Systemic antitumor protection by vascular-targeted photodynamic therapy involves cellular and humoral immunity - PubMed (original) (raw)

Systemic antitumor protection by vascular-targeted photodynamic therapy involves cellular and humoral immunity

Dina Preise et al. Cancer Immunol Immunother. 2009 Jan.

Abstract

Vascular-targeted photodynamic therapy (VTP) takes advantage of intravascular excitation of a photosensitizer (PS) to produce cytotoxic reactive oxygen species (ROS). These ROS are potent mediators of vascular damage inducing rapid local thrombus formation, vascular occlusion, and tissue hypoxia. This light-controlled process is used for the eradication of solid tumors with Pd-bacteriochlorophyll derivatives (Bchl) as PS. Unlike classical photodynamic therapy (PDT), cancer cells are not the primary target for VTP but instead are destroyed by treatment-induced oxygen deprivation. VTP initiates acute local inflammation inside the illuminated area accompanied by massive tumor tissue death. Consequently, in the present study, we addressed the possibility of immune response induction by the treatment that may be considered as an integral part of the mechanism of VTP-mediated tumor eradication. The effect of VTP on the host immune system was investigated using WST11, which is now in phase II clinical trials for age-related macular degeneration and intended to be evaluated for cancer therapy. We found that a functional immune system is essential for successful VTP. Long-lasting systemic antitumor immunity was induced by VTP involving both cellular and humoral components. The antitumor effect was cross-protective against mismatched tumors, suggesting VTP-mediated production of overlapping tumor antigens, possibly from endothelial origin. Based on our findings we suggest that local VTP might be utilized in combination with other anticancer therapies (e.g., immunotherapy) for the enhancement of host antitumor immunity in the treatment of both local and disseminated disease.

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Figures

Fig. 1

Fig. 1

Effect of host immune system on WST11–VTP efficacy_._ Three mouse strains with normal (BALB/c; squares, n = 11), T-cell deficient (BALB/nude; triangles, n = 16) or T- and B-cell deficient (NOD/scid; circles, n = 18) immune system and bearing CT26 s.c. tumors were subjected to WST11–VTP and monitored for tumor response (*P < 0.004 by student’s t test)

Fig. 2

Fig. 2

WST11–VTP induced systemic anti-tumor protection_._ BALB/c mice bearing s.c CT26 tumors were subjected to VTP and challenged i.v. with viable CT26 cells. Lungs were excised 2 weeks after challenge and weighed. a Lung micrographs and respective histological images, b homologous protection 2 weeks, c three months after VTP, d cross-protection 2 weeks and e three months after VTP. Positive control-naïve age-matched mice i.v. injected with CT26 cells. Representatives of 2–3 experiments are shown (*P < 0.008 by student’s t test)

Fig. 3

Fig. 3

Neutrophil infiltration into the s.c. CT26 tumors following WST11–VTP_._ Formaldehyde fixed tumors were stained for specific naphthol AS-D chloroacetate esterase activity. Analysis was done using Image Pro Plus software. Neutrophils are stained in purple. Three mice were used for each time point. One representative experiment is shown. Each bar represents percent of area covered by neutrophils of 4–6 sequential fields taken from one slide normalized to total tumor area (mean ± SE, n = 3)

Fig. 4

Fig. 4

CD3+ lymphocytes infiltration into the CT26 s.c. tumors following WST11–VTP_._ Tumors were excised at various times after the treatment, fixed in Bouin’s fixative and paraffin-embedded. Slices were stained with α-mouse CD3+ antibodies. CD3+ lymphocytes are stained in brown; a untreated tumor, b 1 h after VTP, c magnification of the square from b, d 24 h after VTP, e 48 h after VTP and f magnification of the square from e. T tumor, BV blood vessel, N necrotic area; arrows denote CD3+ cells. Each bar represents percent of area covered by CD3+ of 4–6 sequential fields taken from one section normalized to total tumor area (mean ± SE, n = 3)

