potential, entrapment efficiency, storage stability, as well as in vitro drug release behavior were investigated. The retention of biorecognitive activity of WGA after covalent coupling was confirmed by haemagglutination test. In vitro experiments with pig mucin (PM) demonstrated that the conjugation of WGA enhanced the interaction about 1.8-4.2 fold compared with that of the non-conjugated nanoparticles, and still exhibited sugar specificity. The pharmacodynamical studies on oral administration of WGA-TP5-NPs were performed in FACScan flow cytometry. The values of CD4(+)/CD8(+) ratios were significantly increased compared with that of TP5-NPs (p<0.01). The enhanced uptake was related to the increasing of WGA content on nanoparticles. These results confirmed that the conjugation of WGA onto PLGA nanoparticles effectively improved the intestinal absorption of TP5 due to specific bioadhesion on GI cell membrane.

Research on thymopentin loaded oralN-trimethyl chitosan nanoparticles

Peptides, although high efficacy and specificity in their physiological function, usually have low therapeutical activities due to their poor bioavailability when administrated orally. Nanoparticles have been regarded as a useful vector for targeted drug delivery system because they can protect drug from being degraded quickly and pass the gastrointestinal barriers. Here we described a novel oral N-trimethyl chitosan nanoparticles formulation containing thymopentin (Tp5-TMC-NP). N-trimethyl chitosan (TMC) was synthesized and then used to prepare Tp5-TMC-NP by ionotropic gelation. A three-factor, five-level CCD (Central Composite Design) design was used in the optimization procedure, with HPLC as the analyzing method. The resulting Tp5-TMC-NP had a regular spherical surface and a narrow particle size range with a mean diameter of 110.6 nm. The average entrapment efficiency was 78.8%. The lyophilized Tp5-TMC-NP formulation was stable in 4 degrees C or -20 degrees C after storage of 3 months without obvious changes in morphology, particle size, pH and entrapment ratio. The results of the flow cytometer determination showed that the ratio of CD4+/CD8+ of Wistar female rat givenTp5-TMC-NP (ig) was 2.59 time that of the group given Tp5 (ig).

Thymopentin-loaded pH-sensitive chitosan nanoparticles for oral administration: preparation, characterization, and pharmacodynamics

Thymopentin, a potent immunomodulating drug, was incorporated into pH-sensitive chitosan nanoparticles prepared by ionic gelation of chitosan with tripolyphosphate anions and then coated with Eudragit S100 to improve the stability and the oral bioavailability. Nanoparticles particle size and zeta potential were measured by photo correction spectroscopy and laser Dopper anemometry. Its morphology was examined by environment scan electron microscope. The encapsulation efficiency and the release in vitro were determined by HPLC. Enzymatic stabilization was expressed by the enzymatic degradation of aminopeptidase. Biological activity of TP5 loaded in nanoparticles was assayed by lymphocyte proliferation test in vitro and the immune function (CD4+/CD8+) of irradiated rat in vivo. The results obtained demonstrated that the average sizes of pH-sensitive chitosan nanoparticles were 175.6 +/- 17 nm, the zeta potential was 28.44 +/- 0.5 mV and the encapsulation efficiency was 76.70 +/- 2.6%. The cumulative release percentages of thymopentin from the pH-sensitive nanoparticles were 24.65%, 41.01%, and 81.44% incubated in different medium, 0.1 N HCl, pH 5.0 PBS, and pH 7.4 PBS, respectively. The pH-sensitive chitosan nanoparticles could efficiently protect TP5 from enzymatic degradation and prolong the degradation half-time of TP5 from 1.5 min to 15 min. It was demonstrated from the lymphocyte proliferation test that the nanoparticle-encapsulated TP5 still kept its biological activity. In immunosuppression rats, the lowered T-lymphocyte subsets values were significantly increased and the raised CD4+/CD8+ ratio was evidently reduced. These results indicated that pH-sensitive chitosan nanoparticles may be used as the vector in oral drug delivery system for TP5.

