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S J Lauer

Publications and source records attributed to S J Lauer.

62 records · Page 4Linked to original sources
PubMed1983

Evaluation of cerebrospinal fluid mononuclear cells obtained from children with acute lymphocytic leukemia: advantages of combining cytomorphology and terminal deoxynucleotidyl transferase.

Sixty cerebrospinal fluid (CSF) samples were obtained from 28 children with terminal deoxynucleotidyl transferase (TdT) positive acute lymphocytic leukemia (ALL). Cell morphology was evaluated using Wright's stained cytocentrifugation prepared slides. The presence of nuclear TdT was detected by an immunofluorescent (IF) assay. Evaluation of CSF mononuclear cells using these two methods simultaneously allowed us to differentiate between leukemic and nonleukemic pleocytosis. Agreement between cytomorphology and TdT in identifying CNS lymphoblasts was found in 55 of 60 samples. Seventy-two per cent of the TdT-positive samples were obtained from children with CSF cell counts less than 10 WBC/mm3. We recommend that these two methods be used in conjunction when evaluating CSF mononuclear cells from children with TdT positive ALL.

Child↗
PubMed1983

In vitro enhancement of peripheral blood mononuclear cell natural killer activity following short term incubation with fetal calf serum.

This study demonstrates that short term incubation of blood mononuclear cells (MC) in heterologous sera enhances their natural killer (NK) but not their antibody dependent killer (K) activity, and confirms that NK stimulation is not related to blastogenesis. MC were obtained from healthy donors and incubated with RPMI 1640 supplemented with various serum sources. NK and K activity of incubated vs. fresh MC against SK-N-SH, Chang or Raji cell line targets were compared in a 4-hr 51Cr release assay. A significant (p less 0.01) increase in NK cytotoxicity was detected when MC were incubated with fetal calf serum (FCS) or human AB serum (ABS) at 37 degrees C. When a more sensitive NK target cell (K-562) was used only the cells incubated in FCS demonstrated increased NK cytotoxicity. Augmentation of NK cell activity by FCS was not related to blastogenesis, mitosis, natural antibodies against lymphocytes or target cells, immunoglobulin complexes or alterations in MC OKT4 and OKT8 subpopulations. In contrast to NK activity, K cytotoxicity was not increased after incubation at 37 degrees C in FCS or ABS, and it was depressed in IPT (p less than 0.05). Thus FCS is capable of stimulating NK cell activity against human tumor cell lines in less in less than 24 hr.

Animals↗
PubMed1982

Association between HLA-D region antigens and disease-free survival in childhood non-T, non-B acute lymphocytic leukemia.

The frequency of three serologically defined HLA-D region antigens--DR, MB, and MT--was determined in a group of 74 children with non-T, non-B acute lymphocytic leukemia (ALL). Statistically, there were no significant differences in the frequency of any antigen in these ALL patients as compared with a panel of 85 normal controls. However, significant differences in HLA-DR frequencies were observed between patients who relapsed or who remained disease-free during a 30-mo period of chemotherapy. An increased incidence of relapse was associated with DR5, while disease-free remission during chemotherapy was associated with DR7. Life table analysis also demonstrated that DR5 was significantly associated with a decrease in disease-free survival in these patients. These data suggest that HLA-associated genetic factors may influence the responses of ALL patients to chemotherapy.

Adolescent↗
PubMed1979

Shifts in expression of cell membrane phenotypes in childhood lymphoid malignancies at relapse.

To determine if cell membrane phenotypes change under the selective pressures of therapy we have conducted a prospective study of 54 children with lymphoid malignancies of T-like, B-like, common, and null cell types. Membrane phenotypes were determined at diagnosis in all patients and again 1-24 mo later in 18 children who either failed induction therapy or had one or more relapses. In 7 patients the cells tested were from relapse sites different than those of the original diagnoses. The data indicate that at relapse most children with lymphoid neoplasias had the same cell membrane phenotype as established at diagnosis, and suggest that the site of relapse did not affect the expression of cell surface markers. However, there were three exceptions: (1) a child initially diagnosed as having null cell acute lymphocytic leukemia had 90% T-antigen-positive blasts in her second-relapse bone marrow; (2) only membrane IgM was present on relapse blasts from a B-cell lymphoma that had both membrane IgM and IgD before initiation of treatment; (3) at diagnosis, bone marrow blasts from a child with T-like leukemia expressed both T antigen and E receptors, but at relapse, bone marrow and pleural fluid cells expressed only T antigens. We postulate that these phenotype shifts may be due to selective effects of therapy on cells at different stages of differentiattion.

Adolescent↗
PubMedDate not supplied

Intensive alternating drug pairs after remission induction for treatment of infants with acute lymphoblastic leukemia: A Pediatric Oncology Group Pilot Study.

PURPOSE: Infants with acute lymphoblastic leukemia (ALL) often enter remission; however, they have a high rate of relapse. To prevent relapse, infants' tolerance of and benefits from early intensive rotating drug pairs as part of therapy were studied. METHODS: After prednisone, vincristine, asparaginase, and daunorubicin induction, 12 intensive treatments (ABACABACABAC) were administered in 30 weeks: A, intermediate dose methotrexate (MTX) and intermediate dose mercaptopurine (MP); B, cytosine arabinoside (Ara-C) and daunorubicin (DNR); C, Ara-C and teniposide (VM-26). Triple intrathecal chemotherapy (Ara-C, MTX, and hydrocortisone) was administered for central nervous system prophylaxis. Continuation therapy consisted of weekly MTX and daily MP for a total of 130 weeks of continuous complete remission. RESULTS: Thirty-three infants (1 year old or younger) with newly diagnosed ALL were treated. Two infants did not respond to induction, 1 died from sepsis during continuation, 1 received a bone marrow transplant, and 24 relapsed. Median time to relapse was 39 weeks. The event-free survival rate at 5 years was 17% (standard error +/- 7.7%). The most significant toxicities occurred during intensification and included fever-neutropenia and bacterial sepsis. CONCLUSION: Although early intensive rotating therapy is tolerable, the relapse-free survival rate remains poor for infants treated with the schedule on this protocol.

Antineoplastic Combined Chemotherapy Protocols↗