Marrow donor immunity to herpes simplex virus: association with acute graft-versus-host disease.

The interactions between humoral and cellular immunity to herpes simplex virus (HSV) in bone marrow donors, the occurrence of active HSV infections, and the development of grades II-IV acute graft-versus-host disease (GVHD) in their HLA-A,B,C,DR-identical sibling recipients were studied. The absence of IgG-class HSV antibodies in the marrow donors was associated with a low incidence of GVHD: 38 of 53 recipients (72%) of marrow from HSV-seropositive donors developed GVHD versus only two of 15 recipients (13%) with HSV-seronegative donors (p = 0.0004). The cellular immunity to HSV was studied in vitro by evaluating the degree of lymphocyte proliferative responses to that virus and was also significantly associated with GVHD: 30 of 43 recipients (70%) of marrow from donors with a positive test developed GVHD versus 10 of 25 recipients (40%) of marrow from donors with a negative test (p = 0.03). The previously reported risk for GVHD attributed to donor CMV antibodies increased the risk of GVHD due to donor HSV antibodies. Of 31 recipients of marrow from donors who were both HSV- and CMV-seropositive, 27 (85%) developed GVHD versus 11 of 22 recipients (50%) of marrow from HSV-seropositive but CMV-seronegative donors (p = 0.008).

The influence of T cell depletion on recovery of T cell proliferation to herpesviruses and Candida after allogeneic bone marrow transplantation.

To test the influence of T cell depletion of the marrow in allogeneic bone marrow transplantation on functional T cell recovery, in vitro lymphocyte proliferation tests (LPTs) to microbial antigens were regularly performed in 23 recipients of normal BM and in 25 patients receiving BM with a fixed low number of T cells (1 x 10(5) T cells/kg body weight; recipients of T-depleted BM). The long-term recovery of positive LPT to at least 1 of the 4 tested microbial antigens--Candida, herpes simplex virus (HSV), varicella-zoster virus (VZV), and cytomegalovirus--was nearly similar in both groups: 16/23 versus 18/25. Recovery of LPT to Candida and HSV in the first 3 months appeared to be greatly influenced by prophylactic measures; only 2/23 recipients of normal BM, receiving amphotericin B, showed a positive LPT to Candida versus 13/25 recipients of T-depleted BM (P less than 0.01). In contrast, only 1/23 seropositive recipients of T-depleted BM, receiving acyclovir, showed a positive LPT to HSV versus 9/22 recipients of normal BM (P less than 0.05). A positive LPT to CMV in the first 3 months was found in 9/9 seropositive recipients of normal BM, versus in 5/11 seropositive recipients of T-depleted BM (P less than 0.05). Five of the 6 patients with a negative LPT died of CMV-interstitial pneumonia versus 1/14 with positive LPT (P less than 0.01). We conclude that in CMV-seropositive recipients of allogeneic BM, T cell depletion of the graft affects the early recovery of T cell proliferation to CMV, which is associated with a higher risk of fatal CMV-interstitial pneumonia.

Cellular immunity to vaccinations and herpesvirus infections after bone marrow transplantation.

The cellular immune response to herpesviruses was studied in 46 recipients of marrow grafts (23 autologous, 23 allogeneic). That study was performed in vitro by evaluating the degree of lymphocyte proliferative responses to herpes simplex virus (HSV), cytomegalovirus (CMV), and varicella zoster virus (VZV). No primary infections with any of those viruses were noted after bone marrow transplantation (BMT). The incidence of active infection in seropositive patients was significantly lower after autologous BMT than after allogeneic BMT (HSV, 2/22 vs. 11/22 patients, respectively, P = 0.007; CMV, 4/12 vs. 9/10 patients, respectively, P = 0.02; VZV, 3/23 vs. 11/23 patients, respectively, P = 0.02). After autologous BMT, the restoration of cellular immunity to the three viruses occurred at a clearly faster rate than after allogeneic BMT. That pattern may have contributed to the low incidence of active infections with those viruses after autologous BMT. Recipients of allogeneic marrow from donors with a positive lymphocyte proliferation test to HSV had a significantly increased incidence of active HSV infection post-BMT (8/9 patients) than those who received marrow from donors with a negative test (3/13 patients; P = 0.008). Acute or chronic graft-versus-host disease (GVHD) decreased the cellular immune response to the three herpes viruses, but not significantly. Our program of vaccinations with diphtheria and tetanus toxoids started in the fourth month post BMT. Chronic GVHD patients who were vaccinated had a clearly impaired cellular immune response to both toxoids as compared with those without chronic GVHD.