Meta-analysis: the adjuvant role of thymopentin on immunological response to hepatitis B virus vaccine in end-stage renal disease

BACKGROUND

It has been calculated that 30-40% of dialysis patients fail to produce antibodies to HBsAg antigen after vaccination towards hepatitis B virus. Several authors have reported on the benefit of thymopentin (TP5) as adjuvant to vaccine against hepatitis B virus in patients receiving regular dialysis. However, consistent information on this issue is still lacking.

AIMS

To evaluate efficacy and safety of thymopentin as adjuvant to hepatitis B vaccine in dialysis patients by performing a systematic review with a meta-analysis of clinical trials.

METHODS

We used the random effects model of DerSimonian and Laird, with heterogeneity and sensitivity analyses.

RESULTS

We identified 11 studies involving 272 unique patients with end-stage renal disease. Only prospective, controlled trials were included. Pooling of study results did not show a significant increase in seroresponse rate among study (thymopentin plus hepatitis B virus vaccine) vs. control (hepatitis B virus vaccine alone) patients; the pooled odds ratio of failure to respond to hepatitis B virus vaccine was 0.677 (95% confidence intervals: 0.285-1.605); no heterogeneity was found (P = 0.0001). Thymopentin significantly improved the seroresponse rate in the subgroup of trials based on greater thymopentin doses (OR: 0.184; 95% CI: 0.085-0.398).

CONCLUSIONS

Our meta-analysis showed that thymopentin significantly improved the seroresponse rate towards hepatitis B vaccine only in dialysis patients treated with higher thymopentin doses. The limited number of patients precluded definitive conclusions.

Pharmacokinetics, toxicity of nasal cilia and immunomodulating effects in Sprague-Dawley rats following intranasal delivery of thymopentin with or without absorption enhancers

Thymopentin (TP 5), a synthetic pentapeptide, has been used in clinic as a modulator for immnuodeficiencies through intramuscular administration. The objectives of this study was to investigate the pharmacokinetics using normal rats and toxicity of nasal cilia as well as immunomodulating effects using immunosuppression rats after intranasal delivery of thymopentin with or without an absorption enhancer. The absorption extent of fluorescein isothiocyanate (FITC) labeled TP 5 via nasal delivery at a single dose is significantly improved by incorporating sodium deoxycholate, Brij 35 and chitosan, respectively. FITC-TP 5 can also be absorbed to such an extent ranging from 15 to 28% after intranasal administration of FITC-TP 5 alone, FITC-TP 5 with sodium caprylate, or with bacitracin, respectively. After seven consecutive days multiple dosing, TP 5 formulation with sodium deoxycholate or Brij 35 caused apparently injury to nasal cilia, indicating these two enhancers would not be appropriate for nasal delivery. Results from superoxide dismutase activity, maleic dialdehyde, T-lymphocyte subsets (CD3+, CD4+, CD8+ and CD4+/CD8+ ratio) analyses suggest that all the selected enhancers improve the modulating effects of TP 5 in the immunosuppression rats. On an overall evaluation, intranasal TP 5 alone, TP 5 with chitosan, or TP 5 with bacitracin formulation may be suitable for the future clinical application.

Chemo-immunotherapy in advanced head and neck cancer

BACKGROUND

Patients with advanced squamous cell carcinoma of the head and neck (SCC) have a depressed immune system whose function is worsened by chemotherapy. In a pilot phase II study, in order to improve the immune function during chemotherapy, we combined to cisplatin (CDDP) and 5-fluorouracil (5-FU) two biological response modifiers, retinyl palmitate (R) and Thymopentin (TP-5) for the treatment of SCC.

PATIENTS AND METHODS

Fifty patients with recurrent or metastatic SCC of the head and neck were treated with Cisplatin 24 mg/m2 from day 1 to 5 and 5-FU 1,000 mg/m2 by a 120 hour continuous infusion. Retinyl palmitate was administered orally 50,000 i.u. b.i.d and Thymopentin 50 mg subcutaneously 3 times a week.

