Soluble HLA in human body fluids

There is a growing body of information about the soluble forms of HLA in serum but there are only a few reports discussing sHLA in other body fluids. We quantitated sHLA-I and sHLA-II concentrations in sweat, saliva and tear samples from five normal individuals with known HLA-phenotypes. We also studied sweat samples from an additional 12 normal nonphenotyped subjects, as well as in CSF of 20 subjects with different illnesses, using solid phase enzyme linked immunoassay. Sweat, saliva and tears from normal subjects were found to contain very low or nondetectable amounts of sHLA-I. In contrast, sHLA-II molecules were found in each of these body fluids, although, with considerable variation between individuals. The presence of sHLA-II in saliva was further confirmed by Western-blotting. It was observed that sHLA-II having molecular mass of 43,900 and 18,100 daltons was comparable with that found in serum from normal individuals. In addition, no association of sHLA-II levels with allospecificities in either body fluid or in serum was apparent. The results of CSF sHLA concentrations in different diseases were as follows: (1) High CSF SHLA-I levels were measured during viral encephylitis (n = 3), while none of these patients contained sHLA-II in CSF; (2) The levels of sHLA-II, but not sHLA-I were elevated in CSF of patients during seizure (n = 6) and of patients with neonatal hepatitis (1 of 2) or with connective tissue disease accompanied with viral infection (n = 2); (3) No CSF sHLA-I or sHLA-II could be detected at polyneuropathy (n = 2), or in patients with syphilis (n = 3), or leukemia (n = 2) with evidence of neurologic involvement of central nervous system. Taken together, it may be concluded that the presence of sHLA in several body fluids is physiologically normal. It appears that sHLA-II is the predominant class of HLA molecules present in different body fluids. We propose that the system responsible for sHLA-II production in various body fluids must involve different mechanisms than those responsible for sHLA-I synthesis in serum.

Tumor-associated antigens are cytokine inducers and hyporeactivity factors to the immune system

We investigated possible mechanisms leading to the inhibition of the immune system in people with chronic disorders. Tumor cell produce protein released into the circulation, such as tumor associated antigens, may play an important role in processes preceding paralysis of the immune system. To test this hypothesis the following tumor associated antigens were used: AFP, OFP, CA-125, CA-50 and CA-19-9. Their role was assessed by modulating cytokine production in cord blood lymphocytes and peripheral white blood cells obtained from grown population of patients treated with colostrinin, an cytokine inducer. PHA, LPS and colostrinin were used as positive control in those essays. Each antigen tested individually induced IFN, TNF alpha and IL-6 in dose dependent fashion. None of the tested cytokines were spontaneously released by the cells. Data generated from these experiments indicated that tumor associated antigens are inducing type 1 cytokines in similar fashion as LPS or colostrinin. However, lymphocytes taken from patients undergoing therapy with colostrinin revealed progressive loss capability to produce type 1 cytokines as they did in case of colostrinin. The loss of the capability to respond to antigen may represent phenomenon leading to immune tolerance.

Soluble HLA class I antigens in patients with type I diabetes and their family members

Our objective was to study a possible contribution of MHC genes to S-HLA-I secretion in patients with Type I diabetes. Quantitatively, we used a highly sensitive enzyme-linked immunoassay to measure S-HLA-I in the serum of a total of 39 patients with Type I diabetes, as well as 36 kinships of 12 diabetic patients and 82 normal individuals with known HLA-phenotypes. S-HLA-I levels were abnormally elevated in patients or their non-diabetic relatives compared to normal controls (p < 0.0009). No complete HLA-haplotype had been identified to be correlated with high or low S-HLA-I secretion. Only the HLA-A23 or A24 (splits of HLA-A9) positive individuals sera were found to contain high S-HLA-I concentrations in all populations studied. The difference in S-HLA-I levels of HLA-A24 patients (n = 4) or their HLA-A24 positive non-diabetic relatives (n = 10) to the group of HLA-A24 normal controls (n = 15) was statistically highly significant (p < 0.0005 and p < 0.0009, respectively). The results suggests that HLA-A24 may confer additional independent risk for the disease expression in male children but not in female siblings. Nevertheless, the data implies that the patients or their non-diabetic relatives carrying the HLA-A24 have increased risk of developing ICA associated with high S-HLA-I levels compared to HLA-A24 negative probands or their kinships with low levels of S-HLA-I. This effect occurred irrespective to other diabetes related HLA-DR alleles. In summary, the results show a pronounced genetic heterogeneity of Type I diabetes with MHC control of the expression of S-HLA-I and possible involvement of hormonal factors that might potentiate a specific synthesis of S-HLA-I. The findings have implications for identifying individuals with a possible risk for developing the disease.

