Identification of human antitumor cytotoxic T lymphocytes epitopes of recoverin, a cancer-associated retinopathy antigen, possibly related with a better prognosis in a paraneoplastic syndrome.

Cancer-associated retinopathy (CAR) is a rare paraneoplastic syndrome, and the recoverin-specific autoantibody is suggested to contribute to the pathogenesis of retinopathy, including apoptosis of retinal cells. Because it is known that CAR(+) cancer patients have a preferable prognosis, we hypothesized that aberrantly expressed recoverin in cancer cells can become a target of cytotoxic T lymphocytes (CTL). Here we tested nine recoverin-derived HLA-A24-binding peptides for their capacity to elicit antitumor CTL. We observed recoverin-specific CTL responses in two HLA-A24(+) CAR(+) cancer patients. In addition, the CTL responses were obtained from three of ten CAR(-) cancer patients and two of six healthy individuals. The CTL precursor frequency of CAR(+) cancer patients and that of CAR(-) cancer patients was higher than that of healthy individuals. Of nine recoverin peptides, R49 (QFQSIYAKF), R49.2 (QFQSIYAKFF), and R64 (AYAQHVFRSF) were discovered to induce the peptide-specific CTL. Taken together, our present data suggest that peripheral activation of recoverin-specific antitumor CTL is likely to contribute to the preferable prognosis of CAR(+) cancer patients. Moreover, in cases other than CAR(+) cancer patients, recoverin may offer the opportunity to design epitope-based immunotherapeutic approaches for treating HLA-A24(+) cancer patients with a recoverin-expressing tumor.

Human CD8 and CD4 T cell epitopes of epithelial cancer antigens.

Recent human tumor immunology research has identified several genes coding immunogenic peptides recognized by CD8 cytotoxic T lymphocytes (CTLs) in melanoma tumors. Very recently, CD4 T cell antigenic epitopes were also determined in certain melanoma tumors. The use of these peptides in conjunction with human immunotherapy could prove to be of great benefit. However, such peptides in clinically common tumors of epithelial cell origin, such as of the stomach, colon, lung, etc., have not yet been determined extensively. We describe for the first time an HLA-A31 (A*31012)-restricted natural antigenic peptide recognized by the CD8 CTL TcHST-2 of gastric signet ring cell carcinoma cell line HST-2. We also identified the HLA-DRB1*08032-restricted peptide recognized by the CD4 T cell line TcOSC-20 of squamous cell carcinoma OSC-20 derived from the oral cavity. The antigenic peptide of HST-2, designated F4.2, is composed of 10 amino acid residues with two anchor motif residues necessary for binding to HLA-A31 molecules. The synthetic F4.2 peptide enhanced the reactivity of TcHST-2 against HST-2 cells. Furthermore, introduction of an expression minigene coding F4.2 peptide to HLA-A31(+) cells conferred cytotoxic susceptibility to TcHST-2 on the cells. Some stomach cancer lines into which the HLA-A31 gene had been introduced, such as MKN28-A31-2, were lysed by TcHST-2, suggesting the presence of F4.2 peptide in at least some HLA-A31(+) stomach cancers. Furthermore, F4.2 peptide induced an F4.2 peptide-specific CTL response in at least 30-40% of HLA-A31(+) peripheral blood lymphocytes from gastric cancer patients, suggesting that F4.2 peptide could be used as a cancer vaccine for gastric tumors. The natural antigenic peptide of OSC-20 was also determined using acid extraction and biochemical separation and by mass spectrometry. Consequently, OSC-20 peptide was designated as the 6-1-5 peptide, an HLA-DRB1*08032-restricted 16-mer peptide with two possible anchor motifs. It has an amino acid sequence identical to that of human alpha-enolase, suggesting that it was derived from the processed parental alpha-enolase protein. We are presently attempting to determine the genes that code tumor rejection antigens recognized by HLA-A24- and A26-restricted T cells, including those of pulmonary and pancreatic carcinomas. The search for these antigenic peptides may lead to the identification of immunogenic peptide antigens that would be suitable for clinical use in commonly occurring epithelial cancers.

