Advanced Therapy Medicinal Products Challenges and Perspectives in Regenerative Medicine

Recently, the design and development of a modern health policy in the field of regenerative medicine leads to the formation of a new and integrated cognitive field, which requires systematic research and study in order to produce innovative answers and best practices. Advanced therapy medicinal products (ATMPs) is a new product category, which is at the heart of concern since it has to deal with diseases in which traditional medicine has proven to be ineffective so far. The aim of this review is to provide evidence for the state of the art ATMPs and their modern applications in the field of regenerative medicine. The ATMPs are characterized by a great heterogeneity and variation in methods of isolation, which cover the entire spectrum from a single intravenous injection to a surgical placement. Clinical development of ATMP encounters specific challenges due to the nature of the product and the limited availability of non-clinical data. The gold standard of a controlled, randomized, clinical trial may not be feasible or ethically justified for all indications, particularly in life-threatening diseases, where there is no satisfactory standard of care. Therefore, the European Commission (EC) took initiatives in order to set standards and operating rules concerning authorization and supervision of ATMPs and on pharmacovigilance in relation to them. The European Union (EU) Regulation 1394/2007 provides the possibility of exceptions. In particular, the “hospital exemption” allows for the administration of an ATMP without a license on certain conditions. Although the Regulation 1394/2007 has led to the commercial exploitation of ATMPs, the reality today, 11 years after its first implementation, is completely different. While the Committee for Advanced Therapies (CAT) has already registered 285 products as ATMPs, only 10 licenses were granted which only remained six (the rest related to products withdrawn). The key players in the development and delivery of ATMPs still remain the academic/research centers and small and medium-sized enterprises; while the involvement of pharmaceutical companies is focusing on recent developments in the treatment of oncological incidents with in vitro modified cytotoxic T lymphocytes, and chimeric antigen receptor (CAR)-T cells.

Noninherited maternal antigens do not increase the susceptibility for familial rheumatoid arthritis. European Consortium on Rheumatoid Arthritis Families (ECRAF)

OBJECTIVE

It has been proposed that noninherited maternal HLA-DR antigens (NIMA) might play a role in the susceptibility for rheumatoid arthritis (RA). This hypothesis has not been thoroughly tested in patients with familial RA, in whom genetic factors, either inherited or not, might have stronger influence than in patients with sporadic RA. We investigated the NIMA hypothesis in a large cohort of European patients with familial RA.

METHODS

The distribution of NIMA, noninherited paternal antigens (NIPA), and inherited HLA-DR antigens was assessed in patients with familial RA from all family sets collected from 1996 onwards by the ECRAF. HLA-DRB1 oligotyping from patients and all available nonaffected siblings and parents was carried out. Familial RA was defined by the presence of at least 2 affected first-degree relatives in the same family. The frequencies of HLA-DR NIMA and NIPA were compared using odds ratios after stratification for HLA-DR*04, *0401, and/or *0404 and shared epitope (SE) status. NIMA/NIPA that coincided with inherited parental HLA-DR antigens were considered redundant and were excluded from analysis.

RESULTS

NIMA and NIPA could be analyzed in 165 RA patients with familial RA and 84 nonaffected siblings. Patients were predominantly female, rheumatoid factor positive, and had erosive disease (81, 75, and 84%, respectively). Possession of HLA-DR*04 and *0401/*0404 alleles tended be more frequent in patients than in nonaffected siblings but this did not reach statistical significance. SE possession was similar in patients and healthy siblings, although the former had a double dose SE more often (37.6 vs 17.8%; p = 0.002). Transmission of SE encoding alleles from parents to offspring was skewed only in patients [OR (95% CI) 3.56 (2.55-4.95) vs 1.16 (0.75-1.79) in nonaffected siblings]. Using the NIPA as control, the frequencies of HLA-DRB1*04, *0401/*0404, and SE positive NIMA were not increased in patients lacking these susceptibility alleles. The frequencies of NIMA encoding susceptibility alleles in DR*04 and *0401/*0404 negative patients were lower than in nonaffected siblings.

CONCLUSION

Our results corroborate the association between RA and inherited SE alleles and do not support a role for noninherited HLA-DR maternal antigens in the susceptibility for familial RA.

