Results of switchback from ranibizumab to aflibercept in patients with exudative age-related macular degeneration.

PURPOSE: Intravitreal injection of anti-VEGF drugs has become standard therapy for patients with exudative age-related macular degeneration (AMD). However, some patients do not exhibit sufficient response to the drugs for suppression of choroidal neovascularization activity. We investigated the efficacy of switchback from ranibizumab to aflibercept in patients with AMD who could not achieve further benefit beyond initial therapy of aflibercept injection. METHODS: Eleven eyes of eleven patients were included in this study. Two patients were nonresponders, and nine exhibited tachyphylaxis to aflibercept. All patients received three monthly injections of ranibizumab as an initial phase of switching and received aflibercept as a switchback drug. We investigated changes in injection interval, visual acuity, and central retinal thickness. RESULTS: In four patients (36.4%), injection interval was extended. The interval was 6.73 weeks before switch and 9.27 weeks after switchback (P=0.96). LogMAR visual acuity was 0.22 before switch and 0.24 after switchback (P=0.62). Central retinal thickness was 306.8 µm before switch and 256.1 after switchback (P=0.13). In all patients who were nonresponders to aflibercept, injection interval could not be extended. CONCLUSION: A switchback from ranibizumab to aflibercept may be beneficial in some patients with AMD who exhibit tachyphylaxis to aflibercept.

Three-year results of a modified photodynamic therapy procedure (Ironing PDT) for age-related macular degeneration patients with large lesions.

BACKGROUND: To evaluate the effect of photodynamic therapy (PDT) using a modified procedure on exudative age-related macular degeneration having been conventionally difficult to treat. METHODS: The medical records of eight consecutive patients (eight eyes) with age-related macular degeneration treated with modified PDT were reviewed retrospectively. Modified PDT was used for the lesions that could not be covered by conventional use of PDT, either because the lesion was too large or too close to the optic disc. A moving PDT laser spot at constant speed, for 83 seconds, was used to cover the entire lesion, and was named "Ironing PDT." This retrospective study was performed with informed patient consent. It was approved by the Institutional Review Board of Kansai Medical University. RESULTS: No exudation could be found 36 months after treatment in five eyes (62.5%). There was no significant difference between the best-corrected visual acuity before PDT (0.95 logMAR) and after PDT (1.09 logMAR). The logMAR best-corrected visual acuity was improved in one eye, maintained in five eyes, and deteriorated in two eyes. CONCLUSION: Ironing PDT decreased subfoveal fluid and preserved visual acuity in some patients with age-related macular degeneration difficult to treat with conventional therapy.

Initial non-responders to ranibizumab in the treatment of age-related macular degeneration (AMD).

BACKGROUND: Patients with exudative age-related macular degeneration (AMD) who did not respond to ranibizumab at the induction phase were assessed and referred to as initial non-responders. METHODS: We retrospectively reviewed the medical records of 215 patients (218 eyes) with exudative AMD. For the initial treatments, patients received three intravitreal injections of ranibizumab (IVR) every 4 weeks. Minimum follow-up period was 12 months. We defined patients with no improvement of best corrected logMAR visual acuity (BCVA), and with no decrease of central retinal thickness (CRT) at the end of the initial treatment, as initial non-responders. Patients who had previous treatment history prior to this investigation were included, but patients who had photodynamic therapy (PDT) with IVR were excluded. RESULTS: Twenty-two eyes (10.1%) were identified as initial non-responders. The mean BCVA of initial non-responders before IVR and after induction phase were 0.39 and 0.36, respectively. There was no significant difference between these values, however the mean BCVA decreased significantly to 0.55 at 12 months after the beginning of the induction phase (P = 0.021). The mean greatest linear dimension (GLD) of the lesion before IVR of initial non-responders was 4,121 µm. We found 16 eyes with typical AMD, and six eyes with polypoidal choroidal vasculopathy. One eye had predominantly classic choroidal neovascularization (CNV), and others had occult CNV of typical AMD. As additional treatments, twelve eyes received PDT, and in three of the eyes exudation remained after PDT. CONCLUSION: Initial non-responders were more prevalent in patients with occult CNV than in patients with other CNV types. Some of the initial non-responders did not respond to PDT. This study suggested possible involvement of other factors, in addition to vascular endothelial growth factor, in the occurrence of CNV in initial non-responder patients.