Induction of cytotoxic T lymphocytes from peripheral blood of human histocompatibility antigen (HLA)-A31(+) gastric cancer patients by in vitro stimulation with antigenic peptide of signet ring cell carcinoma.

Antigenic peptides have been used as a cancer vaccine in melanoma patients and have led to a drastic regression of metastatic tumors. However, few antigens have been identified in non-melanoma tumors. We recently purified a new natural antigenic peptide, designated F4. 2, by biochemical elution from a human gastric signet cell carcinoma cell line and showed that it is recognized by an autologous human histocompatibility antigen (HLA)-A31-restricted cytotoxic T lymphocyte (CTL) clone. Here we describe in vitro induction of F4. 2-specific CTLs from peripheral blood T lymphocytes of HLA-A31( +) gastric cancer patients. The T cells of seven HLA-A31( +) patients with gastric cancers were stimulated in vitro by F4.2-pulsed autologous dendritic cells which had been induced from peripheral blood of each patient by incubation in the presence of granulocyte macrophage colony-stimulating factor (GM-CSF) and IL-4. We tested the cytotoxicity of the T cells against F4.2-loaded C1R-A*31012 by a 6-h (51)Cr release assay after 3 stimulations with F4.2-pulsed dendritic cells. F4.2-specific cytotoxicity was detectable in the stimulated T cells from two of the seven HLA-A31( +) patients. Further, both F4.2-specific CTLs also lysed the gastric cancer cell line, HST-2, from which F4.2 was derived. These results suggest that F4.2 peptide may be useful as an HLA-A31-restricted peptide vaccine in certain patients with gastric cancer.

Identification of natural antigenic peptides of a human gastric signet ring cell carcinoma recognized by HLA-A31-restricted cytotoxic T lymphocytes.

Peptides of human melanomas recognized by CD8+ CTLs have been identified, but the nature of those of nonmelanoma tumors remains to be elucidated. Previously, we established a gastric signet ring cell carcinoma HST-2 and HLA-A31 (A*31012)-restricted autologous CTL clone, TcHST-2. In the present study, we determined the natural antigenic peptides of HST-2 cells. The purified preparation of acid-extracted Ags was submitted to the peptide sequencer, and one peptide, designated F4.2 (Tyr-Ser-Trp-Met-Asp-Ile-Ser-Cys-Trp-Ile), appeared to be immunogenic. To confirm the antigenicity of F4.2 further, we constructed an expression minigene vector (pF4.2ss) coding adenovirus E3, a 19-kDa protein signal sequence plus F4.2. An introduction of pF4.2ss minigene to HST-2 and HLA-A31(+) allogeneic tumor cells clearly enhanced and induced the TcHST-2 reactivity, respectively. Furthermore, when synthetic peptides of F4.2 C-terminal-deleted peptides were pulsed to HST-2 cells, F4.2-9 (nonamers), but not F4.2-8 or F4.2-7 (octamer or heptamer, respectively), enhanced the reactivity of TcHST-2, suggesting that the N-terminal ninth Trp might be a T cell epitope. This was confirmed by lack of antigenicity when using synthetic substituted peptides as well as minigenes coding F4.2 variant peptides with Ala or Arg at the ninth position of F4.2. Meanwhile, it was indicated that the sixth position Ile was critically important for the binding to HLA-A31 molecules. Thus, our data indicate that F4.2 may work as an HLA-A31-restricted natural antigenic peptide recognized by CTLs.

Early active motion and weightbearing after cross-stitch achilles tendon repair.