Association of MICA gene and HLA-B*5101 with Behçet's disease in Greece

PURPOSE

Behçet's disease (BD) is known to be associated with HLA-B51 in many different ethnic groups. Recently MICA, a member of a novel family of the human major histocompatibility complex (MHC) class I genes termed MIC (MHC class I chain-related genes), was identified near the HLA-B gene, and a triplet repeat microsatellite polymorphism was found in the transmembrane (TM) region. Because a strong association with BD of one particular MICA-TM allele, A6, was shown in a Japanese population, the present study was conducted to investigate microsatellite polymorphism in Greek patients with BD to know whether this association is generally observed in BD occurring in other populations.

METHODS

Thirty-eight Greek patients with BD and 40 ethnically matched control subjects were examined for MICA microsatellite polymorphism using polymerase chain reaction (PCR) and subsequent automated fragment detection by fluorescent-based technology.

RESULTS

Similar to the Japanese patients with BD, the phenotype frequency of the MICA-TM A6 allele was significantly increased in the Greek patients with BD (50.0% in control subjects versus 86.8% in BD cases), with an odds ratio (OR) of 6.60 (P = 0.0012). The MICA-A6 allele was found in a high frequency both in males and females (weighted OR = 6.68; P = 0.0017). No association was found between the A6 allele and several disease features. A strong association exists between the MICA-TM A6 allele and the B*5101 allele in both the control subjects and patients with BD (weighted OR = 44.39; P = 0.0000023).

CONCLUSIONS

This study revealed in Greek patients a strong association of BD with a particular MICA-TM allele, MICA-A6, providing insight into the molecular mechanism underlying the development of BD.

HLA-B*5101 in Greek patients with Behçet's disease

Behçet's disease (BD) is a recurrent systemic vasculitis of unknown etiology. Genetic factors and infectious agents seem to be related to the etiology and pathogenesis of the disease. BD is strongly associated with HLA-B51 antigen in many ethnic groups. As there are differences in HLA profile in different ethnic groups, we designed this case-control study to examine the association of HLA-B51 alleles and BD as well as to investigate the influence of sex, age at development of the International Study Group (ISG) for Behçet's Disease criteria and certain features of disease severity on the strength of this association. The study includes 62 Greek BD patients who fulfill the ISG criteria for Behçet's disease and 87 controls. Serological HLA Class-I typing was performed by standard microlymphocytotoxicity technique. HLA-DNA typing for the B5 group was performed in all B51 subjects and controls by PCR-SSO. Allele B*5101 was found in 80% of BD patients and in 26% of controls (odds ratio (OR) 10.48, p < 10[-6]). Males who carry this allele have a higher risk than females for BD (OR 16.97 and 5.74 respectively). B*5101 predisposes to BD at a younger age in both sexes and to the development of erythema nodosum (OR = 11, p = 0.004). This was confirmed by multiple logistic regression analysis. A weak but not significant association was found between B*5101 and uveitis (OR = 2). No association was found between B*5101 and vasculitis or skin lesions in either sex. It was concluded that in the Greek population allele B*5101 is a predisposing marker for BD, as in most ethnic groups, and that this allele predisposes to the development of the disease at a younger age in both sexes and to the development of erythema nodosum.

HLA-DRB1 alleles in Greek rheumatoid arthritis patients and their association with clinical characteristics

The association of certain HLA-DRB1 alleles in Green rheumatoid arthritis (RA) patients with several features of the disease, the gender of the patient and the age at onset was investigated. This case control study includes 86 Greek RA patients and 130 healthy controls unrelated to the patients. HLA typing was performed by polymerase chain reaction (PCR) and hybridization with sequence-specific oligonucleotide (SSO) probes. HLA-DR4 was significantly increased in RA patients. The alleles *0101, *0401, *0405 and *1001 were associated with a higher risk of RA. The *0408 allele was absent from our patients. Sixty-five per cent of RA patients carried the 'sharp epitope' (SE) compared with 31.5% of controls. The risk for RA in individuals carrying a single allele positive for SE was 2.85 times higher, and for those carrying two alleles positive for SE 8.57 times higher, than in SE-negative individuals. The risk was higher in those carrying the *0401 allele, followed by *0405 and *0101, while the genotype *0401/*0404 was absent. Alleles positive for SE comprise a predisposing factor for RA at an early age, particularly in men, and are associated with positive rheumatoid factor, nodules and erosions.

