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Biomedical subjects

D R Burger

Publications and source records attributed to D R Burger.

At least 37 records · Page 2Linked to original sources
PubMed1981

Human lymphocytes can generate thymus-independent as well as thymus-dependent anti-hapten plaque-forming cell responses in vitro.

Human lymphocytes from peripheral blood, tonsils, and adenoids produced hapten-specific anti-TNP antibodies after in vitro stimulation with TNP-Ba. This antigen did not appear to behave as a polyclonal activator since TNP-Ba-stimulated cells lysed TNP-conjugated sheep erythrocytes (SRBC) but not unconjugated SRBC or DPPC-conjugated SRBC, whereas cells from PWM-stimulated cultures formed hemolytic plaques with both haptenated and unhaptenated targets. In addition, TNP-Ba generated PFC were inhibitable by soluble hapten (TNP-EACA or TNP-BSA). B cells depleted of T cells (less than 1% E-RFC cells) were able to respond to TNP-Ba but not to PWM or TNP-KLH. When varying ratios of T and B cells were added to cultures the TNP-Ba anti-TNP response was found to have a linear correlation with the number of B cells added (r = 0.987) and was maximal in the absence of added T cells. This was in contrast to the response to TNP-KLH, which required T cells at a particular T:B ratio for optimal induction of anti-TNP PFC. Thus, both T-dependent and T-independent anti-hapten responses could be elicited in human lymphoid cell cultures.

Adenoids↗
PubMed1979

Myelin basic protein binding cells in active multiple sclerosis.

A sensitive, antigen-specific rosetting technique was used to enumerate blood cells that bind myelin basic protein (BP) in MS patients and controls. Sixteen of 23 MS patients in exacerbation but only 7 of 48 in remission formed elevated numbers of rosettes. Five of the latter 7 patients had recovered from an exacerbation within four months of the laboratory evaluation. Eight of 20 patients with progressive MS, all of whom had had disease for more than four years, had BP rosette-forming cells. None of the 16 normal volunteers and 1 of 8 neurological controls had BP rosette-forming cells. These results suggest that BP-binding cells in MS are confined to patients in acute exacerbation or within four months of activity, and those who have had progressive disease for at least four years.

Antigen-Antibody Reactions↗
PubMed1979

Immune response to melanoma extracts in three melanoma-prone families.

Immune reactivity to melanoma extracts was measured by the leukocyte adherence inhibition (LAI) test in 40 members of 3 melanoma-prone families. The melanoma patients had a wide range of responsiveness to the extract, the highest responder being a 10-year survivor. As a group, family members (including spouses) without disease had significantly elevated LAI responses compared to those of unrelated controls (P less than 0.01). Within the families, members with close exposure to melanoma patients for 10 years or more had a significantly higher response to melanoma antigen than did members with 0-5 years of close exposure (P less than 0.05). Responses of spouses and members at high risk of developing melanoma (B-K mole syndrome) also correlated with length of exposure to patients, which suggests that the elevated LAI response was not genetically determined. The high frequency of positive responses to melanoma antigens in these families, particularly in spouses, suggests the presence of transmissible melanoma-associated material capable of immunizing persons in contact with melanoma patients.

Antigens, Neoplasm↗
PubMed1979

Assessment of the mechanism of the leukocyte adherence inhibition test.

This study was designed to elucidate the mechanism of the leukocyte adherence inhibition (LAI) test in man. To identify the reactive cell types, enriched leukocyte populations (dextran-separated leukocytes and Hypaque-Ficoll-isolated mononuclear cells and neutrophils, as well as rosette-isolated B- and T-lymphocytes) were tested for leukocyte adherence in the absence of serum to tumor-specific antigens. LAI reactivity was not restricted to any of the enriched populations, suggesting the involvement of multiple cell types. Attempts to demonstrate soluble lymphocyte factors in the LAI mechanism have been uniformly negative. In contrast, factors in serum of immune donors were able to arm naive cells to be specifically responsive. This suggests a role for serum factors in the mechanism of LAI reactivity and partially explains the participation of multiple cell types in the responses observed. In additional studies, we could not document a correlation between the magnitude of the dermal test (delayed cutaneous hypersensitivity) and the magnitude of the LAI response in patients with squamous cell carcinoma of the head and neck. In 34 of 54 of these patients, there was agreement between the two tests (both positive, 27 of 54; both negative, 7 of 54). In the remaining 20 patients, the dermal test was greater than 5 mm while the LAI test was negative (less than 30% inhibition).

Antibodies, Neoplasm↗
PubMed1979

Human transfer factors: structural properties suggested by HPRP chromatography and enzymatic sensitivities.

Leukocyte extracts containing human transfer factor (TF) were fractionated by exclusion chromatography, and the active fraction (Sephadex G25, Fraction IIIa) was subjected to high pressure, reverse phase (HPRP) chromatography and enzymatic degradation. TF activity was assessed by the systemic transfer of dermal skin test reactivity from KLH-immunized donors to naive recipients. Preparative HPRP chromatography resolved Fraction IIIa into multiple chromophoric regions, two of which demonstrated transfer of KLH reactivity. Alkaline phosphatase treatment of Fraction IIIa converted the major ultraviolet-absorbing component, 5'-inosine monophosphate, to inosine and resulted in TF activity being restricted to one region. This HPRP region (R1A) contained less than 1% of the UV254 active material in Fraction IIIa but greater than 90% of the reactivity. The sensitivity of TF to pronase, proteinase K, phosphodiesterase I, and phosphodiesterase II was evaluated by inhibition of systemic transfer of KLH reactivity. Pronase and proteinase K destroyed systemic transfer activity and the pronase destruction could be inhibited with traysylol. Phosphodiesterase I, a 3' exonuclease, destroyed activity, whereas phosphodiesterase II, a 5' exonuclease, did not. The data are consistent with a phosphodiester-containing polypeptide in the structure of human TF for KLH reactivity.