Twenty-two closed Achilles tendon ruptures caused by sports injuries in 22 patients (average age, 37.6 years) were repaired with Kirschmayer core suture and cross-stitch epitenon suture, and early active ankle motion with weightbearing was implemented after surgery. This study was undertaken to evaluate the effectiveness of the repair technique and rehabilitation protocol by assessing clinical results and magnetic resonance imaging findings. The follow-up period averaged 24.6 months. Twenty of the tendons (91%) healed without rerupture, and two tendons (9%) suffered a partial rerupture at 23 and 56 days, respectively. Active ankle extension reached from the minus range to 0 degree in an average of 9.7 days, and ankle motion recovered to normal in an average of 6.0 weeks. Full weightbearing without heel raising became possible in an average of 16.4 days, and heel raising with both legs became possible in an average of 7.3 weeks. The patients returned to full sports activity in 13.1 weeks. The interval until the area of high-intensity signal at the tendon repair site on T2-weighted magnetic resonance imaging scans became intermediate-intensity signal averaged 6.9 weeks, and the tendon repair site became low-intensity signal in an average of 12.6 weeks, demonstrating excellent tendon healing. Treatment employing Kirschmayer core suture and cross-stitch epitenon suture may help athletes return to sports activity in a shorter period than that allowed by previous methods of repair for Achilles tendon ruptures.

Recurrent dorsal angulation of the distal radius fracture during dynamic external fixation.

Thirty-three fractures of the distal radius treated with a dynamic external fixator (that allowed for wrist motion between 2 to 4 weeks after surgery) were analyzed, focusing on loss of fracture reduction during external fixation. Fractures with preoperative dorsal angulation greater than 20 degrees and those involving the distal radioulnar joint had a significantly larger loss of reduction of dorsal angulation (8.9 degrees and 6.9 degrees, respectively) than fractures with less severe preoperative dorsal angulation or those with an intact distal radioulnar joint (3.0 degrees and 2.6 degrees, respectively). In contrast, preoperative radial shortening (>2 mm) and involvement of the radiocarpal joint did not significantly increase the loss of dorsal angulation. Neither of the 2 dynamic external fixation systems studied consistently stabilized Colles' fractures with preoperative dorsal angulation of greater than 20 degrees or involvement of the distal radioulnar joint.

Cutting-out of the lag screw after internal fixation with the Asiatic gamma nail.

Sixty consecutive intertrochanteric femoral fractures were treated with the Asiatic gamma nail followed by early postoperative weight bearing. Cutting-out of the lag screw from the femoral head occurred in six fractures and were analysed radiographically with regard to fracture type (Evans' classification), osteoporosis (Singh grade), accuracy of post-operative reduction (neck-shaft angle and diastasis of the fracture), and location of the lag screw in the femoral head (depth, height, and antero-postero-posterior radiograph and large antero-posterior deviation of the lag screw were significantly related to the increased incidence of the screw cutting-out. This suggests that deep insertion of the lag screw on the antero-posterior view with central placement on the lateral view is an optimal location in the femoral head. The ¿cut-out index' (the multiplication value of the depth and the anteroposterior deviation of the lag screw in the femoral head) is an excellent measure of the risk of the lag screw cutting-out.

Recent trend on the prevalence of tardive dyskinesia in Japan.

An epidemiological study was undertaken, taking a survey of 2,274 chronic schizophrenic patients hospitalized for 2 years or more in 17 mental institutions in Japan. The overall prevalence of tardive dyskinesia (T.D.) was 19.1%. The prevalence of TD differs considerably from one institution to the other, with a range of 0 to 36.1%. The longer the history of institution was, the higher the prevalence of TD. The prevalence showed a tendency to increase with increasing age. Long-term hospitalization concomitant with continuous neuroleptic medication seemed to play a role in the prevalence of TD. TD occurred with higher frequency in patients with somatic complications than in those without complications. Past drug history, including duration of treatment and responsible neuroleptics, has been considered to play an important role in the prevalence of TD. But, results of the present investigation showed that the present drug status might also influence on the appearance of TD. The facts obtained from the present study are of value to establish regimens mainly based on medical treatment for prediction and prevention of TD.