Soluble HLA antigens and ELISA--a new technology for crossmatch testing

A soluble HLA ELISA for the detection of donor specific anti-HLA class I IgG antibodies was developed and compared with microlymphocytotoxicity. Donor sHLA was prepared from donor blood or purified blood lymphocytes and captured onto monoclonal antibody coated ELISA plates. After incubation of captured HLA with test serum, bound IgG antibodies were detected using a peroxidase-conjugated anti-human IgG antibody. Serum samples from patients on waiting lists to receive kidney transplants were tested by lymphocytotoxicity (AHG protocol) and/or sHLA ELISA in four different laboratories using HLA preparations from eight organ donors. Concordant crossmatch results were obtained for 854 (99%) of 864 ELISA crossmatches. In contrast, concordant results were obtained for 234 (91%) of 256 lymphocytotoxicity crossmatches. Interlaboratory reproducibility of ELISA results was 99%. In contrast, interlaboratory reproducibility of lymphocytotoxicity assay results was 78%. Endpoint titrations of serum specimens containing anti-HLA antibodies demonstrated equivalent sensitivity of ELISA and AHG lymphocytotoxicity crossmatch and similar sensitivity of ELISA and flow cytometry crossmatch. Specimens tested positive by lymphocytotoxicity without DTT treatment but negative with DTT treatment were tested negative by ELISA. Comparison of lymphocytotoxicity and ELISA crossmatch results showed an agreement of 94%. This demonstrates that detection of anti-donor HLA class I antibodies by ELISA is a reliable alternative to microlymphocytotoxicity testing.

Soluble HLA antigens and ELISA--a new technology for crossmatch testing

A soluble HLA ELISA for the detection of donor specific anti-HLA class I IgG antibodies was developed and compared with microlymphocytotoxicity. Donor sHLA was prepared from donor blood or purified blood lymphocytes and captured onto monoclonal antibody coated ELISA plates. After incubation of captured HLA with test serum, bound IgG antibodies were detected using a peroxidase-conjugated anti-human IgG antibody. Serum samples from patients on waiting lists to receive kidney transplants were tested by lymphocytotoxicity (AHG protocol) and/or sHLA ELISA in four different laboratories using HLA preparations from eight organ donors. Concordant crossmatch results were obtained for 854 (99%) of 864 ELISA crossmatches. In contrast, concordant results were obtained for 234 (91%) of 256 lymphocytotoxicity crossmatches. Interlaboratory reproducibility of ELISA results was 99%. In contrast, interlaboratory reproducibility of lymphocytotoxicity assay results was 78%. Endpoint titrations of serum specimens containing anti-HLA antibodies demonstrated equivalent sensitivity of ELISA and AHG lymphocytotoxicity crossmatch and similar sensitivity of ELISA and flow cytometry crossmatch. Specimens tested positive by lymphocytotoxicity without DTT treatment but negative with DTT treatment were tested negative by ELISA. Comparison of lymphocytotoxicity and ELISA crossmatch results showed an agreement of 94%. This demonstrates that detection of anti-donor HLA class I antibodies by ELISA is a reliable alternative to microlymphocytotoxicity testing.