Acquired secretion defect in platelets after cryopreservation in dimethyl sulfoxide.

Despite the use of preservatives, platelets are severely damaged during cryopreservation and, following freezing, function poorly in a number of in vitro tests. We report here that cryopreserved platelets show diminished aggregation in response to collagen. This may be a consequence of a secretion defect as evidenced by a 20 to 30 percent loss of dense- and alpha-granule content (p less than 0.05) and an impaired secretion mechanism. Analysis of adenine nucleotides confirmed the defect in dense granule adenosine triphosphate (ATP) and adenosine diphosphate (ADP) content (storage pool), but in addition revealed a 50 percent fall in cytosolic ATP (metabolic pool). In contrast, the adenylate energy charge, (ATP + 1/2 ADP)/(ATP + ADP + adenosine monophosphate), was normal. We concluded that platelet cryopreservation leads to a secretion defect, probably as a result of activation during freezing and thawing procedures.

Differences in the susceptibility of platelets to freezing damage in relation to size.

Previous studies have shown that cryopreservation of normal platelets induces a reduction in the contents of secretion granules, the generation of thromboxane B2, and aggregability. The present study investigates whether these changes in the total population occur to the same extent in four size-dependent subpopulations with mean platelet volumes of 4.2, 5.7, 8.0, and 11.1 microns 3, obtained by counterflow centrifugation. Cryopreservation reduced the contents of the alpha granule markers and the generation of thromboxane B2 in the platelets from the four fractions to the same extent as in the platelets from the total suspension. Maximal aggregation of the platelets in response to collagen was measured by optical aggregation. The average decrease in light transmission after freezing was 47 +/- 3 percent (SEM) for the platelets in the total population, 40 +/- 3 percent for the largest platelets, and 65 +/- 5 percent for the smallest platelets, which indicates that aggregability was better preserved in the larger platelets than in the smaller cells. It is possible that, in the smallest platelets, a decrease in thromboxane generation of approximately 70 percent becomes rate-limiting for aggregation. Further improvements in the clinical use of freeze-preserved platelets may be sought in the preparation of concentrates with relatively high counts of large platelets.

Serology versus PCR-SSP in typing for HLA-DR and HLA-DQ: a practical evaluation.

In this study, serological HLA-DR and -DQ typing results were compared to typing results obtained with sequence-specific primers in the polymerase chain reaction (PCR-SSP). HLA-DR typing was performed on a random caucasian population consisting of 31 patients and 73 healthy individuals. Considering HLA-DR1-10, differences in typing results were found in 3 out of 73 healthy individuals and 8 out of 31 patients. When HLA-DR1-16 alleles were taken into account, differences in typing results were found in 11 out of 31 patients and 14 out of 73 healthy individuals. Typing results of PCR-SSP, different from that of serology, were all confirmed by sequencing-based typing of HLA-DRB1 alleles. HLA-DQ1-3 typings were performed on 40 individuals consisting of 17 patients and 23 healthy individuals. Differences in typing results were found in 5 out of 17 patients and 1 out of 23 healthy individuals. From the results of this study it can be concluded that serology is a reliable technique, when restricted to identification of HLA-DR1-10 and HLA-DQ1-3 antigens in healthy individuals. By PCR-SSP, however, reliable HLA-DR1-16 and -DQ1-3 typings can be obtained both in patients and healthy individuals.