Alkaline Phosphatase↗
PubMed1979

Association of melanoma tumor antigen activity with beta2-microglobulin.

The majority of melanoma tumor antigen activity present in melanoma extracts derived from fresh tumor tissue binds to a Sepharose-anti-beta2-microglobulin adsorbent. Removal of HLA antigens from the extracts of melanoma tissue by using a KBr flotation technique did not reduce either the tumor antigen activity of the extracts or the binding of melanoma tumor antigen (MTA) activity to the Sepharose-anti-beta2-microglobulin adsorbent. The complete blocking of MTA activity by pretreating the anti-beta2-microglobulin adsorbent with beta2-microglobulin and the lack of detectable MTA binding to a Sepharose anti-normal human serum adsorbent demonstrated the specificity of the binding of MTA to the anti-beta2-microglobulin adsorbent.

Antigens, Neoplasm↗
PubMed1978

Changes in tumor immunity during therapy determined by leukocyte adherence inhibition and dermal testing.

Leukocyte adherence inhibition (LAI) is an easily carried out in vitro test for tumor reactivity which is based on the prevention of adherence of leukocytes incubated with antigen to which the donor is immune. In this study a comparison is made with dermal response to tumor antigen. A total of 234 patients were tested, 74 of whom had melanoma, 111 of whom had squamous cell carcinoma of the head and neck, 18 of whom had neuroblastoma and 31 of whom had other tumors. Forty-two persons without tumors acted as controls for the LAI test. A high degree of correlation was found between LAI and dermal response. Furthermore, LAI exhibited marked tumor specificity and showed a ten-fold greater sensitivity than dermal response. LAI may be used to monitor serial changes in tumor reactivity in cancer patients.

Adolescent↗
PubMed1978

Transference of cell mediated immunity in patients with head and neck cancer.

A group of 67 patients with head and neck cancer has been studied of which 40 have received immunologic transfer factor from a normal donor pool. Examination of these patients revealed that lymphocyte reactivity to nonspecific mitogrens is depressed in patients who have head and neck cancer to a much greater extent than is seen in patients with other types of tumors. Furthermore, the depression is more prevalent among patients who have been treated with radiation. Patients in the head and neck group who have received transfer factor show an initial decreased response to PHA stimulation in culture. This is not seen in a control group of head and neck cancer patients or in patients with nonsquamous cander. Thymus-derived lymphocytes are depressed in patients with head and neck cancer, irrespective of whether they have received radiation. Th T-lymphocyte levels increased in eight of 38 patients who received nonimmune transfer factor, but 7 of these were in the group who had not received radiation. The leukocyte adherence inhibition (LAI) test has been used to determine tumor immunity in the patient test group. Changes in tumor immunity did not occur in those patients who received normal nonimmune transfer factor. Studies are presently in progress which provide for treatment of patients with head and neck cancer with specific squamous carcinoma immune transfer factor.

Antibody Specificity↗
PubMed1977

Structure and biological function of human IgD. IX. Anti-IgD activation of human lymphocytes.

Human peripheral lymphocytes were stimulated to incorporate tritiated thymidine when cultured with anti-sigma. The stimulation of lymphocytes by anti-sigma inversely correlates to PHA-induced lymphocyte transformation. In addition, lymphocytes from individuals with low serum IgD levels exhibited a significant response to anti-sigma, whereas, those with normal or slightly elevated levels of serum IgD showed minimal stimulation. This study is the first to provide evidence that cell surface IgD may regulate metabolic functions of lymphocytes and is consistent with the idea that IgD is a 'triggering' receptor.

Antibodies, Anti-Idiotypic↗
PubMed1977

Structure and biological functions of human IgD. XII. Anti-IgD enhancement of PHA responsiveness in patients with chronic lymphocytic leukaemia.

Specifically purifed anti-human delta stimulated the in vitro incorporation of [3H]thymidine by human peripheral lymphocytes from patients with chronic lymphocytic leukaemia (CLL). The peak response varied between individuals; those with 5--52% IgD-bearing lymphocytes exhibited maximum stimulation at 3 days, whereas a patient with only 1% IgD-bearing cells showed optimal activation at 6 days. In agreement with others, our data indicated that, in most instances, lymphocytes from patients with CLL respond poorly to PHA. One of the most important findings in this study is the enhancement of PHA responsiveness by anti-delta. Lymphocytes that exhibited reduced responsiveness to PHA alone, when pre-treated with anti-delta, showed transformation greater than the sum of the anti-delta plus PHA responses.

Aged↗
PubMed1977

Human transfer factor: fractionation by electrofocusing and high pressure, reverse phase chromatography.

The biologically active fraction of human transfer factor (Sephadex G-25, fraction III) has been separated by exclusion chromatography into two component fractions (IIIa and IIIb). Fraction IIIa transferred donor reactivities to PPD or KLH into 9 of 9 recipients. Fraction IIIb did not transfer donor reactivities (0 of 8 transfers) but did produce both antigen-independent and antigen-dependent dermal reactions in recipients. Fractionation by electrofocusing and high pressure reverse phase chromatography revealed that IIIa has a major UV254 absorbing component and that fraction IIIb has at least three major and three minor UV absorbing components. The major component of IIIa was isolated by preparative electrofocusing, had an isoelectric point of 1.6, and transferred KLH reactivity to four of five recipients.

Chemical Fractionation↗