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F Strickland

Publications and source records attributed to F Strickland.

5 recordsLinked to original sources
PubMed1988

Regulation of idiotope expression. III. H-2 influences the magnitude and the idiotypy of a T-independent antibody response in mice of certain genetic backgrounds.

Antibody response to the phosphocholine (PC) epitope on Streptococcus pneumoniae R36a (Pn), a T-independent Ag type 2, was studied in H-2 congenic mouse strains. The PC-specific antibody plaque-forming cells (PFC) were enumerated in the spleen at various intervals after the primary Pn injection, and the proportion of PFC that produced antibody expressing the AB1-2 idiotope (Id) was determined by using the corresponding monoclonal anti-Id. AB1-2 is a cross-reactive Id, detectable on germline-encoded PC antibody of the T15 family, and on most, but not all, somatic variants of that antibody. The specific PFC responses in BALB/c (H-2d) and BALB.B (H-2b) strains were of comparable magnitude and most, if not all, PFC were ABl-1 Id-positive (AB1-2+). This was not the case in the responses of the B10D2 (H-2d) vs C57BL/10 (H-2b) strains and the D1.C (H-2d) vs D1.LP (H-2b) strains (on DBA/1 background). In each of these pairs, the H-2d mice were high responders, and the response was dominated by AB1-2 Id (greater than or equal to 80% AB1-2+ PFC at the peak, on day 5). The H-2b mice were low responders, and only a minor proportion of PFC (less than or equal to 30%) were AB1-2+; an increase of AB1-2+ was seen later in the response (d.10). The results of PFC assays were confirmed by measuring the PC-binding antibody and AB1-2 Id in the sera of D1.C and D1.LP mice immunized repeatedly with Pn. Moreover, D1.LP mice that had very low levels of AB1-2 Id had higher serum levels of antibody expressing two other T15 Id, B36-82, and B24-44. The B36-82 and B24-44 Id have been previously found on somatic variants of PC antibody expressed independently of the Ab1-2 Id. The concentrations of these two Id in D1.LP mice after repeated immunization approached those in D1.C. These results indicate that 1) the H-2 allelism may have a significant effect on TID antibody response in mice of a certain genetic background, but not in the BALB/c; and 2) the idiotypic repertoire of the response may be influenced by H-2 at the level of clonal variants of PC-reactive cells.

Alleles↗
PubMed1981

Adjuvant effect of nonionic block polymer surfactants in humoral and cellular immunity.

The adjuvant activities of four chemically similar, but physicochemically different nonionic surface-active agents called pluronic polyols F 68, L 31, L 101 and L 121 were studied. These four agents were tested in mice using an experimental model developed for studying the adjuvant activity of the cationic surface-active agent dimethyl dioctadecyl ammonium bromide (DDA). L 121 and DDA enhanced the primary antibody response to sheep red blood cells (SRBC) while F 68, L 31 and L 101 suppressed this response. The secondary humoral response to SRBC was enhanced by the polyol L 121 while the secondary response to dinitrophenylated bovine serum albumin (DNP22-BSA) was enhanced by both L 121 and L 101. DDA and the polyol L 101 were very effective adjuvants for induction of delayed-type hypersensitivity (DTH) to SRBC and DNP22-BSA after intracutaneous immunization of mice with a mixture of antigen and adjuvant. Since the four pluronic polyols were composed of identical chemical constituents, we proposed that difference in their activities as adjuvants were due to variation in their physicochemical properties. A correlation was found between a physicochemical parameter, the hydrophilelipophile balance (HLB), and the adjuvant activities of the pluronic polyols and several other types of nonionic surface-active agents. The agents which were strong adjuvants all had HLB values within a narrow range which classified them as spreading agents.

Adjuvants, Immunologic↗
PubMed1981

The adjuvant activity of nonionic block polymer surfactants. I. The role of hydrophile-lipophile balance.

We developed an experimental model for studying the physicochemical basis of the adjuvant activity of surface-active agents. Pluronic polyols are chemically similar but physicochemically diverse surface-active agents composed of polymers of hydrophilic polyoxyethylene and lipophilic polyoxypropylene. One of them, L121, was found to be a powerful adjuvant for increasing antibody formation to BSA in mice when injected in an oil-in-water emulsion. Another, L101, was less effective in increasing antibody formation, but was more effective in inducing granulomatous inflammation. Three others had little effect on either response. The ability of these and other surface active agents to serve as adjuvants correlated with a physicochemical parameter, the hydrophile-lipophile balance (HLB). All of the surfactants with strong adjuvant activity have HLB values of less than 2. They are strongly lipophilic and promote the retention of macromolecules by oil drops in oil-in-water emulsions. We propose that the adjuvant activity of these compounds is dependent on their ability to concentrate the adjuvant, immunogen, and host proteins on hydrophobic surfaces, where they are more effectively presented to cells of the immune system.

Adjuvants, Immunologic↗
PubMed1975

Immunization with a lipid-conjugated membrane antigen to suppress growth of a fibrosarcoma induced by simian virus 40.

The covalent conjugation of fatty acid to a tumor cell membrane preparation transformed it from an antigen that enhanced tumor growth to one that suppressed it. A crude cell membrane preparation was made by sequential hypertonic and hypotonic salt extraction of tumor cells from a fibrosarcoma induced in hamsters by simian virus 40. The membranes were chemically conjugated with dodecanoic anhydride in 0.5 M carbonate buffer (pH 9.0). Injection of unmodified membranes 10 days before transplantation of live tumor cells produced clear-cut enhancement of the tumor growth rate. In contrast, injection of lipid-conjugated membranes in a similar dose and protocol suppressed tumor growth. The lymphoid proliferative reactions to the tumor cells as demonstrated by the histology of both the tumor and regional lymph nodes were consistent with the hypothesis that unmodified membranes stimulated the production of antibody which participated in the enhancement of tumor growth, and that lipid-conjugated membranes stimulated the production of cell-mediated immunity which suppressed this growth.

Animals↗