RESULTS

Chemotherapy treatment was well tolerated with G3 hematological toxicity in 30% of patients and G2 gastrointestinal toxicity in 20% of patients. 16 patients (32%) had a complete response (CR), 13 patients had partial response (PR) (26%), (response rate 58%, 95% c.i. 43%-72%); stable disease (SD) was observed in 7 patients (14%), while 14 patients progressed (PD) (28%). Median time to progression was 12 months (range 2.8-94.5). Median overall survival was 13.5 months (range 2-104).

CONCLUSIONS

The association of CDDP and 5-FU with Retinyl Palmitate and TP5 has a major activity in the treatment of advanced head and neck cancer and a relatively well tolerated toxicity.

[Thymopentin in alopecia areata]

Alopecia areata is a common cause of hair loss which leads to localized bald areas predominantly on the scalp. Etiological factors are not clear yet, but it is generally considered as a consequence of an autoimmune process. Histological findings revealed perifollicular infiltration of T-cells and antigen-presenting cells. Autoreactive T-cells are reported to amplify this abnormality by interacting with follicular epithelium. There is no effective treatment available at the moment. We report on a 53-year old climacteric woman who developed a bald lesion on her scalp spontaneously in november 1995. Alopecia areata was documented before and after therapy. Treatment with thymopentin 50 mg subcutaneously was offered successfully for 10 weeks, while continuing hormone replacement therapy. Other therapeutical strategies did not proof to be successful before.

Evaluation of clinical efficacy and tolerability of intravenous high dose thymopentin in advanced melanoma patients

Thymopentin (TP5) has been recently evaluated as an immunotherapeutic agent for the treatment of cancer. Melanoma is a highly immunogenic malignancy, and in our previous studies the treatment of metastatic melanoma with TP5 showed encouraging results. In the present study, we evaluated the clinical efficacy and tolerability of high dose intravenous TP5 in 16 patients with melanoma which had metastasized to cutaneous and subcutaneous tissue. All patients were given 1 g intravenous TP5 every second day for 7 weeks and were then evaluated; responders were given a subsequent course of 2 g intravenous TP5 every second day for 5 weeks. Six patients showed a partial response after the first course and were given the second course: one patient achieved a complete response, while the other five remained in partial response at the end of the treatment. The mean duration of response was 7.5 months. No drug side effects were observed. Histopathological and immunohistochemical evaluation of regressing metastatic nodules showed the presence of tumour-infiltrating lymphocytes, necrosis, sclerosis, intratumoral vascular proliferation and microthrombosis. Immunophenotyping of lymphoid infiltrates demonstrated the prevalence of CD4+ and CD45RO+ T-lymphocytes in one patient. We conclude that high dose intravenous TP5 three times a week may induce a clinical response in patients with cutaneous and subcutaneous metastases of melanoma without relevant side effects.

Immunomodulatory activity of G-actin fragments containing a thymopentin-like sequence

A discontinuous thymopoietin-like motif, composed of the fragments 97-111 and 277-307 of the molecule, as well as of residues Arg178 and Asn163 of G-actin was found. It was established that G-actin has an immunosuppressive activity regarding the humoral immune response. This activity is probably connected to the thymopentin-like sequence RKDLY, which is present in the 277-307 fragment of G-actin. The immunomodulatory activity of a series of peptide-partial sequences of G-actin was tested using plaque-forming cells (PFC) and delayed type hypersensitivity (DTH) tests. The investigated series consisted of five peptides: RKDLY (I), RKDLYANT (II), DVDIRKDLY (III), DVDIR (NO2)KDLY (IV), DVDIRKDLYANT (V). The peptides have the immunosuppressive activity regarding the humoral and cellular immune response.

Thymopentin loaded microsphere preparation by w/o/w emulsion technique: in vitro/ex vivo evaluation

Poly-D,L-lactide (PDLLA) and polylactide-co-glycolide (PLGA) microspheres containing thymopentin have been prepared by a water-in-oil-in-water-emulsion/solvent evaporation technique. The goal is to stabilize the active compound thymopentin, and to prolong its therapeutic activity, by embedding the drug in a polymeric matrix. The microspheres obtained have been characterized for their morphology and drug content. In-vitro dissolution tests have been performed on the microspheres. Results show that the type of polymer employed (PDLLA or PLGA) does not seem to affect microsphere morphology, while in-vitro dissolution profiles are greatly influenced by the composition of polymer matrix. Ex-vivo evaluation of PLGA microspheres performed on mouse thymocites shows that biological activity of Thymopentin is maintained after loading into PLGA microspheres.

