Tissue distribution of the Pk antigen as determined by a monoclonal antibody

Using an anti-Pk monoclonal antibody (mAb) designated CPK-1, the expression of the Pk antigen was assessed on normal human tissue from non-Pk individuals. Although the Pk antigen was detected on fibroblasts and blood vessels as previously reported, it was also found on smooth muscle cells of the digestive tract and the urogenital system. Pk was also found on glandular cells of the stomach, oesophagus and prostate. Additionally, CPK-1 reacted weakly with oesophagus squamous cells, and a small number of glomeruli and tubules in the kidney. The mechanism of expression of the Pk determinant in non-Pk individuals is discussed.     

Longmire Lecture: My 50 Years at the University of California, Los Angeles

The main concept driving my work has been the humoral theory of immunity to allografts. It led to the development of the microlymphocytotoxicity test, which is used to look for the relevant transplant antigens using alloantisera. Using alloantibodies produced by pregnancies, the HLA system was defined through a series of international histocompatibility workshops. It was then shown that the HLA system was important for matching donors and recipients for bone marrow transplants and organ transplants. More than 6000 HLA-matched kidney transplants from cadaver donors have now been shared in the United States. HLA antigens were found to be of importance in anthropologic and disease susceptibility studies. Currently HLA antibodies are being studied intensively to determine their role in chronic rejection. If it is proven that these antibodies trigger intimal proliferation, occluding arterioles, HLA antibodies will become essential to the monitoring of chronic rejection.     

Morphological change in the MNNG-treated rat gastric mucosa

To investigate the process of carcinogenesis in gastric cancer, we studied the histological features of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-treated rats. Samples of the gastric mucosa from both MNNG-treated and control rats were histologically examined every 2 months, for 10 months. In 40% of the MNNG-treated rats, atrophy in the gastric mucosa was observed after 2 months, and regenerative epithelium was observed after 4 months, followed by adenomatous proliferation and disappearance of the tight junction electron microscopically after 6 months. A small intestinal cancer had developed in 2 rats at 6 months. While gastric cancer had developed in 3 rats at 8 months, and in one of these 3 rats, peritoneal dissemination was observed macroscopically and histologically. These results suggested that adenomatous proliferation and disappearance of the tight junction observed electron microscopically were characteristic pathological features of precancerous lesions in the stomach in MNNG-treated rat.     

Primary gastric lymphoma: a clinicopathological study

A retrospective study of 25 patients treated for primary gastric lymphoma was made to investigate a number of problems related to treatments and report the factors influencing prognosis. In the 5-year-survival rate according to Working Formulation classification, either survival rate of low-grade type or intermediate-grade type was higher than that of high-grade type. Both the 5-year-survival rate of cases without lymph node metastasis and that of cases that involved perigastric lymph nodes were higher than that of cases that involved distant gastric lymph nodes. Those surviving five years after perigastric lymph node metastasis had received D3 or D4 dissection and postoperative multicombined chemotherapy. Tumors invading only to the submucosal layer had received D2 dissection and were not treated by postoperative multicombined chemotherapy, and recurrence was not recognized in these cases. Of 9 cases infiltrating into the musclaris propria or serosa without lymph node metastasis, 8 cases were treated by postoperative multicombined chemotherapy and were alive without recurrence, but one case without postoperative multicombined chemotherapy died by recurrence. Therefore, adequate therapy for gastric lymphoma with infiltrating into submucosal layer is gastrectomy with D2 lymph node dissection, and postoperative multicombined chemotherapy is not necessary. The cases with perigastric lymph node metastasis, or the cases with invading from muscularis propria to serosa require D3 or D4 lymph node dissection with postoperative multicombined chemotherapy. But the cases with distant gastric lymph node metastasis or invading adjacent structure or high-grade type histologically (WF classification) require preoperative chemotherapy.     

抗体介导的排斥反应与临床

随着器官移植体液免疫理论的发展与抗体检测技术的进步,抗体介导的排斥反应(AMR)已逐渐被认识和引起关注。其治疗难度大、逆转率较低,已成为导致移植物失功的重要原因。本文较为系统地介绍了AMR的免疫机制、诊断与防治进展,以及供者特异性抗体的检测技术和临床意义,从而提出供者特异性抗体是引起移植物排斥反应特别是慢性排斥反应的主要原因,移植受者需常规监测抗体以利及时干预和治疗。     

Extremely High Association Between Appearance of HLA Antibodies and Failure of Kidney Grafts in a Five-Year Longitudinal Study