Detection of panel-reactive anti-HLA class I antibodies by enzyme-linked immunosorbent assay or lymphocytotoxicity. Results of a blinded, controlled multicenter study

A soluble HLA ELISA for the detection of anti-HLA class I IgG antibodies was developed and compared to complement-dependent microlymphocytotoxicity. ELISA plates were coated with a panel of sHLA class I antigens isolated from the culture supernatants of 46 different EBV-transformed phenotyped B-cell lines. After the incubation of the coated plates with test serum, bound antibodies were detected using a peroxidase-conjugated anti-human IgG antibody. Absorbance was read using an ELISA plate reader and assay results were analyzed by computer. Antibody specificities were determined by Fisher's exact test tail analysis. The reproducibility of ELISA assay results was evaluated in a blinded, controlled multicenter study. A total of 102 serum specimens from patients on waiting lists to receive kidney transplants were tested five times by ELISA in five different laboratories. The correlation coefficients (r) of %PRA values determined by ELISA ranged from 0.89 to 0.96, and the average agreement on qualitative assay results (antibody positive vs antibody negative) was 98%. Endpoint titration of several serum specimens demonstrated equivalent sensitivity of ELISA and microlymphocytotoxicity (using the anti-globulin antibody protocol). Most of the antibody specificities determined by ELISA were in agreement with specificities determined by microlymphocytotoxicity. To evaluate the correlation of ELISA and microlymphocytotoxicity (CDC) assay results the same 102 specimens were tested six times by CDC in five different laboratories. The interlaboratory correlation coefficient (r) of %PRA values determined by microlymphocytotoxicity ranged from 0.57 to 0.94, and the average agreement on qualitative assay results was 85%. A comparison of ELISA with microlymphocytotoxicity was performed using consensus microlymphocytotoxicity results. This showed a high correlation (r = 0.81) of %PRA values determined by ELISA and microlymphocytotoxicity. This demonstrates that the detection of anti-HLA class I antibodies by soluble HLA ELISA is a reliable alternative to microlymphocytotoxicity testing.

The proto-oncogene/translation factor eIF4E: a survey of its expression in breast carcinomas

The eukaryotic translation initiation factor eIF-4E binds to the cap structure of mRNAs as one component of the eIF-4 translation initiation complex, which mediates the recruitment of mRNA to the ribosomes. Overexpression of eIF-4E can result in oncogenic transformation and uncontrolled growth of mammalian cells, presumably by facilitating the expression of growth-control gene products which are normally translationally repressed. Whereas the mechanism of eIF-4E-mediated transformation is being actively pursued, clinical investigations into the expression of eIF-4E in prevalent human cancers are lacking. We have recently initiated a screen of breast carcinomas by probing with eIF-4E antiserum. Using Western blots, we have analyzed the level of eIF-4E in 38 carcinomas, 7 normal samples and 3 fibroadenomas. We found that eIF-4E was elevated 3- to 10-fold in virtually all the carcinomas we analyzed, but not in fibroadenomas. This analysis was also confirmed by immunohistological staining in situ, showing that overexpression of eIF-4E can be readily identified at the single-cell level. Our results suggest that an elevation of eIF-4E may be an essential component in the development of breast cancer.

Arranging hospital admission for acutely ill patients: problems encountered by general practitioners

BACKGROUND

Reports in the national press suggest that general practitioners in London are experiencing difficulties in securing hospital admission for their acutely ill patients.

AIM

A study was undertaken to investigate the problems encountered by general practitioners in one family health services authority in south east London in arranging acute admissions to hospital.

METHOD

A self-report questionnaire was completed by a sample of general practitioners every time an acute hospital admission was attempted.