Phase I-II study of dose intensified chemotherapy with filgrastim and thymopentin in patients with advanced cancer

BACKGROUND

Carboplatin (CBDCA), cyclophosphamide (CTX) and etoposide (VP-16) combination chemotherapy is active in many tumors. A phase I-II study was designed in order to verify toxicity, maximum tolerated dose and activity of CBDCA, CTX and VP-16 given with Granulocyte Colony Stimulating Factor (G-CSF) and thymopentin (TP5), without bone marrow support.

MATERIALS AND METHODS

A group of 12 heavily pretreated patients (PTS), 9 breast cancer, 2 small cell lung cancer and 1 gastric cancer, received fourteen courses of the described combination chemotherapy. Previous treatments were as follows: surgery in 10 PTS, radiotherapy in 7 PTS, chemotherapy in all PTS (median of 9 courses per patient). CBDCA, CTX, VP-16 were given over 3 days. CBDCA doses were calculated and expressed with the area under the concentration versus time curve (AUC). The dose range were as follows: CBDCA AUC 5.5-11 (400-800 mg/m2), CTX 1500-2500 mg/m2, VP-16 450-550 mg/m2, G-CSF was given 5 mg/kg/day from day 4 to day 17. TP5 was given, on alternate days, 1 mg/ kg from day 4 to day 30.

RESULTS

6 PTS developed fever > 38 degrees C for a median (M) duration of 4 days. 4 PTS required platelet support (M of 12 units) and 3 PTS red blood cells support (M of 2 units). Maximum tolerated dose was CBDCA AUC of 8, CTX 2000 mg/m2 and VP16500 mg/m2. No treatment related death occurred. Ten patients had responses and two had disease stabilisation. At the present time 5 PTS are alive and median overall survival is 13 months.

CONCLUSIONS

These data indicate that dose intensified CT with the support of G-CSF and TP5 may be delivered safely and shows activity in heavily pre-treated patients.

Topical thymopentin therapy in HIV positive patients with recurrent oral candidiasis: a pilot study

Oral candidiasis frequently occurs in HIV-positive patients especially in those with advanced disease. To date, common anti-mycotic drugs are unable to prevent relapses and alternative therapy is necessary to reduce disabling effects. With the aim of verifying whether thymic hormone extract may be efficacious in these subjects, we enrolled 10 HIV-positive patients with recurrent and/or persistent oral candidiasis to be treated with thymopentin (oral inhalations). All patients benefited from the topical use of thymopentin, and in all cases there was marked increase in salivary secretory IgA which possibly accounted for the candidiasis improvement.

Sequential biochemotherapy for metastatic colorectal cancer using fluorouracil, folinic acid, thymopentin and interleukin-2: clinical and immunological effects

BACKGROUND

A phase II study was performed to evaluate the clinical and immunological effects of a regimen of fluorouracil (5-FU) and folinic acid (FA) combined with thymopentin (TP-5) and interleukin-2 (IL-2) in the treatment of patients with metastatic colorectal cancer.

PATIENTS AND METHODS

Forty-five evaluable patients with measurable colorectal cancer and no prior therapy for metastatic disease were treated with 5-FU 400 mg/m2/d and FA 200 mg/m2/d i.v. on days 1-5, TP-5 50 mg s.c. on days 8-11, and IL-2 9 MU/m2 s.c. twice daily on days 12-16. Cycles were repeated at 4-week intervals if toxicity had resolved. Immunological changes were evaluated in 13 patients and compared with a well matched series of 13 patients treated with the same regimen without TP-5.