Human herpesvirus 6-associated uveitis with optic neuritis diagnosed by multiplex PCR.

PURPOSE: Human herpesvirus 6 (HHV-6), which is usually responsible for exanthem subitum in children, can be reactivated from its latent state. We report a case of unilateral optic disc edema and retinal vasculitis associated with HHV-6 infection. CASE: A healthy 63-year-old man noted a decrease in the vision of his left eye. On examination, his left eye had moderate mutton-fat keratic precipitates, vitreous opacities, significant optic disc edema surrounded by yellowish-white swelling in the inner retina, retinal arteritis, and cotton-wool-like exudates. He was started on corticosteroid therapy and aspirin. After 1 month, the disc edema was reduced, the cotton wool-like exudates had decreased, and his visual acuity had improved to 10/20 OS. Multiplex polymerase chain reaction (PCR) of an aqueous humor sample revealed the presence of genomic DNA of HHV-6 but not of the other HHVs. CONCLUSIONS: The HHVs are known to infect the ocular tissues, but the differential diagnostic signs of HHV-6 are still not well known. We recommend that multiplex PCR of the aqueous humor be performed to search for the genomic DNA of HHV-6 in suspected cases of herpesviral infection.

Initial in vitro investigation of the human immune response to corneal cells from genetically engineered pigs.

PURPOSE: To compare the in vitro human humoral and cellular immune responses to wild-type (WT) pig corneal endothelial cells (pCECs) with those to pig aortic endothelial cells (pAECs). These responses were further compared with CECs from genetically engineered pigs (α1,3-galactosyltransferase gene-knockout [GTKO] pigs and pigs expressing a human complement-regulatory protein [CD46]) and human donors. METHODS: The expression of Galα1,3Gal (Gal), swine leukocyte antigen (SLA) class I and class II on pCECs and pAECs, with or without activation by porcine IFN-γ, was tested by flow cytometry. Pooled human serum was used to measure IgM/IgG binding to and complement-dependent cytotoxicity (CDC) to cells from WT, GTKO, and GTKO/CD46 pigs. The human CD4(+) T-cell response to cells from WT, GTKO, GTKO/CD46 pigs and human was tested by mixed lymphocyte reaction (MLR). RESULTS: There was a lower level of expression of the Gal antigen and of SLA class I and II on the WT pCECs than on the WT pAECs, resulting in less antibody binding and reduced human CD4(+) T-cell proliferation. However, lysis of the WT pCECs was equivalent to that of the pAECs, suggesting more susceptibility to injury. There were significantly weaker humoral and cellular responses to the pCECs from GTKO/CD46 pigs compared with the WT pCECs, although the cellular response to the GTKO/CD46 pCECs was greater than to the human CECs. CONCLUSIONS: These data provide the first report of in vitro investigations of CECs from genetically engineered pigs and suggest that pig corneas may provide an acceptable alternative to human corneas for clinical transplantation.

Signaling from fibroblast growth factor receptor 2 in immature hematopoietic cells facilitates donor hematopoiesis after intra-bone marrow-bone marrow transplantation.

Fibroblast growth factor (FGF) and FGF receptor (FGFR) are expressed in various cells including endothelial progenitor cells and hematopoietic cells. The interaction between FGF and FGFR is associated with the proliferation, migration, and survival of these cells. In this report, we examined the effects of FGFR2 signaling on hematopoiesis in immature hematopoietic cells, using mutant mice in which a constitutively active form of FGFR2 mutant was caused to be overexpressed by the Tie2 promoter (FGFR2 Tg mice). Under normal conditions, hematopoiesis of FGFR2 Tg mice and wild type (Wt) mice do not differ significantly, except for the weight and cell numbers of the thymus. However, the c-kit(+)Sca-1(+)lineage⁻ bone marrow cells (BMCs) of FGFR2 Tg mice facilitate the formation of colony-forming units of culture. When these BMCs were transplanted into the recipient bone marrow (intra-bone marrow-bone marrow transplantation), there was better reconstitution of donor hematopoietic cells. In the in vitro experiment, the c-kit(+)Sca-1(+)lineage⁻ BMCs from FGFR2 Tg mice showed fewer apoptotic cells than those from Wt mice. These results suggest that the antiapoptotic effect of FGFR2 signaling facilitates the hematopoiesis of FGFR2 Tg mice.