Effects of sho-saiko-to on production of prostaglandin E2 (PGE2), leukotriene B4 (LTB4) and superoxide from peripheral monocytes and polymorphonuclear cells isolated from HIV infected individuals

The effects of Sho-saiko-to (SST), a traditional Chinese medicine, on the production of PGE2 from monocytes, LTB4 and superoxide from polymorphonuclear cells (PMNC) in HIV infected individuals were studied. SST inhibited the production of PGE2 from monocytes stimulated by opsonized zymosan in all groups including the healthy control group and also inhibited the production of superoxide from PMNC after stimulation with FMLP. On the other hand, SST enhanced the production of LTB4 when PMNC were stimulated by the calcium ionophore A23187. These results suggest that SST has different effects on the production of prostanoids or superoxide from monocytes and PMNC. Furthermore, our data indicates that inhibition of PGE2 or superoxide production will lead to indirect suppression of HIV, and enhancement of LTB4 will contribute to the upregulation of the immune reaction in HIV infected individuals.

The immunomodulatory effect of leflunomide in rat cardiac allotransplantation

Leflunomide, a novel immunosuppressant, has been the subject of recent preclinical studies using solid organ allo- and xenotransplantation models. The objectives of this study were to evaluate the efficacy and toxicity of leflunomide using a rat cardiac allotransplant model in two different strain combinations (DA x PVG and DA x Lew). Leflunomide, at doses ranging between 5 and 30 mg/kg, prolonged graft survival in both strain combinations as effectively as CsA and FK506 1 mg/kg (P < 0.05). A dose-dependent effect was seen only after a longer treatment course. When ongoing rejection was intercepted early (postoperative day 2), 5 mg/kg was as effective as 1 mg/kg FK506 (P > 0.05) but was inferior to CsA in the DA x PVG combination (P < 0.05). However, in the DA x Lew combination, leflunomide was equally as efficacious as 15 mg/kg CsA and 1 mg/kg FK506 (P > 0.05). If ongoing rejection was treated at postoperative day 4, 10 mg/kg leflunomide was not only as effective as 15 mg/kg CsA and 1 mg/kg FK506, but demonstrated a dose-dependent increase in graft survival in both strain combinations. The toxicity of leflunomide at doses of especially 5-20 mg/kg was minimal in comparison to therapeutic doses of CsA and FK506 using body weight and biochemical parameters of renal and liver function. These in vivo observations convincingly show leflunomide to be equally as potent an immunosuppressant as CsA and FK506 in transplant rejection. It is also well tolerated on long-term administration and, by virtue of this fact, is a potentially suitable candidate for clinical transplantation.

Active pulmonary tuberculosis in patients with AIDS: spectrum of radiographic findings (including a normal appearance)

PURPOSE

To assess the efficacy of chest radiography in the detection of active pulmonary tuberculosis in patients with acquired immunodeficiency syndrome (AIDS).

MATERIALS AND METHODS

Initial interpretations of chest radiographs of 133 adult patients with AIDS and positive sputum or bronchoalveolar lavage cultures for Mycobacterium tuberculosis were reviewed. Radiographic findings were correlated with CD4 T-cell counts, sputum stains for acid-fast bacilli (AFB), and antituberculous drug sensitivity.

RESULTS

Forty-eight (36%) patients had a primary M tuberculosis pattern, 38 (28%) had a postprimary M tuberculosis pattern, 19 (14%) had normal radiographs, 17 (13%) had atypical infiltrates, seven (5%) had minimal radiographic changes, and four (3%) had a miliary pattern. Normal chest radiographs were seen for 10 (21%) of 48 patients with less than 200 T cells per microliter and one (5%) of 20 patients with more than 200 T cells per microliter. Drug sensitivity and sputum staining for AFB did not correlate with radiographic findings. Overall, 19% of cases had multidrug resistance to antituberculous medications.

CONCLUSION

Chest radiographs did not suggest active tuberculosis in 43 (32%) of 133 AIDS patients with active pulmonary tuberculosis.

HLA class II polymorphism and IDDM susceptibility in the Greek population

The frequencies of HLA-DQA1, DQB1 and DRB1 alleles were compared between 50 Insulin-Dependent Diabetes Melitus (IDDM) patients and 49 healthy controls in the Greek population. Statistically significant difference in the frequencies of HLA-DQA1*0501-DQB1*0201 (P = 10(-4)), DQA1*0301-DQB1*0201 (P = 0.01) and DQA1*0301-DQB1*0302 (P = 0.001) were observed. The DRB1*0405-DQA1*0301-DQB1*0201 was the only DR, DQ combination significantly associated with the disease. The unexpected increase of DRB1*0405 observed in the Greek IDDM may suggest as reported in Chinese and Japanese IDDM a contribution of DR beta and DQ alpha in susceptibility. Moreover, in contrast to the Asians, in the Greek, the DR beta, DQ alpha are found with the usual DQ beta 57-ve.