RESULTS

Two complete responses and 17 partial responses were seen (42%; 95% confidence interval, 28% to 56%). Fifteen patients (33%) had stable disease. The median time to progression was 8.5 months and the median survival 13 months. Treatment was reasonably well tolerated, and there was no overlapping toxicity or interference between chemotherapy and biotherapy. Hematological and immunological changes during treatment were qualitatively similar to those expected with IL-2 +/- chemotherapy. Quantitatively, significant changes (higher levels of IL-2, CD25 and IFN-gamma, and lower levels of sIL-2R) were observed in patients given TP-5.

CONCLUSION

The combination of 5-FU + FA and TP-5 + IL-2 is effective in advanced colorectal cancer with acceptable toxicity. Immunological data suggest that TP-5 may modulate the action of IL-2 in the clinical setting. However, improved treatment approaches are needed, and the interactions between thymic hormones and cytokines should be further explored.

[Role of thymopentin in the prevention of post-splenectomy infections]

The Authors evaluated the efficacy of thymopentin in the prevention of post-splenectomy infections. 14 splenectomized patients treated by thymopentin (50 mg s.c. every other day in the 4 weeks following splenectomy) were compared with 14 splenectomized control patients. Clinical evaluations and measurement of CD4 and CD8 lymphocyte subpopulations were made preoperatively and then after 3 and 6 months from splenectomy. Hyperthermia (37.5-38 degrees C) "sine materia", which disappeared spontaneously in 4-5 weeks, was observed in the post-operative phase in 4 control patients and in 1 patient treated by thymopentin. No statistical difference was demonstrated comparing pre- and post-operative percentages of CD4 and CD8 lymphocytes in the treated and control groups.

Safety and efficacy of thymopentin in zidovudine (AZT)-treated asymptomatic HIV-infected subjects with 200-500 CD4 cells/mm3: a double-blind placebo-controlled trial

Thymopentin, 50 mg subcutaneously (s.c.) 3 times per week, was evaluated in a double-blind, randomized, placebo-controlled trial of zidovudine (AZT)-treated asymptomatic human immunodeficiency virus (HIV)-infected subjects with 200-500 CD4 cells/mm3 at entry. The 352 subjects were prestratified by prior AZT use into stratum I (235 subjects, > 6 months AZT at entry) and stratum II (117 subjects, < or = 6 months AZT at entry). Clinical end points, CD4 cell counts, serum p24, serum immune complex dissociated (ICD) p24, and safety variables were evaluated through 48 weeks, using an intent-to-treat analysis. The two strata were analyzed individually because they yielded different clinical outcomes, with a statistically significant treatment-by-stratum interaction. In stratum I (mean, 16 months AZT at entry) two AIDS or death events occurred in thymopentin and 10 in placebo recipients (p = 0.024; relative risk (RR) estimate, 4.9 [95% confidence limit (CI), 1.1 to 22.2]). There were three AIDS-related complex (ARC), AIDS, or death events in thymopentin and 18 in placebo recipients [p = 0.001; RR estimate, 5.9 (95% CI, 1.7 to 20.0)]. In stratum II (mean, 3 months AZT at entry), four AIDS or death events occurred in thymopentin and none in placebo recipients (p = 0.11), and four ARC, AIDS, or death events occurred in thymopentin and two in placebo recipients (p = 0.79). The treatment groups did not differ significantly with respect to changes in CD4 counts or p24 antigen levels or with respect to clinical adverse experiences or laboratory abnormalities. Thus, AZT-experienced placebo-treated subjects had relatively high progression rates to AIDS or death and to ARC, AIDS, or death, and these rates were reduced by thymopentin treatment. In contrast, placebo-treated subjects with little prior AZT experience had low progression rates; these were not significantly changed by thymopentin treatment. There was no increase in the incidence of adverse reactions with thymopentin.

[Changes in immune status due to anesthesia and surgical intervention. The role of thymopentin and interleukins]

OBJECTIVE

Purpose of the study was clinical evaluation of thymopentin and interleukins in the changes of immunity due to anesthesia and surgical operation.

DESIGN

After randomization the patients were divided into four groups according to starter type (thiopental or propofol) and immunological pre-treatment (tymopentin or saline of control group) administered for three days before and two days after operation.

SETTING AND PATIENTS

The study was effected on 40 patients undergoing venous vascular surgery in operating rooms of Medical School of University of Genoa.