Abnormal distribution of dendritic cells in (NZW x BXSB)F1 mice.

(NZW x BXSB)F1 mice (W/BF1 mice) have been reported to develop autoimmune diseases with aging. We have also reported that the number of dendritic cells (DCs) increases in the various organs, and that the B-cell response to LPS or interleukin-4 plus anti-mu increase with aging in W/BF1 mice. In the present experiment, we show that many DCs exist not only in the T-cell area but also in the B-cell area and the sinus in the spleen of aged W/BF1 mice, and that the coculturing of DCs from aged W/BF1 mice and B cells from disease-free young W/BF1 mice produces much more IgG and IgM than normal mice. These results suggest that an abnormal distribution of DCs and the interaction of DCs and B cells induce the hyperproduction of immunoglobulin in aged W/BF1 mice.

Genetically engineered pig red blood cells for clinical transfusion: initial in vitro studies.

BACKGROUND: Pigs are a potential source of red blood cells (RBCs) and could resolve the shortage of human blood for transfusion. This study investigated in vitro the compatibility of genetically engineered pig RBCs (pRBCs) with the human innate immune response. STUDY DESIGN AND METHODS: Human volunteers of all ABO blood types were sources of sera and those of O blood type were sources of circulating monocytes/macrophages. RBCs from ABO-compatible (ABO-C) and ABO-incompatible (ABO-I) humans and wild-type (WT) and alpha-1,3-galactosyltransferase gene-knockout (GTKO) pigs were tested for hemagglutination, immunoglobulin (Ig)M/IgG antibody binding, and complement-dependent cytotoxicity (CDC) using human sera. Phagocytosis of RBCs by human monocyte-derived macrophages was measured by coculture in the absence or presence of pooled human O serum. RESULTS: RBCs showed significant differences (p < 0.01) with regard to hemagglutination, IgM and IgG binding, and CDC (ABO-C < GTKO < ABO-I < WT). In the absence of pooled human O serum (antibodies), there was no phagocytosis of any RBCs; in the presence of serum (antibodies), phagocytosis of ABO-I RBCs was greater than of WT (p < 0.01), which in turn was greater than of GTKO RBCs (p < 0.05). CONCLUSIONS: GTKO RBCs were significantly more compatible than ABO-I and WT RBCs, but were not comparable to ABO-C combinations. In the presence of antibody, human monocyte-derived macrophages phagocytosed ABO-I RBC/sera combinations more efficiently than pRBCs. These observations contribute to our ultimate goal of using genetically engineered pRBCs for clinical blood transfusion. However, pigs will require other modifications or manipulations if they are to become suitable for human transfusion.

Extensive studies on perfusion method plus intra-bone marrow-bone marrow transplantation using cynomolgus monkeys.

The collection of bone marrow cells (BMCs) using a perfusion method has been advantageous not only because of the low contamination of BMCs with T cells from the peripheral blood but also the enrichment of stromal cells, which support hemopoiesis. Before the application of this new method to humans, its safety needed to be confirmed using cynomolgus monkeys. We therefore performed the perfusion method on more than 100 cynomolgus monkeys using the long bones (such as the humerus and femur) and also the iliac bones (for human application); in the more than 150 trials to date, there have been no accidental deaths. Furthermore, the technical safety of a new method for the intra-bone marrow (IBM) injection of BMCs (termed IBM-bone marrow transplantation) has also been confirmed using 30 monkeys. Disclosure of potential conflicts of interest is found at the end of this article.