Fibrocystic disease of the breast and HLA antigens

One hundred and ten patients with fibrocystic disease of the breast and 200 controls were HLA typed with a panel of 100 antisera for A and B locus. The main finding was the decreased frequency of BW35 antigen among patients compared to the controls. The difference remained significant in patients with the fibrous type of the disease and in patients of the nulliparous group. In addition the last group of patients showed a significant increase of All antigen.

Left ventricular function in patients with chronic obstructive pulmonary disease

We assessed the left ventricle function in 24 patients with severe (forced expiratory volume in 1 sec less than 50% of predicted) chronic obstructive pulmonary disease (COPD) and in 21 normal people. We measured the left ventricular systolic time intervals (STI) and echocardiographic left ventricular diameters, volumes, cardiac index, stroke volume index, echo ejection fraction and functional mean rate of circumferential fiber shortening (Vcf). In 13 of the 24 patients with COPD the mean pulmonary artery pressure and pulmonary artery wedge pressure were recorded. The STI in the patients with COPD were found abnormal while the echocardiographic parameters and pulmonary wedge pressure were normal. 1 patient had a high pulmonary arterial wedge pressure and a low Vcf. 2 patients had an ejection fraction less than 60%, but in only 1 of these the Vcf was low. No patient had all three parameters abnormal. We conclude that in patients with COPD the increased right ventricular afterload and the interaction between left and right ventricles are responsible for the abnormal left ventricular STI, while the left ventricular function is normal.

Systolic time intervals in chronic obstructive pulmonary disease

The systolic time intervals (STI) were used to study the left ventricular performance in 51 patients with chronic obstructive pulmonary disease (COPD), in 24 normal subjects and in 13 patients with both COPD and coronary heart disease (CHD). Our study shows that resting spine STI are abnormal in patients with COPD and that the STI in the sitting position and after exercise in these patients are changing in a similar way to those of normal subjects. In patients with both COPD and CHD we found the resting supine STI and the postexercise left ventricular ejection time index (LVETI) to differ from both normals and patients with COPD alone. When these same patients were sitting the STI failed to change, in striking contrast to the normal subjects and to the patients with COPD alone. The similar responses of normal subjects and of patients with COPD in the two stress conditions as well as the different postural and postexercise responses of patients with both COPD and CHD suggest a normal left ventricular function in patients with COPD.

[Frequency of HLA antigens in Greek patients with open-angle glaucoma]

50 Greek patients with primary open-angle glaucoma were tissue-typed for a total of 29 HLA antigens (groups A and B). The results were compared with those of 200 control persons. A statistically significant difference at the level of p less than 0.05 was noted only with regard to the A2 antigen. These findings are in accordance with those of other authors who found no correlation between glaucoma simplex and the frequency of HLA antigens.

The distribution of HLA antigens and genes in the Greek population

200 Greeks were typed by lymphocytotoxicity for 14 HLA-A and 18 HLA-B antigens with 120 sera. A high frequency of Bw35 and B5 antigen was apparent. The most remarkable disequilibria found were those between A2-B5 and A9-B18.

Respiratory drive in patients with chronic obstructive pulmonary disease

Respiratory drive (deltaP 0.1/deltaPCO2) and ventilatory response (deltaVE/deltaPCO2) to CO2 has been estimated in 20 normal subjects and 28 patients with chronic obstructive pulmonary disease (COPD). In patients with COPD, drive and ventilatory response to CO2 were diminished, but no statistical correlation with FEV1, MBC, TLC, FRC, RV/TLC was found. A statistically negative correlation was found between blood bicarbonate and drive or ventilatory response to CO2. Patients with emphysema and normal PaCO2 demonstrated normal deltaP 0.1/deltaPCO2. In contrast, patients with chronic bronchitis with the same pulmonary function abnormalities and hypercapnia had significant diminution of the deltaP 0.1/deltaPCO2. Therefore, we feel that pulmonary function abnormalities alone cannot explain the deltaP 0.1/deltaPCO2 decrease; in most cases there sould coexist a diminished respiratory sensitivity.