MEASUREMENT

At pre-established times (basal, before and after induction, recovery and 72 postoperative hours) were measured some immunological data (plasmatic concentrations of red blood cells, white blood cells, lymphocyte cells, antibodies, complement analysis, interleukins 1 and 2).

RESULTS

The results show a depression of immunity with hypoleucocistosis and hyperlymphocytosis due to surgical trauma or to anesthesia drugs.

CONCLUSIONS

Pre-treatment with thymopentin no change perioperative immunity and the role of interleukins isn't clear; the immunological depression is the same in thiopental of propofol groups.

Long-term thymopentin treatment in systemic scleroderma

A study was carried out to investigate whether thymopentin treatment is capable of inducing changes in the immunological status of patients with systemic scleroderma and to compare any such changes with modifications in clinical condition. Nine patients were given thymopentin, 1 ml in 10 ml saline solution, by slow intravenous infusion 3-times weekly for 5 weeks (cycle). The cycles were repeated at 3-month intervals. Treatment duration ranged from 1 to 5 years. Blood samples were drawn at the beginning and at the end of each cycle and the patients' lymphocytic sub-populations were examined. A control group of 9 comparable healthy subjects were similarly tested. Data analysis showed that a statistically significant decrease of CD16+ and CD25+ lymphocytes compared to pretreatment was already apparent at the end of the first thymopentin treatment cycle. An improvement was found in the clinical condition of 7 of the 9 patients at the end of the follow-up period with a significant correction of unbalanced lymphocytic subsets.

Perinodular injection of thymopentin (TP5) in cutaneous and subcutaneous metastases of melanoma

The potential therapeutic efficacy of TP5 in patients with cutaneous and subcutaneous metastases of melanoma was tested in a double-blind study comparing the drug and placebo injected perinodularly. Of the 47 nodules present in the 16 patients treated with TP5, 24 showed a measurable response, whereas only one out of 15 nodules in patients treated with a placebo showed a minor response (P = 0.02). In two patients treated with TP5 a response of two nodules not perinodularly injected was also observed. Sclerosis, CD45RO+ cells and MIB 1- cells were more frequently observed in nodules treated with TP5 than with placebo. (P = 8 x 10(-4); 0.03 and 0.01, respectively). Evaluating the trends of these findings in nodules treated with placebo; with TP5-treated, non-responding nodules; or with TP5-treated, responding, a positive trend was observed for sclerosis and CD45RO+ cells (P = 5 x 10(-4) and 2 x 10(-3), respectively) and a negative one for MIB 1 cells (P = 2 x 10(-3)). These preliminary data suggest that lymphoid cells associated with nodules regression are activated large lymphocytes (CD45RO+ and CD3-). Sclerosis might be interpreted as the final morphologic event, and reduction of proliferative activity (MIB 1- cells) as the consequence of cytolytic action.

Successful restoration of cell-mediated immune response after cardiopulmonary bypass by immunomodulation

The objectives of this prospective randomized trial were to quantify immunosuppressive effects of cardiopulmonary bypass, to identify mechanisms responsible for postoperative immunosuppression, and to investigate the effects of immunomodulatory intervention on these mechanisms. Sixty patients were studied after cardiopulmonary bypass. Immunomodulatory therapy consisted of the cyclooxygenase inhibitor indomethacin, which blocks the downregulating agent prostaglandin E2, and thymopentin, which enhances T-lymphocytic activity. Twenty patients each received indomethacin either alone or combined with thymopentin. Twenty patients served as the control population. Our in vitro studies showed a decrease of CD4+ helper/inducer T cells and interleukin-2 receptor expression on T lymphocytes, while CD8+ suppressor/cytotoxic T cells and monocytes increased. Additionally, a depression of interleukin-1 and interleukin-2 synthesis as well as concurrent low gamma-interferon serum concentrations could be documented. These results indicate a downregulation of cell-mediated immune response. As an in vivo correlate of the immunomechanistic alterations, patients demonstrated an impaired delayed-type hypersensitivity response to an antigen skin test battery. These changes in immunoreactivity could be successfully counteracted by the combined immunomodulatory regimen, whereas sole indomethacin treatment could only partially restore depressed host defense parameters. With this study we could demonstrate for the first time that human lymphocytic interleukin-2 synthesis, which represents the key event among forward regulatory immune mechanisms, can be protected via in vivo immunoaugmentatory therapy and that this therapy can successfully counteract immunosuppressive effects of cardiopulmonary bypass.

