T-cell responses in photoimmune therapy

Quo vadis haemapheresis. Current developments in haemapheresis

The techniques of haemapheresis originated in the development of centrifugal devices separating cells from plasma and later on plasma from cells. Subsequently membrane filtration was developed allowing for plasma-cell separation. The unspecificity of therapeutic plasma exchange led to the development of secondary plasma separation technologies being specific, semi-selective or selective such as adsorption, filtration or precipitation. In contrast on-line differential separation of cells is still under development. Whereas erythrocytapheresis, granulocytapheresis, lymphocytapheresis and stem cell apheresis are technically advanced, monocytapheresis may need further improvement. Also, indications such as erythrocytapheresis for the treatment of polycythaemia vera or photopheresis though being clinically effective and of considerable importance for an appropriate disease control are to some extent under debate as being either too costly or without sufficient understanding of the mechanism. Other forms of cell therapy are under development. Rheohaemapheresis as the most advanced technology of extracorporeal haemorheotherapy is a rapidly developing approach contributing to the treatment of microcirculatory diseases and tissue repair. Whereas the control of a considerable number of (auto-) antibody mediated diseases is beyond discussion, the indication of apheresis therapy for immune complex mediated diseases is quite often still under debate. Detoxification for artificial liver support advanced considerably during the last years, whereas conclusions on the efficacy of septicaemia treatment are debatable indeed. LDL-apheresis initiated in 1981 as immune apheresis is well established since 24 years, other semi-selective or unspecific procedures, allowing for the elimination of LDL-cholesterol among other plasma components are also being used. Correspondingly Lp(a) apheresis is available as a specific, highly efficient elimination procedure superior to techniques which also eliminate Lp(a). Quality control systems, more economical technologies as for instance by increasing automation, influencing the over-interpretation of evidence based medicine especially in patients with rare diseases without treatment alternative, more insight into the need of controlled clinical trials or alternatively improved diagnostic procedures are among others tools ways to expand the application of haemapheresis so far applied in cardiology, dermatology, haematology, immunology, nephrology, neurology, ophthalmology, otology, paediatrics, rheumatology, surgery and transfusion medicine.

Psoralen and UVA light: an in vitro investigation of multiple immunological mechanisms underlying the immunosuppression induction in allograft rejection

Photopheresis (ECP) is a novel immunomodulatory therapy effectively used to treat several T-cell-mediated diseases and to reverse allograft rejection after organ transplantation. It consists of infusion of UVA-irradiated autologous leukocytes collected by apheresis and extracorporeally incubated with 8-methoxypsoralen (8-MOP). In this study we explored the potential immunological events for therapeutic efficacy of photopheresis in preventing allograft rejection by evaluating in vitro the combined effects of 8-MOP and UVA (PUVA) on multiple immunological parameters, such as induction of apoptosis, production of soluble mediators, and expression of cell antigens. Peripheral blood mononuclear cells (PBMCs) obtained from healthy subjects were treated with 8-MOP and UVA at the same doses as those clinically used in ECP. We demonstrate that PUVA treatment induced leukocyte hyporesponsiveness and a decrease in expression of co-stimulatory and adhesion molecules as well as of cytokine levels. Additionally, PUVA treatment induced apoptosis in both mononuclear cells (possibly through the Fas/FasL system and/or the CD38 pathway) and purified monocytes. In conclusion, our work focuses attention on the initial phase of immune response and identifies some new targets of therapy (e.g., costimulatory molecules) able to trigger final effects underlying therapeutic efficacy of photopheresis.

Treatment of stage II cutaneous T-cell lymphoma with interferon alfa-2a and extracorporeal photochemotherapy: a prospective controlled trial

BACKGROUND

Both interferon alpha and extracorporeal photochemotherapy have been shown to be effective in primary cutaneous T-cell lymphomas (CTCLs). However, no prospective trial has been published on the combination of both treatments, although retrospective investigations suggested a better efficacy than for either interferon or extracorporeal photochemotherapy.

OBJECTIVE

Our purpose was to evaluate the efficacy and toxicity of combined interferon alfa-2a with extracorporeal photochemotherapy in a prospective controlled trial.

METHODS

A prospective controlled study was performed. Fourteen patients (all male) aged 38 to 72 years with CTCL of the mycosis fungoides type, stage IIa/IIb, and a 72-year-old male patient with a Ki-1 lymphoma were treated twice a month for 6 months with extracorporeal photochemotherapy using oral 8-methoxypsoralen as photosensitizer in combination with interferon alfa-2a subcutaneously 3 times a week in the maximal tolerable dosage (ie, up to 18 x 10(6) U). The effects were investigated by a skin score, staging, histologic score (density of the T-cell infiltrate; from 0 = absent to 3 = heavy), immunohistology, and laboratory investigations including total peripheral T-cell count, CD4/CD8 ratio, and soluble interleukin 2 receptor (sIL-2R).

RESULTS

After 6 months, best response was a complete response (CR) in 4 patients, a partial response (PR) in 3, and a stable disease (SD) in 7 of 14 patients (overall response rate [CR + PR] 50%). In responders the time to best response was 4.3 +/- 1.4 months. The skin score decreased from 22.5 +/- 8.1 to 15.1 +/- 11.0 (P <.001), the histologic score decreased from 2.57 +/- 0.51 to 1.21 +/- 0.80 (P <.001). In the lesional skin the percentage of CD4 cells decreased from 75% to 51% (P =.038) and Ki-67-positive cells decreased from 6.7% to 2.4% (P =.001). The total T-cell count/microL decreased from 1018.9 +/- 557.1 to 667.9 +/- 417.9 (P =.012), and the CD4/CD8 ratio also decreased from 1.88 +/- 0.92 to 1.51 +/- 0.67 (P =.038). The sIL-2R levels did not change significantly during the first 4 months of treatment. Among patients of stage IIa the response rate was 60% in contrast to only 25% of those in stage IIb. Side effects were seen temporarily, ranging from grade 0 to grade 3. There was no need for additional therapy, but interferon dose was decreased because of side effects. After 1 year of follow-up the total response rate was 46.2% (6 of 13 patients): 5 of 9 with stage IIa(55.6%) and 1 of 4 with stage IIb (25.0%).

CONCLUSION

These results indicate that patients with CTCL stage IIa can achieve a total response rate of 56% with combined interferon alfa-2a and extracorporeal photochemotherapy. Responders seem to experience their best response within the first 6 months of treatment. The treatment is well tolerated and does not cause severe side effects.

Intralesional autotherapy of cutaneous leishmaniasis with buffy coat cells: cytological findings

The skin lesions of five patient volunteers with dry-type cutaneous leishmaniasis were treated by intralesional injection of auto-leukocytes prepared from buffy coat of the patient's own blood. Giemsa stained, air-dried cytological smear preparations were prepared from scrapings taken from the margins of the lesions. The cellular interaction between the organism and the inflammatory response of the host was studied. All lesions showed clinical evidence of regression. The cytological findings suggested progressive degradation of the Leishman donovan (LD) bodies within the parasitophorous vacuoles of the activated macrophages. The parasiticidal effect appeared to be induced by synergistic action of the injected neutrophils and lymphocytes. Due to lack of placebo controls in this study the possibility that, healing might not be related to therapy can not be excluded. This study illustrates the potential for intralesional autotherapy with buffy coat in dry-type cutaneous leishmaniasis.