RESULTS

A total of 493 questionnaires were completed by 111 general practitioners over the 47-day study period. Problems during the hospital admission procedure were experienced in 171 (35%) of the cases reported, with 115 of the 537 telephone calls to a hospital (21%) resulting in a refusal to admit the patient to that particular hospital. The main problem reported was that of 'no beds available', an obstacle to admission that was more likely to be encountered if the patient was aged 75 years or over than if the patient was younger.

CONCLUSION

In the light of the problems reported, possible changes to the current method of arranging acute admissions to hospital in London are discussed.

Hormonal receptors in locally advanced breast cancer: change with response to neoadjuvant chemotherapy?

Twenty-one cancers in 20 patients with locally advanced breast cancer were studied. Incisional biopsy was performed without using electrocautery. Tissue was obtained for histology and estrogen (ER) and progesterone (PR) receptors. Patients received chemotherapy after biopsy. All responded and had radical mastectomy performed. Tissue was removed from the mastectomy specimen to confirm residual tumor and for repeat receptor measurements. Initial receptor levels were negative in 13 cancers. Following chemotherapy, both ER and PR levels were unchanged in 11 cancers. Levels in one cancer changed from ER-PR- to ER+PR- and one changed from ER-PR- to ER+PR+. Six cancers were ER+PR+ at initial examination. Repeat receptor levels after chemotherapy were ER+PR+ in three. One ER+PR+ tumor became ER-PR+, one changed to ER+PR-, and one to ER-PR-. One ER+PR- cancer remained ER+PR- after treatment and an ER-PR+ cancer became ER-PR- after treatment. Chemotherapy dose not significantly alter hormonal levels in breast cancer tissue.

The role of plasma fibronectin as a nonantibody, noncomplement opsonin for Staphylococcus aureus

The possible role of plasma fibronectin as a nonantibody, noncomplement opsonin for S. aureus was studied using peripheral blood leukocytes from healthy rabbits. Fibronectin depletion of normal rabbit serum by affinity absorption chromatography reduced the opsonic ability of that serum (p less than 0.05) and resulted in impaired bacterial killing of S. aureus in vitro. The addition of purified fibronectin to fibronectin-depleted serum significantly reversed the opsonic defect (p less than 0.01). The combination of complement inactivation, plus fibronectin depletion, resulted in a severe opsonic deficiency that was much worse than either deficiency alone (p less than 0.05). However, fibronectin alone in the absence of other serum factors was a poor opsonin for S. aureus, suggesting that its major role as an opsonin might be to augment or amplify other serum factors.

Sequential prospective analysis of the nonspecific host defense system after thermal injury

The nonspecific host defense system of 66 patients with thermal injuries was studied prospectively. Our goal was to correlate the magnitude of injury with changes in host defenses and to determine if the responses of patients with and without sepsis were different. Eighteen patients experienced one or more septic episodes. Synchronous serial measurements of circulating fibronectin levels, neutrophil locomotive activity and phagocytosis, and intracellular killing in all patients showed that multiple components of the nonspecific host defense system were impaired after thermal injury. The depression of random migration and chemotaxis and the magnitude of the initial depression in serum fibronectin levels were related to the severity of injury but did not predict sepsis. Only a decrease in neutrophil bactericidal activity or a secondary depression in the serum fibronectin level was associated with the onset of sepsis.

Prognostic significance of abnormal neutrophil chemotaxis after thermal injury

Neutrophil chemotaxis was studied sequentially in 23 thermally injured patients and 23 normal volunteers. The average age of the burn victims was 48 years (range, 21-87) and mean total body surface area burned was 33% with a mean full-thickness component of 16%. Chemotaxis was measured under agarose since this test system allowed the chemotactic generating ability of the patients' serum to be evaluated as well as the chemotactic capability of the neutrophils. In excess of 800 determinations were performed on the burned patient population. Eighty-three per cent of the patient population had a decrease in chemotaxis two standard deviations below normal at some time during the hospital stay, in most patients three or more days postburn. This chemotactic defect appeared to be unrelated to the presence of a chemotactic factor inactivator. There was no statistically significant correlation between the development of abnormal chemotaxis and sepsis or mortality in this patient population.