Fig. 5

Fig. 5

Cellular immune responses induced by WST11–VTP; a adhesion of VTP-sensitized or naïve splenocytes to cultured tumor cells. Splenocytes were stained with DiI or Di-Asp vital dyes and incubated with untreated or photodynamically pre-treated cultured CT26 or 4T1 cells. Adhesion was assessed by fluorescent microscope. Ten images were acquired for each group using appropriate filter sets and area covered by splenocytes was calculated (P < 0.005), b VTP-induced splenocyte cytotoxicity. Splenocytes were incubated with cultured CT26 cells. Specific cytotoxicity was measured by LDH release according to formula: % specific lysis = (experimental release − spontaneous release)/(maximum release − spontaneous release) × 100. Experiments were performed in triplicates, c IFNγ secretion by splenic T-cells isolated from naïve or cured mice upon in vitro re-stimulation with VTP-treated CT26 cells, d CD8+ cells adoptive transfer (P < 0.03), e CD4+ cells adoptive transfer (P < 0.005). Cells were isolated from naïve or cured mice and i.v. injected to lymphodepleted naïve recipients that were subsequently challenged i.v. with 2 × 105 live CT26 cells and lung metastases development was assessed by lung weighing 2 weeks after challenge. Control mice were injected with PBS; representatives of 2–3 experiments are shown and f verification of lymphodepletion in BALB/c mice. Depletion was tested in peripheral blood of the mice irradiated with 300 Rad a week earlier. Blood was collected in the presence of anticoagulant, cells separated by gradient centrifugation and stained for flow cytometry analysis

Fig. 6

Fig. 6

Humoral responses induced by WST11–VTP; a sera from naïve mice or mice 1 or 2 weeks after CT26 tumor VTP was blotted against homogenates of untreated CT26 tumor or tumor isolated 24 h after VTP: a new Abs formed after VTP; b new or hidden Ag exposed by VTP; c Ag that disappeared after treatment; b CD45R+ cell infiltration into the CT26 s.c. tumors. Positive cells are stained in brown. T tumor, BV blood vessel, arrows denote CD45R+ cells (_n_= 3); c serum IgG binding to cultured CT26 cells. Serum was obtained from naïve mice and mice-bearing CT26 s.c. tumors before and 1 week after VTP and applied on cultured CT26 cells. Binding was detected with HRP-conjugated anti-mouse IgG antibodies (n = 3) and d serum transfer; serum from naïve and cured mice was injected i.v. (500 μl/mouse) to naïve mice that were subsequently challenged with 2 × 105 live CT26 cells and lung metastases development was assessed by lung weighing 2 weeks after challenge. A representative of two experiments is shown (P < 0.001)

Fig. 7

Fig. 7

Effect of DCs depletion on WST11–VTP_._ DTR bone marrow chimera mice bearing CT26 s.c. tumors were depleted from DCs and subjected to WST11–VTP; a effect of systemic DTx injection on splenic DC population, b local DC depletion was initiated by peri-tumoral DTx injection 24 h before VTP and maintained by daily injections for 14 days (P < 0.04), c systemic DC depletion was initiated by i.p. DTx injection 48 h before VTP and maintained every 2 days by injection for 14 days (P < 0.004). Group received VTP only (squares, n = 17), group received VTP with depletion (triangles, local n = 28; systemic _n_=11), group received DTx only (circles, local n = 6; systemic n = 5)

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References

    1. Adam JK, Odhav B, Bhoola KD. Immune responses in cancer. Pharmacol Ther. 2003;99:113–132. doi: 10.1016/S0163-7258(03)00056-1. - DOI - PubMed
    1. Agaiby AD, Dyson M. Immuno-inflammatory cell dynamics during cutaneous wound healing. J Anat. 1999;195(Pt 4):531–542. doi: 10.1046/j.1469-7580.1999.19540531.x. - DOI - PMC - PubMed
    1. Banchereau J, Briere F, Caux C, Davoust J, Lebecque S, Liu YJ, Pulendran B, Palucka K. Immunobiology of dendritic cells. Annu Rev Immunol. 2000;18:767–811. doi: 10.1146/annurev.immunol.18.1.767. - DOI - PubMed
    1. Boumedine RS, Roy DC. Elimination of alloreactive T cells using photodynamic therapy. Cytotherapy. 2005;7:134–143. doi: 10.1080/14653240510027109. - DOI - PubMed
    1. Butterfield LH, Ribas A, Dissette VB, Amarnani SN, Vu HT, Oseguera D, Wang HJ, Elashoff RM, McBride WH, Mukherji B, Cochran AJ, Glaspy JA, Economou JS. Determinant spreading associated with clinical response in dendritic cell-based immunotherapy for malignant melanoma. Clin Cancer Res. 2003;9:998–1008. - PubMed

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