Longitudinal studies were conducted over a five-year period for HLA antibodies on 493 sera tested from 54 kidney transplant patients. HLA single antigen beads were employed to establish donor specificity of the antibodies. Only 3 of 22 patients without antibodies rejected a graft in contrast to 17 out of 32 patients with posttransplant antibodies (p = 0.003). Using a serum creatinine value of 4.0 mg/dL as the cut-off for a failed graft, 4 of 22 patients without antibodies failed compared to 21 of 32 with antibodies (p = 0.0006). Among patients with donor-specific antibodies (DSA) 13 of 15 failed (p = 0.000004). Even among patients with non-donor specific antibodies (NDSA), 8 of 17 failed (p = 0.05). Among patients who could be identified as making de novo antibodies (since they developed antibodies while not having antibodies for more than six months after transplantation), 6 of 11 failed (p = 0.03). Sequential testing for HLA antibodies shows that antibodies appear prior to a rise in serum creatinine and subsequent graft failure. The very strong association between the production of HLA antibodies after transplantation and graft failure indicates the importance of monitoring for posttransplant HLA antibodies.     

Paired kidney donation by shipment of living donor kidneys

It is apparent from calculations that for paired kidney donation programs, a national program will provide optimum benefit. To obviate major problems associated with donors traveling long distances, we propose shipping donor kidneys. Evidence is provided from the United Network for Organ Sharing (UNOS) Kidney Transplant Registry, that 14,873 immediate functioning kidneys from deceased head-trauma donors with an average cold ischemia time of 18.3 h had 85.7% three-yr graft survival compared with 87.8% survival of 23 369 transplants from living donors with 2.4 h of ischemia. Grafts from 10,368 deceased donors with 13-24 h cold ischemia time had three-yr graft survival of 82.6% compared with 84.2% for 1153 transplants with up to six h cold ischemia time. After adjusting for major confounding factors, cold ischemia does not significantly influence graft survival. We conclude that shipment of donor kidneys can be performed safely and will significantly increase paired donor transplants.     

Evidence that intracellular magnesium is present in cells at a regulatory concentration for protein synthesis.

When extracellular magnesium is reduced by a factor of 50 (from 1.0 to 0.02 mM), the total intracellular magnesium of a spontaneously transformed clone of 3T3 cells decreases by 30-50%. Protein synthesis rates in these cells were measured as the intracellular magnesium decreased. Protein synthesis rates and magnesium content were found to decrease in parallel with each other. At 3 hr, a decrease to 84% of control values of magnesium content was accompanied by a decrease to 85% of control values of leucine incorporation rates. A larger inhibition had occurred by 12 hr, when the magnesium had decreased to 67% and leucine incorporation rates had decreased to 57%. When magnesium was restored to magnesium-deprived cells, both magnesium content and leucine incorporation increased about 2-fold by 1 hr. In the experiments reported here, initial small changes in magnesium content are associated with changes in protein synthesis rates. This strongly suggests that magnesium is present at a regulatory rather than excess concentration for protein synthesis. The results are consistent with a role for intracellular magnesium in the regulation of protein synthesis and support the hypothesis that magnesium has a central role in the regulation of metabolism and growth.     

Proposed Diagnostic Criteria for Chronic Antibody‐Mediated Rejection in Liver Allografts

Donor‐specific alloantibodies (DSA) can cause acute antibody‐mediated rejection (AMR) in all solid organ allografts. However, long‐term outcome in patients with posttransplant DSA needs further study. We retrospectively evaluated prospectively collected paired serum, tissue, and data on 45 matched DSA? positive [DSA+; mean florescence intensity (MFI) ≥10 000] and ‐negative (DSA?) recipients of a primary liver‐only allograft from January 2000 to April 2009. Blinded histopathologic evaluation demonstrated that DSA+ versus DSA? patients were more likely to have subtle inflammation and unique patterns of fibrosis, despite normal or near‐normal liver function tests. Stepwise multivariable modeling developed a score (putatively named the chronic AMR [cAMR] score) that included interface activity, lobular inflammation, portal tract collagenization, portal venopathy, sinusoidal fibrosis, and hepatitis C virus status. The score was developed (c = 0.811) and cross‐validated (c = 0.704) to predict allograft failure. Two cutoffs were employed to optimize sensitivity and specificity (80% each); a value >27.5 predicted 50% 10‐year allograft failure. We propose chronic AMR as a potential new entity defined by (1) a high cAMR score, (2) DSA, and (3) elimination of other potential causes of a similar injury pattern. In conclusion, cAMR score calculation identified liver allograft recipients with DSA at highest risk for allograft loss, although independent validation is needed.