Biologic effect of blister fluid from thermal injuries on peripheral neutrophil chemotaxis

Patients who become immunologically incompetent after major thermal injury often show in vitro defects in neutrophil function, including abnormalities of neutrophil chemotaxis. Although there is evidence suggesting that this acquired chemotactic defect is related to circulating suppressor substance(s) in the serum of these individuals, neither the etiology of this chemotactic defect nor the origin of these putative suppressors have been clarified. We report studies directed toward determining the biologic effect of blister fluid from thermally injured patients on peripheral neutrophil chemotaxis. Fifteen blister fluid samples from 12 patients were tested in attraction and inhibition assays of neutrophil chemotaxis. Chemotaxins were observed in all specimens. The biologic activity of blister fluid was similar to that produced by complement in serum and presumably was due to complement activity in the blister fluid. No inhibitors of chemotaxis were found in the blister fluid samples, although it seemed logical to expect to find suppressors in this fluid if they were generated locally by the thermal injury. Since suppressors were not found locally, other explanations must be sought to explain the etiology of the acquired defect in neutrophil chemotaxis that occurs after thermal trauma.

Prospective evaluation of some candidate tumor markers in the diagnosis of pancreatic cancer

As part of a prospective diagnostic protocol, patients suspected of having pancreatic cancer had systemic and portal venous blood samples assayed, in coded batches, for peptide hormones and enzymes thought to be of potential value as tumor markers. An average of 111 patients were tested for each candidate marker. Results were analyzed by dividing patients into three groups according to the definitive diagnoses. These were pancreatic cancer (32% of patients), other cancers (27%), and benign diseases (41%). Although elevated mean levels of fasting plasma glucose and serum alkaline phosphatase were found in the pancreatic cancer group, there were no significant differences in the mean levels of any of the candidate markers studied in the three groups. The diagnostic values of normal and elevated levels of each candidate marker studied have been calculated. None has proven to be as useful as the serum level of pancreatic oncofetal antigen, fasting plasma glucose, or serum alkaline phosphatase in the diagnosis or exclusion of pancreatic cancer.

Studies on an oncofetal antigen, POA

This paper describes the purification and partial characteristics of a putative oncofetal antigen, POA, which appears to be associated with the pancreas. POA is a glycoprotein of molecular weight between 800,000 and 900,000 daltons. It is found in fetal pancreas and pancreas cancer tissue, but not in normal adult pancreas. It is clearly different from carcinoembryonic antigen, other known tumor associated antigens, acute phase reactants and normal serum proteins. A quantitative rocket immunoelectrophoresis assay was developed for POA. Its specificity was monitored routinely by double immunodiffusion against known fetal and adult standards. The assay was performed on sera from over 700 patients. The results demonstrate that POA is found in the sera of most individuals. However, by far the highest absolute levels and the highest frequency of elevated levels was found in sera of patients with carcinoma of the pancreas. Elevated levels of POA were also found in the serum of a proportion of patients with carcinomas of the lung, stomach, colon, biliary tract, and breast and in a few other individuals with benign conditions. The spectrum of patients who have elevated levels of POA in their serum is quite different from that found with CEA or other known tumor markers.

The leukemic phase of histiocytic lymphoma. Histologic, cytologic, cytochemical, ultrastructural, immunologic and cytogenetic observations in a case

A case of histiocytic lymphoma that progressed to a leukemic phase was studied by various methods. Although the cells were found to bear a superficial morphologic resemblance to histiocytes, they more closely resembled transformed lymphocytes. Immunologic markers strongly supported a B-lymphoid origin in this case, while cytogenetic analysis indicated a large number of consistent chromosomal rearrangements, including a translocation involving chromosomes Nos. 8 and 14 which has been previously reported to occur primarily in Burkitt's lymphoma.