[Partial remission of non-Hodgkin's lymphoma (stage IV-B) following immunostimulating therapy with thymopentin]

Therapy of low-grade of malignancy non-Hodgkin's lymphoma in an advanced stage is still under discussion: aggressive poly-chemotherapies, such as radiotherapy and conventional chemotherapies did not prove to be more effective than conservative treatments. We report the case of a woman suffering from a low-grade of malignancy non-Hodgkin's lymphoma (stage IV-B). She was in such bad general conditions that she could not be treated with chemotherapy. She received an immunostimulating drug, thymopentin for 10 months. After this treatment, the general condition of the patient was improved and a partial remission of the lymphoproliferative disease was observed. The patient is still in constant fairly good health.

Use of immunomodulators (thymopentine) in hepatitis B vaccine in elderly patients undergoing chronic hemodialysis

Thymopentine is a synthetic immunomodulator that positively affects T-lymphocyte maturation, reproduction and differentiation. In elderly uremic patients nonresponders to hepatitis B vaccine, the administration of this drug has been shown to improve the response to the new vaccination.

Evaluation of treatments for the vaccination against hepatitis B + thymopentine

We have studied a series of 43 patients--who were suffering from uremia, subject to hemodialysis treatment, resulting seronegative to the test for HBV and who had never been vaccinated before--considering the HBS antibody as seroconversion index. We subdivided our patients into three groups, according to the treatment employed. First group: French vaccine; 2nd group: French vaccine+thymopenthine; 3rd group: recombining DNA vaccine+thymopentine. From a statistical point of view, in the 3rd group we obtained a significant seroconversion in terms of patients, if compared with the other groups.

[Clinical experiences with thymopentin administered by intra- and periarticular routes in degenerative pathology of the shoulder, knee and hip]

The aim of this study was to assess the efficacy and tolerability of thymopentin, a synthetic pentapeptide with an immunomodulating action, in treating patients suffering from gonarthrosis, coxarthrosis and scapolo-omeral periarthritis by evaluating pain when resting, during activity and in response to digital pressure. Painful symptoms, quantified according to Scott-Huskisson's scale, disappeared in the majority of patients two months after the end of treatment. No collateral effects were recorded. Thymopentin may therefore be put forward as a useful alternative to cortisone compounds in the treatment of not severe degenerative joint pathologies.

[Evaluation of the use of thymopentin in patients with progressive systemic sclerosis]

Although the exact etiology of progressive systemic sclerosis (SSP) is still unknown, it is felt that immunologic disorders may be implicated in its pathogenesis. On the basis of these considerations, an open study with an immunomodulating drug, thymopentin, was performed in 20 SSP outpatients. These subjects were initially treated with thymopentin three times a week for three consecutive months (phase I); during a second study phase lasting three months, 10 patients continued to receive thymopentin and the remaining 10 placebo (phase II). A significant improvement in various clinical, laboratory and instrumental findings was seen following thymopentin treatment. During phase II, those on placebo regressed to basal conditions, while an added improvement was noted in those who continued with thymopentin.

Alopecia totalis: is treating nonresponder patients useful?

The purpose of this study was to assess the effectiveness of different treatments in patients with alopecia totalis or universalis who did not respond to sensitizing therapies. Twenty-six patients, who had been receiving sensitizing therapy for at least 1 year without any response, were randomly assigned to receive the following treatments: topical 10% cyclosporine in oily solution (eight patients), PUVA (eight patients), and intravenous thymopentin (ten patients). None of them had any acceptable regrowth after at least 6 months of treatment. Our results suggest that other treatments are not useful in patients with 100% hair loss who fail to respond to sensitizing therapies.